Atari PILOT II / Super PILOT

Harry B. Stewart

On November, 6th, 2016, Kevin Savetz uploaded scans of the source code for Atari PILOT to archive.org. They were provided to him by the author, Harry Stewart, and here’s a reasonably accurate transcription.

                  ;
                  ; PILOT PROGRAM EQUATE FILE
                  ;
                  ; EDIT #99 -- 07-JUN-83
                  ;

      = 0000      DEBUG   = 0             ; INCLUDE DEBUG CODE IF 1, DON'T IF 0.
      = 0000      LITPEN  = 0             ; INCLUDE LIGHTPEN CODE IF 1, DON'T IF 0.
      = 0000      LOGGRP  = 0             ; INCLUDE LOGICAL OPERATORS IF 1, DON'T IF 0.
      = 0000      DOS     = 0             ; INCLUDE 'DOS' COMMAND IF 1, DON'T IF 0.
      = 0000      FALSE   = 0

                  ; COLLEEN SYSTEM I/O

      = E456      CIO     = $E456

      = E400      IOVBAS  = $E400         ; COLLEEN VECTOR BASE ADDRESS.
      = E406      EPUTC   = $E406         ; "E:" PUT CHARACTER.
      = E414      SGETC   = $E414         ; "S:" GET CHARACTER.
      = E416      SPUTC   = $E416         ; "S:" PUT CHARACTER.
      = E41A      SSPEC   = $E41A         ; "S:" SPECIAL.
      = E424      KGETC   = $E424         ; "E:" GET CHARACTER.

      = 0010      IOCBSZ  = 16            ; # OF BYTES PER IOCB.
      = 0000      IOCB0   = $00           ; CONSOLE INPUT/OUTPUT.
      = 0010      IOCB1   = IOCB0+IOCBSZ  ; (UNUSED).
      = 0020      IOCB2   = IOCB1+IOCBSZ  ; GRAPHICS INPUT & OUTPUT.
      = 0030      IOCB3   = IOCB2+IOCBSZ  ; LOAD & SAVE I/O.
      = 0040      IOCB4   = IOCB3+IOCBSZ  ; IN: & OUT: USE IOCB4 THRU IOCB7.
      = 0070      IOCB7   = 3*IOCBSZ+IOCB4

      = 0340      ICHID   = $0340         ; IOCB HANDLER I.D.
      = 0341      ICDNO   = ICHID+1       ; DEVICE #.
      = 0342      ICCOM   = ICDNO+1       ; COMMAND BYTE.
      = 0343      ICSTA   = ICCOM+1       ; STATUS BYTE.
      = 0344      ICBAL   = ICSTA+1       ; BUFFER ADDRESS (LO).
      = 0345      ICBAH   = ICBAL+1       ; BUFFER ADDRESS (HI).
      = 0346      ICRLL   = ICBAH+1       ; RECORD LENGTH (LO).
      = 0347      ICRLH   = ICRLL+1       ; RECORD LENGTH (HI).
      = 0348      ICBLL   = ICRLH+1       ; BUFFER LENGTH (LO).
      = 0349      ICBLH   = ICBLL+1       ; BUFFER LENGTH (HI).
      = 034A      ICAUX1  = ICBLH+1       ; AUX1.
      = 034B      ICAUX2  = ICAUX1+1      ; AUX2.

      = 0022      ICCOMZ  = $0022         ; ZERO PAGE IOCB COMMAND BYTE.

      = 0003      OPEN    = $03           ; OPEN COMMAND.
      = 000C      CLOSE   = $0C           ; CLOSE COMMAND.
      = 0007      GETC    = $07           ; GET CHARACTER COMMAND.
      = 000B      PUTC    = $0B           ; PUT CHARACTER COMMAND.
      = 0005      GETR    = $05           ; GET RECORD COMMAND.
      = 0009      PUTR    = $09           ; PUT RECORD COMMAND.

      = 0004      OREAD   = $04           ; OPEN DIRECTION.
      = 0008      OWRIT   = $08           ; OPEN DIRECTION.
      = 0010      SPLIT   = $10           ; SPLIT SCREEN
      = 0020      NOCLR   = $20           ; INHIBIT SCREEN CLEAR OPTION.

      = 000D      CR      = $0D           ; INTERNAL <CR> CODE

      = 001C      CUP     = $1C           ; CURSOR UP.
      = 001D      CDOWN   = $1D           ; CURSOR DOWN.
      = 001E      CLEFT   = $1E           ; CURSOR LEFT.
      = 001F      CRIGHT  = $1F           ; CURSOR RIGHT.
      = 009B      EOL     = $9B           ; ATASCII END OF LINE.
      = 007D      CLEAR   = $7D           ; MONITOR CLEAR SCREEN.
      = 00FD      BELL    = $FD           ; BELL CODE.
      = 005C      BSLASH  = $5C           ; BACKSL SLASH
      = 007C      VBAR    = $7C           ; VERTICAL BAR
      = 005B      SBRACK  = $5B           ; SQUARE BRACKET
      = 0027      SQUOTE  = $27           ; SINGLE QUOTE
      = 007F      TAB     = $7F           ; TAB.

                  ; O.S. ROM VECTORS

      = E462      XITVBV  = $E462         ; EXIT VBLANK VECTOR.
      = E45C      SETVBV  = $E45C         ; SET VECTOR ROUTINE.

                  ; O.S. DATA BASE

      = 0244      COLDST  = $0244         ; SYSTEM COLDSTART FLAG.
      = 000C      DOSINI  = $000C
      = 006A      RAMTOP  = $006A         ; TOP OF SCREEN ADDRESS (MSB).
      = 004F      COLRSH  = $004F         ; ATTRACT HUE SHIFT.
      = 004E      DRKMSK  = $004E         ; ATTRACT LUM LIMIT.
      = 02E7      MEMLO   = $02E7         ; LOWEST AVAILABLE RAM [WORD].
      = 02E5      MEMHI   = $02E5         ; HIGHEST AVAILABLE PAM [WORD].
      = 000E      APPMHI  = $000E         ; APPLICATION MEM HI [WORD].
      = 0011      BREAK   = $0011         ; BREAK KEY FLAG.
      = 02FC      CH      = $02FC         ; KEYBOARD MATRIX CODE INPUT.
      = 02F0      CRSINH  = $02F0         ; CURSOR INHIBIT FLAG.
      = 02FE      DSPFLG  = $02FE         ; CONTROL BYTE DISPLAY FLAG.
      = 0230      SDLSTL  = $0230         ; DISPLAY LIST ADDRESS.
      = 0232      SSKCTL  = $0232
      = 0012      RTCLOK  = $0012         ; 60 HZ CLOCK.
      = 0052      LMARGN  = $0052         ; SCREEN LEFT MARGIN.
      = 0053      RMARGN  = $0053         ; SCREEN RIGHT MARGIN.
      = 0055      COLCRS  = $0055         ; SCREEN COLUMN [WORD)
      = 0054      ROWCRS  = $0054         ; SCREEN ROW [BYTE)
      = 0057      DINDEX  = $0057         ; S: SCREEN MODE.
      = 0058      SAVMSC  = $0058         ; SCREEN START ADDR.
      = 02BF      BOTSCR  = $02BF         ; TEXT SCREEN SIZE.
      = 0008      WARMST  = $0008         ; WARMSTART FLAG (0 IF POWERUP).
      = 000A      DOSVEC  = $000A         ; DOS START VECTOR.
      = 026E      FINE    = $026E         ; SCROLL SELECT.
      = 026F      GPRIOR  = $026F         ; PLAYER/PLAYFIELD PRIORITY.
      = 022F      DMACT   = $022F         ; DMA CONTROL BYTE.
      = 02C0      PCOLR0  = $02C0         ; PLAYER/MISSILE COLOR.
      = 02C4      COLOR0  = $02C4         ; COLOR REGISTER 0 VALUE.
      = 0270      PADDL0  = $0270         ; PADDLE CONTROLLER 0.
      = 0278      STICK0  = $0278         ; JOYSTICK 0.
      = 027C      PTRIG0  = $027C         ; PADDLE TRIGGER 0.
      = 0284      STRIG0  = $0284         ; JOYSTICK TRIGGER 0.
      = 0234      LPENH   = $0234         ; LIGHTPEN HORIZONTAL POSITION.

      = 0235      LPENV   = $0235         ; LIGHTPEN VERTICAL POSITION.
      = 0291      TXTCOL  = $0291         ; SPLIT SCREEN TEXT COLUMN.
      = 0290      TXTROW  = $0290         ; SPLIT SCREEN TEXT ROW.
      = 02B6      INVFLG  = $02B6         ; INVERSE VIDEO FLAG FOR KEYBOARD.
      = 0200      VDSLST  = $0200         ; DISPLAY LIST INTERPRUPT.
      = 0220      CDTMV5  = $0220         ; SYSTEM TIMER VALUE.
      = 0224      VVBLKD  = $0224         ; DEFERRED VBLANK ROUTINE.
      = 02FF      SSFLAG  = $02FF         ; START/STOP FLAG.

                  ; PILOT ERROR CODES

      = 0080      NS      = $80           ; "NOT A SYNTAX ERROR" FLAG.
      = 0001      RDYTXT  = 1             ; READY.
      = 0081      EOPERR  = 1+NS          ; END OF PROGRAM STORAGE REACHED DURING RUN.
      = 0081      AUTOXT  = 1+NS          ; EXIT AUTO-INPUT MODE.
      = 0002      CNDERR  = 2             ; CONDITION FIELD ERROR (':' EXPECTED).
      = 0002      NSTERR  = 2             ; GRAPHICS SUB-COMMAND NESTING ERROR.
      = 0081      ENDERR  = 1+NS          ; USE STACK EMPTY ON END COMMAND.
      = 0002      JNKERR  = 2             ; JUNK AT END OF STATEMENT.
      = 0086      IOERR   = 6+NS          ; I/O ERROR.
      = 0002      IVCERR  = 2             ; INVALID COMMAND.
      = 0002      ATMERR  = 2             ; INVALID ATOM SYNTAX.
      = 0002      IMPERR  = 2             ; IMPROPER COMMAND PARAMETER.
      = 0089      INSERR  = 9+NS          ; INSUFFICIENT STORAGE FOR OPERATION.
      = 0087      ABTERR  = 7+NS          ; OPERATOR ABORT.
      = 000A      UNDERR  = 10            ; UNDEFINED LABEL OPERAND.
      = 008B      USOERR  = 11+NS         ; USE STACK OVERFLOW.
      = 0002      EXPERR  = 2             ; EXPRESSION ERROR.
      = 008C      INTERR  = 12+NS         ; INTERNAL BUG ERROR.
      = 008D      LNOERR  = 13+NS         ; LINE # OUT OF RANGE.
                  ;         14              IS RESERVED.
      = 000F      OLLERR  = 15            ; OVERLENGTH INPUT LINE.
                  ;         16-21           ARE RESERVED.
      = 0096      FILERR  = 22+NS         ; TOO MANY IN/OUTS.
      = 0017      SIGNON  = 23            ; POWEP-UP SIGN-ON MESSAGE.
      = 0018      TRCMES  = 24            ; TRACE PREAMBLE.
      = 0008      ASTMES  = 8             ; ASTERISKS.
      = 0083      NRCERR  = 3+NS          ; NOT CORRECT COMMAND MODE.
      = 0084      DIVERR  = 4+NS          ; DIVIDE BY ZERO.
      = 0085      SCNERR  = 5+NS          ; SCREEN MODE CONFLICT.
      = 0099      CNTERR  = 25+NS         ; CAN'T CONTINUE.
      = 009A      STPMES  = 26+NS         ; STOP.
      = 009B      RENERR  = 27+NS         ; CAN'T RENUMBER
      = 009C      OVLPER  = 28+NS         ; OVERLAPPING RANGE.
      = 009D      TOMES   = 29+NS         ; " TO ".
      = 009E      NCHGMS  = 30+NS         ; PROGRAM IS UNCHANGED.
      = 009F      DELMES  = 31+NS         ; "YOU ARE ABOUT TO DELETE ".
      = 00A0      DL2MES  = DELMES+1      ; LINES.<CR>ARE YOU SURE?".
      = 0021      SPTERR  = 33            ; NO SPLIT SCREEN.
      = 0022      MODERR  = 34            ; INVALID GRAPHICS MODE.
      = 00A4      FSOFER  = 36+NS         ; FLOOD STACK OVERFLOW.
      = 0025      NMCERR  = 37            ; NO MORE COLORS.
      = 0026      DCAERR  = 38            ; DOUBLE COLOR ASSIGN.

                  ; ATOM IDENTIFIER CODES (PRODUCED BY 'ATOM')

      = 0001      NULL    = 1             ; NULL ATOM.
      = 0002      NUM     = 2             ; NUMERIC CONSTANT.
      = 0004      NVAR    = 4             ; NUMERIC VARIABLE OR POINTER TO WORD.
      = 0008      SVAR    = 8             ; STRING VARIABLE.
      = 0010      USVAR   = 16            ; UNDEFINED STRING VARIABLE.
      = 0020      TEXT    = 32            ; TEXT.
      = 0040      OPR     = 64            ; OPERATOR.
      = 0080      BPTR    = 128           ; POINTER TO BYTE.

                  ; GRAPHICS OPERATORS

      = 0011      FILL    = $11
      = 0012      FILLTO  = $12
      = 0009      DRAW    = $09
      = 000A      DRAWTO  = $0A
      = 0005      GO      = $05
      = 0006      GOTO    = $06

                  ; EDGE DETECT STATUS BITS

      = 0008      ELEFT   = 8             ; LEFT EDGE.
      = 0004      ERIGHT  = 4             ; RIGHT EDGE.
      = 0002      EBOTOM  = 2             ; BOTTOM EDGE.
      = 0001      ETOP    = 1             ; TOP EDGE.

                  ; PILOT CONFIGURATION PARAMETERS.

      = 0030      USTKSZ  = 48            ; 24 LEVELS IN USE STACK.
      = 0002      ELEVEL  = 2             ; # OF EXPRESSION STACK () LEVELS.
      = 000E      ESTKSZ  = 4*ELEVEL+6    ; EXPRESSION STACK SIZE.
      = 00FE      ACCLNG  = 254           ; ACCEPT BUFFER LENGTH.
      = 00FE      TEXLNG  = 254           ; TEXT EXPRESSION BUFFER LENGTH.
      = 007A      LINLNG  = 122           ; COMMAND/ACCEPT INPUT LINE LENGTH.
      = 270F      MAXLN   = 9999          ; MAXIMUM PROGRAM LINE NUMBER.
      = 0004      AUREGS  = 4             ; 4 AUDIO REGISTERS.
      = 0007      SCNMOD  = 7             ; 4 COLOR, 160 * 96.
      = 000F      DNSIZE  = 15            ; DEVICE/FILENAME MAXIMUM LENGTH.
      = 0028      TCOL    = 40            ; TEXT SCREEN # OF COLUMNS.
      = 0018      TROW    = 24            ; TEXT SCREEN # OF ROWS.
      = 000A      INBFSZ  = 10            ; MAXIMUM SUBCOMMAND LENGTH.

                  ; HARDWARE EQUATES

      = D200      AUDF1   = $D200         ; AUDIO #1 FREQUENCY DIVIDER.
      = D201      AUDC1   = AUDF1+1       ; AUDIO #1 TYPE/VOLUME.
      = D20F      SKCTL   = $D20F         ; SERIAL PORT CONTROL.
      = D20F      SKSTAT  = $D20F         ; SERIAL PORT STATUS.
      = D208      AUDCTL  = $D208         ; AUDIO CONTROL REGISTER.
      = D302      PACTL   = $D302         ; PIA CASSETTE CONTROL.
      = 0034      CASSON  = $34           ; CASSETTE ON.
      = 003C      CASSOF  = $3C           ; CASSETTE OFF.
      = D20A      PKYRND  = $D20A         ; POKEY RANDOM NUMBER.
      = D01F      CONSOL  = $D01F         ; START/SELECT/OPTION KEY READ.
      = D400      DMACTL  = $D400         ; DMA CONTROL REG.
      = D407      PMBASE  = $D407         ; PLAYER/MISSILE BASE ADDRESS REGISTER.
      = D010      GRAFP3  = $D010         ; PLAYER 3 DATA.
      = D01D      GRACTL  = $D01D         ; GRAPHICS CONTROL REG.
      = D00B      SIZEP3  = $D00B         ; PLAYER 3 SIZE.
      = D000      HPOS0   = $D000         ; PLAYER POSITIONS.
      = D017      COLPF1  = $D017         ; PLAYFIELD 1 COLOR.
      = D018      COLPF2  = $D018         ; PLAYFIELD 2 COLOR.
      = D40A      WSYNC   = $D40A         ; WAIT FOR SYNC.
      = D40E      NMIEN   = $D40E         ; NMI ENABLE.

                  ; COLOR EQUATES

      = 0042      CRED    = $42
      = 0084      CBLUE   = $84
      = 001A      CYELLO  = $1A
      = 0001      CBLACK  = $01

                  ; MISCELLANEOUS

      = 0080      PCUP    = 128           ; PEN = 'UP'.
      = 0040      PCDN    = 64            ; PEN = 'DOWN'.

      = 0000      LSMLL   = 0             ; LETTERS = 'SMALL'.
      = 0001      LMED    = 1             ; LETTERS = 'MEDIUM'.
      = 0002      LLRG    = 2             ; LETTERS = 'LARGE'.

      = 0001      EWRAP   = 1             ; EDGE = 'WRAP'.
      = 0002      EHALT   = 2             ; EDGE = 'HALT'.
      = 0004      EBNC    = 4             ; EDGE = 'BOUNCE'.
      = 0008      EFREE   = 8             ; EDGE = 'FREE'.

                  ; ALGORITHMS REQUIRE KOFF=0, KON=1.

      = 0000      KOFF    = 0             ; 'OFF'.
      = 0001      KON     = 1             ; 'ON'.

      = FFFF      EONMLS  = $FFFF         ; END OF 'NMSBUF' LIST.

      = 00DF      UC      = $DF           ; LOWER -> UPPER CASE.
      = 0020      LC      = $20           ; UPPER -> LOWER CASE.

      = 00FF      UP      = $FF           ; FLOOD DIRECTIONS.
      = 0001      DOWN    = 1

      = 0001      STRTKY  = 1             ; CONSOLE KEY DEFS.
      = 0002      SELKEY  = 2
      = 0004      OPTKEY  = 4
      = 0007      ANYKEY  = STRTKY+SELKEY+OPTKEY

      = 0001      TXSL    = 1             ; SCREEN MODE = TEXT, SMALL LETTERS.
      = 0002      TXML    = 2             ; SCREEN MODE = TEXT, MEDIUM OR LARGE LETTERS.
      = 0004      GRSS    = 4             ; SCREEN MODE = GRAPHICS, SPLIT.
      = 0008      GRFS    = 8             ; SCREEN MODE = GRAPHICS, FULL.

                  ; 'NAME' TYPES.

      = 0080      ATRSTR  = $80           ; 'STRING' VARIABLE.
      = 0040      ATRNUM  = $40           ; 'NUMERIC' VARIABLE.
      = 0020      ATRIO   = $20           ; 'I/O' DEVICE.
      = 0000      ATRLIN  = 0             ; STATEMENT 'LINE'.

                  ; RESERVED COMMAND 'TOKENS' AND 'USRTAB' SIZE.

      = 00FE      TKNCNT  = $FE           ; COMMAND CONTINUATION.
      = 00FF      TKNNUL  = $FF           ; NULL COMMAND.

                  ; ROBOT TURTLE DRIVER COMMANDS.

      = 0000      RBOFF   = 0             ; 'ROBOT OFF'.
      = 0020      RBON    = $20           ; 'ROBOT ON'.
      = 0001      RBEYES  = 1             ; 'EYES'.
      = 0002      RBPEN   = 2             ; 'RPEN'.
      = 0003      RBHORN  = 3             ; 'HORN'.
      = 0080      RBFWD   = $80           ; 'GO +'.
      = 0081      RBBACK  = $81           ; 'GO -'.
      = 0040      RBLEFT  = $40           ; 'TURN +'.
      = 0041      RBRGHT  = $41           ; 'TURN -'.

                  ; LOAD TYPES.

      = 0001      KLOAD   = 1
      = 0002      KMERGE  = 2
      = 0003      KAPPND  = 3

                  ;
                  ; PILOT DATA BASE.
                  ;

0000  = 0080              ORG     $0080
      = 0080      DTAB    = *            ; BASE ADDRESS FOR DXXXI UTILITIES & OTHERS.

0080  = 0004      INLN    DS 4           ; INPUT LINE POINTER.
0084  = 0002      NXTLN   DS 2           ; NEXT LINE POINTER (RUN MODE).
0086  = 0001      ACOLR2  DS 1           ; AUTO-NUMBER COLOR REGISTER 2.
0087  = 0001      ACOLR1  DS 1           ; AUTO-NUMBER COLOR REGISTER 1.
0088  = 0004      ACLN    DS 4           ; ACCEPT LINE POINTER.
008C  = 0004      TELN    DS 4           ; TEXT EXPRESSION RESULT POINTEP.

0090              TABADR
0090  = 0002      TBLBAS  DS 2           ; COMMAND TABLE POINTER.

0092  = 0001      EXEC    DS 1           ; 0 = SYNTAX CHECK, ELSE EXECUTE (FOR X-ROUTINES).

0093  = 000E      EXPSTK  DS ESTKSZ      ; EXPRESSION STACK.
00A1  = 0006      TEMP    DS 6           ; TEMPORARY STORAGE FOR BOTTOM LEVEL ROUTINES.
00A7  = 0004      TEMP2   DS 4           ; MORE TEMPORARY STORAGE.
00AB  = 0003      XTEMP   DS 3           ; TEMPORARY STORAGE FOR X-ROUTINES.

00AE  = 0002      S1L     DS 2           ; DYNAMIC STORAGE AREA LIMITS.
00B0  = 0002      S1H     DS 2
00B2  = 0002      S2L     DS 2
00B4  = 0002      S2H     DS 2

00B6  = 0002      POINT   DS 2           ; 'ATOM' RETURN PARAMETER & 'PSF' WORK POINTER.
00B8  = 0002      NUMBER  DS 2           ; 'ATOM' RETURN PARAMETER & 'PSTOP' ERROR # SAVE.

00BA  = 0004      LP      DS 4           ; STRING PACKAGE LIST POINTER.
00BE  = 0004      NP      DS 4           ;                NAME POINTER.
00C2  = 0004      DP      DS 4           ;                DATA POINTER.
00C6  = 0004      MP      DS 4           ;                PATTERN MATCH POINTER.
00CA  = 0004      SP      DS 4           ;                SOURCE POINTER (BOTTOM LEVEL).
00CE  = 0004      PP      DS 4           ;                PATTERN POINTER (BOTTOM LEVEL).

00D2  = 0002      MEMA    DS 2           ; MEMORY MANAGEMENT ADDRESS PARAMETER.
00D4  = 0002      MEMB    DS 2           ;                   BYTE COUNT PARAMETER.
00D6  = 0002      MSP     DS 2           ;                   SOURCE POINTER.
00D8  = 0002      MDP     DS 2           ;                   DESTINATION POINTER.
00DA  = 0002      MBC     DS 2           ;                   WORKING BYTE COUNT.

00DC  = 0002      LINENO  DS 2           ; STATEMENT LINE # (MUST BE IN ZERO PAGE).
00DE  = 0002      LS      DS 2           ; 'XLIST' START LINE #, 'XGRAPH' ITERATION COUNT & 'SCNDEV '.
00E0  = 0002      LEND    DS 2           ; 'XLIST' END LINE 'GMOVE' REGISTER SAVE & 'SCNDEV'.
00E2              MFDEL                  ; MATCH FIELD DELIMITER (',' OR '|'.
00E2  = 0002      ACC     DS 2           ; WORKING NUMERIC ACCUMULATOR.
00E4  = 0002      IOSTAT  DS 2           ; COLLEEN I/O ERROR STATUS [WORD].

00E6  = 0003      GXNEW   DS 3           ; GRAPHICS NEXT POSITION (LSB,MSB,FRACTION).
00E9  = 0003      GYNEW   DS 3           ;
00EC  = 0003      GX      DS 3           ; GRAPHICS X POSITION (LSB,MSB,FRACTION).
00EF  = 0003      GY      DS 3           ; GRAPHICS Y POSITION (LSB,MSB,FRACTION).
00F2  = 0002      THETA   DS 2           ; POLAR ANGLE.


00F4  = 0002      FSTACK  DS 2           ; FLOOD STACK POINTER, & 'SETCLR' TEMP.
00F6  = 0002      ADRESS  DS 2           ; FLOOD SCREEN POINTER 'SSAVE', 'SLOAD' & 'NEWDRW' TEMP.
00F8  = 0002      TRADDR  DS 2           ; TURTLE REP. ADDRESS FOR VBLANK PROCESS.
00FA  = 0002      ALINE   DS 2           ; AUTO-INPUT & RENUMBER LINE NUMBER & TEMP.
00FC  = 0002      AINC    DS 2           ; AUTO-INPUT & RENUMBER LINE INCREMENT.
00FE  = 0001      MATCHF  DS 1           ; MATCH RESULT (0 = FALSE, ELSE MATCH FIELD #).
00FF  = 0001      RUN     DS 1           ; 0 = IMMEDIATE MODE, ELSE RUN MODE.

                  ; REDEFINES OF VARIABLES FOR GRAPHICS USE

      = 00BE      GX1     = NP            ; END    X [3 BYTES].
      = 00C1      GY1     = GX1+3         ; END    Y [3 BYTES].
      = 00C4      GX2     = GY1+3         ; START  X [3 BYTES].
      = 00C7      GY2     = GX2+3         ; START  Y [3 BYTES].
      = 00CA      DELX    = GY2+3         ; DELTA  X [2 BYTES].
      = 00CC      DELY    = DELX+2        ;        Y [2 BYTES].
      = 00CE      GACC    = DELY+2        ; WORKING ACCUMULATOR [4 BYTES].
      = 00D2      GTEMP   = GACC+4        ;         TEMP [4 BYTES).
      = 00D6      GTEMP2  = GTEMP+4       ;         TEMP [4 BYTES].
      = 0093      DELTAR  = EXPSTK        ; DRAW DELTA Y[2].
      = 0095      DELTAC  = DELTAR+2      ; DRAW DELTA X[2].
      = 0097      ROWINC  = DELTAC+2      ; FILL Y INC. [1].
      = 0098      ROWAC   = ROWINC+1      ; DRAW Y ACC. [2].
      = 009A      COLAC   = ROWAC+2       ; DRAW X ACC. [2].
      = 009C      COUNTR  = COLAC+2       ; DRAW COUNTER [2].
      = 009E      ENDPT   = COUNTR+2      ; DRAW E [2].

                  ; REDEFINES OF 'EXPSTK' FOR EDIT COMMANDS.

      = 0093      BLOW    = EXPSTK        ; LOW BRACKET ADDRESS.
      = 0095      BHIGH   = EXPSTK+2      ; HIGH.
      = 0097      BNUM    = EXPSTK+4      ; # OF LINES IN RANGE.
      = 0099      RTMP    = EXPSTK+6      ; RENUMBER TEMP.
      = 009B      R2TMP   = EXPSTK+8      ; ".

0100  = 0500              ORG     $0500

0500  0000        USRTAB  DW 0            ; USER EXTENDABLE COMMAND TABLE.
                                          ; (MSBYTE = 0 IF UNUSED).
0502  0000        RBVECT  DW 0            ; ADDRESS OF ROBOT TURTLE DRIVER.
                                          ; (MSBYTE = 0 IF UNUSED).
0504  = 0002      IOEDIS  DS 2            ; I/O ERROR STOP DISABLE.
                                          ; EXTRA BYTE TO PROTECT AGAINST WORD POKE.
0506  = 0001      EXECF   DS 1           ; CONDITION RESULT (0 = NO EXECUTE, ELSE EXECUTE).
0507  = 0003      XJUMP   DS 3            ; FIRST BYTE = JMP COMMAND (X-ROUTINES).
050A  = 0003      GJUMP   DS 3            ; FIRST BYTE = JMP COMMAND (G-ROUTINES).
050D  = 0003      SJUMP   DS 3            ; FIRST BYTE = JMP COMMAND ('SOP').
0510  = 0001      CTABAT  DS 1           ; 'ATTMBYTE' BYTE FROM 'CMATCH'.

0511  = 0001      DIGIT   DS 1
0512  = 0001      SAVYR   DS 1           ; 'MLOOP' SAVE Y REGISTER.
0513  = 0001      PEN     DS 1           ; GRAPHICS PEN SELECT.
0514  = 0001      GRFLAG  DS 1           ; GRAPHICS MODE FLAG (0=NOT GRAPHICS, ELSE GRAPHICS).
0515  = 0008      AUDIOR  DS AUREGS+AUREGS ; AUDIO VARIABLE POINTERS.
051D  = 0001      AUX1    DS 1           ; I/O AUX1 OVERRIDE BYTE.
051E  = 0001      AUX2    DS 1           ; I/O AUX2 OVERRIDE BYTE.
051F  = 0001              DS 1           ; 'OPNBUF'-1 USED BY 'SCNDEV'.
0520  = 0010      OPNBUF  DS DNSIZE+1    ; DEVICE NAME BUFFER FOR OPEN.
0530  = 0002      CDEST   DS 2           ; 'CHOT' DESTINATION IDENTIFIER & SAVE BYTE.
0532  = 0001      LOADFG  DS 1           ; 0 IF NOT LOADING, ELSE LOADING.
0533  = 0002      MATCHX  DS 2           ; 'XMATCH' FIELD INDEX VALUES.
0535  = 0001      TRACE   DS 1           ; RUN-TIME TRACE FLAG (TRACE IF <> 0).
0536  = 0001      AUTOIN  DS 1           ; AUTO-INPUT FLAG (ACTIVE IF <> 0).

0537  = 0001      GSMODE  DS 1           ; GRAPHICS SCREEN MODE.
0538  = 000A      INLNBF  DS INBFSZ      ; TEMP STORAGE FOR SOURCE TO MATCH.
0542  = 0001      NAMLNG  DS 1           ; 'SAVIT' & 'RESIT'.
0543  = 0001      NOCONT  DS 1                    ; 0 IF CONTINUE O.K.
0544  = 0001      CONKEY  DS 1                    ; 1=START, 2=SELECT, 4=OPTION.
0545  = 0001      SGLSTP  DS 1                    ; SINGLE STEP IF .NE. 0.
0546  = 0001      AXFLAG  DS 1                    ; 1 IF ACCEPT LITERAL.
0547  = 0001      AKFLAG  DS 1                    ; 1 IF ACCEPT KEY.
0548  = 0001      XXXX    DS 1                    ; 'SCNDEV' & 'PSTOP' USE.
0549  = 0004      GNUMB   DS 4                    ; GRAPHICS WORKING STORAGE & "XACCPT' TEMPORARY.
054D  = 0001      USTKP   DS 1                    ; USE STACK POINTER (0 - N*2).
054E  = 0001      ESTKP   DS 1                    ; EXPRESSION STACK POINTER.
054F  = 0001      TRTLON  DS 1                    ; DIVISIBLE TURTLE OFF, ELSE ON.
0550  = 0001      TRTSNS  DS 1                    ; VISIBLE TURTLE SENSOR STATE.
0551  = 0001      LETTRSZ DS 1                    ; TEXT LETTER SIZE: 0,1 OR 2.
0552  = 0001      SPLTSC  DS 1                    ; 0=FULL GRAPHICS, $10 = SPLIT SCREEN.
      = 000A      NMBFSZ  =  5*2                  ; 'MNYNMS' BUFFER SIZE.
0553  = 000A      NMSBF   DS NMBFSZ
055D  = 0001      SPEED   DS 1                    ; SPEED CONTROL.
055E  = 0001      EDGRUL  DS 1                    ; TURTLE EDGE RULE.
055F  = 0001      TRYPOS  DS 1                    ; VISIBLE TURTLE Y POSITION.
0560  = 0001      ORIENT  DS 1                    ; VISIBLE TURTLE ORIENTATION.
0561  = 0002      XC      DS 2                    ; SCREEN CENTER X.
0563  = 0002      YC      DS 2                    ; SCREEN CENTER Y.
0565  = 0001      CSTATE  DS 1                    ; CONSOLE KEY READ STATE.
0566  = 0001      ATRTYP  DS 1                    ; 'NAME' ATTRIBUTE FOR 'IFIND'.
0567  = 0001      DMPTYP  DS 1                    ; ATTRIBUTE FOR DUMP CODE.
0568  = 0001      TKNTYP  DS 1                    ; TOKENIZED COMMAND
0569  = 0001      LSTKN   DS 1                    ; TOKEN FROM PREVIOUS STATEMENT FOR ': CONTINUATION'.
056A  = 0001      TKNOFF  DS 1                    ; OFFSET PAST COMMAND.
056B  = 0030      USESTK  DS USTKSZ               ; USE STACK.
059B  = 0001      FCOLOR  DS 1                    ; 'FLOOD' COLOR
059C  = 0001      FLDCLR  DS 1                    ; FIELD COLOR TO BE FLOODED.
059D  = 0001      MSKTMP  DS 1                    ; TEMP MASKED DATA.
059E  = 0001      ROWFLG  DS 1                    ; ROW FLAG.
059F  = 0001      COLFLG  DS 1                    ; COLUMN FLAG.
05A0  = 0001      SAVROW  DS 1                    ; SAVED STARTING ROW.
05A1  = 0002      SAVCOL  DS 2                    ; SAVED STARTING COLUMN.
05A3  = 0002      LFTCOL  DS 2                    ; LEFT COLUMN VALUE.
05A5  = 0002      NEWLC   DS 2                    ; NEW LEFT COLUMN.
05A7  = 0002      RGTCOL  DS 2                    ; RIGHT COLUMN VALUE.
05A9  = 0002      NEWRC   DS 2                    ; RIGHT COLUMN.
05AB  = 0001      MAXROW  DS 1                    ; MAXIMUM ROW VALUE.
05AC  = 0002      MAXCOL  DS 2                    ; MAXIMUM COLUMN VALUE.
05AE  = 0002      MLTTMP  DS 2                    ; MULTIPLY TEMP.
05B0  = 0001      SHFAMT  DS 1                    ; SHIFT AMOUNT.
05B1  = 0001      DMASK   DS 1
05B2  = 0001      FINEFG  DS 1                    ; 0 = COARSE SCROLL, -1 = FINE.
05B3  = 0002      CETEMP  DS 2                    ; 'COMPRS'/'EXPAND' TEMPORARY.
05B5  = 0001      LFCOL   DS 1                    ; T: LEFT MOST COLUMN.
05B6  = 0001      RGCOL   DS 1                    ; T: RIGHT MOST COLUMN.
05B7  = 0001      PENNUM  DS 1                    ; PEN NUMBER.
05B8  = 0001      PENCOL  DS 1                    ; PEN COLOR.
05B9  = 0001      NCOLRS  DS 1                    ; NUMBER OF COLORS ALLOWED.
05BA  = 0001      NXTCLR  DS 1                    ; NEXT AVAILA8LE COLOR SLOT.
05BB              PNCLRS                          ; PEN COLORS.
05BB  = 0001      BAKCLR  DS 1                    ; BACKGROUND COLOR.
05BC  = 0008              DS 8                    ; FOREGROUND COLORS.
05C4  = 0001      TRTCOL  DS 1                    ; TURTLE COLOR.
05C5  = 0001      RBTON   DS 1                    ; 0=ROBOT TURTLE OFF, ELSE ON.
05C6  = 0001      RBTSNS  DS 1                    ; ROBOT SENSOR STATE.
05C7  = 0001      RBTCMD  DS 1                    ; INTERNAL ROBOT COMMAND.
05C8  = 0002      RBTPRM  DS 2                    ; INTERNAL ROBOT PARAMETER.
05CA  = 0001      INDENT  DS 1                    ; AUTO INDENT.
05CB  = 0001      SCTEMP  DS 1                    ; 'SETCLR' TEMP.
05CC  = 0001      PRTEMP  DS 1                    ; 'PRCLNM' TEMP.
05CD  = 0002      WALLS   DS 2                    ; WALL SELECTION DATA.
05CF  = 0002      GCOL    DS 2                    ; TURTLE COLUMN POSITION.
05D1  = 0001      GROW    DS 1                    ; TURTLE ROW POSITION.
05D2  = 0002      GANGLE  DS 2                    ; TURTLE THETA.
05D4  = 0001      GROPR   DS 1                    ; GRAPHICS OPERATION TYPE.
05D5  = 0001      HITWLL  DS 1                    ; 0 = NO WALL HIT, ELSE WALL HIT.
05D6  = 0001      HITEDG  DS 1                    ; 0 = NO EDGE HIT, ELSE EDGE HIT.
05D7  = 0001      HALTFG  DS 1                    ; NON-ZERO = HALT AT EDGE.
05D8  = 0001      GRTEMP  DS 1                    ; 'GREAD' TEMP.
05D9  = 0001      TUFLAG  DS 1                    ; TURTLE PARAMETER UPDATE INTERLOCK.
05DA  = 0001      LITMAT  DS 1                    ; NON-ZERO = LITERAL MATCH.
05DB  = 0001      NOPLOT  DS 1                    ; NON-ZERO = DON'T PUT POINT.
05DC  = 0002      DSISAV  DS 2                    ; VALUE OF ORIGINAL 'DOSINI'.
05DE  = 0002      DSVSAV  DS 2                    ; VALUE OF ORIGINAL 'DOSVEC.
05E0  = 0001      DMASAV  DS 1                    ; 'DMACT' SAVE VALUE FOB TV ON/OFF.
      = 011F      SPARES  = $700-*                ; *** THIS HAD BETTER BE POSITIVE ***

05E1  = BC00              ORG $BC00
BC00  = 00FF      TEXBUF  DS TEXLNG+1    ; TEXT EXPRESSION BUFFER.
BCFF  = 0001              DS 1           ; ONE EXTRA LEADING BLANK FOR AUTO-IN.
BD00  = 007B      COMBUF  DS LINLNG+1    ; COMMAND INPUT BUFFER.
BD7B  = 0100      ACCBUF  DS 256         ; ACCEPT BUFFER.
BE7B  = 0101      NAMBUF  DS 257         ; STRING NAME BUFFER.

                  ;
                  ; NOTE: THE USE OF THE TERM '(BRA)' IN A COMMENT INDICATES THAT THE
                  ; PARTICULAR BRANCH INSTRUCTIONS USED WILL ALWAYS BRANCH IN THE
                  ; PARTICULAR CIRCUMSTANCES, THE BRANCH IS SUPPOSED TO BE A TWO BYTE
                  ; JUMP.
                  ;

                  ; POWER-UP ROUTINE AND INITIALIZATION

BF7C  = 7700              ORG $7700

7700              PILLOW                          ; PILOT LOW ADDRESS
7700              TPBUFF                          ;
      = 770C      TVBUFF  = TPBUFF+12             ; VISIBLE REGION.
      = 7705      TRBUFF  = TVBUFF-7              ; INCLUDES UNDERFLOW.


7700  = 7800              ORG TPBUFF+256          ; TURTLE REP. BUFFER.

      = 0000              IF      DOS
   -                      LDA     #0              ; CLEAR COLDSTART FLAG (SEE 'XDOS').
   -                      STA     COLDST
   -                      JMP     MLE             ; RETURN FROM DOS.
                          ENDIF

7800                      PROC
7800  A508        PILINI  LDA     WARMST          ; WARM START?
7802  D015 ^7819          BNE     :PI020          ; YES.

7804  A50C                LDA     DOSINI          ; SAVE ORIGINAL 'DOSINI'.
7806  8DDC05              STA     DSISAV
7809  A50D                LDA     DOSINI+1
780B  8DDD05              STA     DSISAV+1

780E  A900                LDA     # LOW PILINI    ; PLUG IN NEW 'DOSINI'.
7810  850C                STA     DOSINI
7812  A978                LDA     # HIGH PILINI
7814  850D                STA     DOSINI+1

      = 0000              IF      DOS
   -                      LDA     DOSVEC          ; SAVE ORIGINAL 'DOSVEC'.
   -                      STA     DSVSAV
   -                      LDA     DOSVEC+1
   -                      STA     DSVSAV+1
                          ENDIF

7816  4C1C78              JMP     :PI030

7819  202578      :PI020  JSR     GODOS           ; PERFORM DOS INIT.

781C  A9C3        :PI030  LDA     # LOW MLE       ; CHANGE 'DOSVEC' FOR PILOT ENTRY.
781E  850A                STA     DOSVEC
7820  A978                LDA     # HIGH MLE
7822  850B                STA     DOSVEC+1
7824  60                  RTS

7825  6CDC05      GODOS   JMP     (DSISAV)        ; 2ND HALF OF JSR (DSISAV).

7828                      PROC
7828  A906        INIT    LDA     #EPUTC-IOVBAS   ; ESTABLISH 'CHOT' DESTINATION AS 'E:'
782A  8D3005              STA     CDEST

782D  A508                LDA     WARMST          ; WARM START?
782F  D037 ^7868          BNE     :INI15          ; YES?

7831  A280                LDX     #$80            ; CLEAR UPPER HALF OF PAGE ZERO.
7833  A900                LDA     #0

7835  9500        :INI10  STA     0,X
7837  E8                  INX
7838  D0FB ^7835          BNE     :INI10          ; CONTINUE TILL PAGE WRAP POINT.

783A  A94C                LDA     #$4C            ; PUT JMP OP-CODE IN JUMP VECTORS.
783C  8D0705              STA     XJUMP+0
783F  8D0A05              STA     GJUMP+0
7842  8D0D05              STA     SJUMP+0

7845  A916                LDA     #$16            ; AUTO-NUMBER SCREEN = DARK YELLOW
7847  8586                STA     ACOLR2
7849  A900                LDA     #$00            ; AUTO-NUMBER LETTERS = BLACK.
784B  8587                STA     ACOLR1

      = 0000              IF      FALSE
   -                      LDA     # LOW PRGEND    ; SET 'MEMLO' AFTER END OF PROGRAM.
   -                      STA     MEMLO
   -                      LDA     # HIGH PRGEND
   -                      STA     MEMLO+1
                          ENDIF

784D  ADE702              LDA     MEMLO           ; ESTABLISH MEMORY LIMITS FOR ALLOCATION.
7850  85AE                STA     S1L             ; ... & PROGRAM STORAGE AREA.
7852  ADE802              LDA     MEMLO+1
7855  85AF                STA     S1L+1
7857  20C087              JSR     CLRPRG

785A  ADE502              LDA     MEMHI           ; ALSO FOR STRING STORAGE AREA.
785D  85B4                STA     S2H
785F  85B2                STA     S2L
7861  ADE602              LDA     MEMHI+1
7864  85B5                STA     S2H+1
7866  85B3                STA     S2L+1

7868  A2B4        :INI15  LDX     # HIGH PILVBL   ; INTERCEPT VBLANKS.
786A  A091                LDY     # LOW PILVBL
786C  A907                LDA     #7              ; VVBLKD.
786E  205CE4              JSR     SETVBV

7871  A900                LDA     #0              ; ZERO ...
7873  8D3205              STA     LOADFG          ; ... LOAD FLAG ...
7876  8D3505              STA     TRACE           ; ... TRACE FLAG ...
7879  8D3605              STA     AUTOIN          ; ... AUTO-INPUT FLAG ...
787C  8D1D05              STA     AUX1            ; ... I/O AUX1 ...
787F  8D1E05              STA     AUX2            ; ... I/O AUX2 ...
7882  85FE                STA     MATCHF          ; ... & MATCH RESULT.
7884  8D1005              STA     CTABAT          ; ... LAST COMMAND ATTRIBUTES.
7887  8DC505              STA     RBTON           ; ... ROBOT TURTLE.
788A  8D5D05              STA     SPEED           ; FULL SPEED.
788D  8DB205              STA     FINEFG          ; COARSE SCROLLING.
7890  8DE005              STA     DMASAV

7893  A97B                LDA     # LOW ACCBUF    ; SET ACCEPT BUFFER POINTER.
7895  8588                STA     ACLN
7897  A9BD                LDA     # HIGH ACCBUF
7899  8589                STA     ACLN+1
789B  20729F              JSR     NULACC          ; SET ACCEPT BUFFER TO NULL.

789E  A900                LDA     # LOW TEXBUF    ; SETUP TEXT EXPRESSION BUFFER POINTER.
78A0  858C                STA     TELN
78A2  A9BC                LDA     # HIGH TEXBUF
78A4  858D                STA     TELN+1
78A6  A920                LDA     #' '            ; LEADING BLANK FOR AUTO-IN.
78A8  8DFFBC              STA     COMBUF-1

78AB  20E1A5              JSR     TRTINI          ; INITIALIZE VISIBLE TURTLE STUFF.
78AE  2050B3              JSR     PBINIT          ; ... ROBOT TURTLE ('OFF' IN 'MLE').
78B1  209E98              JSR     REMDEV          ; REMOVE DEVICE ASSIGNMENTS FROM STRING LIST.
78B4  20F494              JSR     TXOPEN          ; OPEN E: & RECAPTURE GRAPHICS REGION IF NECESSARY.

78B7  A508                LDA     WARMST          ; WARMSTART?
78B9  D005 ^78C0          BNE     :INI30          ; YES.

78BB  A917                LDA     #SIGNON         ; GENERATE SIGN-ON MESSAGE.
78BD  20FFB4              JSR     MESSOT

78C0  4C2CB5      :INI30  JMP     RDYMES          ; GENERATE "READY" MESSAGE & RETURN.

78C3                      PROC
                  ;
                  ; MAIN LOOP FOR PILOT INTERPRETER.
                  ;
                  ;
                  ; POWER-UP ANO RESET ENTRY.
                  ;
78C3  A2FF        MLE     LDX     #$FF            ; INITIALIZE STACK POINTER.
78C5  9A                  TXS

78C6  A970                LDA     # HIGH $7000    ; NEW TOP OF MEMORY.
78C8  856A                STA     RAMTOP
78CA  A900                LDA     #0              ; CLEAR ESSENTIALS FOR EOPEN CALL.
78CC  8D1D05              STA     AUX1
78CF  8D1E05              STA     AUX2
78D2  8D1405              STA     GRFLAG
78D5  8D5105              STA     LETTRSZ
78D8  8DB205              STA     FINEFG
78DB  208E96              JSR     EOPEN           ; MOVE SCREEN DOWN.

78DE  8E4305              STX     NOCONT          ; NO CONTINUATION.

78E1  202878              JSR     INIT            ; INITIALIZE REST OF ENVIRONMENT

                  ; *** EXTERNAL ENTRY POINT ***

78E4  A93C        MLRES   LDA     #CASSOF         ; CASSETTE MOTOR OFF
78E6  8D02D3              STA     PACTL
78E9  20B49F              JSR     AUDCLR          ; CLEAR AUDIO REGISTERS

78EC  A900        MLRES2  LDA     #0              ; RESET ...
78EE  85FF                STA     RUN             ; ... RUN FLAG ...
78F0  8D4505              STA     SGLSTP          ; ... SINGLE STEP ...
78F3  8DFE02              STA     DSPFLG          ; ... DISPLAY FLAG ...
78F6  8DB602              STA     INVFLG          ; ... INVERT VIDEO FLAG ...
78F9  8D0405              STA     IOEDIS          ; ... & ERROR STOP DISABLE FLAG.

78FC  A9E1                LDA     # LOW XTYPE     ; MAKE ':' COMMAND = 'T:'.
78FE  8D0805              STA     XJUMP+1
7901  A983                LDA     # HIGH XTYPE
7903  8D0905              STA     XJUMP+2
7906  8D0605              STA     EXECF           ; CONDITION FLAG = TRUE.

                  ; *** EXTERNAL ENTRY POINT ***

7909  A900        MLLOAD  LDA     # LOW COMBUF    ; RE-ESTABLISH CONSOLE BUFFER INPUT.
790B  8580                STA     INLN
790D  A9BD                LDA     # HIGH COMBUF
790F  8581                STA     INLN+1
7911  20007B      MLOOP   JSR     GETCOM          ; GET A COMMAND INPUT.
7914  D07A ^7990          BNE     :ML090          ; ERROR (SKIP BRANCH).

                  ; NOTE: THE Y REGISTER IS ASSUMED TO CONTAIN THE INDEX TO 'INLN'
                  ;       THROUGHOUT THIS ROUTINE.  ALL CALLED ROUTINES WILL BE
                  ;       RESPONSIBLE POR MAINTAINING ITS INTEGRITY.


7916  AD3205              LDA     LOADFG          ; LOADING?
7919  D00C ^7927          BNE     :ML020          ; YES.

791B  A5FF                LDA     RUN             ; RUN MODE?
791D  D03B ^795A          BNE     :ML070          ; YES.

791F  AD3605              LDA     AUTOIN          ; AUTO-INPUT MODE?
7922  F003 ^7927          BEQ     :ML020          ; NO.

7924  4C9D79              JMP     :ML100          ; YES.

7927  AD4405      :ML020  LDA     CONKEY
792A  2901                AND     #STRTKY         ; START KEY?
792C  F017 ^7945          BEQ     :ML030          ; NO.

792E  AD4405              LDA     CONKEY          ; RESET THE KEY FLAG.
7931  29FE                AND     #$FF-STRTKY
7933  8D4405              STA     CONKEY

7936  AD4305              LDA     NOCONT          ; CAN WE CONTINUE?
7939  F003 ^793E          BEQ     :ML025          ; YES.

793B  201185              JSR     XRN010          ; NO -- START AT BEGINNING.

793E  CE4505      :ML025  DEC     SGLSTP          ; YES -- SET FLAG.
7941  C6FF                DEC     RUN             ; SET TO RUN MODE.
7943  D0CC ^7911          BNE     MLOOP           ; (BRA).


7945  20D39E      :ML030  JSR     SCNLBL          ; SCAN OVER LABEL IF PRESENT
7948  F007 ^7951          BEQ     :ML040          ; YES -- SAW A VALID LABEL.

794A  B180                LDA     (INLN),Y        ; CHECK FOR LINE NUMBER.

794C  20839E              JSR     CNUMBR          ; NUMBERED LINE?
794F  905E ^79AF          BCC     :ML110          ; YES -- EDIT MODE.

                  ; UN-NUMBERED LINE -- IMMEDIATE EXECUTION

7951  A240        :ML040  LDX     #CTIMM          ; SETUP FOR IMMEDIATE MODE COMMANDS.
7953  20AB7B              JSR     SYCMND          ; IMMEDIATE MODE -- SYNTAX CHECK CODE.
7956  D038 ^7990          BNE     :ML090          ; ERROR -- DON'T EXECUTE THE COMMAND

7958  F033 ^798D          BEQ     :ML085          ; (BRA).

                  ; LINE FROM STORAGE -- 'RUN' MODE

795A  AD4405      :ML070  LDA     CONKEY          ; CONSOLE KEY PRESSED?
795D  2904                AND     #OPTKEY         ; OPTION KEY?
795F  F010 ^7971          BEQ     :ML080          ; NO.

7961  AD3505              LDA     TRACE           ; YES -- TOGGLE THE TRACE.
7964  4901                EOR     #KON
7966  8D3505              STA     TRACE

7969  AD4405              LDA     CONKEY          ; RESET THE KEY FLAG.
796C  29FB                AND     #$FF-OPTKEY
796E  8D4405              STA     CONKEY

7971  AD3505      :ML080  LDA     TRACE           ; TRACE EXECUTION?
7974  0D4505              ORA     SGLSTP
7977  F014 ^798D          BEQ     :ML085          ; NO.

7979  20BB96              JSR     TSTMOD          ; CHECK SCREEN MODE.
797C  2905                AND     #TXSL+GRSS      ; TEXT OUPUT O.K.?
797E  D003 ^7983          BNE     :ML082          ; YES.

7980  20F494              JSR     TXOPEN          ; NO -- OPEN TEXT SCREEN.

7983  A918        :ML082  LDA     #TRCMES         ; PRINT TRACE LINE HEADER.
7985  20FFB4              JSR     MESSOT
7988  A000                LDY     #INLN-DTAB      ; PRINT SOURCE STATEMENT.
798A  20229F              JSR     PSF

                  ; COMMON CODE 'IMMEDIATE' AND 'RUN'

798D  20E27B      :ML085  JSR     EXCMND          ; EXECUTE THE COMMAND.
7990  D06E ^7A00  :ML090  BNE     :ML155          ; RUN-TIME ERROR (SKIP BRANCH POINT).

7992  AD4505              LDA     SGLSTP          ; SINGLE STEP?
7995  F003 ^799A          BEQ     :ML095          ; NO.

7997  4CEC78              JMP     MLRES2          ; YES -- RETURN TO IMMEDIATE MODE.

799A  4C1179      :ML095  JMP     MLOOP           ; GET NEXT COMMAND.

                  ; AUTO-INPUT MODE -- SUPPLY THE LINE NUMBER AND ONE EXTRA LEADING BLANK.

799D  A5FA        :ML100  LDA     ALINE           ; SUPPLY THE LINE NUMBER.
799F  85B8                STA     NUMBER
79A1  A5FB                LDA     ALINE+1
79A3  85B9                STA     NUMBER+1

79A5  A200                LDX     #INLN-DTAB
79A7  20129D              JSR     DDCRI           ; ONE EXTRA LEADING BLANK.
79AA  E683                INC     INLN+3

79AC  4CB279              JMP     :ML112

                  ; NUMBERED LINE INPUT -- EDIT MODE.

79AF  206E81      :ML110  JSR     ATOM            ; CONVERT LINE NUMBER TO BINARY IN 'NUMBER'.

79B2  8482        :ML112  STY     INLN+2          ; SAVE INPUT LINE POINTER.

79B4  A238                LDX     #NUMBER-DTAB
79B6  AD3205              LDA     LOADFG          ; SUPPLY LINE NUMBER IF 'APPEND'.
79B9  C903                CMP     #KAPPND
79BB  D005 ^79C2          BNE     :ML120

79BD  A07A                LDY     #ALINE-DTAB
79BF  20459A              JSR     DMOVI

79C2  206B94      :ML120  JSR     CHKLN           ; CHECK LINE # FOR RANGE.
79C5  B05F ^7A26          BCS     :ML200          ; OUT OF RANGE.

79C7  A900                LDA     #0              ; CLEAR USE STACK ON INSERT/DELETE.
79C9  8D4D05              STA     USTKP

79CC  A9FF                LDA     #$FF            ; ALTER PROGRAM -- NO CONTINUATION.
79CE  8D4305              STA     NOCONT

79D1  A5B9                LDA     NUMBER+1        ; SAVE LINE NUMBER ...
79D3  85DC                STA     LINENO          ; ... IN INVERTED FORM (STRING NAME).
79D5  A5B8                LDA     NUMBER
79D7  85DD                STA     LINENO+1

79D9  A482                LDY     INLN+2          ; RESTORE INPUT LINE INDEX.
79DB  20D39E              JSR     SCNLBL          ; SKIP OVER LABEL IF PRESENT.
79DE  F019 ^79F9          BEQ     :ML150          ; LABEL FOUND.

79E0  B180                LDA     (INLN),Y        ; CHECK FOR NULL STATEMENT.
79E2  C99B                CMP     #EOL
79E4  D013 ^79F9          BNE     :ML150          ; NON-NULL -- STATEMENT IS TO BE ENTERED.

79E6  AD3605              LDA     AUTOIN          ; AUTO-INPUT MODE?
79E9  F008 ^79F3          BEQ     :ML140          ; NO.

79EB  20167A              JSR     LVAUTO          ; LEAVE AUTO-INPUT MODE.

79EE  A981                LDA     #AUTOXT         ; GENERATE MESSAGE AS WE LEAVE.
79F0  4CC57A              JMP     :ML985

79F3  20E77A      :ML140  JSR     LDELET          ; YES -- DELETE NUMBERED LINE.
79F6  4C1179      :ML145  JMP     MLOOP

79F9  A482        :ML150  LDY     INLN+2          ; RESTORE INPUT LINE POINTER.

79FB  A220                LDX     #CTRUN          ; SETUP FOR RUN MODE COMMANDS.
79FD  20AB7B              JSR     SYCMND          ; SYNTAX CHECK THE STATEMENT.
7A00  D038 ^7A3A  :ML155  BNE     :ML900          ; SYNTAX ERROR (SKIP BRANCH POINT).

7A02  20CE7A              JSR     LINSRT          ; INSERT THE NEW LINE (COMMAND 'TOKENIZED').
7A05  D01F ^7A26          BNE     :ML200          ; NO ROOM FOR NEW LINE.

7A07  A27A                LDX     #ALINE-DTAB     ; INCREMENT AUTO-INPUT LINE #.
7A09  A07C                LDY     #AINC-DTAB      ; (EVEN IF NOT IN AUTO-INPUT MODE).
7A0B  20329C              JSR     DADDI

7A0E  AD3605              LDA     AUTOIN          ; AUTO-INPUT MODE?
7A11  F0E3 ^79F6          BEQ     :ML145          ; NO -- GET NEXT COMMAND.
7A13  4C0979              JMP     MLLOAD          ; YES -- ADJUST 'INLN' FOR 'LEADING BLANK'.

7A16  A200        LVAUTO  LDX     #0              ; RESET AUTO-INPUT MODE.
7A18  8E3605              STX     AUTOIN

7A1B  A284                LDX     #CBLUE          ; RESTORE NORMAL SCREEN COLOR.
7A1D  8EC602              STX     COLOR0+2
7A20  A21A                LDX     #CYELLO
7A22  8EC502              STX     COLOR0+1
7A25  60                  RTS

                  ; NO ROOM FOR LINE OR LINE # OUT OF RANGE.

7A26  48          :ML200  PHA                     ; SAVE ERROR CODE.
7A27  AD3205              LDA     LOADFG          ; LOAD IN PROGRESS?
7A2A  F00A ^7A36          BEQ     :ML210          ; NO.

7A2C  A900                LDA     #0              ; ABORT LOAD.
7A2E  8D3205              STA     LOADFG
7A31  A230                LDX     #IOCB3          ; CLOSE FILE.
7A33  203F97              JSR     DCLOSE

7A36  68          :ML210  PLA                     ; RESTORE ERROR CODE.
7A37  20167A              JSR     LVAUTO          ; LEAVE AUTO-INPUT MODE & FALL INTO 'PSTOP'.

                  ; SYNTAX/RUN-TIME ERROR PROCESSOR

                  ; *** EXTERNAL ENTRY POINT ***

                  ;       A = ERROR CODE
                  ;       Y = INDEX TO ERROR IN STATEMENT.

7A3A              :ML900
7A3A  A2FF        PSTOP   LDX     #$FF            ; RE-INIT STACK POINTER.
7A3C  9A                  TXS
7A3D  8EFE02              STX     DSPFLG          ; SET DISPLAY FLAG.

7A40  8C1205              STY     SAVYR           ; SAVE INDEX TO ERROR.
7A43  85B8                STA     NUMBER          ; SAVE ERROR NUMBER.

7A45  20BB96              JSR     TSTMOD          ; CHECK SCREEN MODE.
7A48  2905                AND     #TXSL+GRSS      ; TEXT OUTPUT O.K.?
7A4A  D003 ^7A4F          BNE     :ML920          ; YES.

7A4C  20F494              JSR     TXOPEN          ; NO -- OPEN TEXT SCREEN.

7A4F  A906        :ML920  LDA     #EPUTC-IOVBAS   ; RE-ESTABLISH 'E:' AS 'CHOT' OUTPUT.
7A51  8D3005              STA     CDEST
7A54  20989F              JSR     NEWLIN

7A57  A5FF                LDA     RUN             ; IF IMMEDIATE ...
7A59  0583                ORA     INLN+3          ; ... & EMPTY INPUT LINE ...
7A5B  F06E ^7ACB          BEQ     :ML990          ; ... THEN IGNORE ERROR (BREAK).

7A5D  A5B8                LDA     NUMBER
7A5F  C981                CMP     #EOPERR         ; SEE IF ERROR IS END OF PROGRAM.
7A61  F062 ^7AC5          BEQ     :ML985          ; YES -- NO STATEMENT TO PRINT.

7A63  A8                  TAY                     ; (SET CC).
7A64  3012 ^7A78          BMI     :ML947          ; YES -- NO HIGHLIGHTED CHARACTER.

7A66  AC1205              LDY     SAVYR           ; HIGHLIGHT THE ERROR CHARACTER.
7A69  B180                LDA     (INLN),Y
7A6B  8D4805              STA     XXXX            ; SAVE FOR LATER RESTORATION.
7A6E  C99B                CMP     #EOL
7A70  D002 ^7A74          BNE     :ML945

7A72  A920                LDA     #' '             ; REPLACE EOL WITH BLANK.

7A74  4980        :ML945  EOR     #$80            ; INVERT COLOR.
7A76  9180                STA     (INLN),Y

7A78  A5FF        :ML947  LDA     RUN             ; SEE IF RUN OR IMMEDIATE MODE.
7A7A  F008 ^7A84          BEQ     :ML950          ; IMMEDIATE.

7A7C  A000                LDY     #INLN-DTAB
7A7E  20229F              JSR     PSF             ; RUN -- PRINT STORAGE FORMAT.
7A81  4C8D7A              JMP     :ML960

7A84              :ML950
7A84  A900                LDA     #0              ; *** OR DON'T USE 'INLN'+2 AS TEMP STORE ***
7A86  8582                STA     INLN+2

7A88  A200                LDX     #INLN-DTAB      ; IMMEDIATE -- PRINT INPUT LINE.
7A8A  209797              JSR     PRTSTG

7A8D  A5B8        :ML960  LDA     NUMBER          ; WAS THERE A HIGHLIGHTED CHARACTER?
7A8F  300F ^7AA0          BMI     :ML963          ; NO.

7A91  AC1205              LDY     SAVYR           ; RESTORE ORIGINAL CHARACTER.
7A94  AD4805              LDA     XXXX
7A97  9180                STA     (INLN),Y
7A99  C99B                CMP     #EOL            ; WAS IT THE EOL?
7A9B  D003 ^7AA0          BNE     :ML963          ; NO.

7A9D  208294              JSR     CHOT            ; YES -- DO IT NOW.

7AA0  A908        :ML963  LDA     #ASTMES         ; PREFIX MESSAGE WITH '***'.
7AA2  20FFB4              JSR     MESSOT

7AA5  A5B8                LDA     NUMBER
7AA7  C986                CMP     #IOERR          ; I/O ERROR?
7AA9  D00A ^7AB5          BNE     :ML981          ; NO.

7AAB  A4E4                LDY     IOSTAT          ; YES -- BREAK?
7AAD  C080                CPY     #128
7AAF  D004 ^7AB5          BNE     :ML981          ; NO.

7AB1  A987                LDA     #ABTERR         ; YES -- CHANGE ERROR CODE.
7AB3  85B8                STA     NUMBER

7AB5  20FFB4      :ML981  JSR     MESSOT          ; GENERATE ERROR MESSAGE.
7AB8  A5B8                LDA     NUMBER
7ABA  C986                CMP     #IOERR          ; I/O ERROR?
7ABC  D005 ^7AC3          BNE     :ML982          ; NO.

7ABE  A264                LDX     #IOSTAT-DTAB    ; YES -- PRINT ERROR STATUS.
7AC0  20149E              JSR     DECASC

7AC3  A908        :ML982  LDA     #ASTMES         ; APPEND '***' TO END OF MESSAGE.

                  ; *** EXTERNAL ENTRY POINT FROM 'MLOOP' ***

7AC5  20FFB4      :ML985  JSR     MESSOT
7AC8  20989F              JSR     NEWLIN

7ACB  4CE478      :ML990  JMP     MLRES           ; GET NEXT COMMAND.

                  ; LINE INSERT AND DELETE ROUTINES


7ACE                      PROC

                  ;
                  ; LINSRT -- INSERT NUMBERED LINE TO STATEMENT LIST
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'LINENO' = LINE # (BINARY)
                  ;       'INLN' POINTS TO STATEMENT TO INSERT
                  ;       'TKNTYP' = TOKEN
                  ;       'TKNOFF' = OFFSET PAST COMMAND IN SOURCE STATEMENT.
                  ;
                  ;       JSR     LINSRT
                  ;       BNE     NO ROOM IN MEMORY OR OTHER PROBLEM
                  ;
7ACE  20ED7A      LINSRT  JSR     NUMNAM          ; SETUP 'LINENO' AS STRING NAME.

7AD1  A242                LDX     #DP-DTAB        ; SETUP STRING AT A POINTER.
7AD3  A000                LDY     #INLN-DTAB
7AD5  203B9A              JSR     PMOVE

7AD8  38                  SEC                     ; OFFSET PAST COMMAND =
7AD9  AD6A05              LDA     TKNOFF          ; ... 'TKNOFF'.
7ADC  E582                SBC     INLN+2          ; ... - 'INLN+2'.
7ADE  18                  CLC
7ADF  6906                ADC     #6              ; ... + 6.
7AE1  8D6A05              STA     TKNOFF

7AE4  4C0599              JMP     SINSRT          ; INSERT LINE & RETURN WITH CC SET.


7AE7                      PROC
                  ;
                  ; LDELET -- NUMBERED LINE DELETE FROM STATEMENT LIST
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'LINENO' = LINE * (BINARY)
                  ;
                  ;       JSR     LDELET
                  ;       BNE     LINE NOT FOUND OR OTHER PROBLEM
                  ;
7AE7  20ED7A      LDELET  JSR     NUMNAM          ; SETUP 'LINENO' AS STRING NAME.
7AEA  4CEC98              JMP     SDELET          ; DELETE LINE & RETURN WITH CC SET.


7AED                      PROC
                  ;
                  ; NUMNAM -- SETUP 'LINENO' AS STRING NAME & SETUP ACCESS TO STATEMENT LIST.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       JSR     NUMNAM
                  ;
                  ;       'ATRTYP' SET FOR LINE #
                  ;
7AED  A9DC        NUMNAM  LDA     # LOW LINENO
7AEF  85BE                STA     NP
7AF1  A900                LDA     # HIGH LINENO
7AF3  85BF                STA     NP+1
7AF5  A900                LDA     #0
7AF7  85C0                STA     NP+2
7AF9  A902                LDA     #2
7AFB  85C1                STA     NP+3
7AFD  4C9F9E              JMP     STMLST          ; SETUP TO ACCESS STATEMENT LIST & RETURN.


7B00                      PROC
                  ;
                  ; GETCOM -- GET A COMMAND LINE FOR THE MAIN LOOP
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'LOADFG' = 0 IF NOT LOADING FROM DEVICE, ELSE LOADING.
                  ;       'RUN' = 0 IF IMMEDIATE MODE, ELSE RUN MODE.
                  ;       'NXTLN' POINTS TO NEXT RUN MODE LINE.
                  ;
                  ;       JSR     GETCOM
                  ;       BNE     ERROR (A = ERROR NUMBER)
                  ;
                  ;       'INLN' POINTS TO NEW COMMAND LINE.
                  ;       Y = INDEX TO START OF STATEMENT.
                  ;       'NXTLN' POINTS TO NEXT RUN MODE LINE.
                  ;
                  ;       IF 'RUN', THEN
                  ;
                  ;       'TKNTYP' = TOKENIZED COMMAND
                  ;       'TKNOFF' = OFFSET PAST COMMAND IN STATEMENT STORAGE.
                  ;
7B00  AD3205      GETCOM  LDA     LOADFG          ; LOADING FROM DEVICE?
7B03  D041 ^7B46          BNE     :GC200          ; YES.

7B05  A5FF                LDA     RUN             ; RUN MODE?
7B07  F031 ^7B3A          BEQ     :GC100          ; NO -- IMMEDIATE.

7B09  207E9F      :GC010  JSR     ABRTCK          ; YES -- CHECK FOR OPERATOR ABORT.

7B0C  A200                LDX     #INLN-DTAB      ; GET NEXT STATEMENT ADDRESS.
7B0E  A004                LDY     #NXTLN-DTAB
7B10  20459A              JSR     DMOVI

7B13  A000                LDY     #0              ; GET & SAVE LINE END INDEX.
7B15  B180                LDA     (INLN),Y
7B17  8583                STA     INLN+3

7B19  A030                LDY     #S1H-DTAB       ; END OF PROGRAM?
7B1B  20159C              JSR     DCMPI
7B1E  D006 ^7B26          BNE     :GC020          ; NO -- KEEP TRUCKIN'.

7B20  A981                LDA     #EOPERR         ; RETURN WITH INDICATOR.
7B22  8D4305              STA     NOCONT          ; NO CONTINUATION.
7B25  60                  RTS

7B26              :GC020
                  ; *S*   LDX     #INLN-DTAB
7B26  20869A              JSR     SATTR           ; 'ATTRIBUTE'
7B29  8D6805              STA     TKNTYP          ; AS ADVERTISED.
7B2C  C8                  INY
7B2D  B1A1                LDA     (TEMP),Y
7B2F  8D6A05              STA     TKNOFF          ; AS ADVERTISED.
7B32  A204                LDX     #NXTLN-DTAB     ; POINT TO NEXT LINE.
7B34  20AA9A              JSR     SNXTI
7B37  A900                LDA     #0              ; SET CC FOR RETURN.
7B39  60                  RTS

                  ; GET A LINE FROM THE CONSOLE.

7B3A              :GC100
7B3A  A900                LDA     #0              ; CLEAR LINE LENGTH FOR "BREAK".
7B3C  8583                STA     INLN+3
7B3E  A200                LDX     #INLN-DTAB      ; GET AN INPUT LINE FROM CONSOLE.
7B40  20B194              JSR     GETLIN
7B43  A000                LDY     #0              ; SET INDEX TO START OF STATEMENT (CC TOO).
7B45  60                  RTS

                  ; GET DATA FROM DEVICE ASSIGNED TO IOCB 3.

7B46  86A1        :GC200  STX     TEMP            ; SAVE REGISTERS.

7B48  A580        :GC205  LDA     INLN            ; SETUP BUFFER ADDRESS.
7B4A  8D7403              STA     IOCB3+ICBAL
7B4D  A581                LDA     INLN+1
7B4F  8D7503              STA     IOCB3+ICBAH

7B52  A905                LDA     #GETR           ; GET RECORD COMMAND.
7B54  8D7203              STA     IOCB3+ICCOM

7B57  A979                LDA     # LOW LINLNG-1  ; SETUP MAXIMUM LINE LENGTH.
7B59  8D7803              STA     IOCB3+ICBLL
7B5C  A9FF                LDA     # HIGH LINLNG-1
7B5E  8D7903              STA     IOCB3+ICBLH

7B61  A230                LDX     #IOCB3          ; GET RECORD.
7B63  2056E4              JSR     CIO

7B66  AD7803              LDA     IOCB3+ICBLL     ; PUT START/END INDICES IN POINTER.
7B69  8583                STA     INLN+3
7B6B  A900                LDA     #0
7B6D  8582                STA     INLN+2

7B6F  C000                CPY     #0              ; ERROR?
7B71  1029 ^7B9C          BPL     :GC250          ; NO.

7B73  A900                LDA     #0              ; THAT OR END-OF-FILE.
7B75  8D3205              STA     LOADFG          ; STOP LOADING IN EITHER CASE.

7B78  C088                CPY     #$88            ; END OF FILE?
7B7A  D01D ^7B99          BNE     :GC220          ; NO.

7B7C  203F97              JSR     DCLOSE          ; YES -- CLOSE DEVICE.

7B7F  A5FF                LDA     RUN             ; IS THE USER PROGRAM RUNNING?
7B81  F010 ^7B93          BEQ     :GC210          ; NO -- IMMEDIATE LOAD OR LOAO ERROR.

7B83  A900                LDA     #0              ; CONTINUE O.K.
7B85  8D4305              STA     NOCONT

7B88  A5AE                LDA     S1L             ; SETUP TO RUN PROGRAM LOADED.
7B8A  8584                STA     NXTLN
7B8C  A5AF                LDA     S1L+1
7B8E  8585                STA     NXTLN+1
7B90  4C097B              JMP     :GC010          ; (TOO FAR FOR 'RELATIVE').

7B93  202CB5      :GC210  JSR     RDYMES          ; GENERATE "READY" MESSAGE.
7B96  4CE478              JMP     MLRES           ; GRACEFUL TERMINATION OF LOAD.

7B99  4C2897      :GC220  JMP     DOP005          ; ABORT LOAD OPERATION.

7B9C  A000        :GC250  LDY     #0              ; ACCEPT ONLY NUMBERED LINES.
7B9E  20139F              JSR     SLB
7BA1  20839E              JSR     CNUMBR
7BA4  B0A2 ^7B48          BCS     :GC205          ; NOT NUMBERED--IGNORE.

7BA6  A6A1                LDX     TEMP            ; RESTORE REGISTER.
7BA8  A000                LDY     #0              ; SETUP INDEX TO START OF STATEMENT (=0).
7BAA  60                  RTS                     ; RETURN WITH CC SET.


7BAB                      PROC
                  ;
                  ; SYCMND -- SYNTAX CHECK THE COMMAND
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = VALID CCMNAND MODE.
                  ;       'INLN' POINTS TO THE STATEMENT
                  ;       Y = INDEX TO START OP STATEMENT
                  ;
                  ;       JSR     SYCMND
                  ;       BNE     SYNTAX ERROR (A = ERROR CODE)
                  ;
                  ;       'TKNTYP' = TOKENIZED COMMAND.
                  ;          0/#USROFF-1               = COMMAND IS IN 'CDTAB'
                  ;          #USROFF/#USROFF+#USRMAX-1 = COMMAND IS IN 'USRTAB'
                  ;                         'TKNCNT'   = RESERVED FOR ': CONTINUATION'
                  ;                         'TKNNUL'   = RESERVED FOR 'NULL' COMMAND
                  ;       'TKNOFF' = OFFSET PAST COMMAND FROM BEGINNING OF STATEMENT.
                  ;
7BAB  20D39E      SYCMND  JSR     SCNLBL          ; SCAN PAST LABEL IF PRESENT.
7BAE  20139F              JSR     SLB

7BB1  C93A                CMP     #':'            ; COMMAND CONTINUATION?
7BB3  F01D ^7BD2          BEQ     :SC010          ; YES.

7BB5  20F99E              JSR     CHKTRM          ; 'NULL' COMMAND?
7BB8  F01D ^7BD7          BEQ     :SC020          ; YES.

7BBA  A900                LDA     #0              ; RESET EXECUTE FLAG.
7BBC  8592                STA     EXEC

7BBE  20567C              JSR     CMATCH          ; FIND COMMAND.
7BC1  F006 ^7BC9          BEQ     :SC005          ; VALID.

7BC3  C902                CMP     #IVCERR         ; IF NOT IN TABLE, ASSUME 'GR:'.
7BC5  D01A ^7BE1          BNE     :SC099          ; ERROR.

7BC7  A23A                LDX     #CDG-CDTAB      ; CASE: 10 360(HOME;DRAW 10;TURN 1).

7BC9  8E6805      :SC005  STX     TKNTYP          ; TOKENIZE COMMAND.
7BCC  8C6A05              STY     TKNOFF          ; OFFSET PAST COMMAND.
7BCF  4C087C              JMP     EXC100

7BD2  C8          :SC010  INY                     ; MOVE PAST
7BD3  A9FE                LDA     #TKNCNT         ; COMMAND CONTINUATION.
7BD5  D002 ^7BD9          BNE     :SC050          ; (BRA).

7BD7  A9FF        :SC020  LDA     #TKNNUL         ; NULL COMMAND.

7BD9  8D6805      :SC050  STA     TKNTYP
7BDC  8C6A05              STY     TKNOFF

7BDF  A900                LDA     #0              ; SET CC FOR EXIT.

7BE1  60          :SC099  RTS


7BE2                      PROC
                  ;
                  ; EXCMND -- EXECUTE THE COMMAND
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'TKNTYP' = TOKENIZED COMMAND.
                  ;       'TKNOFF' = OFFSET PAST COMMAND.
                  ;
                  ;       JSR     EXCMND
                  ;       BNE     SYNTAX OR RUN-TIME ERROR (A = ERROR CODE).
                  ;
7BE2  AC6A05      EXCMND  LDY     TKNOFF          ; OFFSET PAST COMMAND.
7BE5  A9FF                LDA     #$FF            ; SET EXECUTE FLAG.
7BE7  8592                STA     EXEC

7BE9  AE6805              LDX     TKNTYP          ; TRAP FOR 'RESERVED' TOKENS.
7BEC  E0FE                CPX     #TKNCNT
7BEE  9018 ^7C08          BCC     EXC100          ; NOT 'RESERVED'.
7BF0  D013 ^7C05          BNE     :EC020          ; 'NULL' COMMAND.

                  ; COMMAND CONTINUATION

7BF2  AE6905              LDX     LSTKN           ; USE TOKEN FROM 'LAST' COMMAND.
7BF5  8E6805              STX     TKNTYP

7BF8  E008                CPX     #CLNCNT         ; NO -- CHECK 'CDTAB' SEGMENT.
                                                  ; ('USRTAB' NOT ALLOWED).
7BFA  9004 ^7C00          BCC     :EC010          ; O.K.

7BFC  88                  DEY                     ; POINT TO '!'.
7BFD  A902                LDA     #IVCERR         ; INVALID CONTINUATION.
7BFF  60                  RTS

                  ; COMMAND CONTINUATION IS VALID.

7C00  AD0605      :EC010  LDA     EXECF           ; USE PRIOR 'EXECF'.
7C03  D03F ^7C44          BNE     :EC500          ; EXECUTE COMMAND USING PRIOR 'XJUMP'.

                  ; EXIT FOR 'NULL' COMMAND.

7C05  A900        :EC020  LDA     #0              ; SET CC FOR EXIT.
7C07  60                  RTS

                  ; *** ENTRY FROM 'SYCMND' ***

7C08  200E81      EXC100  JSR     COND            ; PROCESS CONDITION IF PRESENT.
7C0B  A592                LDA     EXEC            ; EXECUTE MODE?
7C0D  F005 ^7C14          BEQ     :EC300          ; NO -- SYNTAX SCAN ONLY.

7C0F  AD0605              LDA     EXECF           ; EXECUTE COMMAND?
7C12  F041 ^7C55          BEQ     :EC900          ; NO -- NORMAL EXIT.

7C14  84AB        :EC300  STY     XTEMP           ; SAVE Y.
7C16  AC6805              LDY     TKNTYP          ; 'USRTAB' OR 'CDTAB'?
7C19  8C6905              STY     LSTKN           ; SAVE TOKEN IN CASE NEXT COMMAND USES
                                                  ; ':-CONTINUATION'.
7C1C  C06C                CPY     #USROFF
7C1E  900F ^7C2F          BCC     :EC400          ; 'CDTAB'.

7C20  98                  TYA                     ; 'NORMALIZE' RELATIVE TO 'USRTAB'.
7C21  38                  SEC
7C22  E96C                SBC     #USROFF
7C24  A8                  TAY
7C25  AD0005              LDA     USRTAB
7C28  85A1                STA     TEMP
7C2A  AD0105              LDA     USRTAB+1
7C2D  D006 ^7C35          BNE     :EC410          ; (BRA).
7C2F  A93E        :EC400  LDA     # LOW CDTAB
7C31  85A1                STA     TEMP
7C33  A980                LDA     # HIGH CDTAB
7C35  85A2        :EC410  STA     TEMP+1
7C37  B1A1                LDA     (TEMP),Y        ; MOVE ADDRESS TO JUMP INSTRUCTION.
7C39  8D0805              STA     XJUMP+1
7C3C  C8                  INY
7C3D  B1A1                LDA     (TEMP),Y
7C3F  8D0905              STA     XJUMP+2
7C42  A4AB                LDY     XTEMP           ; RESTORE INDEX.
7C44  A592        :EC500  LDA     EXEC            ; SET CC FOR X-ROUTINES.
7C46  200705              JSR     XJUMP           ; YES -- EXECUTE (OR SCAN).
7C49  D00A ^7C55          BNE     :EC900          ; ERROR -- RETURN WITH CC SET.
7C4B  20139F              JSR     SLB             ; SKIP ANY BLANKS.
7C4E  20F99E              JSR     CHKTRM          ; STATEMENT TERMINATOR?
7C51  F002 ^7C55          BEQ     :EC900          ; YES -- O.K.
7C53  A902                LDA     #JNKERR         ; JUNK -- ERROR.
7C55  60          :EC900  RTS                     ; RETURN WITH CC SET.


7C56                      PROC
                  ;
                  ; CMATCH -- COMMAND MATCH ROUTINE
                  ;
                  ; ORDER OF SEARCHING:
                  ;
                  ;       1. THE USER EXTENDABLE COMMAND TABLE
                  ;       2. THE GRAPHICS SUBCOMMANDS
                  ;       3. THE INTERNAL COMMAND TABLE
                  ;
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'USRTAB' = ADDRESS OF USER EXTENDABLE COMMAND TABLE (0=NONE).
                  ;                  (OFFSETS ARE RELATIVE TO 'USRTAB').

                  ;        X = IMMEDIATE AND/OR RUN COMMAND' VALID
                  ;        'INLN' POINTS TO SOURCE STATEMENT.
                  ;        Y = INDEX TO START OF COMMAND NAME.
                  ;
                  ;        JSR     CMATCH
                  ;        BNE     NO MATCH IN TABLE (A = ERROR CODE, Y UNCHANGED)
                  ;
                  ;        X = VALUE OF 'CTAB' DATA BYTE FOR ENTRY ('TOKENIZED' COMMAND).
                  ;        X < 'USROFF' (OFFSET IN 'CDTAB').
                  ;        X >= 'USROFF' ('USROFF' + OFFSET IN 'USRTAB').
                  ;        Y = INDEX TO START OF FIELD AFTER COMMAND NAME.
                  ;        'CTABAT' = ATTRIBUTE BITS OF COMMAND.
                  ;
                  ; NOTE: NAME MATCH MUST BE EXACT FOR THE REST OF THE
                  ;       STATEMENT TO BE PROCESSED CORRECTLY. FOR EXAMPLE:
                  ;               "TYPEN:" WILL BE SCANNED AS TY<JUNK>:, NOT
                  ;                                           T<JUNK>N:.
                  ;
7C56  8E1005      CMATCH  STX     CTABAT          ; SAVE VALID COMMAND TYPES.
7C59  84AB                STY     XTEMP           ; SAVE Y REG.
7C5B  AD0005              LDA     USRTAB          ; SELECT 'USRTAB' IF ADDR>255.
7C5E  8590                STA     TABADR
7C60  AD0105              LDA     USRTAB+1
7C63  F018 ^7C7D          BEQ     :CMA10          ; NO USER EXTENDED COMMAND TABLE.

7C65  8591                STA     TABADR+1
7C67  20BD7C              JSR     CMACOM          ; SEARCH 'USRTAB'
7C6A  D011 ^7C7D          BNE     :CMA10          ; NOT IN 'USRTAB'

7C6C  E092                CPX     #USRMAX         ; IS 'USRTAB' TOO LARGE?
7C6E  B00D ^7C7D          BCS     :CMA10          ; YES -- PRETEND COMMAND WAS NOT THERE.

7C70  98                  TYA                     ; CHECK 'ATTRIBUTE'
7C71  2C1005              BIT     CTABAT
7C74  F031 ^7CA7          BEQ     :CMA90          ; WRONG COMMAND TYPE.

                  ; COMMAND IS IN 'USRTAB'

7C76  8A                  TXA                     ; SET 'TOKEN' FOR 'USRTAB'
7C77  18                  CLC
7C78  696C                ADC     #USROFF         ; SET OFFSET TO IDENTIFY TOKEN IN 'USRTAB'.
7C7A  AA                  TAX
7C7B  D023 ^7CA0          BNE     :CMA50          ; (BRA).

                  ; SEARCH GRAPHICS SUBCOMMANDS

7C7D  A4AB        :CMA10  LDY     XTEMP           ; RESTORE INDEX.
7C7F  A204                LDX     #GTABX
7C81  20AB7C              JSR     SBCMAT          ; GRAPHICS SUBCOMMAND?
7C84  D007 ^7C8D          BNE     :CMA20          ; NO.

7C86  A4AB                LDY     XTEMP           ; RESTORE INDEX FOR SYNTAX CHECK.
7C88  A23A                LDX     #CDG-CDTAB      ; TOKENIZE AS 'GR:'.
7C8A  A900                LDA     #0              ; SET CC FOR EXIT.
7C8C  60                  RTS

                  ; SEARCH INTERNAL COMMAND TABLE

7C8D  A901        :CMA20  LDA     # LOW CTAB
7C8F  8590                STA     TABADR
7C91  A97D                LDA     # HIGH CTAB
7C93  8591                STA     TABADR+1
7C95  20BD7C              JSR     CMACOM          ; SEARCH 'CTAB'
7C98  D01E ^7CB8          BNE     :CMA99          ; NOT IN 'CTAB' -- INVALID.

7C9A  98                  TYA
7C9B  2C1005              BIT     CTABAT
7C9E  F007 ^7CA7          BEQ     :CMA90          ; WRONG COMMAND TYPE.

                  ; COMMAND IS IN 'CTAB'

7CA0  8C1005      :CMA50  STY     CTABAT          ; STORE 'ATTRIBUTE'.
7CA3  A900                LDA     #0              ; SET CC FOR EXIT.
7CA5  F011 ^7CB8          BEQ     :CMA99          ; (BRA).

7CA7  A983        :CMA90  LDA     #NRCERR         ; WRONG COMMAND TYPE.
7CA9  D00D ^7CB8          BNE     :CMA99          ; (BRA).

                  ;
                  ; SBCMAT -- SUBCOMMAND MATCH ROUTINE
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = INDEX TO THE SUBCOMMAND TABLE FROM 'SBCTAB'
                  ;       'JNLN' POINTS TO SOURCE STATEMENT.
                  ;       Y = INDEX TO START OF SUBCOMMAND NAME.
                  ;
                  ;       JSR SBCMAT
                  ;       BNE NO MATCH IN TABLE (A = ERROR CODE, Y UNCHANGED)
                  ;
                  ;       X = VALUE OF 'SBCTAB' DATA BYTE FOR ENTRY ('OFFSET' OR 'VALUE')
                  ;       Y = INDEX TO START OF FIELD AFTER COMMAND NAME.
                  ;
7CAB  BD207E      SBCMAT  LDA     SBCTAB,X        ; SELECT SUBCOMMAND TABLE.
7CAE  8590                STA     TABADR
7CB0  BD217E              LDA     SBCTAB+1,X
7CB3  8591                STA     TABADR+1
7CB5  20BD7C              JSR     CMACOM          ; COMMON CODE.

                  ; *** OPTIONAL ENTRY FROM 'CMATCH' ***


7CB8              :CMA99
7CB8  08                  PHP                     ; SAVE CC.
7CB9  A4A1                LDY     TEMP            ; RESTORE INDEX IN 'INLN'.
7CBB  28                  PLP                     ; RESTORE CC FOR CALLER.
7CBC  60                  RTS


7CBD                      PROC
                  ;
                  ; CMACOM -- COMMON CODE FOR 'CMATCH' AND 'SBCMAT'
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'TABADR' = BASE ADDRESS OF MATCH TABLE.
                  ;       'INLN' POINTS TO SOURCE STATEMENT.
                  ;       Y = CURRENT INDEX IN 'INLN'
                  ;
                  ;       JSR CMACOM
                  ;       BNE NO MATCH IN TABLE (A = ERROR CODE)
                  ;
                  ;       X = 'OFFSET' BYTE
                  ;       Y = 'ATTRIBUTE' BYTE
                  ;       TEMP = INDEX TO START OF FIELD AFTER COMMAND NAME.
                  ;
                  ;
                  ; ALAS THE INDIRECT INDEXING OF THE 6502.
                  ;       MOVE '(INLN),Y' THROUGH '(INLN),Y + INBFSZ-1 TO
                  ;       A FIXED BUFFER, 'INLNBF', SO THAT 'X' CAN INDEX 'INLN'
                  ;       WHILE 'Y' INDEXES THE TABLE.
                  ;
                  ;       CONVERT LC -> UC IN 'INLNBF'.

7CBD  20139F      CMACOM  JSR     SLB             ; SKIP LOADING BLANKS
7CC0  84A1                STY     TEMP            ; SAVE INDEX IN 'INLN'
7CC2  20F79B              JSR     MVINLN          ; MOVE 'PART' OF 'INLN'

7CC5  A0FF                LDY     #$FF            ; SEARCH FROM THE BEGINNING OF '(TABADR)'
                                                  ; (PRE-DECREMENT).
7CC7  A2FF                LDX     #$FF            ; START AT TWO BEGINNING OF THE SOURCE.
                                                  ; (PRE-DECREMENT).

7CC9  C8          :CMA05  INY                     ; NEXT TABLE CHARACTER.
7CCA  E8                  INX                     ; NEXT SOURCE CHARACTER.
7CCB  B190                LDA     (TBLBAS),Y      ; SEE IF END OF NAME IN TABLE.

7CCD  3022 ^7CF1  :CMA10  BMI     :CMA70          ; YES -- MATCH FOUND.

7CCF  DD3805              CMP     INLNBF,X        ; MATCH NEXT SOUPCE CHAR?
7CD2  F0F5 ^7CC9          BEQ     :CMA05          ; YES -- CONTINUE COMPARISON.

7CD4  C8          :CMA20  INY                     ; SCAN TO END OF NANE ENTRY.
7CD5  B190                LDA     (TBLBAS),Y
7CD7  10FB ^7CD4          BPL     :CMA20

7CD9  C8                  INY                     ; SCAN PAST 'ATTRIBUTE' BYTE.
7CDA  C8                  INY                     ; SCAN PAST 'OFFSET' BYTE.

7CDB  C0F2                CPY     #$FF-INBFSZ-3   ; WILL INDEX WRAP?
7CDD  9008 ^7CE7          BCC     :CMA30          ; NO.
7CDF  98                  TYA                     ; YES -- ADJUST BASE POINTER.
7CE0  A210                LDX     #TBLBAS-DTAB
7CE2  20089D              JSR     DADDP
7CE5  A000                LDY     #0              ; ... AND RESET INDEX.

7CE7  A200        :CMA30  LDX     #0              ; RESTORE SOURCE INDEX.
7CE9  B190                LDA     (TBLBAS),Y      ; CHECK FOR END OF TABLE.
7CEB  D0E0 ^7CCD          BNE     :CMA10          ; NO -- KEEP CHECKING.

7CED  A902                LDA     #IVCERR         ; TABLE END -- INVALID COMMAND.
7CEF  D00F ^7D00          BNE     :CMA90          ; (BRA).

7CF1  48          :CMA70  PHA                     ; VALUE OF 'ATTRIBUTE' BYTE.
7CF2  8A                  TXA                     ; OFFSET IN 'INLNBF'.
7CF3  18                  CLC
7CF4  65A1                ADC     TEMP            ; + INITIAL OFFSET IN 'INLN'.
7CF6  85A1                STA     TEMP            ; INDEX TO START OF FIELD AFTER NAME.
7CF8  C8                  INY
7CF9  B190                LDA     (TBLBAS),Y      ; 'OFFSET' BYTE.
7CFB  AA                  TAX
7CFC  68                  PLA                     ; VALUE OF 'ATTRIBUTE' BYTE.
7CFD  A8                  TAY
7CFE  A900                LDA     #0              ; SET CC FOR EXIT.
7D00  60          :CMA90  RTS

7D01                      PROC

                  ;
                  ; 'USRTAB' -- USFR EXTENDABLE COMMAND TABLE
                  ;
                  ; SAVE STRUCTURE AS 'CTAB'
                  ;
                  ; THE EQUIVALENT 'CDTAB' IS APPENDED TO 'USRTAB' SO THAT
                  ; THE OFFSETS ARE ACTUALLY FROM THE BEGINNING OF 'USRTAB'.
                  ;
                  ; THE TOTAL LENGTH CF 'USRTAB' MAY NOT EXCEED 'USRMAX'.
                  ;
                  ; COMMAND TABLE
                  ;
                  ; CONSISTS OF N ENTRIES, EACH OF THE FOLLOWING FORMAT:
                  ;
                  ;       DB "<COMMAND NAME> ".
                  ;           $80+ [IMMEDIATE]+[RUN]+[: REQUIRED].
                  ;           INDEX TO COMMAND DATA TABLE.
                  ;
                  ; THE TABLE IS ENDED BY "<NAME>" = 0.
                  ; ORDER OF ENTRIES IS ONLY RESTRICTED BY FIRST FOUND - FIRST MATCHED, NOT BEST FIT.
                  ;
      = 0080      SB      = $80                   ; SIGN BIT.
      = 0040      CTIMM   = $40                   ; IMMEDIATE COMMAND.
      = 0020      CTRUN   = $20                   ; RUN COMMAND.
      = 0010      CTCLN   = $10                   ; : REQUIRED.
      = 0060      CTBOTH  = CTIMM+CTRUN           ; IMMEDIATE OR RUN COMMAND.
      = 0060      CTNORM  = CTBOTH+CTCLN-CTCLN    ; IMMEDIATE OR RUN COMMAND, : REQUIRED.

      = 7D01      CTAB    = *                     ; INTERNAL COMMAND TABLE BASE ADDRESS.

7D01  44454C4159          DB   'DELAY',SB+CTNORM,:CDSPD-CDTAB ; DELAY.

7D08  4C495354C0          DB   'LIST',SB+CTIMM,:CDLST-CDTAB  ; LIST STORED PROGRAM.

7D0E  44454CC00A          DB   'DEL',SB+CTIMM,:CDDEL-CDTAB   ; DELETE RANGE OF LINES.

7D13  52554EC00E          DB   'RUN',SB+CTIMM,:CDRUN-CDTAB   ; RUN STORED PROGRAM.

      = 0000              IF   DOS
   -                      DB   'DOS',SB+CTIMM,:CDDOS-CDTAB   ; GO TO DOS UTILITY.
                          ENDIF

7D18  53415645C0          DB   'SAVE',SB+CTIMM,:CDSAV-CDTAB  ; SAVE STORED PROGRAM.

7D1E  4E4557C048          DB   'NEW',SB+CTIMM,:CDNEW-CDTAB   ; CLEAR PROGRAM & VARS.

7D23  4155544FC0          DB   'AUTO',SB+CTIMM,:CDAUT-CDTAB  ; AUTO-INPUT.

7D29  52454EC01A          DB   'REN',SB+CTIMM,:CDREN-CDTAB   ; RENUMBER PROGRAM.

7D2E  434F4E54C0          DB   'CONT',SB+CTIMM,:CDCON-CDTAB  ; CONTINUE.

7D34  5053C01C            DB   'PS',SB+CTIMM,:CDCOL-CDTAB    ; TURTLE PEN STATUS.

7D38  4553C01E            DB   'ES',SB+CTIMM,:CDENS-CDTAB    ; TURTLE ENVIRONMENT STATUS.

7D3C  434F4C4F52          DB   'COLORS',SB+CTIMM,:CDPAL-CDTAB ; PALETTE OF COLORS.

7D44  444952C022          DB   'DIR', SB+CTIMM,:CDDIR-CDTAB  ; DISK DIRECTORY.

7D49  48454C50C0          DB   'HELP',SB+CTIMM,:CDCOM-CDTAB  ; COMMAND LIST.


7D4F  44554D50E0          DB   'DUMP',SB+CTBOTH,:CDDMP-CDTAB ; DUMP.

7D55  4C4F4144E0          DB   'LOAD',SB+CTBOTH,:CDLOD-CDTAB ; LOAD.

7D5B  4D45524745          DB   'MERGE',SB+CTIMM,:CDMRG-CDTAB ; MERGE.

7D62  415050454E          DB   'APPEND',SB+CTIMM,:CDAPP-CDTAB ; APPEND.

7D6A  5452414345          DB   'TRACE',SB+CTBOTH,:CDTRC-CDTAB ; TRACE.

7D71  564E4557E0          DB   'VNEW',SB+CTBOTH,:CDNWV-CDTAB  ; VNEW.

7D77  5456E04C            DB   'TV',SB+CTBOTH,:CDTV-CDTAB     ; TV.

7D7B  43414C4CE0          DB   'CALL',SB+CTNORM,:CDCAL-CDTAB  ; CALL.

7D81  54415045E0          DB   'TAPE',SB+CTNORM,:CDCSS-CDTAB  ; CASSETTE ON/OFF.

7D87  5453594E43          DB   'TSYNC',SB+CTNORM,:CDSNC-CDTAB ; CASSETTE SYNC.

7D8E  52454144E0          DB   'READ' ,SB+CTNORM,:CDIN-CDTAB  ; READ RECORD.

7D94  5752495445          DB   'WRITE',SB+CTNORM,:CDOUT-CDTAB ; WRITE RECORD.

7D9B  434C4F5345          DB   'CLOSE',SB+CTNORM,:CDDON-CDTAB ; CLOSE FILE.

7DA2  54E000              DB   'T',SB+CTNORM,:CDT-CDTAB      ; TYPE.

7DA5  4C45545445          DB   'LETTERS',SB+CTRUN,:CDLTR-CDTAB ; LETTERS

7DAE  414BE064            DB   'AK',SB+CTNORM,:CDAK-CDTAB    ; ACCEPT KEYSTROKE.

7DB2  4158E062            DB   'AX',SB+CTNORM,:CDAX-CDTAB    ; ACCEPT LITERAL.

7DB6  41E02E              DB   'A',SB+CTNORM,:CDA-CDTAB      ; ACCEPT.

7DB9  43E030              DB   'C',SB+CTNORM,:CDC-CDTAB      ; COMPUTE.

7DBC  55E032              DB   'U',SB+CTNORM,:CDU-CDTAB      ; USE.

7DBF  45E034              DB   'E',SB+CTNORM,:CDE-CDTAB      ; END.

7DC2  4A4DE036            DB   'JM',SB+CTNORM,:CDJM-CDTAB    ; JUMP ON MATCH.

7DC6  4AE038              DB   'J',SB+CTNORM,:CDJ-CDTAB      ; JUMP.

7DC9  4752E03A            DB   'GR',SB+CTNORM,CDG-CDTAB      ; GRAPHICS.

7DCD  4D5358E03C          DB   'MSX',SB+CTNORM,:CDMSX-CDTAB

7DD2  4D53E03E            DB   'MS',SB+CTNORM,:CDMS-CDTAB    ; MATCH (PRODUCING)

7DD6  4D58E040            DB   'MX',SB+CTNORM,:CDMX-CDTAB

7DDA  4DE042              DB   'M',SB+CTNORM,:CDM-CDTAB      ; MATCH.

7DDD  534FE044            DB   'SO',SB+CTNORM,:CDS-CDTAB     ; SOUNDS.

7DE1  52E006              DB   'R',SB+CTNORM,:CDR-CDTAB      ; REMARK.

7DE4  5041E046            DB   'PA',SB+CTNORM,:CDW-CDTAB     ; PAUSE.

7DE8  59E002              DB   'Y',SB+CTNORM,:CDY-CDTAB      ; TYPE IF YES.

7DEB  4EE004              DB   'N',SB+CTNORM,:CDN-CDTAB      ; TYPE IF NO.

7DEE  504F53E054          DB   'POS',SB+CTNORM,:CDPOS-CDTAB  ; POSITION.

7DF3  53544F50A0          DB   'STOP',SB+CTRUN,:CDSTP-CDTAB  ; STOP.

7DF9  5345545045          DB   'SETPEN',SB+CTNORM,:CDSTC-CDTAB ; SET COLOR.

7E01  5345544C45          DB   'SETLET',SB+CTNORM,:CDSTL-CDTAB    ; SET LETTERS

7E09  5343524F4C          DB   'SCROLL',SB+CTBOTH,:CDSCR-CDTAB ; SCROLL SELECT.

7E11  5353415645          DB   'SSAVE',SB+CTNORM,:CDSSA-CDTAB  ; SCREEN SAVE.

7E18  534C4F4144          DB   'SLOAD',SB+CTNORM,:CDSLO-CDTAB  ; SCREEN LOAD.

7E1F  00                  DB   0                               ; END OF TABLE.

                  ;
                  ; SUBCOMMAND TABLES
                  ;
                  ; THERE CAN BE UP TO 128 SUBCOMMAND TABLES.
                  ; THE STRUCTURE OF EACH IS IDENTICAL TO THE COMMAND TABLE EXCEPT:
                  ;       THE 'OFFSET' BYTE CAN REPRESENT A 'VALUE', WITH THE
                  ;       CALLER DECIDING WHICH.
                  ;
                  ; THE CALLER SELECTS WHICH SUBCOMMAND TABLE BY SETTING ON INDEX
                  ; TO THE TABLE ADDRESS FROM 'SBCTAB'.
                  ;


      = 7E20      SBCTAB  = *                     ; BASE ADDRESS OF SUBCOMMAND TABLE ADDRESSES
      = 0000      OPTABX  = *-SBCTAB              ; NUMERICAL/RELATONAL OPERATIONS (BINARY).
7E20  347E                DW OPTAB
      = 0002      UNTABX  = *-SBCTAB              ; UNARY OPERATORS.
7E22  677E                DW UNTAB
      = 0004      GTABX   = *-SBCTAB              ; GRAPHICS SUBCOMMAND TABLE.
7E24  767E                DW GTAB
      = 0006      PCTABX  = *-SBCTAB              ; PEN COLOR TABLE.
7E26  707F                DW PCTAB
      = 0008      UPDWNX  = *-SBCTAB              ; UP/DOWN TABLE.
7E28  E17F                DW UPDTAB
      = 000A      ONOFFX  = *-SBCTAB              ; ON/OFF COMMAND TABLE.
7E2A  EC7F                DW ONFTAB
      = 000C      LTTABX  = *-SBCTAB              ; LETTERS COMMAND TABLE.
7E2C  F67F                DW LTRTAB
      = 000E      EDTABX  = *-SBCTAB              ; EDGE COMMAND TABLE.
7E2E  0D80                DW EDGTAB
      = 0010      SCTABX  = *-SBCTAB              ; SCROLL OPTION TABLE.
7E30  2880                DW SCRLTB
      = 0012      WLTABX  = *-SBCTAB              ; WALL OPTION TABLE.
7E32  3780                DW WALLTB

      = 7E34      OPTAB = *                       ; NUMERIC/RELATIONAL OPERATORS (BINARY).

7E34  2B8000              DB   '+',SB,:CDPLS-SBDTAB

7E37  2D8002              DB   '-',SB,:CDSUB-SBDTAB

7E3A  2F8004              DB   '/',SB,:CDDIV-SBDTAB

7E3D  2A8006              DB   '*',SB,:CDMUL-SBDTAB

7E40  3C3E8008            DB   '<>',SB,:CDNE-SBDTAB

7E44  3E3D800A            DB   '>=',SB,:CDGE-SBDTAB

7E48  3C3D800C            DB   '<=',SB,:CDLE-SBDTAB

7E4C  3D800E              DB   '=',SB,:CDEQ-SBDTAB

7E4F  3E8012              DB   '>',SB,:CDGT-SBDTAB

7E52  3C8010              DB   '<',SB,:CDLT-SBDTAB

7E55  5C8014              DB   BSLASH,SB,:CDMOD-SBDTAB

7E58  414E448016          DB   'AND',SB,:CDAND-SBDTAB

7E5D  4F528018            DB   'OR',SB,:CDOR-SBDTAB

7E61  584F52801A          DB   'XOR',SB,:CDXOR-SBDTAB

      = 0000              IF   LOGGRP

   -                      DB   'LAND',SB,:CDLAN-SBDTAB

   -                      DB   'LOR',SB,:CDLOR-SBDTAB

                          ENDIF

7E66  00                  DB   0                  ; END OF TABLE.

      = 7E67      UNTAB   = *                     ; UNARY OPERATORS

7E67  2D801C              DB   '-',SB,:CDUMI-SBDTAB

7E6A  4E4F54801E          DB   'NOT',SB,:CDNOT-SBDTAB

7E6F  4C4E4F5480          DB   'LNOT',SB,:CDLNO-SBDTAB

7E75  00                  DB   0                  ; END OF TABLE.

      = 7E76      GTAB = *                        ; GRAPHIC SUB-COMMAND TABLE.

7E76  4452415754          DB   'DRAWTO',SB,:CDDRT-SBDTAB

7E7E  4452415780          DB   'DRAW',SB,:CDDRW-SBDTAB

7E84  5455524E54          DB   'TURNTO',SB,:CDTNT-SBDTAB

7E8C  5455524E80          DB   'TURN',SB,:CDTRN-SBDTAB

7E92  474F544F80          DB   'GOTO',SB,:CDGOT-SBDTAB

7E98  46494C4C54          DB   'FILLTO',SB,:CDFIT-SBDTAB

7EA0  46494C4C80          DB   'FILL',SB,:CDFIL-SBDTAB

7EA6  474F802C            DB   'GO',SB,:CDGO-SBDTAB

7EAA  4348414E47          DB   'CHANGE',SB,:CDCHG-SBDTAB

7EB2  50454E8032          DB   'PEN',SB,:CDPEN-SBDTAB

7EB7  434C454152          DB   'CLEARPENS',SB,:CDCLP-SBDTAB

7EC2  434C454152          DB   'CLEAR',SB,:CDCLR-SBDTAB

7EC9  5155495480          DB   'QUIT',SB,:CDEXI-SBDTAB

7ECF  46554C4C80          DB   'FULL',SB,:CDFUL-SBDTAB

7ED5  53504C4954          DB   'SPLIT',SB,:CDSPT-SBDTAB

7EDC  57414C4C80          DB   'WALL',SB,:CDWAL-SBDTAB

7EE2  4544474580          DB   'EDGE',SB,:CDEDG-SBDTAB

7EE8  484F4D4580          DB   'HOME',SB,:CDHOM-SBDTAB

7EEE  4E4F525448          DB   'NORTH',SB,:CDNRT-SBDTAB

7EF5  545552544C          DB   'TURTLE',SB,:CDTRT-SBDTAB

7EFD  5348414445          DB   'SHADE',SB,:CDSHD-SBDTAB

7F04  4D4F444580          DB   'MODE',SB,:CDMDE-SBDTAB

7F0A  4241434B47          DB   'BACKGROUND',SB,:CDBCK-SBDTAB

7F16  5345544880          DB   'SETH',SB,:CDTNT-SBDTAB

7F1C  5345544247          DB   'SETBG',SB,:CDBCK-SBDTAB

7F23  434C45414E          DB   'CLEAN',SB,:CDCLR-SBDTAB

7F2A  46448024            DB   'FD',SB,:CDDRW-SBDTAB

7F2E  424B8050            DB   'BK',SB,:CDBK-SBDTAB

7F32  52548028            DB   'RT',SB,:CDTRN-SBDTAB

7F36  4C548052            DB   'LT',SB,:CDLTU-SBDTAB

7F3A  534554504F          DB   'SETPOS',SB,:CDDRT-SBDTAB

7F42  5245504541          DB   'REPEAT',SB,:CDRPT-SBDTAB

7F4A  524F424F54          DB   'ROBOT',SB,:CDRBT-SBDTAB

7F51  4559455380          DB   'EYES',SB,:CDEYS-SBDTAB

7F57  5250454E80          DB   'RPEN',SB,:CDRPN-SBDTAB

7F5D  484F524E80          DB   'HORN',SB,:CDHRN-SBDTAB

7F63  5044805A            DB   'PD',SB,:CDPD-SBDTAB

7F67  50558058            DB   'PU',SB,:CDPU-SBDTAB

7F6B  50458056            DB   'PE',SB,:CDPE-SBDTAB

7F6F  00                  DB   0                  ; END OF TABLE.

      = 7F70      PCTAB = *                       ; PEN COLOR TABLE.
7F70  5245448042          DB   'RED',SB,CRED

7F75  59454C4C4F          DB   'YELLOW',SB,CYELLO

7F7D  475245454E          DB   'GREEN',SB,$C6

7F84  424C554580          DB   'BLUE',SB,CBLUE

7F8A  424C41434B          DB   'BLACK',SB,CBLACK

7F91  5748495445          DB   'WHITE',SB,$0E

7F98  4F52414E47          DB   'ORANGE',SB,$F4

7FA0  505552504C          DB   'PURPLE',SB,$52

7FA8  4752415980          DB   'GRAY',SB,$04

7FAE  53494C5645          DB   'SILVER',SB,$06

7FB6  474F4C4480          DB   'GOLD',SB,$28

7FBC  50494E4B80          DB   'PINK',SB,$46

7FC2  4C4156454E          DB   'LAVENDER',SB,$64

7FCC  42524F574E          DB   'BROWN',SB,$E0

7FD3  4245494745          DB   'BEIGE',SB,$FE

7FDA  4552415345          DB   'ERASE',SB,0

      = 7FE1      UPDTAB = *                      ; UP/DOWN TABLE.

7FE1  55508080    PCTUP   DB   'UP',SB,PCUP

7FE5  444F574E80  PCTDN   DB   'DOWN',SB,PCDN

7FEB  00                  DB   0                  ; END OF TABLE.

      = 7FEC      ONFTAB = *                      ; ON/OFF COMMAND TABLE.

7FEC  4F4E8001            DB   'ON',SB,KON

7FF0  4F46468000          DB   'OFF',SB,KOFF

7FF5  00                  DB   0                  ; END OF TABLE.

      = 7FF6      LTRTAB  = *                     ; LETTERS COMMAND TABLE.

7FF6  534D414C4C          DB   'SMALL',SB,LSMLL

7FFD  4D45444955          DB   'MEDIUM',SB,LMED

8005  4C41524745          DB   'LARGE',SB,LLRG

800C  00                  DB   0                  ; END OF TABLE.

      = 800D      EDGTAB  = *                     ; EDGE COMMAND TABLE.

800D  5752415080          DB   'WRAP',SB,EWRAP

8013  48414C5480          DB   'HALT',SB,EHALT

8019  424F554E43          DB   'BOUNCE',SB,EBNC

8021  4652454580          DB   'FREE',SB,EFREE

8027  00                  DB   0                  ; END OF TABLE.

      = 8028      SCRLTB  = *                     ; SCROLL OPTION COMMAND.

8028  434F415253          DB   'COARSE',SB,0

8030  46494E4580          DB   'FINE',SB,$FF

8036  00                  DB   0

      = 8037      WALLTB  = *                     ; WALL OPTION

8037  4E4F4E4580          DB   'NONE',SB,0

803D  00                  DB   0                  ; END OF TABLE.

                  ;
                  ; COMMAND DATA TABLE
                  ;
                  ; CONSISTS OF N WORDS, THE INDICES TO THIS TABLE ARE
                  ; CONTAINED IN 'CTAB'. THE TOTAL NUMBER OF BYTES IN THE TABLE MAY NOT
                  ; EXCEED 128.
                  ;
                  ; NOTE:  THIS OFFSET IS USED TO 'TOKENIZE' THE COMMAND.
                  ;        THE 'MSB' FLAGS THAT THE COMMAND IS IN 'USRTAB',
                  ;        THE USER EXTENDABLE COMMAND TABLE.
                  ;        ($FE AND $FF ARE RESERVED.)
                  ;
                  ; 'CDTAB' IS SEGMENTED FOR ': CONTINUATION' IN RUN MODE.
                  ; ENTRIES BEFORE 'CLNCNT' ALLOW ': CONTINUATION'?
                  ; OTHER ENTRIES DO NOT.
                  ;

      = 803E      CDTAB = *         ; COMMAND DATA TABLE BASE ADDRESS.

                  ; ': CONTINUATION' IS VALID IN RUN MODE.

803E  E183        :CDT    DW   XTYPE
8040  6684        :CDY    DW   XTYPE2
8042  6E84        :CDN    DW   XTYPE3
8044  7484        :CDR    DW   XREM

                  ; ': CONTINUATION' IS NOT VALID IN RUN MODE.

      = 0008      CLNCNT  =    *-CDTAB

8046  A790        :CDLST  DW   XLIST
8048  6F91        :CDDEL  DW   XDELET
804A  A688        :CDDMP  DW   XDUMP
804C  F284        :CDRUN  DW   XRUN
      = 0000              IF   DOS
   -              :CDDOS  DW   XDOS
                          ENDIF
804E  FC8F        :CDLOD  DW   XLOAD
8050  2B90        :CDMRG  DW   XMERGE
8052  3890        :CDAPP  DW   XAPPND

8054  CB8F        :CDSAV  DW   XSAVE
8056  1391        :CDAUT  DW   XAUTO
8058  FF91        :CDREN  DW   XREN
805A  1F8A        :CDCOL  DW   XCOLRS
805C  A48A        :CDENS  DW   XENVIR
805E  098A        :CDPAL  DW   XPALET
8060  C38E        :CDDIR  DW   XDIR
8062  068F        :CDCOM  DW   XCOMM
8064  D387        :CDCAL  DW   XCALL
8066  BA8F        :CDTRC  DW   XTRACE
8068  868F        :CDCSS  DW   XCASS
806A  9C8F        :CDSNC  DW   XCSYNC
806C  4385        :CDA    DW   XACCPT
806E  4B8B        :CDC    DW   XCMPUT
8070  E987        :CDU    DW   XUSE
8072  C284        :CDE    DW   XEND
8074  7888        :CDJM   DW   XJMPM
8076  0F88        :CDJ    DW   XJMP
8078  178C        CDG     DW   XGRAPH
807A  2C87        :CDMSX  DW   XMATSX
807C  3287        :CDMS   DW   XMWSP
807E  7086        :CDMX   DW   XMATX
8080  6C86        :CDM    DW   XMATCH
8082  CA8C        :CDS    DW   XSOUND
8084  548F        :CDW    DW   XWAIT
8086  B987        :CDNEW  DW   XNEW
8088  A087        :CDNWV  DW   XNEWV
808A  218B        :CDTV   DW   XTV
808C  6A8D        :CDIN   DW   XIN
808E  C48D        :CDOUT  DW   XOUT
8090  F78D        :CDDON  DW   XDONE
8092  7A84        :CDPOS  DW   XPOS
8094  31A4        :CDSTC  DW   XSETP
8096  26A4        :CDSTL  DW   XSETL
8098  4A90        :CDLTR  DW   XLETTR
809A  778F        :CDSPD  DW   XSPEED
809C  3485        :CDCON  DW   XCONT
809E  ED84        :CDSTP  DW   XSTOP
80A0  5786        :CDAX   DW   XACCX
80A2  6486        :CDAK   DW   XACCK
80A4  7F90        :CDSCR  DW   XSCROLL
80A6  088E        :CDSSA  DW   XSSAV
80A8  5E8E        :CDSLO  DW   XSLOD


      = 006C      TABLEN  SET *-CDTAB
      = 006C      USROFF  EQU TABLEN              ; USER TOKENS START AT THIS NUMBER.
      = 0092      USRMAX  EQU TKNCNT-USROFF       ; USER TABLE OFFSET MAY NOT EXCEED USRMAX.

                  ; SUBCOMMAND DATA TABLE
                  ;
                  ; CORRESPONDING DATA TABLE
                  ;

      = 80AA      SBDTAB  = *
80AA  329C        :CDPLS  DW   DADDI
80AC  429C        :CDSUB  DW   DSUBI
80AE  879C        :CDDIV  DW   DDIVI
80B0  549C        :CDMUL  DW   DMULI
80B2  259D        :CDNE   DW   DNETI
80B4  3C9D        :CDGE   DW   DGETI
80B6  439D        :CDLE   DW   DLETI
80B8  1E9D        :CDEQ   DW   DEQTI
80BA  359D        :CDLT   DW   DLTTI
80BC  2C9D        :CDGT   DW   DGTTI
80BE  E59C        :CDMOD  DW   DMODI
80C0  689D        :CDAND  DW   DANDI
80C2  779D        :CDOR   DW   DORI
80C4  869D        :CDXOR  DW   DXORI
      = 0000              IF   LOGGRP
   -              :CDLAN  DW   DLANDI
   -              :CDLOR  DW   DLORI
                          ENDIF


80C6  F19C        :CDUMI  DW   DNEGI
80C8  959D        :CDNOT  DW   DNOTI
80CA  579D        :CDLNO  DW   DLNOTI


80CC  B5A1        :CDDRT  DW   GDRWTO
80CE  0FA2        :CDDRW  DW   GDRW
80D0  E9A1        :CDTNT  DW   GTRNTO
80D2  57A2        :CDTRN  DW   GTRN
80D4  B9A1        :CDGOT  DW   GGOTO
80D6  13A2        :CDGO   DW   GGO
80D8  B1A1        :CDFIT  DW   GFILTO
80DA  0BA2        :CDFIL  DW   GFIL
80DC  75A2        :CDPEN  DW   GPEN
80DE  E2A2        :CDCHG  DW   GCHNGE
80E0  ADA3        :CDCLP  DW   GCLRPN
80E2  A0A3        :CDCLR  DW   GCLEAR
80E4  91A3        :CDEXI  DW   GEXIT
80E6  79A1        :CDFUL  DW   GFULL
80E8  98A1        :CDSPT  DW   GSPLIT
80EA  53A3        :CDWAL  DW   GWALL
80EC  DBA3        :CDEDG  DW   GEDGE
80EE  B7A3        :CDHOM  DW   GHOME
80F0  CDA3        :CDNRT  DW   GNORTH
80F2  FBA3        :CDTRT  DW   GTURTL
80F4  1AA3        :CDSHD  DW   GSHADE
80F6  3DA1        :CDMDE  DW   GMODE
80F8  C6A2        :CDBCK  DW   GBACK
80FA  FBA1        :CDBK   DW   GBK
80FC  4CA2        :CDLTU  DW   GLT
80FE  B98C        :CDRPT  DW   GREPT
8100  BDA2        :CDPE   DW   GPE
8102  ABA2        :CDPU   DW   GPU
8104  B4A2        :CDPD   DW   GPD


8106  5DB3        :CDRBT  DW   RONOFF
8108  89B3        :CDEYS  DW   REYES
810A  9AB3        :CDRPN  DW   RPEN
810C  B3B3        :CDHRN  DW   RHORN

      = 0064      TABLEN  SET    *-SBDTAB         ; THIS MUST NOT EXCEED 0100 HEX.

                          ASSERT TABLEN<$100

810E                      PROC
                  ;
                  ; COND -- CONDITIONAL EXECUTION PROCESSOR
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'INLN' POINTS TO STATEMENT TO BE PROCESSED
                  ;       Y = INDEX TO START OF CONDITION.
                  ;       'MATCHF' = 0 (FALSE) OR $FF (TRUE) , RESULT OF PRIOR 'M' COMMAND
                  ;
                  ;       JSR     COND
                  ;
                  ;       Y = INDEX TO ':' IN STATEMENT + 1.
                  ;       'EXECF' = 0 IF STATEMENT IS NOT TO BE EXECUTED.
                  ;
                  ; NOTE: GOES TO 'PSTOP' ON ERROR.
                  ;
                  ; NOTE: 'LOOK AHEAD' CODE FOR GRAPHICS SUBCOMMANDS BEGINNING
                  ;       WITH 'Y' OR 'N'
                  ;
810E  A9FF        COND    LDA     #$FF            ; PRESET EXECUTE FLAG.
8110  8D0605              STA     EXECF
8113  20139F              JSR     SLB             ; GET FIRST CHAR OF CONDITION FIELD.

                  ; VALID CHARACTERS ARE Y,N,(,:

8116  0920                ORA     #LC             ; FORCE LOWER CASE.
8118  C979                CMP     #'Y'+$20        ; CHECK FOR 'Y' OR 'N' FIRST.
811A  D005 ^8121          BNE     :CN010

811C  A5FE                LDA     MATCHF          ; 'Y' -- IF 'MATCHF' IS TRUE, RESULT IS TRUE.
811E  4C3581              JMP     :CN015

8121  C96E        :CN010  CMP     #'N'+$20
8123  D017 ^813C          BNE     :CN030          ; NOT 'Y' OR 'N'.

                  ; SPECIAL CASE '(IMPLIED GR:) NORTH'

8125  C8                  INY
8126  B180                LDA     (INLN),Y
8128  88                  DEY                     ; POINT INDEX TO 'N'.
8129  0920                ORA     #LC             ; FORCE LOWER CASE.
812B  C96F                CMP     #'O'+$20        ; LOWER CASE 'O'?
812D  F02D ^815C          BEQ     :CN070          ; YES -- TRY 'NORTH'.

812F  A5FE                LDA     MATCHF          ; 'N' -- IF 'MATCHF' IS FALSE, RESULT IS TRUE.
8131  F005 ^8138          BEQ     :CN017

8133  A900                LDA     #0

8135  8D0605      :CN015  STA     EXECF

8138  C8          :CN017  INY
8139  20139F              JSR     SLB             ; GET NEXT NON-BLANK CHARACTER.

813C  B180        :CN030  LDA     (INLN),Y
813E  C928                CMP     #'('             ; SEE IF ARITHMETIC EXPRESSION.
8140  D015 ^8157          BNE     :CN050          ; NO -- ALL DONE.

8142  200FA0              JSR     EXPP            ; EVALUATE EXPRESSION IN PARENS.

8145  A594                LDA     EXPSTK+1        ; SEE IF RESULT > ZERO.
8147  3006 ^814F          BMI     :CN032          ; NO -- NEGATIVE.

8149  D009 ^8154          BNE     :CN040          ; YES -- POSITIVE & NON-ZERO.

814B  A593                LDA     EXPSTK          ; NOT SURE -- TEST LSB.
814D  D005 ^8154          BNE     :CN040          ; POSITIVE & NON-ZERO.

814F  A900        :CN032  LDA     #0              ; NO -- CONDITION FALSE.
8151  8D0605              STA     EXECF

8154  20139F      :CN040  JSR     SLB             ; GET NEXT NON-BLANK CHARACTER.

8157  C93A        :CN050  CMP     #':'             ; COLON?
8159  D002 ^815D          BNE     :CN080          ; NO.

815B  C8                  INY                     ; SKIP OVER ':'.
815C  60          :CN070  RTS

                  ; ':-REQUIRED' ATTRIBUTE ONLY AVAILABLE DURING SYNTAX CHECK.

815D  A592        :CN080  LDA     EXEC            ; CHECK ': REQUIRED'?
815F  D0FB ^815C          BNE     :CN070          ; NO.
8161  A910                LDA     #CTCLN          ; ':' REQUIRED FOR THIS COMMAND?
8163  2C1005              BIT     CTABAT
8166  F0F4 ^815C          BEQ     :CN070          ; NO.

8168  88                  DEY
8169  A902                LDA     #CNDERR         ; YES -- ERROR.
816B  4C3A7A              JMP     PSTOP


816E                      PROC
                  ;
                  ; ATOM -- FIND, IDENTIFY & EVALUATE THE NEXT ATOM IN THE STATEMENT LINE.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'INLN' POINTS TO THE STATEMENT LINE.
                  ;       Y = INDEX TO END OF PRIOR ATOM + 1.
                  ;
                  ;       JSR     ATOM
                  ;       BNE     SYNTAX ERROR
                  ;
                  ;       A = ATOM IDENTIFIER CODE
                  ;       Y = INDEX TO END OF ATOM 1 (OR BEGINNING OF ATOM FOR TEXT TYPE).
                  ;       'NUMBER' = VALUE OF NUMERIC CONSTANT OR NUMERIC VARIABLE IF 'EXEC'.
                  ;       'POINT' = ADDRESS OF NUMERIC VARIABLE OR OPERATOR ROUTINE IF 'EXEC'.
                  ;       'NP' POINTS TO STRING VARIABLE NAME.
                  ;       'DP' POINTS TO STRING VARIABLE VALUE (IF DEFINED).
                  ;
816E  20139F      ATOM    JSR     SLB             ; SKIP LEADING BLANKS, IF PRESENT.

                  ; *** INTERNAL RE-ENTRY POINT ***

8171  20F99E      ATOM2   JSR     CHKTRM          ; NULL ATOM (STATEMENT TERMINATOR)?
8174  F038 ^81AE          BEQ     :AT100          ; YES.

8176  C923                CMP     #'#'            ; NUMERIC VARIABLE?
8178  F039 ^81B3          BEQ     :AT200          ; YES.

817A  C940                CMP     #'@'            ; POINTER?
817C  D003 ^8181          BNE     :AT002          ; NO.

817E  4C1382              JMP     :AT250          ; YES.

8181  C924        :AT002  CMP     #'$'            ; STRING VARIABLE?
8183  D003 ^8188          BNE     :AT003          ; NO.

8185  4C5182              JMP     :AT300          ; YES.

8188  C925        :AT003  CMP     #'%'            ; JOYSTICK/PADDLE/LIGHTPEN?
818A  D003 ^818F          BNE     :AT005          ; NO.

818C  4CC782              JMP     :AT700          ; YES.
818F  20839E      :AT005  JSR     CNUMBR          ; NUMERIC LITERAL?
8192  B003 ^8197          BCS     :AT010          ; NO

8194  4C9F82              JMP     :AT400          ; YES.

8197  A200        :AT010  LDX     #OPTABX         ; SPECIAL OPERATOR?
8199  20AB7C              JSR     SBCMAT
819C  D003 ^81A1          BNE     :AT020          ; NO.

819E  4CAC82              JMP     :AT600          ; YES.
81A1  B180        :AT020  LDA     (INLN),Y        ; RESTORE CHAR.
81A3  20919E              JSR     CLETTR          ; CONTEXT DEPENDENT TEXT?

81A6  B003 ^81AB          BCS     :AT099          ; NO.

81A8  4CA882              JMP     :AT500          ; YES.

81AB  A902        :AT099  LDA     #ATMERR         ; NONE OF THE ABOVE -- ERROR.
81AD  60                  RTS                     ; RETURN WITH CC SET.

                  ; NULL ATOM -- <EOL>

81AE  A901        :AT100  LDA     #NULL
81B0  4CA983              JMP     ATMRET

                  ; NUMERIC VARIABLE -- #<ANY NUMBER OF ALPHANUM>.

81B3  C8          :AT200  INY
81B4  B180                LDA     (INLN),Y        ; CHECK CHARACTER AFTER '#'.
81B6  20B69E              JSR     CKEOA
81B9  F0F0 ^81AB          BEQ     :AT099

81BB  A580                LDA     INLN            ; SET NAME POINTER TO NAME.
81BD  85BE                STA     NP
81BF  A581                LDA     INLN+1
81C1  85BF                STA     NP+1
81C3  84C0                STY     NP+2
81C5  20CB9E              JSR     SCEOA           ; SCAN TO END OF ATOM.

                  ; SKIP NUMBERIC VARIABLE LOCKUP IF NOT (EXEC).

81C8  A592                LDA     EXEC
81CA  F043 ^820F          BEQ     :AT220

81CC  84C1                STY     NP+3            ; SAVE LINE INDEX

                  ; ENTRY TO 'FIND' A "JUST - DEFINED" VARIABLE.

81CE  20AD9E      :AT205  JSR     SETSVL          ; SET LIST POINTER TO VARIABLES.
81D1  A940                LDA     #ATRNUM         ; 'NUMERIC' ATTRIBUTE.
81D3  8D6605              STA     ATRTYP
81D6  20CE98              JSR     SFIND           ; FIND VARIABLF IF DEFINED.
81D9  F01B ^81F6          BEQ     :AT210          ; DEFINED.

81DB  A900                LDA     #0              ; DATA = 00.
81DD  85B8                STA     NUMBER
81DF  85B9                STA     NUMBER+1
81E1  85C4                STA     DP+2
                  ; *S*   LDA     # HIGH NUMBER
81E3  85C3                STA     DP+1
81E5  A9B8                LDA     # LOW NUMBER
81E7  85C2                STA     DP
81E9  A902                LDA     #2
81EB  85C5                STA     DP+3
81ED  200599              JSR     SINSRT          ; INSEPT NUMERIC (VALUE = 0).

81F0  D0B9 ^81AB          BNE     :AT099          ; ERROR -- NO ROOM.

81F2  A4C1                LDY     NP+3            ; SEARCH AGAIN -- FIND IT.
81F4  D0D8 ^81CE          BNE     :AT205          ; (BRA).

81F6  A236        :AT210  LDX     #POINT-DTAB     ; ADDRESS OF VALUE ...
81F8  A042                LDY     #DP-DTAB
81FA  20459A              JSR     DMOVI
81FD  A5C4                LDA     DP+2
81FF  20049D              JSR     DADDS           ; ... IN 'POINT'.

8202  A000                LDY     #0              ; VALUE IN 'NUMBER'.
8204  B1B6                LDA     (POINT),Y
8206  85B8                STA     NUMBER
8208  C8                  INY
8209  B1B6                LDA     (POINT),Y
820B  85B9                STA     NUMBER+1

820D  A4C1                LDY     NP+3            ; RESTORE LINE INDEX.

820F  A904        :AT220  LDA     #NVAR
8211  D072 ^8285          BNE     :AT340          ; (BRA) TO 'ATMRET'.


                  ; POINTER (INDIRECT REFERENCE) -- @[B]<NUMERIC QUANTITY>

8213  C8          :AT250  INY                     ; EXAMINE CHARACTER AFTER '@'.
8214  B180                LDA     (INLN),Y
8216  0920                ORA     #LC             ; FORCE LOWER CASE.
8218  C962                CMP     #'B'+$20        ; POINTER TO BYTE?
821A  08                  PHP                     ; SAVE ANSWER.
821B  D001 ^821E          BNE     :AT255          ; NO -- POINTER TO WORD.

821D  C8                  INY                     ; YES -- SKIP OVER 'B'.

821E  B180        :AT255  LDA     (INLN),Y        ; GET CHARACTER FOR RECURSIVE CALL.

8220  207181              JSR     ATOM2           ; SEE WHAT FOLLOWS *** RECURSIVE CALL ***.
8223  D028 ^824D          BNE     :AT290          ; ERROR.

8225  2906                AND     #NVAR+NUM       ; MUST BE NUMERIC.
8227  F024 ^824D          BEQ     :AT290          ; ERROR.

8229  A5B8                LDA     NUMBER          ; RESULT IS ADDRESS OF DATA.
822B  85B6                STA     POINT
822D  A5B9                LDA     NUMBER+1
822F  85B7                STA     POINT+1

8231  84A1                STY     TEMP            ; SAVE LINE INDEX.
8233  A000                LDY     #0              ; GET DATA VALUE NOW.
8235  B1B6                LDA     (POINT),Y
8237  85B8                STA     NUMBER
8239  28                  PLP                     ; POINTER TO BYTE?
823A  D006 ^8242          BNE     :AT260          ; NO -- POINTER TO WORD.

823C  84B9                STY     NUMBER+1        ; YES MSB = 0.
823E  A980                LDA     #BPTR           ; TYPE = POINTER TO BYTE.
8240  D007 ^8249          BNE     :AT270          ; (BRA).

8242  C8          :AT260  INY
8243  B1B6                LDA     (POINT),Y       ; GET MSB OF DATA WORD.
8245  85B9                STA     NUMBER+1
8247  A904                LDA     #NVAR           ; TYPE = POINTER TO WORD.

8249  A4A1        :AT270  LDY     TEMP            ; RESTORE LINE INDEX.
824B  D038 ^8285          BNE     :AT340          ; (BRA) SKIP TO NORMAL RETURN.

824D  28          :AT290  PLP                     ; CLEANUP STACK BEFORE RETURN.
824E  4CAB81      :AT299  JMP     :AT099          ; ERROR RETURN (EXTENDED BRANCH)


                  ; STRING VARIABLE -- $<ANY NUMBER OF ALPHANUM>

8251  C8          :AT300  INY                     ; EXAMINE CHARACTER AFTER 'S'.
8252  B180                LDA     (INLN),Y
8254  C924                CMP     #'$'             ; STRING INDIRECTION?
8256  F030 ^8288          BEQ     :AT350          ; YES.

8258  20B69E              JSR     CKEOA           ; NO -- STRING NAME ERROR?
825B  F0F1 ^824E          BEQ     :AT299          ; YES.

825D  A580                LDA     INLN            ; NO -- SET NAME POINTER TO NAME
825F  85BE                STA     NP
8261  A581                LDA     INLN+1
8263  85BF                STA     NP+1
8265  84C0                STY     NP+2

8267  20CB9E              JSR     SCEOA           ; SCAN TO END OF ATOM.
826A  84C1                STY     NP+3            ; SAVE END INDEX.

826C  98          :AT320  TYA                     ; SAVE LINE INDEX.
826D  48                  PHA
826E  20AD9E              JSR     SETSVL          ; SET LIST POINTER TO STRING VARIABLES.
8271  A980                LDA     #ATRSTR         ; 'STRING' ATTRIBUTE.
8273  8D6605              STA     ATRTYP
8276  20CE98              JSR     SFIND           ; FIND VARIABLE IF DEFINED.
8279  D006 ^8281          BNE     :AT330          ; UNDEFINED.

827B  68                  PLA                     ; RESTORE LINE INDEX.
827C  A8                  TAY
827D  A908                LDA     #SVAR           ; DEFINED STRING VARIABLE.
827F  D004 ^8285          BNE     :AT340          ; (BRA) TO 'ATMRET'.

8281  68          :AT330  PLA                     ; RESTORE LINE INDEX.
8282  A8                  TAY
8283  A910                LDA     #USVAR          ; UNDEFINED STRING VARIABLE.

8285  4CA983      :AT340  JMP     ATMRET          ; *** SKIP BRANCH POINT ***

8288  205182      :AT350  JSR     :AT300          ; INDIRECTION -- GET NAME *** RECURSIVE CALL ***.
828B  D011 ^829E          BNE     :AT360          ; ERROR.

828D  C910                CMP     #USVAR          ; UNDEFINED STRING?
828F  F0F4 ^8285          BEQ     :AT340          ; YES -- ALL DONE.

8291  84A1                STY     TEMP            ; DEFINED -- USE DATA AS NAME FOR TARGET
8293  A23E                LDX     #NP-DTAB
8295  A042                LDY     #DP-DTAB
8297  203B9A              JSR     PMOVE
829A  A4A1                LDY     TEMP
829C  D0CE ^826C          BNE     :AT320          ; (BRA) NOW GET STRING.

829E  60          :AT360  RTS


                  ; NUMERIC LITERAL -- <DIGIT><ANY NUMBER OF DIGITS>

829F  A200        :AT400  LDX     #INLN-DTAB      ; POINT TO POINTER.
82A1  20BB9D              JSR     ASCDEC          ; CONVERT TO BINARY, RESULT TO 'NUMBER'.

82A4  A902                LDA     #NUM
82A6  D0DD ^8285          BNE     :AT340          ; (BRA) TO 'ATMRET'.

                  ; TEXT -- <LETTER><ANY NUMBER OF CHARACTERS>

82A8  A920        :AT500  LDA     #TEXT
82AA  D0D9 ^8285          BNE     :AT340          ; (BRA) TO 'ATMRET'

                  ; OPERATOR -- <OPERATOR>


82AC  BDAA80      :AT600  LDA     SBDTAB,X        ; GET OPERATE ROUTINE ADDRESS.
82AF  85B6                STA     POINT
82B1  BDAB80              LDA     SBDTAB+1,X
82B4  85B7                STA     POINT+1
82B6  A940                LDA     #OPR
82B8  D0CB ^8285          BNE     :AT340          ; (BRA) TO 'ATMRET'.

                  ; EVALUATE EXPRESSION -- %(<NEXP>)

82BA  200FA0      :AT620  JSR     EXPP            ; EVALUATE NEXP IN PARENS.
82BD  A593                LDA     EXPSTK          ; PASS BACK RESULT.
82BF  A694                LDX     EXPSTK+1
82C1  4C6283              JMP     :AT781

                  ; CONTROLLERS -- %<P!J!T><NUMBER> OR %<X!Y!Z!A!H!V!L!M!F> OR %<S!SR!ST>


82C4  4CAB81      :AT720  JMP     :AT099          ; ERROR.

82C7  C8          :AT700  INY                     ; SKIP OVER '%'.
82C8  B180                LDA     (INLN),Y        ; GET NEXT CHARACTER.
82CA  C928                CMP     #'('            ; EVAL?
82CC  F0EC ^82BA          BEQ     :AT620          ; YES.

82CE  0920                ORA     #LC             ; FORCE LOWER CASE.
82D0  C970                CMP     #'P'+$20        ; PADDLE CONTROLLER?
82D2  F035 ^8309          BEQ     :AT730          ; YES.

82D4  C96E                CMP     #'N'+$20        ; PEN NUMBER?
82D6  D003 ^82DB          BNE     :AT703          ; NO.
82D8  4CDA83              JMP     :AT960          ; YES.

82DB  C96B        :AT703  CMP     #'K'+$20        ; KEY PRESS READ?
82DD  F03B ^831A          BEQ     :AT735          ; YES.

82DF  C966                CMP     #'F'+$20        ; FREE MEMORY?
82E1  F045 ^8328          BEQ     :AT740          ; YES.

82E3  C96A                CMP     #'J'+$20        ; JOYSTICK?
82E5  F05A ^8341          BEQ     :AT760          ; YES.

82E7  C974                CMP     #'T'+$20        ; TRIGGER?
82E9  F066 ^8351          BEQ     :AT770          ; YES.

82EB  C973                CMP     #'S'+$20        ; TURTLE SENSORS?
82ED  D003 ^82F2          BNE     :AT705          ; NO.
82EF  4CAE83              JMP     :AT950          ; YES.

82F2  C978        :AT705  CMP     #'X'+$20        ; GRAPHICS X?
82F4  F074 ^836A          BEQ     :AT782          ; YES.

82F6  C979                CMP     #'Y'+$20        ; GRAPHICS Y?
82F8  F074 ^836E          BEQ     :AT784          ; YES.

82FA  C97A                CMP     #'Z'+$20        ; GRAPHICS PIXEL VALUE.
82FC  F07B ^8379          BEQ     :AT788          ; YES.

82FE  C961                CMP     #'A'+$20        ; GRAPHICS THETA ANGLE?
8300  F070 ^8372          BEQ     :AT786          ; YES.

      = 0000              IF      LITPEN
   -                      CMP     #'H'+$20        ; LIGHTPEN HORIZONTAL?
   -                      BEQ     :AT790          ; YES.

   -                      CMP     #'V'+$20        ; LIGHTPEN VERTICAL?
   -                      BEQ     :AT795          ; YES.

   -                      CMP     #'L'+$20        ; LIGHTPEN TRIGGER?
   -                      BEQ     :AT796          ; YES.
                          ENDIF

8302  C96D                CMP     #'M'+$20        ; MATCH RESULT?
8304  D0BE ^82C4          BNE     :AT720          ; NO.

8306  4C8083              JMP     :AT798          ; YES.

                  ; READ PADDLE CONTROLLER

8309  208583      :AT730  JSR     :AT800          ; GET VALUE THAT FOLLOWS 'R'.
830C  D036 ^8344          BNE     :AT761          ; ERROR.

830E  2907                AND     #$07            ; PADDLE # MODULO 8.
8310  AA                  TAX
8311  38                  SEC                     ; (CLEAR BORROW).
8312  A9E4                LDA     #228            ; RESULT = 228 - VALUE READ.
8314  FD7002              SBC     PADDL0,X
8317  4C6083              JMP     :AT780

831A  C8          :AT735  INY                     ; SKIP OVER 'K'.
831B  ADFC02              LDA     CH              ; KEYCODE READY?
831E  38                  SEC
831F  E9FF                SBC     #$FF
8321  F002 ^8325          BEQ     :AT737          ; NO.

8323  A901                LDA     #1              ; YES.

8325  4C6083      :AT737  JMP     :AT780

                  ; CALCULATE FREE MEMORY

8328  C8          :AT740  INY                     ; SKIP OVER 'F'.
8329  38                  SEC
832A  A5B2                LDA     S2L             ; 'NUMBER' = 'S2L' - 'S1H' + 1.
832C  E5B0                SBC     S1H
832E  85B8                STA     NUMBER
8330  A5B3                LDA     S2L+1
8332  E5B1                SBC     S1H+1
8334  85B9                STA     NUMBER+1
8336  E6B8                INC     NUMBER
8338  D002 ^833C          BNE     :AT745
833A  E6B9                INC     NUMBER+1
833C  A902        :AT745  LDA     #NUM            ; TYPE = NUMBER.
833E  4CA983              JMP     ATMRET

                  ; READ JOYSTICK

8341  208583      :AT760  JSR     :AT800          ; GET VALUE THAT FOLLOWS 'J'.
8344  D04D ^8393  :AT761  BNE     :AT890          ; ERROR *** SKIP BRANCH POINT ***

8346  2903                AND     #$03            ; JOYSTICK # MODULO 4.
8348  AA                  TAX
8349  BD7802              LDA     STICK0,X        ; GET JOYSTICK DATA FROM DATA BASE.
834C  490F                EOR     #$0F            ; INVERT DATA READ.
834E  4C6083              JMP     :AT780

                  ; READ TRIGGER

8351  208583      :AT770  JSR     :AT800          ; GET VALUE THAT FOLLOWS 'T'.
8354  D03D ^8393          BNE     :AT890          ; ERROR.

8356  290F                AND     #$0F            ; TRIGGER # MODULO 16.
8358  AA                  TAX
8359  BD7C02              LDA     PTRIG0,X        ; RESULT = SINGLE BIT.
835C  49FF                EOR     #$FF
835E  2901                AND     #$01

                  ; *** ENTRY FOR TURTLE SENSORS ***.

8360  A200        :AT780  LDX     #0              ; M.S.B. = 0.

8362  85B8        :AT781  STA     NUMBER          ; STORE RESULT.
8364  86B9                STX     NUMBER+1
8366  A902                LDA     #NUM            ; NUMERIC RESULT.
8368  D03F ^83A9          BNE     ATMRET          ; (BRA).

                  ; GRAPHICS PARAMETERS

836A  A26C        :AT782  LDX     #GX-DTAB        ; GRAPHICS X COORDINATE.
836C  B029 ^8397          BCS     :AT900          ; (BRA).

836E  A26F        :AT784  LDX     #GY-DTAB        ; GRAPHICS Y COORDINATE.
8370  B025 ^8397          BCS     :AT900          ; (BRA).

8372  A5F2        :AT786  LDA     THETA           ; GRAPHICS THETA ANGLE.
8374  A6F3                LDX     THETA+1
8376  C8                  INY
8377  D0E9 ^8362          BNE     :AT781          ; (BRA).

8379  C8          :AT788  INY
837A  205EAC              JSR     GREAD           ; READ GRAPHICS DATA.
837D  4C6083              JMP     :AT780

      = 0000              IF      LITPEN
                  ; READ LIGHTPEN

   -              :AT790  LDA     LPENH           ; LIGHTPEN HORIZONTAL VALUE.
   -                      BCS     :AT797          ; (BRA).

   -              :AT795  LDA     LPENV           ; LIGHTPEN VERTICAL VALUE.
   -                      BCS     :AT797          ; (BRA).

   -              :AT796  LDA     STICK0          ; GET LIGHTPEN TRIGGER.
   -                      EOR     #$01            ; INVERT BIT OF INTEREST.
   -                      AND     #$01

   -              :AT797  LDX     EXEC            ; EXECUTE MODE?
   -                      BEQ     :AT79B          ; NO.

   -                      LDX     #$0A            ; BACKGROUND = LIGHT GPAY.
   -                      STX     COLOR0+4

   -              :AT79B  INY
   -                      BNE     :AT780          ; (BRA).
                          ENDIF


                  ; READ MATCH FLAG

8380  A5FE        :AT798  LDA     MATCHF          ; MATCH RESULT FLAG.
8382  C8                  INY
8383  D0DB ^8360          BNE     :AT780          ; (BRA).

                  ; SUBROUTINE TO PROCESS NUMBER FOLLOWING %P, %J & %T.

8385  C8          :AT800  INY                     ; SKIP OVER 'P' OR 'J' OR 'T'.
8386  206E81              JSR     ATOM            ; *** RECURSIVE CALL ***.

8389  D009 ^8394          BNE     :AT895          ; ERROR.

838B  2906                AND     #NVAR+NUM       ; NUMERIC RESULT?
838D  F005 ^8394          BEQ     :AT895          ; NO -- ERROR.

838F  A5B8                LDA     NUMBER          ; YES.
8391  C5B8                CMP     NUMBER          ; SET CC FOR NORMAL EXIT.

8393  60          :AT890  RTS                     ; RETURN WITH CC SET.

8394  A902        :AT895  LDA     #ATMERR         ; INVALID # AFTER LETTER.
8396  60                  RTS                     ; RETURN WITH CC SET.

                  ; SUBROUTINE TO ROUND & STORE THE GRAPHICS COORDINATES

8397  C8          :AT900  INY
8398  B582                LDA     DTAB+2,X        ; GET FRACTIONAL PORTION.
839A  2A                  ROL     A               ; MSB OF FRACTION TO CARRY BIT.
839B  B580                LDA     DTAB+0,X        ; ROUND LSB.
839D  6900                ADC     #0
839F  85B8                STA     NUMBER
83A1  B581                LDA     DTAB+1,X        ; CARRY TO MSB.
83A3  6900                ADC     #0
83A5  85B9                STA     NUMBER+1
83A7  A902                LDA     #NUM            ; NUMERIC RESULT.

83A9  85A1        ATMRET  STA     TEMP            ; SET CC FOR EXIT.
83AB  C5A1                CMP     TEMP
83AD  60                  RTS

                  ; TURTLE SENSORS
                  ;
                  ; %S  = ROBOT IF ON, ELSE VISIBLE TURTLE.
                  ; %SR = ROBOT.
                  ; %ST = VISIBLE TURTLE.

83AE  C8          :AT950  INY                     ; SKIP OVER 'S'.
83AF  B180                LDA     (INLN),Y        ; GET NEXT CHARACTER.
83B1  C8                  INY                     ; SKIP OVER NEXT CHARACTER.
83B2  0920                ORA     #LC             ; FORCE LOWER CASE.
83B4  C972                CMP     #'R'+$20        ; %SR?
83B6  F00A ^83C2          BEQ     :AT952          ; YES.
83B8  C974                CMP     #'T'+$20        ; %ST?
83BA  F011 ^83CD          BEQ     :AT954          ; YES.

83BC  88                  DEY                     ; %S.
83BD  ADC505              LDA     RBTON           ; ROBOT OR VISIBLE?
83C0  F00B ^83CD          BEQ     :AT954          ; VISIBLE.

83C2  ADC505      :AT952  LDA     RBTON           ; SENSORS = 0 IF ROBOT OFF.
83C5  F099 ^8360          BEQ     :AT780          ; OFF.
83C7  200DB4              JSR     RRDSNS          ; ROBOT.
83CA  4C6083              JMP     :AT780

83CD  A592        :AT954  LDA     EXEC            ; EXECUTE MODE?
83CF  F006 ^83D7          BEQ     :AT956          ; NO.

83D1  2098AC              JSR     VTSENS
83D4  AD5005              LDA     TRTSNS          ; VISIBLE.

83D7  4C6083      :AT956  JMP     :AT780

                  ; %N = TURTLE PEN NUMBER

83DA  C8          :AT960  INY                     ; SKIP OVER 'N'.
83DB  AD1305              LDA     PEN             ; GET PEN #.
83DE  4C6083              JMP     :AT780


83E1                      PROC
                  ;
                  ; XTYPE -- TYPE COMMAND PROCESSOR
                  ;
83E1  20A7A0      XTYPE   JSR     TEXP            ; PROCESS TEXT EXPRESSION.

83E4  A592                LDA     EXEC            ; EXECUTE MODE?
83E6  F07D ^8465          BEQ     :XT090          ; NO.

83E8  20BB96              JSR     TSTMOD          ; CHECK SCREEN MODE.
83EB  C908                CMP     #GRFS           ; FULL SCREEN GRAPHICS.
83ED  D003 ^83F2          BNE     :XT005          ; NO.

83EF  A983                LDA     #NRCERR         ; YES -- ERROR.
83F1  60                  RTS

83F2  A68F        :XT005  LDX     TELN+3          ; CHECK FOR NULL TEXT.
83F4  F00C ^8402          BEQ     :XT010          ; NULL.

83F6  BDFFBB              LDA     TEXBUF-1,X      ; NON-NULL -- CHECK FINAL CHARACTER.
83F9  C95C                CMP     #BSLASH         ; IS IT EOL SUPPRESS?
83FB  D005 ^8402          BNE     :XT010          ; NO.

83FD  C68F                DEC     TELN+3          ; YES -- SUPPRESS ALSO.
83FF  4C0984              JMP     :XT020

8402  A99B        :XT010  LDA     #EOL            ; INSERT EOL.
8404  9D00BC              STA     TEXBUF,X
8407  E68F                INC     TELN+3

                  ; TYPE WITH WORD SPLIT AVOIDANCE.

8409  84AC        :XT020  STY     XTEMP+1         ; SAVE STATEMENT INDEX.
840B  A48E                LDY     TELN+2          ; STARTING INDEX.
840D  C48F                CPY     TELN+3
840F  F050 ^8461          BEQ     :XT080          ; NULL OUTPUT -- ALL DONE.

8411  84AB        :XT022  STY     XTEMP           ; SAVE INDEX.
8413  A655                LDX     COLCRS          ; GET CURRENT CURSOR POSITION.
8415  AD1405              LDA     GRFLAG          ; DIFFERENT CURSOR IF SPLIT SCREEN.
8418  F003 ^841D          BEQ     :XT025

841A  AE9102              LDX     TXTCOL          ; SPLIT SCREEN -- USE OTHER CURSOR.

841D  86AD        :XT025  STX     XTEMP+2         ; SAVE STARTING COLUMN #.
841F  CA                  DEX                     ; PRE-CONDITION THE INDEX.

8420  B18C        :XT030  LDA     (TELN),Y        ; FIND LENGTH OF NEXT WORD.
8422  E8                  INX
8423  C8                  INY
8424  C48F                CPY     TELN+3
8426  F004 ^842C          BEQ     :XT035          ; END OF TEXT.

8428  C920                CMP     #' '            ; SPACE?
842A  D0F4 ^8420          BNE     :XT030          ; NO -- KEEP SCANNING.

842C  A4AB        :XT035  LDY     XTEMP           ; END OF WORD -- CHECK FOR WORD SPLIT.
842E  ECB605              CPX     RGCOL           ; DOES IT WRAP SCREEN?
8431  F00C ^843F          BEQ     :XT040          ; NO -- OUTPUT IT.
8433  900A ^843F          BCC     :XT040          ; NO -- OUTPUT IT.

8435  A5AD                LDA     XTEMP+2         ; YES -- IS THIS THE 1ST WORD OF LINE?
8437  CDB505              CMP     LFCOL
843A  F003 ^843F          BEQ     :XT040          ; YES -- FORGET ABOUT NEW LINE.

843C  20989F              JSR     NEWLIN          ; NO -- START A NEW LINE.

843F  B18C        :XT040  LDA     (TELN),Y        ; OUTPUT THE WORD JUST SCANNED.
8441  C920                CMP     #' '            ; SPACE?
8443  D007 ^844C          BNE     :XT050          ; NO.

8445  ECB605              CPX     RGCOL           ; YES -- IS IT THE LAST POSITION?
8448  D002 ^844C          BNE     :XT050          ; NO.

844A  A99B                LDA     #EOL            ; YES -- CHANGE TO EOL.

844C  208294      :XT050  JSR     CHOT            ; OUTPUT CHAR.
844F  2048AA              JSR     SPDDEL          ; DELAY IF SPECIFIED.

8452  C8                  INY
8453  C48F                CPY     TELN+3          ; END OF TEXT?
8455  F00A ^8461          BEQ     :XT080          ; YES.

8457  88                  DEY
8458  B18C                LDA     (TELN),Y        ; SPACE?
845A  C8                  INY
845B  C920                CMP     #' '             ; SPACE?
845D  D0E0 ^843F          BNE     :XT040          ; NO -- NOT END OF WORD.

845F  F0B0 ^8411          BEQ     :XT022          ; YES -- NOW DO NEXT WORD (BRA).

8461  A4AC        :XT080  LDY     XTEMP+1         ; RESTORE STATEMENT INDEX.
8463  A900                LDA     #0              ; SET CC FOR EXIT.

8465  60          :XT090  RTS                     ; RETURN WITH CC SET.

                  ; 'Y' COMMAND PROCESSOR

8466  F00F ^8477  XTYPE2  BEQ     :XT500          ; SYNTAX SCAN ONLY.

8468  A5FE                LDA     MATCHF          ; Y COMMAND (SAME AS 'TY').
846A  D00B ^8477          BNE     :XT500

846C  F006 ^8474          BEQ     :XT400

                  ; 'N' COMMAND PROCESSOR

846E  F007 ^8477  XTYPE3  BEQ     :XT500          ; SYNTAX SCAN ONLY.

8470  A5FE                LDA     MATCHF          ; N COMMAND (SAME AS 'TN').
8472  F003 ^8477          BEQ     :XT500          ; SKIP BRANCH TO 'XTYPE'.

8474              XREM                            ; REMARK COMMAND PROCESSOR TOO.

8474  4C1B9F      :XT400  JMP     SCNEOL          ; SCAN TO END OF LINE & RETURN WITH CC SET.

8477  4CE183      :XT500  JMP     XTYPE

847A                      PROC
                  ;
                  ; XPOS -- POSITION COMMAND PROCESSOR
                  ;
847A  20D49F      XPOS    JSR     EXP             ; COLUMN NUMBER.
847D  A592                LDA     EXEC            ; EXECUTE MODE?
847F  F019 ^849A          BEQ     :XP020          ; NO.

8481  20BB96              JSR     TSTMOD          ; CHECK SCREEN MODE.
8484  C908                CMP     #GRFS           ; FULL GRAPHICS?
8486  F034 ^84BC          BEQ     :XP080          ; YES -- IGNORE COMMAND.

8488  A594                LDA     EXPSTK+1        ; RANGE CHECK THE COLUMN #.
848A  D033 ^84BF          BNE     :XP900          ; TOO LARGE.

848C  A593                LDA     EXPSTK+0        ; PAST RIGHT MARGIN?
848E  CDB605              CMP     RGCOL
8491  F002 ^8495          BEQ     :XP010
8493  B02A ^84BF          BCS     :XP900          ; YES -- TOO LARGE.

8495  8555        :XP010  STA     COLCRS          ; O.K. -- STORE IT.
8497  8D9102              STA     TXTCOL          ; SPLIT SCREEN TOO.

849A  20079F      :XP020  JSR     SKPSEP          ; SKIP SEPARATOR.
849D  20D49F              JSR     EXP             ; ROW NUMBER.
84A0  A592                LDA     EXEC            ; EXECUTE MODE?
84A2  F01A ^84BE          BEQ     :XP090          ; NO.

84A4  AD3505              LDA     TRACE           ; TRACE EXECUTION?
84A7  0D4505              ORA     SGLSTP
84AA  D010 ^84BC          BNE     :XP080          ; YES -- IGNORE THIS COMMAND.

84AC  A594                LDA     EXPSTK+1        ; RANGE CHECK THE ROW 4.
84AE  D00F ^84BF          BNE     :XP900          ; TOO LARGE.

84B0  A593                LDA     EXPSTK+0
84B2  CDBF02              CMP     BOTSCR
84B5  B008 ^84BF          BCS     :XP900          ; TOO LARGE.

84B7  8554                STA     ROWCRS          ; O.K. -- STORE IT.
84B9  8D9002              STA     TXTROW          ; SPLIT SCREEN TOO.

84BC  A900        :XP080  LDA     #0              ; SET CC FOR NORMAL EXIT.

84BE  60          :XP090  RTS                     ; RETURN WITH CC SET.

84BF  A902        :XP900  LDA     #IMPERR         ; COLUMN/ROW OUT OF RANGE.
84C1  60                  RTS                     ; RETURN WITH CC SET.

84C2                      PROC
                  ;
                  ; XEND -- END STATEMENT PROCESSOR
                  ;
84C2  F016 ^84DA  XEND    BEQ     :XE090          ; SYNTAX SCAN ONLY.

84C4  AE4D05              LDX     USTKP           ; USE STACK POINTER.
84C7  F014 ^84DD          BEQ     :XE095          ; STACK EMPTY.

84C9  86FF                STX     RUN             ; SET RUN MODE EVEN IF ALREADY SET.
84CB  CA                  DEX                     ; GET NEXT LINE ADDRESS FROM STACK.
84CC  CA                  DEX
84CD  8E4D05              STX     USTKP
84D0  BD6B05              LDA     USESTK,X
84D3  8584                STA     NXTLN
84D5  BD6C05              LDA     USESTK+1,X
84D8  8585                STA     NXTLN+1

84DA  A900        :XE090  LDA     #0              ; O.K. -- SET CC FOR EXIT.

84DC  60                  RTS

84DD  208198      :XE095  JSR     CLOSEM          ; CLOSE ALL OPEN FILES.
84E0  84AB                STY     XTEMP
84E2  209E98              JSR     REMDEV
84E5  A4AB                LDY     XTEMP
84E7  A981                LDA     #ENDERR         ; STOP CONDITION.
84E9  8D4305              STA     NOCONT          ; NO CONTINUE AFTER END.
84EC  60                  RTS


84ED                      PROC
                  ;
                  ; XSTOP -- STOP COMMAND PROCESSOR
                  ;
84ED  F002 ^84F1  XSTOP   BEQ     :XS090          ; SYNTAX SCAN ONLY.

84EF  A99A                LDA     #STPMES         ; GENERATE STOP MESSAGE.

84F1  60          :XS090  RTS



      = 0000              IF      DOS
   -                      PROC
                  ;
                  ; XDOS -- DOS COMMAND PROCESSOR
                  ;
   -              XDOS    BEQ     :XD090          ; SYNTAX SCAN ONLY.
   -                      STA     COLDST          ; SETUP FOR COLDSTART ON RESET.
   -                      JSR     TXOPEN          ; OPEN TEXT SCREEN.
   -                      JMP     (DSVSAV)        ; YES.

   -              :XD090  RTS
                          ENDIF

84F2                      PROC
                  ;
                  ; XRUN -- RUN COMMAND PROCESSOR
                  ;

84F2  20139F      XRUN    JSR     SLB             ; 'RUN <EOL>'?
84F5  20F99E              JSR     CHKTRM
84F8  F011 ^850B          BEQ     :XR005          ; YES.

                  ; ASSUME 'RUN <FILE>' - SHARP 'LOAD' CODE.


84FA  201090              JSR     XLO100          ; OPEN DEVICE.
84FD  D034 ^8533          BNE     :XR090          ; ERROR.

84FF  A592                LDA     EXEC            ; EXECUTE MODE?
8501  F005 ^8508          BEQ     :XR003          ; NO.

8503  85FF                STA     RUN             ; YES -- SET RUN MODE.
8505  201485              JSR     :XR020          ; INITIALIZE ENVIRONMENT.

8508  4C0190      :XR003  JMP     XLO005          ; NOW LET LOAD DO THE SETUP.

850B  A592        :XR005  LDA     EXEC            ; EXECUTE MODE?
850D  F024 ^8533          BEQ     :XR090          ; NO.

850F  85FF                STA     RUN             ; YES -- ENTER RUN MODE.

                  ; *** EXTERNAL ENTRY POINT FROM 'MLOOP' ***

8511  20A087      XRN010  JSR     XNEWV           ; CLEAR ALL VARIABLES.

8514  A5AE        :XR020  LDA     S1L             ; SETUP THE NEXT LINE POINTER.
8516  8584                STA     NXTLN
8518  A5AF                LDA     S1L+1
851A  8585                STA     NXTLN+1

851C  20A0A3              JSR     GCLEAR          ; CLEAR SCREEN.
851F  2060AF              JSR     GPINIT          ; INITIALIZE GRAPHICS PARAMETERS

8522  84AB                STY     XTEMP
8524  20729F              JSR     NULACC          ; SET ACCEPT BUFFER TO NULL.
8527  A4AB                LDY     XTEMP

8529  A900                LDA     #0              ; MAKE MATCH FLAG FALSE ...
852B  8D4D05              STA     USTKP           ; ... USE STACK INDEX ...
852E  85FE                STA     MATCHF          ; ... & SET CC ALSO.
8530  8D4305              STA     NOCONT          ; CONTINUE O.K.

8533  60          :XR090  RTS

8534                      PROC
                  ;
                  ; XCONT -- CONTINUE COMMAND PROCESSOR
                  ;
8534  F009 ^853F  XCONT   BEQ     :XC090          ; SYNTAX SCAN ONLY.

8536  AE4305              LDX     NOCONT          ; CONTINUE O.K.?
8539  D005 ^8540          BNE     :XC100          ; NO -- INFORM OPERATOR.


853B  85FF                STA     RUN             ; YES -- ENTER RUN MODE.
853D  A900                LDA     #0              ; SET CC FOR NORMAL RETURN.

853F  60          :XC090  RTS

8540  A999        :XC100  LDA     #CNTERR         ; CONTINUE ERROR.
8542  60                  RTS

8543                      PROC
                  ;
                  ; XACCPT -- ACCEPT COMMAND PROCESSOR
                  ;

8543  A900        XACCPT  LDA     #0              ; STANDARD ACCFPT.
8545  8D4705              STA     AKFLAG
8548  8D4605              STA     AXFLAG

                  ; *** EXTERNAL ENTRY POINT FROM 'XACCX' AND 'XACCK' ***

854B  20009F      :XA001  JSR     CHKEQS          ; '='?
854E  D006 ^8556          BNE     :XA003          ; NO OR NOT YET.

8550  A901                LDA     #NULL           ; SETUP FOR NULL TARGET.
8552  85AB                STA     XTEMP
8554  D051 ^85A7          BNE     :XA022          ; (BRA).

8556  206E81      :XA003  JSR     ATOM            ; CHECK FOR VARIABLE.
8559  D008 ^8563          BNE     :XA009          ; ERROR.

855B  85AB                STA     XTEMP           ; SAVE ATOM TYPE.
855D  299D                AND     #SVAR+USVAR+NVAR+NULL+BPTR
855F  D003 ^8564          BNE     :XA020          ; VALID ATOM TYPE.

8561  A902                LDA     #IMPERR         ; NONE OF THE ABOVE -- ERROR.

8563  60          :XA009  RTS                     ; RETURN WITH CC SET.

8564  20BB8B      :XA020  JSR     SAVIT           ; YES -- SAVE NAME IF STRING TARGET.

8567  20009F      :XA20D  JSR     CHKEQS          ; CHECK FOR ASSIGNMENT OPTION.
856A  F03B ^85A7          BEQ     :XA022          ; YES.

856C  A592                LDA     EXEC            ; EXECUTE MODE?
856E  F0F3 ^8563          BEQ     :XA009          ; NO.

8570  84AC                STY     XTEMP+1         ; SAVE STATEMENT INDFX.
8572  AD4705              LDA     AKFLAG          ; ACCEPT KEY?
8575  D017 ^858E          BNE     :XA021          ; YES.

8577  20BB96              JSR     TSTMOD          ; CHECK SCREEN MODE.
857A  2905                AND     #TXSL+GRSS      ; TEXT INPUT O.K.?
857C  D003 ^8581          BNE     :XA20G          ; YES.

857E  A983                LDA     #NRCERR         ; NO -- ERROR.
8580  60                  RTS

8581  A20C        :XA20G  LDX     #TELN-DTAB      ; GET A LINE TO THE TEXP BUFFER.
8583  20B194              JSR     GETLIN

8586  C68F                DEC     TELN+3          ; REMOVE EOL.
8588  2028A1              JSR     TRAILB          ; PROCESS UNDERSCORE IF PRESENT.
858B  4CC785              JMP     :XA024

858E  A900        :XA021  LDA     #0
8590  A8                  TAY
8591  858A                STA     ACLN+2
8593  858E                STA     TELN+2
8595  A920                LDA     #' '            ; LEADING BLANK.
8597  9188                STA     (ACLN),Y
8599  207497              JSR     KIN             ; GET KEY.
859C  918C                STA     (TELN),Y
859E  C8                  INY
859F  848F                STY     TELN+3
85A1  9188                STA     (ACLN),Y
85A3  C8                  INY
85A4  4C1686              JMP     :XA030

85A7  C8          :XA022  INY                     ; YES -- SKIP OVER '='.
85A8  A5B6                LDA     POINT           ; SAVE 'POINT'.
85AA  8D4905              STA     GNUMB
85AD  A5B7                LDA     POINT+1
85AF  8D4A05              STA     GNUMB+1

85B2  20A7A0              JSR     TEXP            ; EVALUATE TEXT EXPRESSION.

85B5  A592                LDA     EXEC            ; EXECUTE MODE?
85B7  F0AA ^8563          BEQ     :XA009          ; NO.

85B9  84AC                STY     XTEMP+1         ; YES -- RESTORE 'NP'.
85BB  A4AC                LDY     XTEMP+1
85BD  AD4905              LDA     GNUMB           ; RESTORE 'POINT'.
85C0  85B6                STA     POINT
85C2  AD4A05              LDA     GNUMB+1
85C5  85B7                STA     POINT+1

                  ; *** EXTERNAL ENTRY POINT FROM 'XIN' ***

                  ;       EXPECTS: STATEMENT INDEX IN 'XTEMP+1'.
                  ;                TARGET ATOM TYPE IN 'XTEMP'.
                  ;                'POINT' OR 'NP' SETUP PER 'ATOM' CALL.
                  ;                'AXFLAG' SET PROPERLY.
                  ;                'SAVIT' CALLED IF STRING TARGET.
                  ;                STRING DATA IN 'TEXP'.
85C7              XAC024
85C7  20FF8B      :XA024  JSR     RESIT           ; YES -- RESTORE NAME IF STRING TARGET.

85CA  A58E                LDA     TELN+2          ; MOVE START INDEX.
85CC  858A                STA     ACLN+2
85CE  AA                  TAX
85CF  A8                  TAY
85D0  AD4605              LDA     AXFLAG          ; ACCEPT LITERAL?
85D3  F012 ^85E7          BEQ     :XA24T          ; NO.

85D5  E48F        :XA24D  CPX     TELN+3          ; DONE?
85D7  F042 ^861B          BEQ     :XA031          ; YES.

85D9  BD00BC              LDA     TEXBUF,X        ; NO -- GET NEXT CHAR.
85DC  E8                  INX

85DD  C0FE                CPY     #ACCLNG         ; ACCEPT BUFFER FULL?
85DF  F03A ^861B          BEQ     :XA031          ; YES.

85E1  9188                STA     (ACLN),Y
85E3  C8                  INY
85E4  4CD585              JMP     :XA24D

85E7  A920        :XA24T  LDA     #' '             ; INSERT LEADING BLANK.
85E9  D016 ^8601          BNE     :XA027          ; (BRA).

85EB  E48F        :XA025  CPX     TELN+3          ; DONE?
85ED  F027 ^8616          BEQ     :XA030          ; YES.

85EF  BD00BC              LDA     TEXBUF,X        ; NO -- GET NEXT CHAR.
85F2  E8                  INX

85F3  C0FD        :XA026  CPY     #ACCLNG-1
85F5  F01F ^8616          BEQ     :XA030          ; ACCEPT BUFFER FULL.

                  ; CHARACTER CONVERSION HERE.

85F7  C961                CMP     #'A'+$20         ; LOWER CASE ALPHA?
85F9  9006 ^8601          BCC     :XA027          ; NO

85FB  C97B                CMP     #'Z'+1+$20
85FD  B002 ^8601          BCS     :XA027          ; NO.

85FF  4920                EOR     #$20            ; YES -- CONVERT TO UPPER CASE.

8601  9188        :XA027  STA     (ACLN),Y
8603  C8                  INY

8604  C920                CMP     #' '             ; BLANK?
8606  D0E3 ^85EB          BNE     :XA025          ; NO.

8608  E48F        :XA028  CPX     TELN+3          ; YES -- SKIP MULTIPLES.
860A  F00F ^861B          BEQ     :XA031          ; END OF TEXT.

860C  BD00BC              LDA     TEXBUF,X        ; GET NEXT CHARACTER.
860F  E8                  INX
8610  C920                CMP     #' '             ; BLANK?
8612  D0DF ^85F3          BNE     :XA026          ; NO -- STORE IT.

8614  F0F2 ^8608          BEQ     :XA028          ; YES -- IGNORE IT (BRA).

8616  A920        :XA030  LDA     #' '             ; ADD TRAILING BLANK.
8618  9188                STA     (ACLN),Y
861A  C8                  INY

861B  848B        :XA031  STY     ACLN+3          ; END INDEX.

861D  A5AB                LDA     XTEMP           ; CHECK PARAMETER TYPE AGAIN.
861F  C901                CMP     #NULL
8621  F02F ^8652          BEQ     :XA190          ; NONE -- ALL DONE.

8623  2984                AND     #NVAR+BPTR
8625  D003 ^862A          BNE     :XA100          ; NUMERIC VARIABLE.

8627  4CA78B              JMP     XCM300          ; STRING VARIABLE -- GO TO COMMON CODE & RET.

862A  A0FF        :XA100  LDY     #-1             ; CONVERT NUMBER TO BINARY REPRESENTATION.

862C  C8          :XA110  INY                     ; SCAN TO NUMBER OR EOL.
862D  B18C                LDA     (TELN),Y        ; GET A CHAR.
862F  C99B                CMP     #EOL            ; END OF LINE?
8631  F009 ^863C          BEQ     :XA120          ; YES -- DONE.

8633  C92D                CMP     #'-'             ; NO -- MINUS SIGN?
8635  F005 ^863C          BEQ     :XA120          ; YES -- DONE.

8637  20839E              JSR     CNUMBR          ; NO -- NUMERIC DIGIT?
863A  B0F0 ^862C          BCS     :XA110          ; NO -- KEEP SCANNING.

863C  A20C        :XA120  LDX     #TELN-DTAB      ; NOW CONVERT NUMBER WE FOUND.
863E  20BB9D              JSR     ASCDEC

8641  A000                LDY     #0              ; MOVE VALUE TO VARIABLE.
8643  A5B8                LDA     NUMBER
8645  91B6                STA     (POINT),Y
8647  A5AB                LDA     XTEMP           ; SEE IF POINTER TO BYTE.
8649  C980                CMP     #BPTR
864B  F005 ^8652          BEQ     :XA190          ; YES -- ALL DONE.

864D  C8                  INY
864E  A5B9                LDA     NUMBER+1
8650  91B6                STA     (POINT),Y

8652  A4AC        :XA190  LDY     XTEMP+1         ; RESTORE LINE POINTER.
8654  A900                LDA     #0              ; SET CC FOR NORMAL EXIT.
8656  60                  RTS                     ; RETURN WITH CC SET.

                  ;
                  ; XACCX -- ACCEPT LITERAL COMMAND PROCESSOR.
                  ;
8657  A901        XACCX   LDA     #1
8659  8D4605              STA     AXFLAG
865C  A900                LDA     #0
865E  8D4705              STA     AKFLAG
8661  4C4B85              JMP     :XA001

                  ;
                  ; XACCK -- ACCEPT PROM KEYBOARD (SINGLE CHARACTER).
                  ;
8664  A901        XACCK   LDA     #1
8666  8D4705              STA     AKFLAG
8669  4C4B85              JMP     :XA001

866C                      PROC
                  ;
                  ; XMATCH -- PATCH COMMAND PROCESSOR
                  ;
866C  A900        XMATCH  LDA     #0              ; FORCE UPPER CASE ALPHA.
866E  F002 ^8672          BEQ     :XM005

8670  A901        XMATX   LDA     #1              ; LITERAL MATCH.

8672  8DDA05      :XM005  STA     LITMAT

8675  B180                LDA     (INLN),Y        ; GET FIRST MATCH FIELD BYTE.
8677  C99B                CMP     #EOL
8679  D003 ^867E          BNE     :XM010

867B  A902                LDA     #IMPERR         ; NULL MATCH FIELD IS ERROR.

867D  60          :XM009  RTS                     ; RETURN WITH CC SET.

867E  20A7A0      :XM010  JSR     TEXP            ; EVALUATE TEXT EXPRESSION OPERAND.

8681  A592                LDA     EXEC            ; EXECUTE MODE?
8683  F0F8 ^867D          BEQ     :XM009          ; NO -- DONE.

8685  A900                LDA     #0              ; RESET MATCH FIELD NUMBER AND FLAG.
8687  85FE                STA     MATCHF

8689  A92C                LDA     #','            ; IS DEFAULT MATCH FIELD DELIMITER.
868B  85E2                STA     MFDEL

868D  84AC                STY     XTEMP+1         ; SAVE INPUT INDEX.
868F  A58E                LDA     TELN+2          ; CHECK FOR NULL RESULT.
8691  C58F                CMP     TELN+3
8693  D003 ^8698          BNE     :XM011
8695  4C2387              JMP     :XM400          ; NULL PATTERN -- NO MATCH.

8698  ADDA05      :XM011  LDA     LITMAT          ; LITERAL MATCH?
869B  D012 ^86AF          BNE     :XM020          ; YES.

869D  A48E                LDY     TELN+2          ; NO -- FORCE UPPER CASE ALPHA.

869F  B18C        :XM012  LDA     (TELN),Y        ; GET CHAR.
86A1  20919E              JSR     CLETTR          ; IS IT A LETTER?
86A4  B004 ^86AA          BCS     :XM015          ; NO.

86A6  29DF                AND     #UC             ; YESS -- FORCE UPPER CASE.
86A8  918C                STA     (TELN),Y

86AA  C8          :XM015  INY                     ; NEXT CHAR.
86AB  C48F                CPY     TELN+3          ; DONE?
86AD  D0F0 ^869F          BNE     :XM012          ; NO.

                  ; THROUGHOUT THE MAIN LOOP THE X REGISTER WILL = ACCEPT START INDEX.

86AF  A68A        :XM020  LDX     ACLN+2          ; ACCEPT BUFFER START INDEX.
86B1  A48E                LDY     TELN+2          ; SETUP MATCH PATTERN START INDEX.


86B3  B18C                LDA     (TELN),Y        ; CHECK FOR ALTERNATE FIELD DELIMITER.
86B5  C97C                CMP     #VBAR
86B7  D005 ^86BE          BNE     :XM050          ; NO ALTERNATE SPECIFIED

86B9  85E2                STA     MFDEL           ; SET ALTERNATE.
86BB  C8                  INY                     ; SKIP OVER VERTICAL BAR.
86BC  D00C ^86CA          BNE     :XM060          ; (BRA).

86BE  B18C        :XM050  LDA     (TELN),Y        ; GET 1ST CHAR OF OPERAND.
86C0  C91F                CMP     #CRIGHT         ; RIGHT ARROW?
86C2  D00C ^86D0          BNE     :XM100          ; NO.

86C4  E8                  INX                     ; YES -- SKIP FIRST CHAR IK ACCEPT BUFFER.
86C5  C8                  INY                     ; SKIP OVER RIGHT ARROW TOO.

86C6  E48B                CPX     ACLN+3          ; NULL ACCEPT BUFFER?
86C8  F059 ^8723          BEQ     :XM400          ; YES -- NO MATCH.

86CA  C48F        :XM060  CPY     TELN+3          ; NULL OPERAND?
86CC  F055 ^8723          BEQ     :XM400          ; YES.

86CE  D0EE ^86BE          BNE     :XM050          ; NO (BRA).

86D0  84AB        :XM100  STY     XTEMP           ; MATCH DATA INDEX (INNER LOOP).
86D2  84A2                STY     TEMP+1          ; MATCH DATA INDEX (OUTER LOOP).

86D4  86A1                STX     TEMP
86D6  868A                STX     ACLN+2
86D8  E6FE                INC     MATCHF          ; INCREMENT MATCH FIELD NUMBER.

86DA  A4AB        :XM120  LDY     XTEMP           ; SEE IF ALL OF PATTERN HAS HATCHED.
86DC  E6AB                INC     XTEMP
86DE  C48F                CPY     TELN+3
86E0  F037 ^8719          BEQ     :XM300          ; YES.

86E2  B18C                LDA     (TELN),Y        ; NOT SURE.
86E4  C5E2                CMP     MFDEL
86E6  F031 ^8719          BEQ     :XM300          ; YES.

86E8  A48A                LDY     ACLN+2          ; NO -- MORE DATA TO MATCH?
86EA  E68A                INC     ACLN+2
86EC  C48B                CPY     ACLN+3
86EE  F004 ^86F4          BEQ     :XM140          ; NO -- AT END OF BUFFER.

86F0  D188                CMP     (ACLN),Y        ; YES -- COMPARE DATA TO PATTERN.
86F2  F0E6 ^86DA          BEQ     :XM120          ; SO FAR SO GOOD.

86F4  A5A2        :XM140  LDA     TEMP+1          ; RESET MATCH PATTERN INDEX.
86F6  85AB                STA     XTEMP
86F8  E6A1                INC     TEMP            ; INCREMENT #ACCBUF' INDEX.
86FA  A5A1                LDA     TEMP
86FC  858A                STA     ACLN+2
86FE  C58B                CMP     ACLN+3
8700  D0D8 ^86DA          BNE     :XM120

8702  A4A2                LDY     TEMP+1          ; INCREMENT 'TEXBUP' INDEX TO NEXT FIELD.

8704  B18C        :XM160  LDA     (TELN),Y
8706  C48F                CPY     TELN+3          ; END OF MATCH PATTERN DATA?
8708  F009 ^8713          BEQ     :XM200          ; YES -- NO MATCH.

870A  C8                  INY
870B  C5E2                CMP     MFDEL
870D  D0F5 ^8704          BNE     :XM160          ; KEEP SCANNING.

870F  C48F                CPY     TELN+3          ; END OF MATCH STATEMENT?
8711  D0BD ^86D0          BNE     :XM100          ; NO.

8713  A900        :XM200  LDA     #0              ; NO MATCH -- RESET FLAG.
8715  85FE                STA     MATCHF
8717  F00A ^8723          BEQ     :XM400          ; (BRA).

8719  A5A1        :XM300  LDA     TEMP            ; SAVE START & END INDICES TO MATCH FIELD ...
871B  8D3305              STA     MATCHX          ; ... FOR 'XMWSP'.
871E  A58A                LDA     ACLN+2
8720  8D3405              STA     MATCHX+1

8723  A4AC        :XM400  LDY     XTEMP+1         ; RESTORE INPUT LINE INDEX.

8725  A900                LDA     #0              ; CLEAR LINE INDEX.
8727  858A                STA     ACLN+2
8729  4C1B9F              JMP     SCNEOL          ; SCAN TO END OF INPUT LINE & RETURN.


872C                      PROC
                  ;
                  ; XMWSP -- MATCH WITH STRING PRODUCTION COMMAND PROCESSOR
                  ;
872C  207086      XMATSX  JSR     XMATX
872F  4C3587              JMP     :XM005

8732  206C86      XMWSP   JSR     XMATCH          ; FIRST DO ALL OF MATCH COMMAND.
8735  D035 ^876C  :XM005  BNE     :XM090          ; SYNTAX ERROR.

8737  A592                LDA     EXEC            ; EXECUTE MODE?
8739  F031 ^876C          BEQ     :XM090          ; NO -- DONE (SYNTAX SAME AS NATCH).

873B  A5FE                LDA     MATCHF          ; WAS MATCH SUCCESSFUL?
873D  F02D ^876C          BEQ     :XM090          ; NO -- ALL DONE.

873F  84AB                STY     XTEMP
8741  A980                LDA     #ATRSTR         ; 'STRING' ATTRIBUTE.
8743  8D6605              STA     ATRTYP
8746  8A                  TXA                     ; NOW SET SLEFT = DATA FROM ACCEPT START ...
8747  AC3305              LDY     MATCHX          ; ... TO START OF MATCH - 1.
874A  A200                LDX     #LFTSTG-STAB
874C  206D87              JSR     MAKSTG
874F  D017 ^8768          BNE     :XM080          ; ERROR.

8751  AD3305              LDA     MATCHX          ; THEN SET SMATCH = DATA FROM MATCH.
8754  AC3405              LDY     MATCHX+1
8757  A205                LDX     #MATSTG-STAB
8759  206D87              JSR     MAKSTG
875C  D00A ^8768          BNE     :XM080          ; ERROR.

875E  AD3405              LDA     MATCHX+1        ; THEN $RIGHT = DATA FROM MATCH +1 ...
8761  A48B                LDY     ACLN+3          ; ... TO END.
8763  A20B                LDX     #RITSTG-STAB
8765  206D87              JSR     MAKSTG

8768  08          :XM080  PHP                     ; SAVE CC.
8769  A4AB                LDY     XTEMP           ; RESTORE INDEX.
876B  28                  PLP

876C  60          :XM090  RTS                     ; RETURN WITH CC SET.


876D  85C4        MAKSTG  STA     DP+2            ; DEFINE DATA PORTION.
876F  84C5                STY     DP+3
8771  A588                LDA     ACLN
8773  85C2                STA     DP
8775  A589                LDA     ACLN+1
8777  85C3                STA     DP+1

8779  BD8F87              LDA     STAB,X          ; DEFINE NAME PORTION.
877C  85C1                STA     NP+3
877E  E8                  INX
877F  86C0                STX     NP+2
8781  A98F                LDA     # LOW STAB
8783  85BE                STA     NP
8785  A987                LDA     # HIGH STAB
8787  85BF                STA     NP+1

8789  20AD9E              JSR     SETSVL          ; NAMED STRING VARIABLE LIST.

878C  4C0599              JMP     SINSRT          ; INSERT STRING & RETURN WITH CC SET.

      = 878F      STAB = *                          ; MATCH STRING NAME TABLE.

878F  054C454654  LFTSTG  DB   LSEND,'LEFT'
      = 0005      LSEND = *-STAB

8794  0B4D415443  MATSTG  DB   MSEND,'MATCH'
      = 000B      MSEND = *-STAB

879A  1152494748  RITSTG  DB   RSEND,'RIGHT'
      = 0011      RSEND = *-STAB

87A0                      PROC
                  ;
                  ; XNEWV -- NEW VARIABLES COMMAND PROCESSOR
                  ;
87A0  A592        XNEWV   LDA     EXEC            ; EXECUTE MODE?
87A2  F012 ^87B6          BEQ     :XN090          ; SYNTAX SCAN ONLY.

87A4  A5B4                LDA     S2H             ; CLEAR MOD VARIABLES.
87A6  85B2                STA     S2L
87A8  A5B5                LDA     S2H+1
87AA  85B3                STA     S2L+1

87AC  208198              JSR     CLOSEM          ; CLOSE IOCBS 3 THROUGH 7.

87AF  A5FF                LDA     RUN             ; RUN MODE?
87B1  D003 ^87B6          BNE     :XN090          ; YES -- DON'T PRINT 'READY'.

87B3  202CB5              JSR     RDYMES          ; NO -- PRINT 'READY'.

87B6              XNE090
87B6  A900        :XN090  LDA     #0              ; SET CC FOR EXIT.
87B8  60                  RTS                     ; RETURN WITH CC SET.

87B9                      PROC
                  ;
                  ; XNEW -- NEW PROGRAM PROCESSOR
                  ;
87B9  F0FB ^87B6  XNEW    BEQ     XNE090          ; SYNTAX SCAN ONLY.

87BB  20C087              JSR     CLRPRG          ; CLEAR THE PROGRAM STORAGE AREA.
87BE  F0E0 ^87A0          BEQ     XNEWV           ; (BRA) NOW CLEAR THE VARIABLES ALSO

87C0  A5AE        CLRPRG  LDA     S1L             ; YES -- CLEAR PROGRAM STORAGE AREA.
87C2  85B0                STA     S1H
87C4  A5AF                LDA     S1L+1
87C6  85B1                STA     S1H+1
87C8  A9FF                LDA     #$FF            ; NO CONTINUATION.
87CA  8D4305              STA     NOCONT

87CD  A900                LDA     #0
87CF  8D4D05              STA     USTKP           ; CLEAR USE STACK.
87D2  60                  RTS                     ; RETURN WITH CC AND A = ZERO.


87D3                      PROC
                  ;
                  ; XCALL -- CALL MEMORY LOCATION PROCESSOR
                  ;
87D3  20D49F      XCALL   JSR     EXP             ; ADDRESS SHOULD FOLLOW.

87D6  A592                LDA     EXEC            ; EXECUTE MODE?
87D8  F00B ^87E5          BEQ     :XC090          ; NO.

87DA  98                  TYA                     ; SAVE THE LINE INDEX FOR THE USER.
87DB  48                  PHA

87DC  20E687              JSR     :XC100          ; "OFF WE GO, INTO THE WILD BLUE YONDER".

87DF  68                  PLA                     ; UNBELIEVEABLE, THE USER RETURNED.
87E0  A8                  TAY                     ; RESTORE THE LINE INDEX.
87E1  58                  CLI                     ; JUST IN CASE!
87E2  D8                  CLD                     ; DITTO.

87E3  A900                LDA     #0              ; SET CC FOR EXIT.
87E5  60          :XC090  RTS                     ; RETURN WITH CC SET.

87E6  6C9300      :XC100  JMP     (EXPSTK)        ; TOO LATE TO CHANGE YOUR MIND.


87E9                      PROC
                  ;
                  ; XUSE -- USE COMMAND PROCESSOR
                  ;

87E9  F024 ^880F  XUSE    BEQ     XJMP            ; LET 'XJMP' PERFORM SYNTAX CHECK.

87EB  A5FF                LDA     RUN             ; IF IMMEDIATE -- DON'T PUT ANYTHING IN STACK
87ED  F01B ^880A          BEQ     :XU100

87EF  AE4D05              LDX     USTKP           ; USE STACK POINTER.
87F2  E030                CPX     #USTKSZ
87F4  F011 ^8807          BEQ     :XU090          ; STACK FULL.

87F6  A584                LDA     NXTLN           ; NEXT LINE ADDRESS TO USE STACK.
87F8  9D6B05              STA     USESTK,X
87FB  A585                LDA     NXTLN+1
87FD  9D6C05              STA     USESTK+1,X
8800  E8                  INX
8801  E8                  INX
8802  8E4D05              STX     USTKP
8805  D00D ^8814          BNE     XJP005          ; REST OF COMMAND IS JUST LIKE 'J:' (BRA).

8807  A98B        :XU090  LDA     #USOERR         ; STACK OVERFLOW ERROR.
8809  60                  RTS

880A  8D4D05      :XU100  STA     USTKP           ; CLEAR USE STACK.
880D  F005 ^8814          BEQ     XJP005          ; (BRA).


880F                      PROC
                  ;
                  ; XJMP -- JUMP COMMAND PROCESSOR
                  ;
880F  D003 ^8814  XJMP    BNE     XJP005          ; EXECUTE MODE.

8811  4CD39E              JMP     SCNLBL          ; SCAN OVER LABEL & RETURN.


                  ; *** EXTERNAL ENTRY POINT (FROM 'XJMPM' & 'XUSE') ***

8814  20139F      XJP005  JSR     SLB
8817  C8                  INY                     ; SKIP OVER '*'.
8818  84C4                STY     DP+2            ; SETUP 'DP' TO POINT TO JUMP LABEL.
881A  20CB9E              JSR     SCEOA           ; SCAN TO END OF LABEL.
881D  84C5                STY     DP+3
881F  A580                LDA     INLN
8821  85C2                STA     DP
8823  A581                LDA     INLN+1
8825  85C3                STA     DP+1

8827  209F9E              JSR     STMLST          ; SETUP TO SCAN STATEMENT LIST.
882A  84AB                STY     XTEMP           ; SAVE INPUT LINE POINTER.

882C  A23A        :XJ030  LDX     #LP-DTAB        ; CHECK FOR END OF STATEMENT LIST.
882E  20139A              JSR     SEND
8831  F040 ^8873          BEQ     :XJ200          ; END OF LIST -- LABEL NOT FOUND.

8833  A006                LDY     #6              ; CHECK FOR PRESENCE OF LABEL.
8835  B1BA        :XJ032  LDA     (LP),Y
8837  C920                CMP     #' '            ; BLANK?
8839  D003 ^883E          BNE     :XJ034          ; NO.
883B  C8                  INY                     ; SKIP LEADING BLANKS.
883C  D0F7 ^8835          BNE     :XJ032          ; (BRA).

883E  C92A        :XJ034  CMP     #'*'
8840  D029 ^886B          BNE     :XJ060          ; NO -- TRY NEXT STATEMENT.

8842  C8                  INY
8843  84C8                STY     MP+2            ; YES -- SETUP 'MR' TO POINT TO STATEMENT LABEL.

8845  B1BA        :XJ040  LDA     (LP),Y          ; SCAN TO END OF LABEL.
8847  C8                  INY
8848  20B69E              JSR     CKEOA           ; END OF ATOM (LABEL)?
884B  D0F8 ^8845          BNE     :XJ040          ; NO.

884D  88                  DEY
884E  84C9                STY     MP+3

8850  A5BA                LDA     LP              ; SETUP POINTERS FOR ...
8852  85C6                STA     MP              ; 'SCOMP' CALL ...
8854  8584                STA     NXTLN           ; ... & STATEMENT TO EXECUTE.
8856  A5BB                LDA     LP+1
8858  85C7                STA     MP+1
885A  8585                STA     NXTLN+1
885C  205599              JSR     SCOMP           ; COMPARE LABELS.
885F  D00A ^886B          BNE     :XJ060          ; NO MATCH.

8861  A4AB                LDY     XTEMP           ; RESTORE INPUT LINE POINTER.
8863  84FF                STY     RUN             ; SET RUN MODE EVEN IF ALREADY SET
8865  A900                LDA     #0
8867  8D4305              STA     NOCONT
886A  60                  RTS                     ; RETURN WITH CC SET.

886B  A23A        :XJ060  LDX     #LP-DTAB        ; GET POINTER TO NEXT STATEMENT.
886D  20AA9A              JSR     SNXTI
8870  4C2C88              JMP     :XJ030

8873  A4C4        :XJ200  LDY     DP+2            ; RESTORE LINE INDEX.
8875  A90A                LDA     #UNDERR         ; UNDEFINED LABEL.
8877  60                  RTS                     ; RETURN WITH CC SET.

8878                      PROC
                  ;
                  ; XJMPM -- JUMP ON MATCH RESULT COMMAND PROCESSOR
                  ;
8878  D00C ^8886  XJMPM   BNE     :XJ030          ; EXECUTE MODE.

887A  20D39E              JSR     SCNLBL          ; SCAN OVER FIRST LABEL.
887D  D026 ^88A5          BNE     :XJ090          ; NOT EVEN ONE LABEL -- ERROR.

887F  20D39E      :XJ010  JSR     SCNLBL          ; SCAN OVER REMAINING LABELS.
8882  F0FB ^887F          BEQ     :XJ010

8884  D01D ^88A3          BNE     :XJ050          ; NORMAL RETURN.



8886  A5FE        :XJ030  LDA     MATCHF          ; WAS PREVIOUS MATCH SUCCESSFUL?
8888  F011 ^889B          BEQ     :XJ043          ; NO -- NO JUMP.

888A  AA                  TAX                     ; YES -- USE FIELD U AS LOOP COUNT.

888B  CA          :XJ040  DEX
888C  D010 ^889E          BNE     :XJ045          ; NOT THERE YET.

888E  20079F              JSR     SKPSEP          ; PRE-VALIDATE NEXT LABEL.
8891  20F99E              JSR     CHKTRM          ; END OF STATEMENT?
8894  F00F ^88A5          BEQ     :XJ090          ; YES -- O.K.

8896  201488              JSR     XJP005          ; LET 'XJMP' DO THE DIRTY WORK.
8899  D00A ^88A5          BNE     :XJ090          ; ERROR.

889B  4C1B9F      :XJ043  JMP     SCNEOL          ; SCAN TO END OF STATEMENT & RETURN

889E  20D39E      :XJ045  JSR     SCNLBL          ; SCAN OVER LABEL.
88A1  F0E8 ^888B          BEQ     :XJ040          ; THERE WAS ONE THERE.

88A3  A900        :XJ050  LDA     #0              ; TOO FEW LABELS IS O.K.

88A5  60          :XJ090  RTS                     ; RETURN WITH CC SET.


88A6                      PROC
                  ;
                  ; XDUMP -- STRING & NUMERIC VARIABLE DUMP COMMAND PROCESSOR
                  ;
88A6  20139F      XDUMP   JSR     SLB             ; SKIP LEADING BLANKS.
88A9  20F99E              JSR     CHKTRM          ; STATEMENT TERMINATOR?
88AC  F00C ^88BA          BEQ     :XD020          ; YES.

88AE  C923                CMP     #'#'
88B0  F007 ^88B9          BEQ     :XD010          ; NUMERIC VARIABLES ONLY.

88B2  C924                CMP     #'$'
88B4  F003 ^88B9          BEQ     :XD010          ; STRING VARIABLES ONLY.

88B6  A902                LDA     #IMPERR         ; IMPROPER OPERAND.
88B8  60          :XD009  RTS                     ; RETURN WITH CC SET.

88B9  C8          :XD010  INY

88BA  85AB        :XD020  STA     XTEMP           ; SAVE OPERAND
88BC  A592                LDA     EXEC
88BE  F0F8 ^88B8          BEQ     :XD009          ; SYNTAX SCAN.

88C0  84AC                STY     XTEMP+1         ; YES -- SAVE INPUT LINE INDEX.
88C2  A97D                LDA     #CLEAR          ; CLEAR SCREEN.
88C4  208294              JSR     CHOT
88C7  CEFE02              DEC     DSPFLG          ; SET DISPLAY CONTROL CHARS FLAG.

                  ; DUMP ALL OF THE STRING VARIABLES

88CA  A5AB                LDA     XTEMP           ; CHECK OPERAND.
88CC  C923                CMP     #'#'            ; NUMERIC ONLY?
88CE  F013 ^88E3          BEQ     :XD050          ; YES.

88D0  A910                LDA     #16             ; PRODUCE STRING VARIABLE HEADER.
88D2  20FFB4              JSR     MESSOT

88D5  A980                LDA     #ATRSTR         ; STRINGS.
88D7  8D6705              STA     DMPTYP
88DA  208689              JSR     DMPVAR

                  ; DUMP ALL OF THE NUMERIC VARIABLES.

88DD  A5AB                LDA     XTEMP           ; CHECK OPERAND.
88DF  C924                CMP     #'$'            ; STRING ONLY.
88E1  F00D ^88F0          BEQ     :XD060          ; YES.

88E3  A911        :XD050  LDA     #17             ; NUMERIC VARIABLE HEADER.
88E5  20FFB4              JSR     MESSOT

88E8  A940                LDA     #ATRNUM         ; NUMERIC.
88EA  8D6705              STA     DMPTYP
88ED  208689              JSR     DMPVAR

                  ; DUMP THE I/O'S.

88F0  A5AB        :XD060  LDA     XTEMP           ; CHECK OPERATOR.
88F2  A4AC                LDY     XTEMP+1         ; RESTORE INDEX.
88F4  20F99E              JSR     CHKTRM          ; TERMINATOR?
88F7  D07D ^8976          BNE     :XD090          ; NO -- '$' OR '#'.

88F9  A923                LDA     #35             ; I/O HEADER.
88FB  20FFB4              JSR     MESSOT

88FE  A920                LDA     #ATRIO          ; I/O'S
8900  8D6705              STA     DMPTYP
8903  208689              JSR     DMPVAR

                  ; DUMP THE CONTENT OF THE STACK.

8906  A912                LDA     #18             ; PRODUCE USE STACK HEADER.
8908  20FFB4              JSR     MESSOT

890B  AE4D05              LDX     USTKP           ; STACK EMPTY?
890E  F01D ^892D          BEQ     :XD088          ; YES.

8910  20A29F      :XD087  JSR     SPACE           ; NO -- PRINT LINE #(S).
8913  BD6905              LDA     USESTK-2,X      ; GET POINTER TO STORED LINE
8916  85B6                STA     POINT
8918  BD6A05              LDA     USESTK-1,X
891B  85B7                STA     POINT+1

891D  208C9F              JSR     GTLNNO          ; EXTRACT LINE NUMBER.

8920  86AD                STX     XTEMP+2
8922  A25C                LDX     #LINENO-DTAB    ; PRINT LINE NUMBER.
8924  20149E              JSR     DECASC
8927  A6AD                LDX     XTEMP+2
8929  CA                  DEX
892A  CA                  DEX
892B  D0E3 ^8910          BNE     :XD087          ; MORE TO PRINT.

                  ; DUMP THE GRAPHICS PARAMETERS

892D  A913        :XD088  LDA     #19             ; PRODUCE GRAPHICS HEADER.
892F  20FFB4              JSR     MESSOT

8932  A958                LDA     #'X'            ; X=FLOOR(<VALUE>).
8934  208294              JSR     CHOT
8937  208189              JSR     PRTEQS          ; '='.
893A  A26C                LDX     #GX-DTAB
893C  20149E              JSR     DECASC
893F  209D9F              JSR     SPACES

8942  A959                LDA     #'Y'            ; Y=FLOOR(<VALUE>).
8944  208294              JSR     CHOT
8947  208189              JSR     PRTEQS          ; '='.
894A  A26F                LDX     #GY-DTAB
894C  20149E              JSR     DECASC
894F  209D9F              JSR     SPACES

8952  A914                LDA     #20             ; THETA=<VALUE>.
8954  20FFB4              JSR     MESSOT
8957  A272                LDX     #THETA-DTAB
8959  20149E              JSR     DECASC

                  ; REPORT ON FREE MEMORY

895C  A915                LDA     #21             ; FREE MEMORY = <VALUE>.
895E  20FFB4              JSR     MESSOT

8961  A032                LDY     #S2L-DTAB       ; <VALUE> = #'S2L' - 'S1H' + 1.
8963  20A29D              JSR     DLOADA
8966  A030                LDY     #S1H-DTAB
8968  20B19D              JSR     DSUBA
896B  A901                LDA     #1
896D  20049D              JSR     DADDS
8970  20149E              JSR     DECASC          ; PRINT RESULT.
8973  20989F              JSR     NEWLIN

8976  20989F      :XD090  JSR     NEWLIN          ; BLANK LINE AFTER DUMP.
8979  EEFE02              INC     DSPFLG          ; RESET DISPLAY CONTROL CHARS FLAG.
897C  A4AC                LDY     XTEMP+1         ; DONE -- RESTORE INPUT LINE INDEX.
897E  A900                LDA     #0              ; SET CC FOR EXIT.
8980  60                  RTS                     ; RETURN WITH CC SET.

8981  A93D        PRTEQS  LDA     #'='            ; PRINT '=' ...
8983  4C8294              JMP     CHOT            ; ... & RETURN.

8986                      PROC
                  ;
                  ; DMPVAR -- COMMON CODE FOR 'XDUMP'.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       DMPTYP = ATTRIBUTE TYPE
                  ;
                  ;       JSR DMPVAR
                  ;
8986  20AD9E      DMPVAR  JSR     SETSVL          ; POINT TO VARIABLE LIST.

8989  A23A        :DM010  LDX     #LP-DTAB
898B  20139A              JSR     SEND            ; END OF STRING STORAGE?
898E  F060 ^89F0          BEQ     :DM090          ; YES -- DONE.

                  ; *S*   LDX     #LP-DTAB
8990  20869A              JSR     SATTR           ; CORRECT TYPE?
8993  CD6705              CMP     DMPTYP
8996  D050 ^89E8          BNE     :DM080          ; NO.

8998  A238                LDX     #NUMBER-DTAB    ; MOVE POINTER TO 'NUMBER'.
899A  A03A                LDY     #LP-DTAB
899C  20459A              JSR     DMOVI

899F  A924                LDA     #'$'
89A1  2C6705              BIT     DMPTYP
89A4  3004 ^89AA          BMI     :DM020          ; STRING
89A6  A923                LDA     #'#'
89A8  5003 ^89AD          BVC     :DM030          ; I/O.

89AA  208294      :DM020  JSR     CHOT            ; PREFIX NAME FOR STRING, NUMERIC.

89AD  A002        :DM030  LDY     #2
89AF  20F189              JSR     PRTSFD          ; PRINT NAME.

89B2  208189              JSR     PRTEQS          ; SEPARATE NAME AND DATA WITH '='

89B5  2C6705              BIT     DMPTYP
89B8  301E ^89D8          BMI     :DM040          ; STRING.

89BA  C8                  INY                     ; NUMERIC OR I/O.
89BB  B1B8                LDA     (NUMBER),Y
89BD  5006 ^89C5          BVC     :DM032          ; I/O.
89BF  AA                  TAX                     ; NUMERIC.
89C0  C8                  INY
89C1  B1B8                LDA     (NUMBER),Y
89C3  7007 ^89CC          BVS     :DM035          ; (BRA).

89C5  4A          :DM032  LSR     A               ; IOCB = # * 16.
89C6  4A                  LSR     A
89C7  4A                  LSR     A
89C8  4A                  LSR     A
89C9  AA                  TAX
89CA  A900                LDA     #0              ; MSB = 0.

89CC  85B9        :DM035  STA     NUMBER+1        ; MSB.
89CE  86B8                STX     NUMBER          ; LSB.
89D0  A238                LDX     #NUMBER-DTAB
89D2  20149E              JSR     DECASC          ; PRINT VALUE.
89D5  4CE589              JMP     :DM050

89D8  A927        :DM040  LDA     #SQUOTE         ; DELIMIT STRING DATA WITH '.
89DA  208294              JSR     CHOT
89DD  20F189              JSR     PRTSFD          ; PRINT STRING DATA.
89E0  A927                LDA     #SQUOTE         ; CLOSING DELIMITER.
89E2  208294              JSR     CHOT

89E5  20989F      :DM050  JSR     NEWLIN

89E8  A23A        :DM080  LDX     #LP-DTAB        ; INCREMENT TO NEXT VARIABLE.
89EA  20AA9A              JSR     SNXTI
89ED  4C8989              JMP     :DM010

89F0  60          :DM090  RTS


89F1                      PROC
89F1  B1B8        PRTSFD  LDA     (NUMBER),Y      ; GET NAME/DATA LENGTH.
89F3  AA                  TAX
89F4  F012 ^8A08          BEQ     :PF090          ; DONE.

89F6  C8          :PF010  INY
89F7  D002 ^89FB          BNE     :PF020

89F9  E6B9                INC     NUMBER+1        ; INDEX WRAPAROUND -- BUMP POINTER.

89FB  B1B8        :PF020  LDA     (NUMBER),Y      ; GET CHARACTER.
89FD  208294              JSR     CHOT
8A00  CA                  DEX                     ; DONE?
8A01  D0F3 ^89F6          BNE     :PF010          ; NO.

8A03  C8                  INY
8A04  D002 ^8A08          BNE     :PF090          ; YES.

8A06  E6B9                INC     NUMBER+1        ; INDEX WRAPAROUND -- BUMP POINTER

8A08  60          :PF090  RTS


8A09                      PROC
                  ;
                  ; XPALET -- COLORS COMMAND PROCESSOR
                  ;
8A09  F013 ^8A1E  XPALET  BEQ     :XP090          ; SYNTAX SCAN ONLY.

8A0B  A200                LDX     #0              ; SETUP TO SCAN COLOR NAME TABLE.

8A0D  204FA5      :XP010  JSR     PRNTCL          ; PRINT COLOR NAME FROM TABLE.
8A10  209D9F              JSR     SPACES
8A13  E8                  INX                     ; SKIP OVER 'SB' ...
8A14  E8                  INX                     ; ... & COLOR VALUF.
8A15  E071                CPX     #PCTUP-PCTAB    ; END OF TABLE?
8A17  D0F4 ^8A0D          BNE     :XP010          ; NO -- CONTINUE.

8A19  20989F              JSR     NEWLIN
8A1C  A900                LDA     #0

8A1E  60          :XP090  RTS                     ; YES -- RETURN WITH CC SET.


                  ;
                  ; XCOLRS -- PS COMMAND PROCESSOR
                  ;
8A1F  F0FD ^8A1E  XCOLRS  BEQ     :XP090          ; SYNTAX SCAN ONLY.

8A21  20BB96              JSR     TSTMOD          ; GRAPHICS SPLIT SCREEN?
8A24  C904                CMP     #GRSS
8A26  D079 ^8AA1          BNE     :XC092          ; NO -- ERROR.

8A28  84AB                STY     XTEMP           ; SAVE Y REG.
8A2A  A927                LDA     #39             ; 'PENS: '.
8A2C  20FFB4              JSR     MESSOT
8A2F  A201                LDX     #1              ; SETUP TO EXAMINE COLOR ASSIGNS.

8A31  ECB905      :XC005  CPX     NCOLRS          ; END OF TABLE?
8A34  F002 ^8A38          BEQ     :XC010          ; NO.
8A36  B017 ^8A4F          BCS     :XC025          ; YES -- ALL DONE WITH PENS.

8A38  8A          :XC010  TXA                     ; GET PEN NUMBER.
8A39  4930                EOR     #'0'            ; CONVERT TO ASCII.
8A3B  208294              JSR     CHOT
8A3E  208189              JSR     PRTEQS          ; '='
8A41  ECBA05              CPX     NXTCLR          ; PEN ASSIGNED?
8A44  B003 ^8A49          BCS     :XC020          ; NO.

8A46  201AA5              JSR     PRCLNM          ; YES -- PRINT COLOR NAME.

8A49  209D9F      :XC020  JSR     SPACES
8A4C  E8                  INX                     ; NEXT PEN.
8A4D  D0E2 ^8A31          BNE     :XC005          ; (BRA).

8A4F  20989F      :XC025  JSR     NEWLIN
8A52  A928                LDA     #40             ; 'BACKGROUND: '.
8A54  20FFB4              JSR     MESSOT
8A57  A200                LDX     #0              ; BACKGROUND SLOT NUMBER.
8A59  201AA5              JSR     PRCLNM          ; PRINT COLOR NAME.

8A5C  A97F                LDA     #TAB
8A5E  208294              JSR     CHOT

8A61  A92A                LDA     #42             ; 'MODE: '
8A63  20FFB4              JSR     MESSOT
8A66  AD3705              LDA     GSMODE
8A69  85A9                STA     TEMP2+2
8A6B  A900                LDA     #0
8A6D  85AA                STA     TEMP2+3
8A6F  A229                LDX     #TEMP2+2-DTAB
8A71  20149E              JSR     DECASC          ; PRINT NODE NUMBER.
8A74  20989F              JSR     NEWLIN

8A77  A929                LDA     #41             ; 'TURTLE PEN: '.
8A79  20FFB4              JSR     MESSOT
8A7C  AD1305              LDA     PEN
8A7F  1004 ^8A85          BPL     :XC030          ; PEN DOWN.

8A81  A271                LDX     #PCTUP-PCTAB    ; 'UP'.
8A83  D002 ^8A87          BNE     :XC040          ; (BRA).

8A85  A275        :XC030  LDX     #PCTDN-PCTAB    ; 'DOWN'.

8A87  204FA5      :XC040  JSR     PRNTCL          ; PRINT 'UP' OR 'DOWN'.

8A8A  A92F                LDA     #'/'            ; '/'
8A8C  208294              JSR     CHOT
8A8F  AD1305              LDA     PEN             ; NOW PRINT PEN NUNBER.
8A92  290F                AND     #$0F
8A94  4930                EOR     #'0'            ; CONVERT TO ASCII.
8A96  208294              JSR     CHOT
8A99  20989F              JSR     NEWLIN


8A9C  A4AB                LDY     XTEMP
8A9E  A900                LDA     #0              ; SET CC FOR EXIT.

8AA0  60          :XC090  RTS

8AA1  A983        :XC092  LDA     #NRCERR         ; COMMAND ONLY VALID IN GRSS
8AA3  60                  RTS


8AA4                      PROC

                  ; XENVIR -- ES COMMAND, TURTLE ENVIRONMENT STATUS

8AA4  F077 ^8B1D  XENVIR  BEQ     :XE090          ; SYNTAX SCAN ONLY.

8AA6  20BB96              JSR     TSTMOD          ; GRAPHICS SPLIT SCREEN?
8AA9  C904                CMP     #GRSS
8AAB  D071 ^8B1E          BNE     :XE092          ; NO -- ERROR.

8AAD  84AB                STY     XTEMP           ; SAVE Y REGISTER.

8AAF  A92B                LDA     #43             ; 'EDGE:'.
8AB1  20FFB4              JSR     MESSOT
8AB4  A200                LDX     #0

8AB6  86AC        :XE010  STX     XTEMP+1

8AB8  BD0D80      :XE020  LDA     EDGTAB,X        ; SCAN TO NAME DELIMITER.
8ABB  E8                  INX
8ABC  C980                CMP     #SB
8ABE  D0F8 ^8AB8          BNE     :XE020

8AC0  BD0D80              LDA     EDGTAB,X        ; SEE IF THIS IS THE RULE IN EFFECT.
8AC3  E8                  INX
8AC4  CD5E05              CMP     EDGRUL
8AC7  D0ED ^8AB6          BNE     :XE010          ; NO -- SCAN TO NEXT NAME.

8AC9  A6AC                LDX     XTEMP+1         ; YES -- BACKUP TO NAME TEXT.

8ACB  BD0D80      :XE030  LDA     EDGTAB,X        ; GET A CHARACTER.
8ACE  3006 ^8AD6          BMI     :XE040          ; DELIMITER.

8AD0  208294              JSR     CHOT            ; OUTPUT CHAR.
8AD3  E8                  INX
8AD4  D0F5 ^8ACB          BNE     :XE030          ; (BRA).

8AD6  A97F        :XE040  LDA     #TAB
8AD8  208294              JSR     CHOT
8ADB  A92C                LDA     #44             ; 'SPEED: '.
8ADD  20FFB4              JSR     MESSOT
8AE0  AD5D05              LDA     SPEED
8AE3  85A7                STA     TEMP2
8AE5  A900                LDA     #0
8AE7  85A8                STA     TEMP2+1
8AE9  A227                LDX     #TEMP2-DTAB
8AEB  20149E              JSR     DECASC
8AEE  20989F              JSR     NEWLIN

8AF1  A92D                LDA     #45             ; 'WALLS: '.
8AF3  20FFB4              JSR     MESSOT
8AF6  18                  CLC
8AF7  A001                LDY     #1

8AF9  6ECE05      :XE050  ROR     WALLS+1
8AFC  6ECD05              ROR     WALLS
8AFF  900F ^8B10          BCC     :XE060          ; NOT A WALL SELECT.

8B01  84A7                STY     TEMP2           ; A WALL SELECT, PRINT POSITION #.
8B03  A900                LDA     #0
8B05  85A8                STA     TEMP2+1
8B07  A227                LDX     #TEMP2-DTAB
8B09  20149E              JSR     DECASC
8B0C  20A29F              JSR     SPACE
8B0F  38                  SEC

8B10  C8          :XE060  INY
8B11  98                  TYA
8B12  4912                EOR     #17+1           ; COMPARE WITHOUT ALTERING THE CARRY.
8B14  D0E3 ^8AF9          BNE     :XE050

8B16  20989F              JSR     NEWLIN
8B19  A4AB                LDY     XTEMP
8B1B  A900                LDA     #0

8B1D  60          :XE090  RTS

8B1E  A983        :XE092  LDA     #NRCERR         ; COMMAND VALID ONLY IN GRSS.
8B20  60                  RTS

8B21                      PROC
8B21  A20A        XTV     LDX     #ONOFFX         ; CHECK FOR 'ON' OR 'OFF'.
8B23  20AB7C              JSR     SBCMAT
8B26  D014 ^8B3C          BNE     :XT090          ; ERROR.

8B28  A592                LDA     EXEC            ; EXECUTE MODE?
8B2A  F010 ^8B3C          BEQ     :XT090          ; NO.

8B2C  8A                  TXA                     ; ON OR OFF?
8B2D  F00E ^8B3D          BEQ     :XT100          ; OFF.

8B2F  ADE005              LDA     DMASAV          ; ON -- TV OFF NOW?
8B32  F008 ^8B3C          BEQ     :XT090          ; NO.

8B34  8D2F02              STA     DMACT           ; YES -- RESTORE PRIOR STATE
8B37  A900                LDA     #0
8B39  8DE005              STA     DMASAV

8B3C  60          :XT090  RTS

8B3D  AD2F02      :XT100  LDA     DMACT           ; OFF -- IS TV ON NOW?
8B40  F0FA ^8B3C          BEQ     :XT090          ; NO.

8B42  8DE005              STA     DMASAV          ; YES -- SAVE STATE.
8B45  A900                LDA     #0              ; DMA OFF.
8B47  8D2F02              STA     DMACT
8B4A  60                  RTS

8B4B                      PROC
                  ;
                  ; COMPUTE COMMAND PROCESSOR
                  ;
8B4B  206E81      XCMPUT  JSR     ATOM            ; CHECK FOR TARGET VARIABLE.
8B4E  D06A ^8BBA          BNE     :XC900          ; INVALID ATOM.

8B50  C904                CMP     #NVAR
8B52  F00B ^8B5F          BEQ     :XC100          ; NUMERIC ASSIGNMENT.

8B54  C980                CMP     #BPTR           ; BYTE POINTER?
8B56  F007 ^8B5F          BEQ     :XC100          ; YES -- SAME AS NUMERIC VARIABLE.

8B58  2918                AND     #SVAR+USVAR     ; STRING ASSIGNMENT?
8B5A  D036 ^8B92          BNE     :XC200          ; YES.

8B5C  A902        :XC092  LDA     #IMPERR         ; NO -- ERROR.
8B5E  60                  RTS

                  ; ARITHMETIC ASSIGNMENT

8B5F  85AB        :XC100  STA     XTEMP           ; SAVE TARGET TYPE.

8B61  20009F              JSR     CHKEQS          ; CHECK FOR ASSIGNMENT OPERATOR NEXT.
8B64  D0F6 ^8B5C          BNE     :XC092          ; ASSIGNMENT SYNTAX ERROR.

8B66  A5B6                LDA     POINT           ; SAVE TARGET ADDRESS.
8B68  48                  PHA
8B69  A5B7                LDA     POINT+1
8B6B  48                  PHA

8B6C  C8                  INY                     ; PREPARE TO EVALUATE EXPRESSION.
8B6D  20D49F              JSR     EXP             ; EVALUATE EXPRESSION.

8B70  68                  PLA                     ; RESTORE TARGET ADDRESS.
8B71  85B7                STA     POINT+1
8B73  68                  PLA
8B74  85B6                STA     POINT

8B76  A592                LDA     EXEC            ; EXECUTE MODE?
8B78  F040 ^8BBA          BEQ     :XC900          ; NO.

8B7A  84AC                STY     XTEMP+1         ; SAVE LINE INDEX.
8B7C  A000                LDY     #0              ; STORE RESULT TO TARGET.
8B7E  A593                LDA     EXPSTK
8B80  91B6                STA     (POINT),Y
8B82  A5AB                LDA     XTEMP           ; SEE IF TARGET IS POINTER TO BYTE.
8B84  C980                CMP     #BPTR
8B86  F005 ^8B8D          BEQ     :XC120          ; YES -- ALL DONE.

8B88  C8                  INY
8B89  A594                LDA     EXPSTK+1
8B8B  91B6                STA     (POINT),Y

8B8D  A4AC        :XC120  LDY     XTEMP+1         ; RESTORE LINE INDEX.
8B8F  A900                LDA     #0              ; COMPUTE WAS A SUCCESS.
8B91  60                  RTS


                  ; STRING ASSIGNMENT

8B92  20009F      :XC200  JSR     CHKEQS          ; ASSIGNMENT OPERATOR?
8B95  D0C5 ^8B5C          BNE     :XC092          ; NO -- ERROR.

8B97  20C18B              JSR     SAVIT2          ; SAVE 'NP' TO 'MP' TEMPORARILY

8B9A  C8                  INY                     ; SKIP OVER '='.
8B9B  20A7A0              JSR     TEXP            ; EVALUATE TEXT EXPRESSION.

8B9E  A592                LDA     EXEC            ; EXECUTE MODE?
8BA0  F018 ^8BBA          BEQ     :XC900          ; NO -- DON'T DO ASSIGNMENT.

8BA2  84AC                STY     XTEMP+1
8BA4  20058C              JSR     RESIT2          ; RESTORE 'NP' FROM 'MP'.

                  ; *** EXTERNAL ENTRY POINT FROM 'XACCPT' ***

8BA7  A242        XCM300  LDX     #DP-DTAB        ; MOVE 'TELN' TO 'DP'.
8BA9  A00C                LDY     #TELN-DTAB
8BAB  203B9A              JSR     PMOVE

8BAE  A980                LDA     #ATRSTR         ; 'STRING' ATTRIBUTE.
8BB0  8D6605              STA     ATRTYP
8BB3  200599              JSR     SINSRT          ; INSERT STRING.
8BB6  08                  PHP
8BB7  A4AC                LDY     XTEMP+1
8BB9  28                  PLP

8BBA  60          :XC900  RTS                     ; RETURN WITH CC SET.

8BBB                      PROC
8BBB  A5AB        SAVIT   LDA     XTEMP           ; STRING TARGET?
8BBD  2918                AND     #SVAR+USVAR
8BBF  F036 ^8BF7          BEQ     :SV090          ; NO.

8BC1  A592        SAVIT2  LDA     EXEC            ; EXECUTE MODE?
8BC3  F032 ^8BF7          BEQ     :SV090          ; NO.

8BC5  98                  TYA                     ; SAVE Y REGISTER.
8BC6  48                  PHA

8BC7  A97B                LDA     # LOW NAMBUF    ; NAME SAVE AREA.
8BC9  85C6                STA     MP
8BCB  A9BE                LDA     # HIGH NAMBUF
8BCD  85C7                STA     MP+1
8BCF  A002                LDY     #2              ; TARGET STRING START INDEX.
8BD1  8C4205              STY     NAMLNG

8BD4  A4C0                LDY     NP+2            ; SOURCE STRING START INDEX.
8BD6  C4C1                CPY     NP+3            ; NULL SOURCE?
8BD8  F01E ^8BF8          BEQ     :SV100          ; YES -- ERROR.

8BDA  C4C1        :SV010  CPY     NP+3            ; END OF STRING?
8BDC  F017 ^8BF5          BEQ     :SV080          ; YES.

8BDE  B1BE                LDA     (NP),Y          ; NO -- GET A CHAR.
8BE0  C8                  INY
8BE1  84A1                STY     TEMP
8BE3  20B69E              JSR     CKEOA           ; END OF ATOM (STRING NAME)?
8BE6  F010 ^8BF8          BEQ     :SV100          ; YES -- ERROR.

8BE8  AC4205              LDY     NAMLNG          ; STORE A CHAR.
8BEB  91C6                STA     (MP),Y
8BED  C8                  INY
8BEE  8C4205              STY     NAMLNG

8BF1  A4A1                LDY     TEMP
8BF3  D0E5 ^8BDA          BNE     :SV010          ; TRY AGAIN (BRA).

8BF5  68          :SV080  PLA                     ; RESTORE Y REGISTER.
8BF6  A8                  TAY

8BF7  60          :SV090  RTS

8BF8  68          :SV100  PLA                     ; RESTORE Y REGISTER.
8BF9  A8                  TAY
8BFA  A982                LDA     #ATMERR+NS      ; INVALID STRING NAME.

8BFC  4C3A7A      :SV190  JMP     PSTOP           ; ABORT COMMAND.

8BFF                      PROC
8BFF  A5AB        RESIT   LDA     XTEMP           ; STRING TARGET?
8C01  2918                AND     #SVAR+USVAR
8C03  F011 ^8C16          BEQ     :RS090          ; NO.

8C05  A97B        RESIT2  LDA     # LOW NAMBUF
8C07  85BE                STA     NP
8C09  A9BE                LDA     # HIGH NAMBUF
8C0B  85BF                STA     NP+1
8C0D  A902                LDA     #2
8C0F  85C0                STA     NP+2
8C11  AD4205              LDA     NAMLNG
8C14  85C1                STA     NP+3

8C16  60          :RS090  RTS


8C17                      PROC
                  ;
                  ; XGRAPH -- GRAPHICS COMMAND PROCESSOR
                  ;
8C17  A592        XGRAPH  LDA     EXEC            ; EXECUTE MODE?
8C19  F00F ^8C2A          BEQ     :XG020          ; NO.

8C1B  AD1405              LDA     GRFLAG          ; YES -- GRAPHICS SCREEN OPEN?

8C1E  D00A ^8C2A          BNE     :XG020          ; YES.

8C20  2060AF              JSR     GPINIT          ; INITIALIZE GRAPHICS PARAMETERS.
8C23  84AB                STY     XTEMP
8C25  201095              JSR     GSOPEN          ; OPEN GRAPHICS SCREEN.
8C28  A4AB                LDY     XTEMP

8C2A  20398C      :XG020  JSR     GCOMND          ; PROCESS ONE GRAPHICS SUB-COMMAND.

8C2D  20139F              JSR     SLB             ; SEE IF MULTIPLES.
8C30  C8                  INY
8C31  C93B                CMP     #';'
8C33  F0E2 ^8C17          BEQ     XGRAPH          ; YES.

8C35  88                  DEY                     ; NO -- ALL DONE.
8C36  A900                LDA     #0              ; CLEAR CC FOR NORMAL EXIT.
8C38  60                  RTS                     ; RETURN WITH CC SET.


8C39                      PROC
                  ; 'GCOMND' PROCESS ONE GRAPHICS SUB-COMMAND OR NESTED GROUP.

8C39  20139F      GCOMND  JSR     SLB             ; SKIP LEADING BLANKS.
8C3C  C928                CMP     #'('             ; CHECK FOR GROUPING WITH '(' & ')'
8C3E  F022 ^8C62          BEQ     :GC100

8C40  206E81              JSR     ATOM            ; CHECK ATOM TYPE.
8C43  D01A ^8C5F          BNE     :GC090          ; ATOM ERROR.

8C45  2986                AND     #NUM+NVAR+BPTR  ; IF NUMERIC, THEN TREAT AS ITERATION COUNT.
8C47  D02A ^8C73          BNE     :GC200          ; YEP.

8C49  A204                LDX     #GTABX          ; NO -- ASSUME ITS A SUB-COMMAND.
8C4B  20AB7C              JSR     SBCMAT
8C4E  D00F ^8C5F          BNE     :GC090          ; NO -- ERROR.

8C50  BDAA80              LDA     SBDTAB,X        ; SETUP ADDRESS OF G-ROUTINE.
8C53  8D0B05              STA     GJUMP+1
8C56  BDAB80              LDA     SBDTAB+1,X
8C59  8D0C05              STA     GJUMP+2

8C5C  4C0A05              JMP     GJUMP           ; GO TO G-ROUTINE & RETURN.

8C5F  4C3A7A      :GC090  JMP     PSTOP           ; FATAL ERROR -- STOP EXECUTION.

                  ; THIS SECTION HANDLES NESTED GROUPS.

8C62  C8          :GC100  INY                     ; SKIP OVER '('.
8C63  20178C              JSR     XGRAPH          ; PROCESS ONE SUB-COMMAND OR NESTED GROUP.

8C66  20139F              JSR     SLB
8C69  C8                  INY
8C6A  C929                CMP     #')'            ; MATCHING PAREN?
8C6C  F04A ^8CB8          BEQ     :GC390          ; YES -- O.K.

8C6E  88                  DEY                     ; NO -- ERROR.
8C6F  A902                LDA     #NSTERR
8C71  D0EC ^8C5F          BNE     :GC090          ; (BRA).

                  ; THIS SECTION HANDLES ITERATIONS

                  ;
                  ; *** EXTERNAL ENTRY POINT ***
                  ;
8C73              GITER

8C73  A592        :GC200  LDA     EXEC            ; EXECUTE MODE?
8C75  F034 ^8CAB          BEQ     :GC300          ; NO -- SYNTAX SCAN ONLY.

8C77  A5B8                LDA     NUMBER          ; SEE IF ZERO ITERATIONS.
8C79  05B9                ORA     NUMBER+1
8C7B  F02E ^8CAB          BEQ     :GC300          ; YES -- SCAN OVER ITERATION BODY.

8C7D  A5DE                LDA     LS              ; NO -- SAVE COUNTER ('LS') ...
8C7F  48                  PHA
8C80  A5DF                LDA     LS+1
8C82  48                  PHA
8C83  98                  TYA                     ; ... & LINE INDEX.
8C84  48                  PHA

8C85  A5B8                LDA     NUMBER          ; GET LOOP COUNT TO 'LS'.
8C87  85DE                STA     LS
8C89  A5B9                LDA     NUMBER+1
8C8B  85DF                STA     LS+1

8C8D  20398C      :GC220  JSR     GCOMND          ; PROCESS ONE COMMAND.

8C90  A25E                LDX     #LS-DTAB        ; DECREMENT ITERATION COUNT.
8C92  20129D              JSR     DDCRI
8C95  A5DE                LDA     LS              ; CHECK FOR RESULT = 0.
8C97  05DF                ORA     LS+1
8C99  F008 ^8CA3          BEQ     :GC240          ; DONE.

8C9B  207E9F              JSR     ABRTCK          ; CHECK FOR OPERATOR ABORT.
8C9E  68                  PLA                     ; NOT DONE -- RESTORE SCAN INDEX.
8C9F  48                  PHA
8CA0  A8                  TAY
8CA1  D0EA ^8C8D          BNE     :GC220          ; (BRA) EXECUTE BODY AGAIN.

8CA3  68          :GC240  PLA                     ; THROW AWAY STARTING INDEX.
8CA4  68                  PLA                     ; RESTORE 'LS'.
8CA5  85DF                STA     LS+1
8CA7  68                  PLA
8CA8  85DE                STA     LS
8CAA  60                  RTS

                  ; THIS SECTION SYNTAX SCANS THE BODY OF AN ITERATION.

8CAB  A592        :GC300  LDA     EXEC            ; SAVE CURRENT VALUE.
8CAD  48                  PHA
8CAE  A900                LDA     #0              ; SETUP FOR SCAN ONLY
8CB0  8592                STA     EXEC

8CB2  20398C              JSR     GCOMND          ; *** RECURSIVE CALL **

8CB5  68                  PLA                     ; RESTORE MODE.
8CB6  8592                STA     EXEC

8CB8  60          :GC390  RTS                     ; PETURN WITH CC SET.


8CB9                      PROC
                  ;
                  ; GREPT -- 'REPEAT' GRAPHICS SUBCOMMAND
                  ;
8CB9  206E81      GREPT   JSR     ATOM            ; REPEAT COUNT MUST FOLLOW.
8CBC  D009 ^8CC7          BNE     :GR090          ; ERROR.

8CBE  2986                AND     #NUM+NVAR+BPTR  ; NUMERIC DATA?
8CC0  F003 ^8CC5          BEQ     :GR088          ; NO -- ERROR.

8CC2  4C738C              JMP     GITER           ; YES -- PROCESS REPEAT LOGIC.

8CC5  A902        :GR088  LDA     #IMPERR

8CC7  4C3A7A      :GR090  JMP     PSTOP

8CCA                      PROC
                  ;
                  ; XSOUND -- SOUND COMMAND PROCESSOR
                  ;
8CCA  A208        XSOUND  LDX     #AUREGS*2       ; SETUP INDEX TO A OF REGS.

8CCC  20079F      :XS010  JSR     SKPSEP          ; SKIP SEPARATORS & GET CHAR.
8CCF  20F99E              JSR     CHKTRM          ; TERMINATOR?
8CD2  F052 ^8D26          BEQ     :XS080          ; YES -- ALL DONE.

8CD4  C928                CMP     #'('            ; LEFT PAREN?
8CD6  F04B ^8D23          BEQ     :XS050          ; YES -- START OF NOTE LIST.

8CD8  C929                CMP     #')'            ; RIGHT PAREN?
8CDA  F04A ^8D26          BEQ     :XS080          ; YES -- END OF NOTE LIST.

8CDC  C93D                CMP     #'='            ; EQUAL SIGN?
8CDE  F022 ^8D02          BEQ     :XS020          ; YES -- NO CHANGE FOR VOICE.

8CE0  C92B                CMP     #'+'            ; PLUS SIGN?
8CE2  F021 ^8D05          BEQ     :XS030          ; YES -- INCREMENT NOTE.

8CE4  C92D                CMP     #'-'            ; MINUS SIGN.
8CE6  F02C ^8D14          BEQ     :XS040          ; YES -- DECREMENT NOTE.

8CE8  20578D              JSR     GTNOTE          ; GET NUMERIC VALUE.
8CEB  D064 ^8D51          BNE     :XS090          ; ERROR.

8CED  A5B8                LDA     NUMBER          ; NOTE := NUM.

8CEF  85AB        :XS015  STA     XTEMP           ; SAVE NOTE #
8CF1  A592                LDA     EXEC            ; EXECUTE MODE?
8CF3  F007 ^8CFC          BEQ     :XS017          ; NO.

8CF5  A5AB                LDA     XTEMP           ; YES.
8CF7  0980                ORA     #$80            ; SET BIT FOR NOT A POINTER.
8CF9  9D1405              STA     AUDIOR-1,X

8CFC  CA          :XS017  DEX                     ; MORE OPERANDS ALLOWED?
8CFD  CA                  DEX
8CFE  D0CC ^8CCC          BNE     :XS010          ; YES.

8D00  F024 ^8D26          BEQ     :XS080          ; NO -- SEE IF DURATION (BRA).

8D02  C8          :XS020  INY
8D03  D0F7 ^8CFC          BNE     :XS017          ; (BRA).

8D05  C8          :XS030  INY
8D06  20578D              JSR     GTNOTE          ; GET INCREMENT VALUE.
8D09  D046 ^8D51          BNE     :XS090          ; ERROR.

8D0B  BD1405              LDA     AUDIOR-1,X      ; NOTE :=NOTE + NUM.
8D0E  18                  CLC
8D0F  65B8                ADC     NUMBER
8D11  4CEF8C              JMP     :XS015

8D14  C8          :XS040  INY

8D15  20578D              JSR     GTNOTE          ; GET DECREMENT VALUE.
8D18  D037 ^8D51          BNE     :XS090          ; ERROR.

8D1A  BD1405              LDA     AUDIOR-1,X      ; NOTE := NOTE - NUM.
8D1D  38                  SEC
8D1E  E5B8                SBC     NUMBER
8D20  4CEF8C              JMP     :XS015

8D23  C8          :XS050  INY                     ; SKIP OVER LEFT RAREN.
8D24  D0A6 ^8CCC          BNE     :XS010          ; (BRA).

8D26  A592        :XS080  LDA     EXEC            ; EXECUTE MODE?
8D28  F01A ^8D44          BEQ     :XS084          ; NO.

8D2A  E000                CPX     #0
8D2C  F00F ^8D3D          BEQ     :XS083

8D2E  A900        :XS082  LDA     #0              ; CLEAR UNSPECIFIED VOICES.
8D30  9D1405              STA     AUDIOR-1,X
8D33  9DFED1              STA     AUDF1-2,X       ; CLEAR SOUND REGISTERS.
8D36  9DFFD1              STA     AUDC1-2,X
8D39  CA                  DEX
8D3A  CA                  DEX
8D3B  D0F1 ^8D2E          BNE     :XS082

8D3D  84AB        :XS083  STY     XTEMP
8D3F  204FB4              JSR     TONES
8D42  A4AB                LDY     XTEMP

8D44  B180        :XS084  LDA     (INLN),Y        ; DURATION FOLLOWING?
8D46  C929                CMP     #')'
8D48  D004 ^8D4E          BNE     :XS088          ; NO.

8D4A  C8                  INY                     ; YES -- SKIP OVER LEFT PAREN.
8D4B  4C548F              JMP     XWAIT           ; PROCESS DURATION AS A PAUSE.

8D4E  A900        :XS088  LDA     #0              ; RETURN WITH CC SET.
8D50  60                  RTS

8D51  20B49F      :XS090  JSR     AUDCLR          ; CLEAR ALL SOUND REGS.

8D54  A902        XIN080  LDA     #IMPERR

8D56  60          XIN090  RTS                     ; RETURN WITH CC SET.


8D57                      PROC
8D57  86AB        GTNOTE  STX     XTEMP           ; SAVE X REGISTER.
8D59  206E81              JSR     ATOM            ; GET OPERAND.
8D5C  D008 ^8D66          BNE     :GN090          ; ERROR.

8D5E  2986                AND     #NUM+NVAR+BPTR
8D60  F005 ^8D67          BEQ     :GN092          ; ERROR.

8D62  A6AB                LDX     XTEMP           ; RESTORE X REGISTER.
8D64  A900                LDA     #0

8D66  60          :GN090  RTS

8D67  A902        :GN092  LDA     #IMPERR
8D69  60                  RTS


8D6A                      PROC
                  ;
                  ; XIN -- READ COMMAND PROCESSOR
                  ;
8D6A  A904        XIN     LDA     #OREAD          ; READ DIRECTION.
8D6C  20FD97              JSR     SCNDEV          ; CONVERT DEVICE SPEC TO IOCB INDEX
8D6F  D0E5 ^8D56          BNE     XIN090          ; ERROR.

8D71  86AD                STX     XTEMP+2         ; SAVE IOCB INDEX.
8D73  20079F              JSR     SKPSEP          ; SKIP OVER SEPARATOR.
8D76  206E81              JSR     ATOM            ; FIND TYPE OF VARIABLE.
8D79  D0DB ^8D56          BNE     XIN090          ; ERROR.

8D7B  85AB                STA     XTEMP           ; SAVE ATOM TYPE.
8D7D  299D                AND     #SVAR+USVAR+NVAR+NULL+BPTR ; VALID TYPE?
8D7F  F0D3 ^8D54          BEQ     XIN080          ; NO.

8D81  A592                LDA     EXEC            ; EXECUTE MODE?
8D83  F0D1 ^8D56          BEQ     XIN090          ; NO.

8D85  84AC                STY     XTEMP+1         ; SAVE LINE INDEX.
8D87  A6AD                LDX     XTEMP+2         ; GET IOCB INDEX.
8D89  A000                LDY     #0              ; INIT INDEX TO ACCEPT BUFFER.
8D8B  848E                STY     TELN+2

8D8D  AD2005              LDA     OPNBUF          ; SEE IF READING FROM TEXT SCREEN.
8D90  C945                CMP     #'E'
8D92  D004 ^8D98          BNE     :XI030          ; NO.

8D94  98                  TYA                     ; YES -- ENABLE CURSOR CY = 0).
8D95  20A79F              JSR     CRSNOP          ; MAKE IT APPEAR.

8D98  205397      :XI030  JSR     DIN             ; GET A CHARACTER FROM DEVICE.
8D9B  C99B                CMP     #EOL            ; END OF LINE?
8D9D  F00E ^8DAD          BEQ     :XI040          ; YES -- DONE.

8D9F  918C                STA     (TELN),Y
8DA1  C8                  INY
8DA2  C0FE                CPY     #TEXLNG         ; BUFFER FULL?
8DA4  D0F2 ^8D98          BNE     :XI030          ; NO.

8DA6  205397      :XI035  JSR     DIN             ; YES -- FLUSH TO EOL.
8DA9  C99B                CMP     #EOL
8DAB  D0F9 ^8DA6          BNE     :XI035

8DAD  848F        :XI040  STY     TELN+3          ; SAVE STRING END INDEX.
8DAF  AD2005              LDA     OPNBUF          ; READING FROM TEXT SCREEN?
8DB2  C945                CMP     #'E'
8DB4  D003 ^8DB9          BNE     :XI045          ; NO.

8DB6  20A79F              JSR     CRSNOP          ; DISABLE CURSOR AGAIN (A = $45).

8DB9  A901        :XI045  LDA     #1              ; SET ACCEPT LITERAL.
8DBB  8D4605              STA     AXFLAG
8DBE  20BB8B              JSR     SAVIT           ; SAVE NAME IF STRING TARGET.
8DC1  4CC785              JMP     XAC024          ; GO TO ACCEPT CODE TO FINISH PROCESSING.

8DC4                      PROC
                  ;
                  ; XOUT -- WRITE COMMAND PROCESSOR
                  ;
8DC4  A908        XOUT    LDA     #OWRIT          ; WRITE DIRECTION.
8DC6  20FD97              JSR     SCNDEV          ; CONVERT I/O SPEC TO DEVICE INDEX.
8DC9  D02B ^8DF6          BNE     :XO090          ; ERROR.

8DCB  86AB                STX     XTEMP           ; SAVE IOCB INDEX.
8DCD  B180                LDA     (INLN),Y
8DCF  20F99E              JSR     CHKTRM          ; TERMINATOR FOLLOWING DEVICE SPEC?
8DD2  F001 ^8DD5          BEQ     :XO005          ; YES -- DON'T ADVANCE INDEX.

8DD4  C8                  INY                     ; NO -- SKIP OVER SINGLE SEPARATOR.

8DD5  20A7A0      :XO005  JSR     TEXP            ; REST OF STATEMENT IS A TEXT EXPRESSION.

                  ; *S*   LDA     EXEC            ; EXECUTE MODE?

8DD8  F01C ^8DF6          BEQ     :XO090          ; NO.

8DDA  84AC                STY     XTEMP+1         ; SAVE LINE INDEX.

8DDC  A6AB                LDX     XTEMP           ; GET IOCB INDEX.
8DDE  A48E                LDY     TELN+2          ; START OF TEXT EXPRESSION EVALUATION.

8DE0  C48F        :XO010  CPY     TELN+3          ; DONE?
8DE2  F009 ^8DED          BEQ     :XO020          ; YES.

8DE4  B900BC              LDA     TEXBUF,Y        ; NO -- PUT CHAR TO DEVICE.
8DE7  205897              JSR     DOUT
8DEA  C8                  INY
8DEB  D0F3 ^8DE0          BNE     :XO010          ; (BRA).

8DED  A99B        :XO020  LDA     #EOL            ; TERMINATE RECORD.
8DEF  205897              JSR     DOUT

8DF2  A4AC                LDY     XTEMP+1
8DF4  A900                LDA     #0              ; SET CC FOR NORMAL EXIT.

8DF6  60          :XO090  RTS                     ; RETURN WITH CC SET.


8DF7                      PROC
                  ;
                  ; XDONE -- CLOSE COMMAND PROCESSOR
                  ;
8DF7  A900        XDONE   LDA     #0              ; INVALID OPEN CODE MEANS CLOSE.
8DF9  20FD97              JSR     SCNDEV          ; CONVERT DEVICE SPEC TO ICCB INDEX.
8DFC  D009 ^8E07          BNE     :XD090          ; ERROR.

8DFE  A592                LDA     EXEC            ; EXECUTE MODE?
8E00  F005 ^8E07          BEQ     :XD090          ; NO.

8E02  203F97              JSR     DCLOSE          ; YES -- CLOSE IOCB & DEVICE.

8E05  A900                LDA     #0              ; SET CC FOR NORMAL EXIT.

8E07  60          :XD090  RTS                     ; RETURN WITH CC SET.


8E08                      PROC
                  ;
                  ; XSSAV -- SAVE SCREEN COMMAND PROCESSOR.
                  ;
8E08  20C297      XSSAV   JSR     SFNAME          ; EXTRACT DEVICE/FILENAME.
8E0B  D050 ^8E5D          BNE     :XS090          ; ERROR.

8E0D  20079F              JSR     SKPSEP          ; SKIP SEPARATOR(S).

8E10  A592                LDA     EXEC            ; EXECUTE MODE?
8E12  F049 ^8E5D          BEQ     :XS090          ; NO.

8E14  A230                LDX     #IOCB3          ; YES -- OPEN DEVICE FOR OUTPUT.
8E16  A908                LDA     #OWRIT
8E18  20F496              JSR     DOPEN

8E1B  A90B                LDA     #PUTC           ; SETUP IOCB FOR PUT CHARACTER.
8E1D  9D4203              STA     ICCOM,X

8E20  A230                LDX     #IOCB3
8E22  AD1405              LDA     GRFLAG          ; GRAPHICS SCREEN FLAG.
8E25  205897              JSR     DOUT
8E28  AD3705              LDA     GSMODE          ; SAVE SCREEN MODE.
8E2B  205897              JSR     DOUT
8E2E  AD5205              LDA     SPLTSC          ; FULL/SPLIT FLAG.
8E31  205897              JSR     DOUT
8E34  AD5105              LDA     LETTRSZ         ; LETTER SIZE.
8E37  205897              JSR     DOUT

8E3A  A559                LDA     SAVMSC+1        ; SETUP POINTER TO BOTTOM OF SCREEN.
8E3C  85F7                STA     ADRESS+1
8E3E  A900                LDA     #0
8E40  85F6                STA     ADRESS
8E42  84AB                STY     XTEMP
8E44  A458                LDY     SAVMSC

8E46  B1F6        :XS010  LDA     (ADRESS),Y      ; GET DATA BYTE.
8E48  205897              JSR     DOUT            ; OUTPUT IT.
8E4B  C8                  INY
8E4C  D0F8 ^8E46          BNE     :XS010

8E4E  E6F7                INC     ADRESS+1
8E50  A5F7                LDA     ADRESS+1
8E52  C56A                CMP     RAMTOP          ; DONE?
8E54  D0F0 ^8E46          BNE     :XS010          ; NO.

8E56  A4AB                LDY     XTEMP
8E58  203F97              JSR     DCLOSE

8E5B  A900                LDA     #0              ; SET CC FOR NORMAL EXIT.

8E5D  60          :XS090  RTS                     ; RETURN WITH CC SET.

8E5E                      PROC
                  ;
                  ; XSLOAD -- LOAD SCREEN COMMAND PROCESSOR.
                  ;
8E5E  20C297      XSLOD   JSR     SFNAME          ; EXTRACT DEVICE/FILENAME.
8E61  D05F ^8EC2          BNE     :XS090          ; ERROR.

8E63  A592                LDA     EXEC            ; EXECUTE MODE?
8E65  F05B ^8EC2          BEQ     :XS090          ; NO.

8E67  A230                LDX     #IOCB3          ; YES -- OPEN DEVICE FOR INPUT.
8E69  A904                LDA     #OREAD
8E6B  20F496              JSR     DOPEN

8E6E  84AB                STY     XTEMP
8E70  A907                LDA     #GETC           ; SETUP I OCB FOR GET CHARACTER
8E72  9D4203              STA     ICCOM,X
8E75  A230                LDX     #IOCB3
8E77  205397              JSR     DIN             ; GET GRAPHICS FLAG.
8E7A  8D1405              STA     GRFLAG
8E7D  205397              JSR     DIN             ; GET SCREEN MODE.
8E80  8D3705              STA     GSMODE
8E83  205397              JSR     DIN             ; GET FULL/SPLIT FLAG.
8E86  8D5205              STA     SPLTSC
8E89  205397              JSR     DIN             ; GET LETTER SIZE.
8E8C  8D5105              STA     LETTRSZ
8E8F  20BB96              JSR     TSTMOD          ; SEE IF TEXT/SMALL LETTERS.
8E92  C901                CMP     #TXSL
8E94  D006 ^8E9C          BNE     :XS005          ; NO.

8E96  20F494              JSR     TXOPEN          ; YES.
8E99  4C9F8E              JMP     :XS007

8E9C  201095      :XS005  JSR     GSOPEN          ; OPEN SCREEN.

8E9F  A559        :XS007  LDA     SAVMSC+1        ; SETUP POINTER TO BOTTOM OF SCREEN
8EA1  85F7                STA     ADRESS+1
8EA3  A900                LDA     #0
8EA5  85F6                STA     ADRESS
8EA7  A230                LDX     #IOCB3
8EA9  A458                LDY     SAVMSC

8EAB  205397      :XS010  JSR     DIN
8EAE  91F6                STA     (ADRESS),Y
8EB0  C8                  INY
8EB1  D0F8 ^8EAB          BNE     :XS010

8EB3  E6F7                INC     ADRESS+1
8EB5  A5F7                LDA     ADRESS+1
8EB7  C56A                CMP     RAMTOP          ; DONE?
8EB9  D0F0 ^8EAB          BNE     :XS010          ; NO.

8EBB  A4AB                LDY     XTEMP
8EBD  203F97              JSR     DCLOSE

8EC0  A900                LDA     #0
8EC2  60          :XS090  RTS

8EC3                      PROC
                  ;
                  ; XDIR -- DISK DIRECTORY COMMAND PROCESSOR
                  ;
8EC3  20D49F      XDIR    JSR     EXP             ; GET DRIVE NUMBER.

8EC6  A592                LDA     EXEC            ; EXECUTE MODE?
8EC8  F034 ^8EFE          BEQ     :XD090          ; NO -- SYNTAX SCAN ONLY.

8ECA  A207                LDX     #:DTLNG         ; MOVE OPEN TEMPLATE ...

8ECC  BDFE8E      :XD005  LDA     :DIRTB-1,X      ; ... TO OPEN BUFFER.
8ECF  9D1F05              STA     OPNBUF-1,X
8ED2  CA                  DEX
8ED3  D0F7 ^8ECC          BNE     :XD005

8ED5  A593                LDA     EXPSTK          ; INSERT DRIVE A.
8ED7  4930                EOR     #'0'
8ED9  8D2105              STA     OPNBUF+1

8EDC  A230                LDX     #IOCB3
8EDE  A906                LDA     #OREAD+2        ; OPEN FOR DIRECTORY READ.
8EE0  20F496              JSR     DOPEN

8EE3  A230        :XD010  LDX     #IOCB3          ; GET A BYTE.
8EE5  205397              JSR     DIN

8EE8  A6E4                LDX     IOSTAT          ; CHECK FOR END-OF-FILE.
8EEA  E088                CPX     #$88
8EEC  F006 ^8EF4          BEQ     :XD020          ; EOF -- ALL DONE.

8EEE  208294              JSR     CHOT            ; WRITE TO SCREEN.
8EF1  4CE38E              JMP     :XD010

8EF4  A230        :XD020  LDX     #IOCB3          ; CLOSE THE FILE.
8EF6  203F97              JSR     DCLOSE
8EF9  20989F              JSR     NEWLIN

8EFC  A900                LDA     #0              ; SET CC FOR EXIT.
8EFE  60          :XD090  RTS

8EFF  44203A2A2E  :DIRTB  DB      'D :*.*',EOL    ; DIRECTORY OPEN TEMPLATE.
      = 0007      :DTLNG  = *-:DIRTB


8F06                      PROC
                  ;
                  ; XCOMM -- COMMAND TABLE LISTER
                  ;
8F06  F014 ^8F1C  XCOMM   BEQ     :XC090          ; SYNTAX SCAN ONLY.

8F08  AD0005              LDA     USRTAB          ; FIRST LIST USER SUPPLIED TABLE.
8F0B  AE0105              LDX     USRTAB+1

8F0E  F003 ^8F13          BEQ     :XC010          ; NO TABLE.

8F10  201D8F              JSR     PRINTC

8F13  A901        :XC010  LDA     # LOW CTAB      ; NOW LIST BUILT-IN TABLE.
8F15  A27D                LDX     # HIGH CTAB
8F17  201D8F              JSR     PRINTC

8F1A  A900                LDA     #0

8F1C  60          :XC090  RTS                     ; RETURN WITH CC SET.

8F1D  8590        PRINTC  STA     TABADR          ; SETUP POINTER TO BEGIN OF TABLE.
8F1F  8691                STX     TABADR+1
8F21  84AB                STY     XTEMP           ; SAVE Y REG.

8F23  A905        :PC003  LDA     #5              ; 5 NAMES PER LINE.
8F25  85AC                STA     XTEMP+1

8F27  A000        :PC005  LDY     #0              ; START NAME SCAN.

8F29  B190        :PC010  LDA     (TABADR),Y      ; GET CHARACTER.
8F2B  F021 ^8F4E          BEQ     :PC080          ; END OF TABLE.

8F2D  3006 ^8F35          BMI     :PC020          ; END OF NAME.

8F2F  208294              JSR     CHOT            ; OUTPUT CHARACTER.
8F32  C8                  INY
8F33  D0F4 ^8F29          BNE     :PC010          ; (BRA).

8F35  209D9F      :PC020  JSR     SPACES
8F38  C8                  INY                     ; SKIP OVER PARAMETERS.
8F39  C8                  INY
8F3A  98                  TYA                     ; ADD Y REG TO TABADR.
8F3B  18                  CLC
8F3C  6590                ADC     TABADR
8F3E  8590                STA     TABADR
8F40  9002 ^8F44          BCC     :PC030

8F42  E691                INC     TABADR+1

8F44  C6AC        :PC030  DEC     XTEMP+1         ; LINE FULL (5 NAMES)?
8F46  D0DF ^8F27          BNE     :PC005

8F48  20989F              JSR     NEWLIN          ; YES.
8F4B  4C238F              JMP     :PC003

8F4E  20989F      :PC080  JSR     NEWLIN
8F51  A4AB                LDY     XTEMP
8F53  60                  RTS


8F54                      PROC
                  ;
                  ; XWAIT -- PAUSE COMMAND PROCESSOR
                  ;
8F54  20D49F      XWAIT   JSR     EXP             ; THERE MUST BE AN EXPRESSION FOLLOWING.

8F57  A592                LDA     EXEC            ; EXECUTE MODE?
8F59  F01B ^8F76          BEQ     :XW090          ; NO -- ALL DONE.

8F5B  A213                LDX     #EXPSTK-DTAB    ; YES -- WORK WITH COUNT.
8F5D  84AB                STY     XTEMP           ; SAVE LINE INDEX.

8F5F  A4AB        :XW010  LDY     XTEMP           ; RESTORE INDEX.
8F61  A593                LDA     EXPSTK          ; ALL DONE?
8F63  0594                ORA     EXPSTK+1
8F65  F00F ^8F76          BEQ     :XW090          ; YES.

8F67  A414                LDY     RTCLOK+2        ; NO -- WAIT FOR ...

8F69  207E9F      :XW020  JSR     ABRTCK          ; ... OPERATOR ABORT ...
8F6C  C414                CPY     RTCLOK+2
8F6E  F0F9 ^8F69          BEQ     :XW020          ; ... OR CLOCK TO CHANGE.

8F70  20129D              JSR     DDCRI           ; DECREMENT COUNT.
8F73  4C5F8F              JMP     :XW010

8F76  60          :XW090  RTS

8F77                      PROC
                  ;
                  ; XSPEED -- SPEED CONTROL COMMAND PROCESSOR
                  ;
8F77  20D49F      XSPEED  JSR     EXP             ; THERE MUST BE AN EXPRESSION.

8F7A  A592                LDA     EXEC            ; EXECUTE MODE?
8F7C  F007 ^8F85          BEQ     :XS090          ; NO.

8F7E  A593                LDA     EXPSTK          ; YES -- SET SPEED.
8F80  8D5D05              STA     SPEED

8F83  A900                LDA     #0              ; SET CC FOR EXIT.

8F85  60          :XS090  RTS                     ; RETURN WITH CC SET.



8F86                      PROC
                  ;
                  ; XCASS -- CASSETTE ON/OFF COMMAND PROCESSOR
                  ;
8F86  A20A        XCASS   LDX     #ONOFFX         ; CHECK FOR 'ON' OR 'OFF'
8F88  20AB7C              JSR     SBCMAT
8F8B  D00C ^8F99          BNE     :XC090          ; NOT FOUND -- ERROR.

8F8D  A592                LDA     EXEC            ; EXECUTE MODE?
8F8F  F008 ^8F99          BEQ     :XC090          ; NO.

8F91  BD9A8F              LDA     CASCTL,X        ; 0/1 -> CASSETTE CONTROL.
8F94  8D02D3              STA     PACTL


8F97  A900                LDA     #0              ; SET CC FOR NORMAL EXIT.

8F99  60          :XC090  RTS                     ; RETURN WITH CC SET.

                  ; CASSETTE CONTROL
                  ; REQUIRES KOFF = 0, KON = 1.

8F9A  3C          CASCTL  DB      CASSOF
8F9B  34                  DB      CASSON


8F9C                      PROC
                  ;
                  ; XCSYNC -- CASSETTE SYNC COMMAND PROCESSOR
                  ;
8F9C  F01B ^8FB9  XCSYNC  BEQ     :XC090          ; SYNTAX SCAN.

8F9E  AD02D3              LDA     PACTL           ; CHECK CASSETTE MOTOR.
8FA1  2908                AND     #$08
8FA3  D012 ^8FB7          BNE     :XC080          ; MOTOR OFF.

8FA5  A910                LDA     #$10            ; ON -- WAIT FOR MARK TO SPACE TRANSITION.

8FA7  207E9F      :XC010  JSR     ABRTCK          ; WAIT FOR BREAK ...
8FAA  2C0FD2              BIT     SKSTAT
8FAD  F0F8 ^8FA7          BEQ     :XC010          ; ... OR MARK.

8FAF  207E9F      :XC020  JSR     ABRTCK          ; WAIT FOR BREAK ...
8FB2  2C0FD2              BIT     SKSTAT
8FB5  D0F8 ^8FAF          BNE     :XC020          ; ... OR SPACE.

8FB7  A900        :XC080  LDA     #0              ; SET CC FOR NORMAL EXIT.

8FB9  60          :XC090  RTS                     ; RETURN WITH CC SET.

8FBA                      PROC
                  ;
                  ; XTRACE -- TRACE MODE ON/OFF COMMAND
                  ;
8FBA  A20A        XTRACE  LDX     #ONOFFX         ; CHECK FOR 'ON' OR 'OFF'.

8FBC  20AB7C              JSR     SBCMAT
8FBF  D009 ^8FCA          BNE     :XT090          ; NOT FOUND -- ERROR.

8FC1  A592                LDA     EXEC            ; EXECUTE MODE?
8FC3  F005 ^8FCA          BEQ     :XT090          ; NO.

                  ; REQUIRES KOFF = 0, KON <> 0.

8FC5  8E3505              STX     TRACE           ; SET FLAG.
8FC8  A900                LDA     #0              ; SET CC FOR NORMAL EXIT.

8FCA  60          :XT090  RTS                     ; RETURN WITH CC SET.

8FCB                      PROC
                  ;
                  ; XSAVE -- SAVE COMMAND PROCESSOR
                  ;
8FCB  20D696      XSAVE   JSR     DNAME           ; EXTRACT DEVICE/FILENAME.
8FCE  20079F              JSR     SKPSEP          ; SKIP SEPARATOR(S).

8FD1  A592                LDA     EXEC            ; EXECUTE MODE?
8FD3  F024 ^8FF9          BEQ     :XS090          ; NO.

8FD5  A230                LDX     #IOCB3
8FD7  A908                LDA     #OWRIT          ; YES -- OPEN DEVICE FOR OUTPUT.
8FD9  20F496              JSR     DOPEN

8FDC  A90B                LDA     #PUTC           ; SETUP IOCB FOR PUT CHARACTER.
8FDE  9D4203              STA     ICCOM,X

8FE1  A9B0                LDA     #$80+IOCB3      ; RE-ROUTE 'CHOT' OUTPUT TO DEVICE.
8FE3  8D3005              STA     CDEST

8FE6  20B490              JSR     LISTER          ; OUTPUT PROGRAM TO DEVICE.

8FE9  A230                LDX     #IOCB3
8FEB  203F97              JSR     DCLOSE          ; CLOSE DEVICE.

8FEE  A906                LDA     #EPUTC-IOVBAS   ; RESTORE 'CHOT' OUTPUT.
8FF0  8D3005              STA     CDEST

                  ; *** EXTERNAL ENTRY POINT FROM 'XLIST' ***

8FF3  202CB5      XSV050  JSR     RDYMES          ; GENERATE "READY" MESSAGE.

8FF6  A900                LDA     #0              ; SET CC FOR NORMAL EXIT.

8FF8              XAP090
8FF8              XME090
8FF8              XLO090
8FF8  60                  RTS                     ; RETURN WITH CC SET.

8FF9  4CB490      :XS090  JMP     LISTER          ; SYNTAX CHECK & RETURN WITH CC SET.

8FFC                      PROC
                  ;
                  ; XLOAD -- LOAD COMMAND PROCESSOR
                  ;
8FFC  201090      XLOAD   JSR     XLO100          ; COMMON CODE.
8FFF  D0F7 ^8FF8          BNE     XLO090          ; ERROR.

                  ; *** EXTERNAL ENTRY FROM 'XRUN' ***

9001  A592        XLO005  LDA     EXEC            ; EXECUTE MODE?
9003  F0F3 ^8FF8          BEQ     XLO090          ; NOT.

9005  20C087              JSR     CLRPRG          ; CLEAR PROGRAM STORAGE AREA.
9008  A901                LDA     #KLOAD          ; SET LOAD FLAG.

                  ; *** EXTERNAL ENTRY FROM 'XMERGE', 'XARPND' ***

900A  8D3205      XLO010  STA     LOADFG

900D  4C0979              JMP     MLLOAD          ; LOAD UNTIL I/O ERROR OR END OF FILE.
                                                  ; SET 'GETCOM'.

9010  20C297      XLO100  JSR     SFNAME          ; EXTRACT DEVICE/FILENAME.
9013  D0E3 ^8FF8          BNE     XLO090          ; ERROR.

9015  A592                LDA     EXEC            ; EXECUTE MODE?
9017  F0DF ^8FF8          BEQ     XLO090          ; NO.

9019  AD3205              LDA     LOADFG          ; ALREADY LOADING?

901C  D0DA ^8FF8          BNE     XLO090          ; YES -- ERROR.

901E  A230                LDX     #IOCB3
9020  A904                LDA     #OREAD          ; YES -- OPEN DEVICE FOR READING.
9022  20F496              JSR     DOPEN

9025  A900                LDA     #0              ; CLEAR USE STACK.
9027  8D4D05              STA     USTKP

902A  60                  RTS


                  ;
                  ; XMERGE -- MERGE COMMAND
                  ;
902B  201090      XMERGE  JSR     XLO100          ; COMMON CODE.
902E  D0C8 ^8FF8          BNE     XME090          ; ERROR.

9030  A592                LDA     EXEC            ; EXECUTE MODE?

9032  F0C4 ^8FF8          BEQ     XME090          ; NO.

9034  A902                LDA     #KMERGE         ; SET LOAD FLAG.
9036  D0D2 ^900A          BNE     XLO010          ; (BRA).

                  ;
                  ; XAPPND -- APPEND COMPAND PROCESSOR.
                  ;
9038  201090      XAPPND  JSR     XLO100          ; COMMON CODE.
903B  D0BB ^8FF8          BNE     XAP090          ; ERROR.

903D  201A91              JSR     XAU010          ; SHARE 'XAUTO' CODE FOR LINE #'S.
9040  D0B6 ^8FF8          BNE     XAP090          ; ERROR.

9042  A592                LDA     EXEC            ; EXECUTE MODE?
9044  F0B2 ^8FF8          BEQ     XAP090          ; NO.

9046  A903                LDA     #KAPPND         ; SET LOAD FLAG.
9048  D0C0 ^900A          BNE     XLO010          ; (BRA).

904A                      PROC
                  ;
                  ; XLETTR -- TEXT LETTER SIZE SELECTION
                  ;
904A  A20C        XLETTR  LDX     #LTTABX         ; CHECK FOR 'SMALL', 'MEDIUM', OR 'LARGE'.
904C  20AB7C              JSR     SBCMAT
904F  D02D ^907E          BNE     :XL090          ; NOT FOUND -- ERROR.

9051  A592                LDA     EXEC            ; EXECUTE MODE?
9053  F029 ^907E          BEQ     :XL090          ; NO.

9055  AD4505              LDA     SGLSTP          ; SINGLE STEP?
9058  F004 ^905E          BEQ     :XL020          ; NO.

905A  A983                LDA     #NRCERR         ; YES -- ERROR.
905C  D020 ^907E          BNE     :XL090

905E  84AB        :XL020  STY     XTEMP
9060  8E5105              STX     LETTRSZ         ; YES -- SET NEW LETTER SIZE.
9063  8A                  TXA
9064  D006 ^906C          BNE     :XL050          ; MEDIUM OR LARGE LETTERS.

9066  20F494              JSR     TXOPEN          ; SMALL LETTERS.
9069  4C7790              JMP     :XL080

906C  8E3705      :XL050  STX     GSMODE          ; GRAPHICS MODE.
906F  A900                LDA     #0
9071  8D5205              STA     SPLTSC          ; NO SPLIT SCREEN.

9074  201095              JSR     GSOPEN          ; OPEN SCREEN.

9077  A4AB        :XL080  LDY     XTEMP
9079  A900                LDA     #0              ; RESET GRAPHICS MODE FLAG & SET CC.
907B  8D1405              STA     GRFLAG

907E  60          :XL090  RTS                     ; RETURN WITH CC SET.
907F                      PROC
                  ;
                  ; XSCROLL -- SCROLL OPTION SELECTION
                  ;
907F  A210        XSCROLL LDX     #SCTABX         ; CHECK FOR 'FINE' OP 'COARSE'.
9081  20AB7C              JSR     SBCMAT
9084  D01D ^90A3          BNE     :XS090          ; NOT FOUND -- ERROR.

9086  A592                LDA     EXEC            ; EXECUTE MODE?
9088  F019 ^90A3          BEQ     :XS090          ; NO.

908A  20BB96              JSR     TSTMOD          ; TEXT MODE, SMALL LETTERS?
908D  C901                CMP     #TXSL
908F  D013 ^90A4          BNE     :XS092          ; NO.

9091  8EB205              STX     FINEFG          ; SET SCREEN EDITOR FLAG.
9094  84AB                STY     XTEMP
9096  202996              JSR     COMPRS          ; COMPRESS MEMORY.
9099  208E96              JSR     EOPEN           ; RE-OPEN E: ON IOCB 0.

909C  205C96              JSR     EXPAND          ; EXPAND MEMORY.
909F  A4AB                LDY     XTEMP

90A1  A900                LDA     #0              ; SET CC FOR NORMAL EXIT

90A3  60          :XS090  RTS                     ; RETURN WITH CC SET.

90A4  A983        :XS092  LDA     #NRCERR
90A6  60                  RTS


90A7                      PROC
                  ;
                  ; XLIST -- LIST COMMND PROCESSOR
                  ;

                  ; *** EXTERNAL ENTRY POINT FROM 'XSAVE' ***

90A7  20B490      XLIST   JSR     LISTER          ; DO THE LIST PROCESS.
90AA  D007 ^90B3          BNE     :XL009          ; ERROR.

90AC  A592                LDA     EXEC            ; EXECUTE MODE?
90AE  F003 ^90B3          BEQ     :XL009          ; NO.
90B0  4CF38F              JMP     XSV050          ; YES -- SIGN OFF & RETURN.

90B3  60          :XL009  RTS                     ; RETURN WITH CC SET.

90B4  A90D        LISTER  LDA     #LOW LSTNMS     ; ADDRESS OF DEFAULTS.
90B6  85B6                STA     POINT
90B8  A991                LDA     #HIGH LSTNMS
90BA  85B7                STA     POINT+1
90BC  206D93              JSR     MNYNMS          ; GET PARAMETERS.
90BF  D045 ^9106          BNE     :XL900          ; SYNTAX ERROR.

90C1  E003                CPX     #3
90C3  B041 ^9106          BCS     :XL900          ; TOO MANY NUMBERS.

90C5  E001                CPX     #1              ; HOW MANY ARGS?
90C7  D00C ^90D5          BNE     :XL010          ; 0 OR 2.

90C9  AD5305              LDA     NMSBF           ; 1 -- LAST LINE = FIRST.
90CC  8D5505              STA     NMSBF+2
90CF  AD5405              LDA     NMSBF+1
90D2  8D5605              STA     NMSBF+3

90D5              :XL010

                  ; *S*   STY     XTEMP           ; SAVE Y.
90D5  A25E                LDX     #LS-DTAB        ; 'LS'= FIRST.
90D7  A000                LDY     #0
90D9  207794              JSR     NMOVI

90DC  A260                LDX     #LEND-DTAB      ; 'LEND' = SECOND.
90DE  A002                LDY     #2
90E0  207794              JSR     NMOVI

90E3  20C893              JSR     BRACKT          ; BRACKET RANGE.
90E6  D01E ^9106          BNE     :XL900          ; FIRST > LAST.

90E8  A592                LDA     EXEC            ; EXECUTE MODE?
90EA  F01C ^9108          BEQ     :XL990          ; NO.

90EC  A213        :XL100  LDX     #BLOW-DTAB      ; ADDRESS OF NEXT LINE
90EE  A015                LDY     #BHIGH-DTAB     ; ADDRESS PAST END.
90F0  20159C              JSR     DCMPI
90F3  B00D ^9102          BCS     :XL200          ; DONE.

90F5  A013                LDY     #BLOW-DTAB

90F7  20229F              JSR     PSF             ; PRINT STORAGE FORM LINE.

90FA  A213                LDX     #BLOW-DTAB      ; ADVANCE TO NEXT LINE.
90FC  20AA9A              JSR     SNXTI
90FF  4CEC90              JMP     :XL100

9102  A900        :XL200  LDA     #0              ; SET CC FOR NORMAL EXIT.
9104  F002 ^9108          BEQ     :XL990          ; (BRA).

9106  A902        :XL900  LDA     #IMPERR         ; IMPROPER PARAMETER ERROR.

9108  08          :XL990  PHP                     ; SAVE CC.
9109  A4AB                LDY     XTEMP             ; RESTORE Y.
910B  28                  PLP                     ; RESTORE CC.
910C  60                  RTS                     ; RETURN KITH CC SET.

                  ; DEFAULTS FOR 'LIST'.

910D  0000        LSTNMS  DW      0
910F  0F27                DW      MAXLN
9111  FFFF                DW      EONMLS


9113                      PROC
                  ;
                  ; XAUTO -- AUTO-INPUT COMMAND PROCESSOR
                  ;
9113  201A91      XAUTO   JSR     XAU010          ; COMMON CODE.
9116  D04A ^9162          BNE     :XA900          ; ERROR.
9118  F030 ^914A          BEQ     :XA200

                  ; *** EXTERNAL ENTRY FOR 'APPEND' ***

911A  A969        XAU010  LDA     #LOW AUTNMS     ; ADDRESS OF DEFAULTS.
911C  85B6                STA     POINT
911E  A991                LDA     #HIGH AUTNMS
9120  85B7                STA     POINT+1
9122  206D93              JSR     MNYNMS          ; GET PARAMETERS.
9125  D022 ^9149          BNE     :XA190          ; SYNTAX ERROR.

                  ; *S*   STY     XTEMP           ; SAVE Y.
9127  8A                  TXA                     ; SET 'Z' FLAG.
9128  D00D ^9137          BNE     :XA100          ; FIRST LINE ENTERED.

                  ; DEFAULTS: NEXT LINE = LAST PROGRAM LINE + 10

912A  201294              JSR     GTLSLN          ; 'LINE NO' = LAST PROGRAM LINE + 10
912D  A27A                LDX     #ALINE-DTAB
912F  A05C                LDY     #LINENO-DTAB
9131  20459A              JSR     DMOVI
9134  4C3E91              JMP     :XA110

                  ; USE ENTERED VALUES.

9137  A27A        :XA100  LDX     #ALINE-DTAB     ; 'ALINE' = FIRST.
9139  A000                LDY     #0
913B  207794              JSR     NMOVI

913E  A27C        :XA110  LDX     #AINC-DTAB      ; 'AINC' = SECOND.
9140  A002                LDY     #2
9142  207794              JSR     NMOVI
9145  A4AB                LDY     XTEMP           ; RESTORE Y.
9147  A900                LDA     #0              ; SET CC FOR EXIT.

9149  60          :XA190  RTS

914A  A592        :XA200  LDA     EXEC            ; EXECUTE MODE?
914C  F016 ^9164          BEQ     :XA990          ; NO.

914E  8D3605              STA     AUTOIN          ; YES -- SET AUTO-INPUT MODE;
9151  A586                LDA     ACOLR2          ; SET SCREEN BACKGROUND COLOR.
9153  8DC602              STA     COLOR0+2
9156  A587                LDA     ACOLR1          ; SET SCREEN LETTER COLOR.
9158  8DC502              STA     COLOR0+1

915B  A900                LDA     #0              ; SET CC FOR NORMAL EXIT.
915D  8DCA05              STA     INDENT          ; INITIALIZE 'AUTO INDENT'.

9160  F002 ^9164          BEQ     :XA990          ; (BRA).


9162  A902        :XA900  LDA     #IMPERR

9164  08          :XA990  PHP                     ; SAVE CC.
9165  A4AB                LDY     XTEMP           ; RESTORE Y.
9167  28                  PLP                     ; RESTORE CC.
9168  60                  RTS

                  ; DEFAULTS FOR 'AUTO', 'APPEND'

9169  0000        AUTNMS  DW      0  ; (DON'T CARE)
916B  0A00                DW      10
916D  FFFF                DW      EONMLS



916F                      PROC
                  ;
                  ; XDELET -- DELETE COMMAND PROCESSOR
                  ;
916F  A90D        XDELET  LDA     #LOW LSTNMS     ; SHARE DEFAULTS.
9171  85B6                STA     POINT
9173  A991                LDA     #HIGH LSTNMS
9175  85B7                STA     POINT+1
9177  206D93              JSR     MNYNMS          ; GET PARAMETERS.
917A  D07C ^91F8          BNE     :XD900          ; SYNTAX ERROR.

917C  E001                CPX     #1              ; 0, 1, OR 2 PARAMETERS.
917E  9078 ^91F8          BCC     :XD900          ; 0 = ERROR.
9180  D00C ^918E          BNE     :XD010          ; 2.

9182  AD5305              LDA     NMSBF           ; 1 -- LAST LINE = FIRST.
9185  8D5505              STA     NMSBF+2
9188  AD5405              LDA     NMSBF+1
918B  8D5605              STA     NMSBF+3

918E              :XD010
                  ; *S*   STY     XTEMP           ; SAVE Y.
918E  A25E                LDX     #LS-DTAB        ; 'LS' = FIRST.
9190  A000                LDY     #0
9192  207794              JSR     NMOVI

9195  A260                LDX     #LEND-DTAB      ; 'LEND' = SECOND.
9197  A002                LDY     #2
9199  207794              JSR     NMOVI

919C  20C893              JSR     BRACKT          ; BRACKET RANGE.
919F  D057 ^91F8          BNE     :XD900          ; FIRST > LAST.

91A1  A592                LDA     EXEC            ; EXECUTE MODE?
91A3  F055 ^91FA          BEQ     :XD990          ; NO.

91A5  A597                LDA     BNUM            ; ANY LINES TO DELETE?
91A7  0598                ORA     BNUM+1
91A9  F049 ^91F4          BEQ     :XD600          ; NO.

                  ; WARN USER.

91AB  A99F                LDA     #DELMES         ; 'YOU ARE ABOUT TO DELETE '.
91AD  20FFB4              JSR     MESSOT

91B0  A217                LDX     #BNUM-DTAB      ; # OF LINES.
91B2  20149E              JSR     DECASC

91B5  A9A0                LDA     #DL2MES         ; 'LINES(S).<CR> ARE YOU SURE?'
91B7  20FFB4              JSR     MESSOT

91BA  A20C                LDX     #TELN-DTAB      ; USE 'TEXBUF'.
91BC  20B194              JSR     GETLIN
91BF  A58F                LDA     TELN+3          ; EMPTY?
91C1  F02C ^91EF          BEQ     :XD500          ; YES -- DO NOT CHANGE.

91C3  AD00BC              LDA     TEXBUF          ; FIRST CHARACTER.
91C6  0920                ORA     #LC             ; FORCE LOWER CASE.
91C8  C979                CMP     #'Y'+$20        ; Y?
91CA  D023 ^91EF          BNE     :XD500          ; NO -- DO NOT CHANGE.

                  ; USER AGREES.

91CC  8D4305              STA     NOCONT          ; NO CONTINUE AFTER DELETIONS.
91CF  A215                LDX     #BHIGH-DTAB     ; SIZE OF BRACKETED RANGE.
91D1  A013                LDY     #BLOW-DTAB
91D3  20429C              JSR     DSUBI

91D6  A252                LDX     #MEMA-DTAB      ; GET READY TO DELETE.
                  ; *S*   LDY     #BLOW-DTAB
91D8  20459A              JSR     DMOVI

91DB  A000                LDY     #0              ; SET BLOCK SIZE TO DELETE.
91DD  A595                LDA     BHIGH
91DF  9193                STA     (BLOW),Y
91E1  C8                  INY
91E2  A596                LDA     BHIGH+1
91E4  9193                STA     (BLOW),Y

91E6  203E9B              JSR     MDEALL          ; DELETE BLOCK.

91E9  202CB5              JSR     RDYMES
                  ;       LDA     #0              ; SET CC FOR NORMAL EXIT.
                  ;       BEQ     :XD990          ; (BRA).
91EC  4CF491              JMP     :XD600

                  ; USER DOES NOT AGREE.

91EF  A99E        :XD500  LDA     #NCHGMS         ; 'PROGRAM UNCHANGED'.
91F1  20FFB4              JSR     MESSOT

91F4  A900        :XD600  LDA     #0              ; SET CC FOR NORMAL EXIT.
91F6  F002 ^91FA          BEQ     :XD990

                  ; SYNTAX ERROR.

91F8  A902        :XD900  LDA     #IMPERR         ; IMPROPER PARAMETER ERROR.

91FA  08          :XD990  PHP                     ; SAVE CC.
91FB  A4AB                LDY     XTEMP           ; RESTORE Y.
91FD  28                  PLP                     ; RESTORE CC.
91FE  60                  RTS

91FF                      PROC
                  ;
                  ; XREN -- RENUMBER COMMAND PROCESSOR
                  ;
                  ;       STEP 1: BRACKET T HE RANGE OF LINES TO RENUMBER.
                  ;            2: COMPUTE THE NEW RANGE THEY WILL BECOME.
                  ;            3: FIND STARTING AND ENDING ADDRESSES OF THE NEW LINES.
                  ;            4: THERE ARE TWO VALID CASES FOR THE NEW LINES:
                  ;                  A. THEY ALL FIT BETWEEN TWO EXISTING LINES.
                  ;                  B. THEY ALL FIT WITHIN THE RENUMBERED RANGE.
                  ;            5: RENUMBER THE LINES IN PLACE.
                  ;            6: MOVE THEM BETWEEN TWO EXISTING LINES (IF 4A.).
                  ;
91FF  A963        XREN    LDA     #LOW RENNMS     ; ADDRESS OF DEFAULTS.
9201  85B6                STA     POINT
9203  A993                LDA     #HIGH RENNMS
9205  85B7                STA     POINT+1
9207  206D93              JSR     MNYNMS          ; GET PARAMETERS.
920A  F003 ^920F          BEQ     :XR010          ; OK.
920C  4C5E93      :XR005  JMP     :XR900          ; SYNTAX ERROR.

920F              :XR010
                  ; *S*   STY      XTEMP          ; SAVE Y.

920F  A27A                LDX     #ALINE-DTAB     ; 'ALINE' = FIRST.
9211  A000                LDY     #0
9213  207794              JSR     NMOVI

9216  A27C                LDX     #AINC-DTAB      ; 'AINC' = SECOND.
9218  A002                LDY     #2
921A  207794              JSR     NMOVI

921D  A25E                LDX     #LS-DTAB        ; 'LS' = THIRD.
921F  A004                LDY     #4
9221  207794              JSR     NMOVI

9224  A260                LDX     #LEND-DTAB      ; 'LEND' = FOURTH.
9226  A006                LDY     #6
9228  207794              JSR     NMOVI

922B  20C893              JSR     BRACKT          ; BRACKET RANGE.
922E  D0DC ^920C          BNE     :XR005          ; 'LS' > 'LEND'.

9230  A592                LDA     EXEC            ; EXECUTE M100E?
9232  D003 ^9237          BNE     :XR015          ; YES.
9234  4C5E93              JMP     :XR990          ; NO.

9237  A597        :XR015  LDA     BNUM            ; 0 LINES?
9239  0598                ORA     BNUM+1
923B  D003 ^9240          BNE     :XR020          ; NO.
923D  4C2E93              JMP     :XR500          ; YES.

9240  A219        :XR020  LDX     #RTMP-DTAB      ; 'RTMP' = # OF LINES.
9242  A017                LDY     #BNUM-DTAB
9244  20459A              JSR     DMOVI
9247  20129D              JSR     DDCRI           ; -1.

924A  A07C                LDY     #AINC-DTAB      ; INCREMENT.
924C  20549C              JSR     DMULI
924F  A07A                LDY     #ALINE-DTAB     ; # FIRST NEW LINE.
9251  20329C              JSR     DADDI           ; # LAST NEW LINE.

9254  206B94              JSR     CHKLN           ; IS LINE IN RANGE?
9257  9003 ^925C          BCC     :XR030          ; YES.
9259  4C3593              JMP     :XR600          ; NO -- OUT OF RANGE.

                  ; FIND STARTING AND ENDING ADDRESSES OF THE NEW RANGE.

925C              :XR030
                  ; *S*   LDX     #RTMP-DTAB      ; 'RTMP' = LAST NEW LINE;
925C  204294              JSR     RENFND
925F  85AC                STA     XTEMP+1         ; SAVE 'VALID' STATUS.

9261  A21B                LDX     #R2TMP-DTAB     ; 'R2TMP' = ADDRESS OF END.
9263  A04E                LDY     #PP-DTAB
9265  20459A              JSR     DMOVI

9268  A27A                LDX     #ALINE-DTAB
926A  204294              JSR     RENFND          ; 'PP' = ADDRESS OF START.
926D  05AC                ORA     XTEMP+1         ; IF EITHER IS INVALID, "OVERLAP" ERROR.
926F  F003 ^9274          BEQ     :XR040          ; OK.
9271  4C4293      :XR035  JMP     :XR700          ; OVERLAP.

                  ;
                  ; OVERLAPPING RANGES UNLESS:
                  ;       'START' OF NEW = 'END' OF NEW *OR*
                  ;       'START' OF OLD <= 'START' OF NEW *AND*
                  ;       'END' OF NEW <= 'END' OF OLD
                  ;
9274  A24E        :XR040  LDX     #PP-DTAB        ; 'START' OF NEW.
9276  A01B                LDY     #R2TMP-DTAB     ; 'END' OF NEW.
9278  20159C              JSR     DCMPI
927B  F010 ^928D          BEQ     :XR100          ; NOT OVERLAPPING.

                  ; *S*   LDX     #PP-DTAB        ; 'START' OF NEW.
927D  A013                LDY     #BLOW-DTAB      ; 'START' OF OLD.
927F  20159C              JSR     DCMPI
9282  90ED ^9271          BCC     :XR035          ; OVERLAPPING.

9284  A215                LDX     #BHIGH-DTAB     ; 'END' OF NEW.
9286  A01B                LDY     #R2TMP-DTAB     ; 'END' OF OLD.
9288  20159C              JSR     DCMPI
928B  90E4 ^9271          BCC     :XR035          ; OVERLAPPING.

                  ; RENUMBER IS VALID

928D  A219        :XR100  LDX     #RTMP-DTAB
928F  A04E                LDY     #PP-DTAB
9291  20459A              JSR     DMOVI           ; 'RTMP' = ADDRESS OF START.

                  ; RENUMBER EACH LINE IN PLACE

9294  8D4305      :XR110  STA     NOCONT
9297  A24E                LDX     #PP-DTAB        ; NO CONTINUE AFTER RENUMBER.
9299  A013                LDY     #BLOW-DTAB
929B  20459A              JSR     DMOVI

                  ; 'PP     = ADDRESS OF NEXT LINE TO RENUMBER.
                  ; 'ALINE' = NEW LINE NUMBER.
                  ; 'AINC'  = INCREMENT.
                  ; 'BNUM'  = # OF LINES LEFT TO RENUMBER.


929E  A004        :XR200  LDY     #4
92A0  A5FA                LDA     ALINE
92A2  91CE                STA     (PP),Y          ; NEW LSB (INVERTED).

92A4  88                  DEY
92A5  A5FB                LDA     ALINE+1
92A7  91CE                STA     (PP),Y          ; NEW MSB (INVERTED).

92A9  A27A                LDX     #ALINE-DTAB
92AB  A07C                LDY     #AINC-DTAB
92AD  20329C              JSR     DADDI           ; INCREMENT 'ALINE'.

92B0  A24E                LDX     #PP-DTAB
92B2  20AA9A              JSR     SNXTI           ; ADDRESS OF NEXT LINE.
92B5  A217                LDX     #BNUM-DTAB
92B7  20129D              JSR     DDCRI           ; ONE LESS LINE.

92BA  A597                LDA     BNUM            ; ANY LINES LEFT?
92BC  0598                ORA     BNUM+1
92BE  D0DE ^929E          BNE     :XR200          ; YES.

                  ; THE LINES HAVE BEEN RENUMBERED IN PLACE.

                  ; THERE ARE FOUR CASES:
                  ;    1. 'START' ADDRESS < 'END' ADDRESS -> ALREADY IN ORDER.
                  ;    2. ONE LINE MOVE, ALREADY IN ORDER (NEW = OLD).
                  ;    3. MOVE THE BLOCK TO LOWER MEMORY (NEW #'S < OLD).
                  ;    4. MOVE THE BLCCK TO HIGHER MEMORY ( NEW #'S > OLD).

92C0  A219                LDX     #RTMP-DTAB      ; 'START' ADDRESS.
92C2  A01B                LDY     #R2TMP-DTAB     ; 'END' ADDRESS.
92C4  20159C              JSR     DCMPI
92C7  D065 ^932E          BNE     :XR500          ; ALREADY IN ORDER.

                  ; MOVE ONE STATEMENT AT A TIME (TO AVOID 'NOT ENOUGH MEMORY'), USING 'TEXBUF'.

                  ; 'BLOW'  = ADDRESS OF NEXT STATEMENT TO MOVE.
                  ; 'BHIGH' = ADDRESS PAST END.

                  ; *S*   LDX     #RTMP-DTAB
92C9  A013                LDY     #BLOW-DTAB
92CB  20159C              JSR     DCMPI           ; IS 'NEW' < 'OLD'?
92CE  F05E ^932E          BEQ     :XR500          ; NEW = OLD.
92D0  A900                LDA     #0              ; SET 'NEW' < 'OLD'.
92D2  9002 ^92D6          BCC     :XR210          ; YES.

92D4  A901                LDA     #1              ; NO -- SET 'NEW' > 'OLD'.
92D6  859B        :XR210  STA     R2TMP

92D8  A000        :XR300  LDY     #0              ; GET LENGTH OF STATEMENT.
92DA  B193                LDA     (BLOW),Y
92DC  A8                  TAY

92DD  B193        :XR310  LDA     (BLOW),Y        ; MOVE NEXT RYTE TO 'TEXBUF'.
92DF  9900BC              STA     TEXBUF,Y        ; (EXTRA BYTE IS "DON'T CARE").
92E2  88                  DEY
92E3  10F8 ^92DD          BPL     :XR310

92E5  A252                LDX     #MEMA-DTAB
92E7  A013                LDY     #BLOW-DTAB
92E9  20459A              JSR     DMOVI           ; 'MEMA' = ADDRESS IN STORAGE.

92EC  203E9B              JSR     MDEALL          ; DELETE IT.

92EF  A59B                LDA     R2TMP           ; 'NEW' > 'OLD'?
92F1  D00A ^92FD          BNE     :XR320          ; YES.

                  ; 'NEW' < 'OLD'.

92F3  A213                LDX     #BLOW-DTAB
92F5  A054                LDY     #MEMB-DTAB
92F7  20329C              JSR     DADDI           ; ADJUST 'BLOW' FOR NEXT LINE.
92FA  4C0993              JMP     :XR330

                  ; 'NEW' > 'OLD'.

92FD  A219        :XR320  LDX     #RTMP-DTAB
92FF  A054                LDY     #MEMB-DTAB
9301  20429C              JSR     DSUBI           ; MOVE 'RTMP' FOR INSERTION.

9304  A215                LDX     #BHIGH-DTAB
                  ; *S*   LDY     #MEMB-DTAB
9306  20429C              JSR     DSUBI           ; ADJUST 'BHIGH' FOR NEXT LINE.

                  ; ALLOCATE A BLOCK AT 'RTMP'.

9309  A252        :XR330  LDX     #MEMA-DTAB
930B  A019                LDY     #RTMP-DTAB
930D  20459A              JSR     DMOVI

9310  20C19A              JSR     MALLOC          ; ? ALLOCATE IT (MUST BE ROOM).

9313  A4D4                LDY     MEMB            ; COPY STATEMENT FROM 'TEXBUF'.
9315  88                  DEY                     ; # - 1 OF BYTES.

9316  B900BC      :XR350  LDA     TEXBUF,Y
9319  9199                STA     (RTMP),Y
931B  88                  DEY
931C  10F8 ^9316          BPL     :XR350

                  ; STATEMENT HAS BEEN INSERTED.

931E  A219                LDX     #RTMP-DTAB
9320  A054                LDY     #MEMB-DTAB
9322  20329C              JSR     DADDI           ; ADJUST 'RTMP' FOR NEXT LINE.

                  ; ANY MORE TO MOVE?

9325  A213                LDX     #BLOW-DTAB
9327  A015                LDY     #BHIGH-DTAB
9329  20159C              JSR     DCMPI
932C  90AA ^92D8          BCC     :XR300          ; YES.

932E  202CB5      :XR500  JSR     RDYMES          ; ALL DONE.
9331  A900                LDA     #0              ; SET CC FOR NORMAL EXIT.
9333  F029 ^935E          BEQ     :XR990          ; (BRA).

                  ; ERROR -- MAXIMUM LINE NUMBER EXCEEDED.

9335  A99B        :XR600  LDA     #RENERR         ; CAN'T RENUMBER.
9337  20FFB4              JSR     MESSOT
933A  A98D                LDA     #LNOERR         ; LINE # OUT OF RANGE.
933C  20FFB4              JSR     MESSOT
933F  4C2E93              JMP     :XR500

                  ;
                  ; ERROR -- OVERLAPPING RANGE.
                  ;       'ALINE' FIRST NEW LINE.
                  ;       'RTMP'  LAST.

9342  A99B        :XR700  LDA     #RENERR         ; CAN'T RENUMBER.
9344  20FFB4              JSR     MESSOT
9347  A99C                LDA     #OVLPER         ; OVERLAPPING RANGE.
9349  20FFB4              JSR     MESSOT
934C  A27A                LDX     #ALINE-DTAB     ; FIRST NEW LINE.
934E  20149E              JSR     DECASC
9351  A99D                LDA     #TOMES          ; TO.
9353  20FFB4              JSR     MESSOT
9356  A219                LDX     #RTMP-DTAB      ; LAST NEW LINE.
9358  20149E              JSR     DECASC
935B  4C2E93              JMP     :XR500

                  ; ERROR -- SYNTAX.

935E              :XR900

                  ; EXIT.

935E  08          :XR990  PHP                     ; SAVE CC.
935F  A4AB                LDY     XTEMP           ; RESTORE Y.
9361  28                  PLP                     ; RESTORE CC.
9362  60                  RTS

                  ; DEFAULTS FOR 'RENUMBER'.

9363  0A00        RENNMS  DW      10              ; FIRST NEW.
9365  0A00                DW      10              ; INCREMENT.
9367  0000                DW      0               ; FIRST OLD.
9369  0F27                DW      MAXLN           ; LAST OLD.
936B  FFFF                DW      EONMLS


936D                      PROC
                  ;
                  ; MNYNMS -- RETURN 'MANY' NUMBERS FROM 'INLN'
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'INLN' POINTS TO THE STATEMENT LINE
                  ;       Y = CUPPENT OFFSET IN 'INLN'
                  ;       'POINT' = LIST OF VALUES FOR INITIALIZING 'NMSBF'
                  ;
                  ;       JSR MNYNMS
                  ;       BNE     SYNTAX ERROR, RANGE ERROR, OR TOO MANY NUMBERS (A=ERROR
                  ;               CODE)
                  ;
                  ;       X       = NUMBER OF NUMBERS FOUND.
                  ;       'NMSBF' = LIST OF NUMBERS
                  ;       Y       = CURRENT OFFSET IN 'INLN'
                  ;       XTEMP   = CURRENT OFFSET IN 'INLN'
                  ;
                  ;       'NMSBF' IS INITIALIZED FROM THE LIST ADDRESSED BY 'POINT'.
                  ;       'EONMLS' REPRESENTS THE END-OF-LIST.
                  ;       IF TOO MANY NUMER ARE IN THE SOURCE TEXT, AN ERROR CODE WILL BE
                  ;       RECOGNIZED.
                  ;
936D  84AB        MNYNMS  STY     XTEMP
936F  A000                LDY     #0              ; INITIALIZE 'NMSBF' FROM 'POINT'.

9371  B1B6        :MN010  LDA     (POINT),Y
9373  995305              STA     NMSBF,Y
9376  C8                  INY
9377  B1B6                LDA     (POINT),Y
9379  995305              STA     NMSBF,Y
937C  C8                  INY
937D  C9FF                CMP     #HIGH EONMLS    ; CHECK FOR END OF LIST.
937F  D0F0 ^9371          BNE     :MN010

9381  A4AB                LDY     XTEMP           ; RESTORE Y.
9383  A900                LDA     #0
9385  85B6                STA     POINT           ; INITIALIZE OFFSET TO STORE NEXT VALUE.

9387  20079F      :MN020  JSR     SKPSEP          ; SKIP LOADING SEPARATORS.
938A  206E81              JSR     ATOM            ; GET NEXT NUMBER.
938D  D032 ^93C1          BNE     :MN099          ; ERROR -- RETURN.

938F  C901                CMP     #NULL           ; CHECK FOR 'EOL'.
9391  F02E ^93C1          BEQ     :MN099          ; EOL -- DONE.

9393  C902                CMP     #NUM            ; CHECK FOR NUMBER.
9395  D028 ^93BF          BNE     :MN090          ; NO -- ERROR.

9397  84AB                STY     XTEMP           ; SAVE Y.
9399  A238                LDX     #NUMBER-DTAB    ; CHECK IF NUMBER IS IN RANGE.
939B  206B94              JSR     CHKLN
939E  B01B ^93BB          BCS     :MN080          ; NO -- OUT OF RANGE.

93A0  A6B6                LDX     POINT           ; INDEX IN 'NMSBF'.
93A2  A9FF                LDA     #$FF            ; CHECK IF TOO MANY VALUES.
93A4  DD5405              CMP     NMSBF+1,X
93A7  F016 ^93BF          BEQ     :MN090          ; YES -- TOO MANY.

93A9  A5B8                LDA     NUMBER          ; COPY TO NEXT POSITION IN 'NMSBF'.
93AB  9D5305              STA     NMSBF,X
93AE  A5B9                LDA     NUMBER+1
93B0  9D5405              STA     NMSBF+1,X
93B3  E8                  INX
93B4  E8                  INX
93B5  86B6                STX     POINT           ; UPDATE INDEX.

93B7  A4AB                LDY     XTEMP           ; RESTORE Y.
93B9  D0CC ^9387          BNE     :MN020          ; (BRA).

                  ; OUT OF RANGE

93BB  A98D        :MN080  LDA     #LNOERR
93BD  D002 ^93C1          BNE     :MN099          ; (BRA).

                  ; NEXT 'ATOM' IS NOT A NUMBER, OR TOO MANY NUMBERS.

93BF  A902        :MN090  LDA     #IMPERR         ; IMPROPER PARAMETER ERROR.

93C1  08          :MN099  PHP                     ; SAVE CC.
93C2  A5B6                LDA     POINT           ; INDEX IN 'NMSBF'.
93C4  4A                  LSR     A
93C5  AA                  TAX                     ; AS ADVERTISED.
93C6  28                  PLP
93C7  60                  RTS


93C8                      PROC
                  ;
                  ; BRACKT -- BRACKET A RANGE OF LINES
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'LS'    = START OF RANGE
                  ;       'LEND'  = END
                  ;
                  ;       JSR     BRACKT
                  ;       BNE     'LS' > 'LEND'
                  ;
                  ;       'BLOW'  = ADDRESS OF START OF RANGE
                  ;       'BHIGH' = ADDRESS OF (PAST) END OF RANGE
                  ;       'BNUM'  = # OF LINES IN THE RANGE
                  ;
                  ;       USES 'LINENO', 'POINT'
                  ;

93C8  A260        BRACKT  LDX     #LEND-DTAB      ; CHECK IF 'LS' <= 'LEND
93CA  A05E                LDY     #LS-DTAB
93CC  20159C              JSR     DCMPI
93CF  9040 ^9411          BCC     :BR090          ; ERROR -- 'LS' > 'LEND'

93D1  A900                LDA     #0              ; INITIALIZE # OF LINES.
93D3  8597                STA     BNUM
93D5  8598                STA     BNUM+1

93D7  A25E                LDX     #LS-DTAB
93D9  205D94              JSR     LNFIND

93DC  A213                LDX     #BLOW-DTAB      ; 'BLOW' = ADDRESS OF 'LS' OR SUCCESSOR.
93DE  A04E                LDY     #PP-DTAB
93E0  20459A              JSR     DMOVI
93E3  A236                LDX     #POINT-DTAB     ; USE 'POINT' FOR CURRENT LINE ADDRESS.
93E5  20459A              JSR     DMOVI

93E8              :BR010
                  ; *S*   LDX     #POINT-DTAB
93E8  20139A              JSR     SEND            ; CHECK IF END OF LIST.
93EB  F01B ^9408          BEQ     :BR050          ; YES -- DONE.

93ED  208C9F              JSR     GTLNNO          ; 'LINENO' IN L/H ORDER FROM 'POINT'.
93F0  A260                LDX     #LEND-DTAB      ; CHECK IF CURRENT LINE IS IN RANGE.
93F2  A05C                LDY     #LINENO-DTAB
93F4  20159C              JSR     DCMPI
93F7  900F ^9408          BCC     :BR050          ; NO -- NOT IN RANGE.

93F9  A901                LDA     #1              ; ONE MORE LINE IN RANGE.
93FB  A217                LDX     #BNUM-DTAB
93FD  20049D              JSR     DADDS

9400  A236                LDX     #POINT-DTAB     ; POINT TO NEXT LINE.
9402  20AA9A              JSR     SNXTI
9405  4CE893              JMP     :BR010          ; CHECK NEXT LINE.

                  ; CURRENT LINE IS NOT IN THE RANGE.

9408  A215        :BR050  LDX     #BHIGH-DTAB     ; AS ADVERTISED.
940A  A036                LDY     #POINT-DTAB
940C  20459A              JSR     DMOVI

940F  A900                LDA     #0              ; SET CC FOR EXIT.
                  ; +S*   RTS

                  ; ERROR -- 'LS' > 'LEND'

9411  60          :BR090  RTS

9412                      PROC
                  ;
                  ; GTLSLN -- GET LINE NUMBER OF LAST PROGRAM LINE + 10
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       JSR     GTLSLN
                  ;
                  ;       'LINENO' = LAST LINE NUMBER + 10 (0 IF EMPTY).
                  ;
9412  84AB        GTLSLN  STY     XTEMP           ; SAVE Y.
9414  A900                LDA     #0              ; 'EMPTY' VALUE.
9416  85DC                STA     LINENO
9418  85DD                STA     LINENO+1
941A  209F9E              JSR     STMLST          ; 'LP' = 'S1L'

941D  A23A                LDX     #LP-DTAB
941F  20139A              JSR     SEND            ; TRAP FOR PROGRAM EMPTY.
9422  F014 ^9438          BEQ     :GL090          ; EMPTY.

9424  A03A        :GL010  LDY     #LP-DTAB        ; UPDATE 'POINT'.
9426  A236                LDX     #POINT-DTAB
9428  20459A              JSR     DMOVI

942B  A23A                LDX     #LP-DTAB        ; NEXT LINE.
942D  20AA9A              JSR     SNXTI
9430  20139A              JSR     SEND
9433  D0EF ^9424          BNE     :GL010          ; KEEP CHECKING.

9435  208C9F              JSR     GTLNNO          ; 'LINENO' FROM 'POINT'.

9438  A25C        :GL090  LDX     #LINENO-DTAB    ; LAST LINE + 10
943A  A90A                LDA     #10
943C  20049D              JSR     DADDS

943F  A4AB                LDY     XTEMP           ; RESTORE Y.
9441  60                  RTS


9442                      PROC
                  ;
                  ; RENFND -- FIND LINE FOR 'RENUMBER'
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X       = DTAB OFFSET TO LINE NUMBER
                  ;       'BLOW'  = ADDRESS OF FIRST LINE TO RENUMBER
                  ;       'BHIGH' = ADDRESS PAST LAST
                  ;
                  ;       JSR     RENFND
                  ;       A       = 0 VALID
                  ;                 1 LINE OVERLAPS A NON-RENUMBERED ONE (ERROR)
                  ;
                  ;       PP = ADDRESS OF LINE (OR SUCCESSOR)
                  ;

9442  205D94      RENFND  JSR     LNFIND          ; FIND ADDRESS.
9445  D010 ^9457          BNE     :RFD80          ; NO OVERLAP.

9447  A24E                LDX     #PP-DTAB        ; >= 'BLOW'?
9449  A013                LDY     #BLOW-DTAB
944B  20159C              JSR     DCMPI
944E  900A ^945A          BCC     :RFD90          ; NO -- ERROR.

                  ; *S*   LDX     #PP-DTAB
9450  A015                LDY     #BHIGH-DTAB     ; < 'BHIGH'?
9452  20159C              JSR     DCMPI
9455  B003 ^945A          BCS     :RFD90          ; NO ERROR.


9457  A900        :RFD80  LDA     #0              ; CLEAR A FOR EXIT
9459  60                  RTS

945A  A901        :RFD90  LDA     #1              ; SET A FOR ERROR.
945C  60                  RTS


945D                      PROC
                  ;
                  ; LNFIND -- FIND LINE NUMBER
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X  = OFFSET TO DTAB LINE NUMBER
                  ;
                  ;       JSR LNFIND
                  ;       BNE NOT FOUND (PP POINTS TO SUCCESSOR)
                  ;
                  ;       PP = ADDRESS OF LINE (OR SUCCESSOR)
                  ;
                  ; USES LINENO
                  ;
945D  B580        LNFIND  LDA     DTAB,X          ; INVERT LINE NUMBER FOR SEARCH
945F  85DD                STA     LINENO+1
9461  B581                LDA     DTAB+1,X
9463  85DC                STA     LINENO
9465  20ED7A              JSR     NUMNAM          ; SETUP 'LINENO' FOR SEARCH.
9468  4C5B99              JMP     IFIND           ; FIND LINE (OP SUCCESSOR).


946B                      PROC
                  ; CHKLN -- CHECK STATEMENT LINE # FOR OUT OF RANGE.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = DTAB INDEX TO LINE NUMBER.
                  ;
                  ;       JSR     CHKLN
                  ;       BCS     OUT OF RANGE (A = ERROR CODE)
                  ;
946B  A027        CHKLN   LDY     # HIGH [MAXLN+1]
946D  A910                LDA     # LOW [MAXLN+1]
946F  200F9C              JSR     DCWCI
9472  9002 ^9476          BCC     :CL090          ; NOT OUT OF RANGE.

9474  A98D                LDA     #LNOERR

9476  60          :CL090  RTS


9477                      PROC
                  ;
                  ; NMOVI -- MOVE VALUE FROM 'NMSBF'
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = DTAB OFFSET TO DESTINATION
                  ;       Y = 'NMSBF' OFFSET
                  ;
                  ;       JSR NMOVI
                  ;
                  ;       DTAB(X) = NMSBF+Y,+Y+1
                  ;
9477  B95305      NMOVI   LDA     NMSBF,Y
947A  9580                STA     DTAB,X
947C  B95405              LDA     NMSBF+1,Y
947F  9581                STA     DTAB+1,X
9481  60                  RTS

                  ;
                  ; I/O SUBSYTEM ROUTINES
                  ;


9482                      PROC
                  ;
                  ; CHOT -- PRINT ONE CHARACTER TO "E:".
                  ;
                  ;       A = ATASCII CHARACTER
                  ;       'CDEST' = I/O ROUTINE OFFSET OR $80 + XX OR $FF
                  ;
                  ;       JSR     CHOT
                  ;
9482  86A1        CHOT    STX     TEMP            ; SAVE REGISTERS.
9484  84A2                STY     TEMP+1

9486  AE3005              LDX     CDEST           ; PREPARE TO OUTPUT TO DEVICE.
9489  300E ^9499          BMI     :CH100          ; SPECIAL OUTPUT.

948B  20B797              JSR     IOHAND

                  ; *** EXTERNAL ENTRY POINT ***

948E  C000        IOERCK  CPY     #0              ; ERROR CHECK.
9490  101A ^94AC          BPL     :CH120          ; O.K.

                  ; *** EXTERNAL ENTRY POINT ***

9492  84E4        IOE010  STY     IOSTAT          ; SAVE I/O STATUS.
9494  A986                LDA     #IOERR
9496  4C3A7A              JMP     PSTOP           ; STOP ON ERROR.

9499  E0FF        :CH100  CPX     #$FF            ; RESULT TO 'TEXBUF'?
949B  F005 ^94A2          BEQ     :CH110          ; YES.

949D  A230                LDX     #IOCB3          ; NO -- TO IOCB 3.
949F  4C6397              JMP     DIO005          ; OUTPUT CHARACTER AND RETURN

94A2  A48F        :CH110  LDY     TELN+3          ; GET INDEX.
94A4  C0FE                CPY     #TEXLNG         ; BUFFER FULL?
94A6  F004 ^94AC          BEQ     :CH120          ; YES -- STORE NO MORE.

94A8  918C                STA     (TELN),Y        ; NO -- STORE CHARACTER.
94AA  E68F                INC     TELN+3

94AC  A4A2        :CH120  LDY     TEMP+1          ; RESTORE REGISTERS.
94AE  A6A1                LDX     TEMP
94B0  60                  RTS

94B1                      PROC
                  ;
                  ; GETLIN -- GET LINE FROR "E:"
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET TO BUFFER ADDRESS.
                  ;
                  ;       JSR     GETLIN
                  ;
                  ;       DTAB(X+2) = 0 -- START INDEX.
                  ;       DTAB(X+3) = LINE LENGTH -- END INDEX.
                  ;

94B1  86A3        GETLIN  STX     TEMP+2          ; SAVE INDICES.
94B3  84A4                STY     TEMP+3

94B5  A900                LDA     #0              ; ENABLE TEXT CURSOR.
94B7  9582                STA     DTAB+2,X        ; AS ADVERTISED.
94B9  20A79F              JSR     CRSNOP          ; MAKE CURSOR SHOW NOW.

94BC  B580                LDA     DTAB,X          ; SETUP BUFFER ADDRESS.
94BE  8D4403              STA     IOCB0+ICBAL
94C1  B581                LDA     DTAB+1,X
94C3  8D4503              STA     IOCB0+ICBAH

94C6  A905                LDA     #GETR           ; GET RECORD COMMAND.
94C8  8D4203              STA     IOCB0+ICCOM

94CB  A979        :GL010  LDA     #LINLNG-1       ; SETUP MAXIMUM LINE LENGTH FOR READ.
94CD  8D4803              STA     IOCB0+ICBLL

94D0  A200                LDX     #IOCB0          ; IOCB0.
94D2  8E4903              STX     IOCB0+ICBLH     ; *S*.
94D5  2056E4              JSR     CIO             ; DO I/O.

94D8  C089                CPY     #$89            ; TRUNCATED RECORD?
94DA  D008 ^94E4          BNE     :GL020          ; NO.

94DC  A90F                LDA     #OLLERR         ; YES -- INFORM OPERATOR & TRY AGAIN
94DE  20FFB4              JSR     MESSOT
94E1  4CCB94              JMP     :GL010

94E4  98          :GL020  TYA                     ; ERROR CHECK
94E5  30AB ^9492          BMI     IOE010          ; ERROR.

94E7  20A79F              JSR     CRSNOP          ; DISABLE TEXT CURSOR (A <> 0).

94EA  A6A3                LDX     TEMP+2          ; RESTORE INDICES.
94EC  A4A4                LDY     TEMP+3
94EE  AD4803              LDA     IOCB0+ICBLL     ; SETUP END INDEX.
94F1  9583                STA     DTAB+3,X
94F3  60                  RTS


94F4                      PROC
                  ;
                  ; TXOPEN -- OPEN THE TEXT SCREEN.
                  ;
94F4  A200        TXOPEN  LDX     #0              ; RESET GRAPHICS MODE FLAG.
94F6  8E1405              STX     GRFLAG
94F9  8E5105              STX     LETTRSZ         ; SMALL LETTERS.
94FC  8E4F05              STX     TRTLON          ; VISIBLE TURTLE OFF.
94FF  200CA6              JSR     TRONOF

9502  202996              JSR     COMPRS          ; COMPRESS MEMORY.
9505  A220                LDX     #IOCB2          ; CLOSE 'S'.
9507  203F97              JSR     DCLOSE
950A  208E96              JSR     EOPEN           ; OPEN 'E'.
950D  4C5C96              JMP     EXPAND          ; EXPAND MEMORY & RETURN.

9510                      PROC
                  ;
                  ; GSOPEN -- OPEN THE GRAPHICS SCREEN
                  ;
                  ; THIS ROUTINE COMPRESSES MEMORY, OPENS THE GRAPHICS SCREEN AND DE-COMPRESSES
                  ; THE MEMORY AGAIN.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'GSMODE' = SCREEN MODE NUMBER.
                  ;       'SPLTSC' = SPLIT SCREEN OPTION SELECT.
                  ;       'FINEFG' = FINE SCROLLING FLAG.
                  ;
                  ;       JSR GSOPEN
                  ;
                  ;       'XC' & 'YC' = SCREEN CENTER.
                  ;       'S2L'&'S2H' = VAR LIMITS.
                  ;       'APPMHI'    = TOP OF VARIABLES.
                  ;       'TRTLON'    = 1 OR 0.
                  ;       'THETA'     = 0.
                  ;       'GX' & 'GY' = 0.
                  ;
9510  202996      GSOPEN  JSR     COMPRS          ; COMPRESS MEMORY.

                  ; NOW ATTEMPT TO OPEN 'S:' TO THE DESIRED SCREEN MODE; THERE MAY
                  ; ENOUGH MEMORY # HOWEVER.

9513  A220        :GO010  LDX     #IOCB2
9515  203F97              JSR     DCLOSE

9518  A953                LDA     #'S'            ; DEVICE NAME = 'S'.
951A  8D2005              STA     OPNBUF
951D  A99B                LDA     #EOL
951F  8D2105              STA     OPNBUF+1
9522  A90C                LDA     #OWRIT+OREAD    ; SCREEN OPTIONS.
9524  0D5205              ORA     SPLTSC
9527  AE3705              LDX     GSMODE          ; IF NO MODE CHANGE ...
952A  E457                CPX     DINDEX
952C  D002 ^9530          BNE     :GO012

952E  0920                ORA     #NOCLR          ; ... THEN DON'T CLEAR SCREEN.

9530  8D6A03      :GO012  STA     IOCB2+ICAUX1
9533  8E6B03              STX     IOCB2+ICAUX2
9536  A903                LDA     #OPEN           ; OPEN COMMAND.
9538  8D6203              STA     IOCB2+ICCOM

953B  A220                LDX     #IOCB2          ; OPEN DEVICE ON IOCB2.
953D  208C97              JSR     BUFPNT          ; SETUP OPEN BUFFER POINT.
9540  2056E4              JSR     CIO
9543  84E4                STY     IOSTAT          ; SAVE STATUS FOR LATER.
9545  1003 ^954A          BPL     :GO013
9547  4C1196              JMP     :GO020          ; ERROR -- DON'T PLOT POINT.

954A  CEF002      :GO013  DEC     CRSINH          ; INHIBIT THE CURSOR.

954D  AD3705              LDA     GSMODE          ; SETUP MODE DEPENDENT VARIABLES
9550  0A                  ASL     A               ; X2
9551  AA                  TAX
9552  BD16B8              LDA     XCENTR,X
9555  8D6105              STA     XC
9558  BD17B8              LDA     XCENTR+1,X
955B  8D6205              STA     XC+1
955E  BD36B8              LDA     YCENTR,X
9561  8D6305              STA     YC
9564  BD37B8              LDA     YCENTR+1,X
9567  8D6405              STA     YC+1

956A  BD56B8              LDA     COLMAX,X        ; SET 'FLOOD' LIMITS.
956D  8DAC05              STA     MAXCOL
9570  BD57B8              LDA     COLMAX+1,X
9573  8DAD05              STA     MAXCOL+1
9576  BD76B8              LDA     ROWMAX,X
9579  8DAB05              STA     MAXROW

957C  AE3705              LDX     GSMODE
957F  BD06B8              LDA     COLRS,X         ; # OF FOREGROUND COLORS.
9582  8DB905              STA     NCOLRS
9585  E003                CPX     #2+1            ; SEE IF MODES 1 OR 2.
9587  B022 ^95AB          BCS     :GO015          ; NO -- MODE 3-15

9589  BD96B8              LDA     LMRGTB,X        ; SET MARGINS FOR LARGE LETTERS.
958C  8DB505              STA     LFCOL
958F  BD99B8              LDA     RMRGTB,X
9592  8DB605              STA     RGCOL
9595  18                  CLC
9596  ADAB05              LDA     MAXROW
9599  6902                ADC     #2              ; SET 'BOTSCR' FOR 'VPOS'.
959B  8DBF02              STA     BOTSCR
959E  A900                LDA     #KOFF           ; SET TURTLE OFF.
95A0  8D4F05              STA     TRTLON
95A3  A916                LDA     #SPUTC-IOVBAS   ; ROUTE OUTPUTS TO S*.
95A5  8D3005              STA     CDEST
95A8  4C1196              JMP     :GO020          ; AVOID TURTLE SETUP.

95AB  AD6A03      :GO015  LDA     IOCB2+ICAUX1    ; WAS SCREEN CLEARED?
95AE  2920                AND     #NOCLR
95B0  F013 ^95C5          BEQ     :GO017          ; YES.

95B2  ADB905              LDA     NCOLRS          ; NO -- RE-ESTABLISH COLOR REGS.
95B5  48          :GO016  PHA

95B6  AA                  TAX
95B7  BDBB05              LDA     PNCLRS,X
95BA  20F7A4              JSR     SETCLR
95BD  68                  PLA
95BE  38                  SEC
95BF  E901                SBC     #1
95C1  10F2 ^95B5          BPL     :GO016

95C3  3016 ^95DB          BMI     :GO018          ; (BRA).


95C5  2075AF      :GO017  JSR     DFCLRS          ; SET DEFAULT COLORS FOR MODE.
95C8  A906                LDA     #EPUTC-IOVBAS   ; ROUTE OUTPUTS TO E:.
95CA  8D3005              STA     CDEST
95CD  A900                LDA     #0              ; CLEAR WALL SELECTION.
95CF  8DCD05              STA     WALLS
95D2  8DCE05              STA     WALLS+1
95D5  8D1305              STA     PEN             ; SET PEN TO ERASE & DOWN.
95D8  8D5105              STA     LETTRSZ         ; LETTER SIZE = SMALL.

95DB  A901        :GO018  LDA     #KON            ; SET TURTLE ON.
95DD  8D4F05              STA     TRTLON

95E0  20B7A3              JSR     GHOME           ; TURTLE HOME.
95E3  20CDA3              JSR     GNORTH          ; TURTLE NORTH.
95E6  AD5205              LDA     SPLTSC          ; SPLIT SCREEN MODE?
95E9  F026 ^9611          BEQ     :GO020          ; NO -- FULL SCREEN.

95EB  A9E7                LDA     # LOW GRDLI     ; SETUP PILOT'S DLI VECTOR.
95ED  8D0002              STA     VDSLST
95F0  A9B4                LDA     # HIGH GRDLI
95F2  8D0102              STA     VDSLST+1

95F5  A9C0                LDA     #$C0            ; ENABLE VBLANK 8, DLI.
95F7  8D0ED4              STA     NMIEN

95FA  AE3705              LDX     GSMODE          ; GET MODE DEPENDENT OFFSET FROM START ...
95FD  BDD0B8              LDA     DLIOFF,X        ; ... OF DISPLAY LIST TO LCC OF DLI.
9600  A8                  TAY
9601  AD3002              LDA     SDLSTL
9604  85A1                STA     TEMP
9606  AD3102              LDA     SDLSTL+1
9609  85A2                STA     TEMP+1
960B  B1A1                LDA     (TEMP),Y        ; SET THE DLI BIT.
960D  0980                ORA     #SB
960F  91A1                STA     (TEMP),Y

9611  200CA6      :GO020  JSR     TRONOF          ; ENABLE OR DISABLE VISIBLE TURTLE.
9614  205C96              JSR     EXPAND          ; EXPAND MEMORY.

9617  A4E4                LDY     IOSTAT          ; SEE IF THERE WAS AN I/O ERROR.
9619  1008 ^9623          BPL     :GO090          ; NO.

961B  A220                LDX     #IOCB2          ; YES -- CLOSE DEVICE & REPORT ERROR.
961D  203F97              JSR     DCLOSE
9620  4C9294              JMP     IOE010

9623  A901        :GO090  LDA     #1
9625  8D1405              STA     GRFLAG          ; SET GRAPHICS SCREEN FLAG.
9628  60                  RTS

9629                      PROC
                  ; FIRST COMPRESS THE RAM STORAGE, LEAVING THE FREE AREA AT THE HIGH ADDRESSES
                  ; BY REMOVING THE GAP BETWEEN THE PROGRAM STORAGE AREA AND THE STRING
                  ; STORAGE AREA.

9629  A5B0        COMPRS  LDA     S1H             ; 'MDP' = 'S1H' (DESTINATION).
962B  85D8                STA     MDP
962D  A5B1                LDA     S1H+1
962F  85D9                STA     MDP+1

9631  A5B2                LDA     S2L             ; 'MSP' = 'S2L' (SOURCE).
9633  85D6                STA     MSP
9635  A5B3                LDA     S2L+1
9637  85D7                STA     MSP+1

9639  38                  SEC                     ; 'MBC' = 'S2H' - 'S2L' (BYTE COUNT).
963A  A5B4                LDA     S2H             ; ('CETEMP' = SAME).
963C  E5B2                SBC     S2L
963E  85DA                STA     MBC
9640  8DB305              STA     CETEMP          ; (SAVE FOR LATER).
9643  A5B5                LDA     S2H+1
9645  E5B3                SBC     S2L+1
9647  85DB                STA     MBC+1
9649  8DB405              STA     CETEMP+1

964C  18                  CLC                     ; 'APPMHI' = 'S1H' + 'MBC'.
964D  A5B0                LDA     S1H
964F  65DA                ADC     MBC
9651  850E                STA     APPMHI
9653  A5B1                LDA     S1H+1
9655  65DB                ADC     MBC+1
9657  850F                STA     APPMHI+1

9659  4CA69B              JMP     MOVIA           ; MOVE STRING STORAGE DOWN & RETURN.

965C                      PROC
                  ; NOW MOVE THE STRING STORAGE AREA UP TO THE CURRENT TOP OF MEMORY SO
                  ; THAT THE FREE AREA IS ONCE AGAIN BETWEEN THE PROGRAM STORAGE AREA AND
                  ; THE STRING STORAGE AREA.

965C  ADB305      EXPAND  LDA     CETEMP          ; 'MBC' = PRIOR 'MBC' (BYTE COUNT).
965F  85DA                STA     MBC
9661  ADB405              LDA     CETEMP+1
9664  85DB                STA     MBC+1

9666  A5B0                LDA     S1H             ; 'MSP' = 'S1H' (SOURCE).
9668  85D6                STA     MSP
966A  A5B1                LDA     S1H+1
966C  85D7                STA     MSP+1

966E  38                  SEC                     ; 'MDP' = 'MEMHI' - 'MBC' (DESTINATION).
966F  ADE502              LDA     MEMHI
9672  85B4                STA     S2H             ; 'S2H' = 'MEMHI'.
9674  E5DA                SBC     MBC

9676  85D8                STA     MDP
9678  85B2                STA     S2L             ; S2L' = SAME AS NEW 'MDP'.

967A  ADE602              LDA     MEMHI+1         ; NOW AS ABOVE FOR MSB.
967D  85B5                STA     S2H+1
967F  E5DB                SBC     MBC+1
9681  85D9                STA     MDP+1
9683  85B3                STA     S2L+1

9685  A900                LDA     #0              ; ALLOWS RESET IN ANY MODE.
9687  850E                STA     APPMHI
9689  850F                STA     APPMHI+1

968B  4CCA9B              JMP     MOVDA           ; MOVE STRING STORAGE TO TOP OF MEM & RETURN.


968E                      PROC
                  ;
                  ; EOPEN -- OPEN IOCB 0 TO E:
                  ;

968E  A200        EOPEN   LDX     #IOCB0
9690  203F97              JSR     DCLOSE

9693  ADB205              LDA     FINEFG
9696  8D6E02              STA     FINE

9699  A906                LDA     #EPUTC-IOVBAS
969B  8D3005              STA     CDEST

969E  A945                LDA     #'E'
96A0  8D2005              STA     OPNBUF
96A3  A99B                LDA     #EOL
96A5  8D2105              STA     OPNBUF+1
96A8  A90C                LDA     #OREAD+OWRIT
96AA  20F496              JSR     DOPEN

96AD  A552                LDA     LMARGN
96AF  8DB505              STA     LFCOL
96B2  A553                LDA     RMARGN
96B4  8DB605              STA     RGCOL
96B7  CEF002              DEC     CRSINH
96BA  60                  RTS

96BB                      PROC
                  ;
                  ; TSTMOD -- TEST SCREEN MODE
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       GRFLAG  = 0 FOR TEXT, ELSE GRAPHICS.
                  ;       SPLTSC  = 0 FOR FULL SCREEN, ELSE SPLIT.
                  ;       LETTRS  = 0 FOR SMALL, ELSE MEDIUM OR LARGE.
                  ;
                  ;       JSR     TSTMOD
                  ;
                  ;       A = 1 IF TEXT SCREEN, SMALL LETTERS.
                  ;           2 IF TEXT SCREEN, MEDIUM OR LARGE LETTERS.
                  ;           4 IF GRAPHICS SCREEN, WITH TEXT WINDOW (SPLIT).
                  ;           8 IF FULL GRAPHICS SCREEN.


96BB  AD1405      TSTMOD  LDA     GRFLAG          ; GRAPHICS MODE?
96BE  D00B ^96CB          BNE     :TM030          ; YES.

96C0  AD5105              LDA     LETTRSZ         ; NO -- CHECK FOR LETTER SIZE
96C3  D003 ^96C8          BNE     :TM020          ; NOT SMALL.

96C5  A901                LDA     #TXSL           ; SMALL.
96C7  60                  RTS

96C8  A902        :TM020  LDA     #TXML           ; MEDIUM OR LARGE.
96CA  60                  RTS

96CB  AD5205      :TM030  LDA     SPLTSC          ; SPLIT SCREEN GRAPHICS?
96CE  F003 ^96D3          BEQ     :TM040          ; NO -- FULL.

96D0  A904                LDA     #GRSS           ; YES -- SPLIT SCREEN.
96D2  60                  RTS

96D3  A908        :TM040  LDA     #GRFS           ; FULL SCREEN GRAPHICS.
96D5  60                  RTS

96D6                      PROC
                  ;
                  ; DNAME -- EXTRACT DEVICE/FILENAME
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       Y = INDEX TO START OF NAME
                  ;
                  ;       JSR     DNAME
                  ;
                  ;       Y = INDEX TO NAME DELIMITER.
                  ;       X = 'OPNBUF' INDEX TO CHAR AFTER NAME (EOL).
                  ;       'OPNBUF' RECEIVES NAME.
                  ;
96D6  20139F      DNAME   JSR     SLB             ; SKIP LEADING BLANKS.
96D9  4CDC96              JMP     FNAME           ; NAME TO 'OPNBUF' & RETURN.


96DC                      PROC
96DC  A200        FNAME   LDX     #0

96DE  B180        :FN010  LDA     (INLN),Y
96E0  20ED9E              JSR     CHKSEP          ; SEPARATOR?
96E3  F009 ^96EE          BEQ     :FN020          ; YES -- DONE.

96E5  9D2005              STA     OPNBUF,X        ; NO -- PART OF NAME.
96E8  E8                  INX

96E9  C8                  INY
96EA  E00F                CPX     #DNSIZE         ; NAME TOO LONG?

96EC  D0F0 ^96DE          BNE     :FN010          ; NO -- KEEP SCANNING.

96EE  A99B        :FN020  LDA     #EOL            ; APPEND EOL AFTER NAME.
96F0  9D2005              STA     OPNBUF,X
96F3  60                  RTS

96F4                      PROC
                  ;
                  ; DOPEN -- DEVICE OPEN
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'IOEDIS' <> 0 INDICATES TO IGNORE I/O ERROR.
                  ;       X = IOCB INDEX.
                  ;       A = OPEN DIRECTION + AUX1 OPTIONS.
                  ;       'OPNBUF' CONTAINS DEVICE/FILENAME.
                  ;
                  ;       JSR     DOPEN
                  ;
                  ; RETURNS ONLY IF OPEN SUCCEEDED.
                  ;
96F4  48          DOPEN   PHA                     ; SAVE OPEN CODE.
96F5  203F97              JSR     DCLOSE          ; *** JUST IN CASE ***
96F8  68                  PLA                     ; RESTORE OPEN CODE.
96F9  86A1                STX     TEMP
96FB  84A2                STY     TEMP+1
96FD  0D1D05              ORA     AUX1            ; MERGE USER BYTE.
9700  9D4A03              STA     ICAUX1,X        ; SETUP OPEN DIRECTION.

9703  20B798              JSR     CHKDEV          ; CHECK FOR INVALID OPEN.

9706  AD1E05              LDA     AUX2            ; SETUP AUX2.
9709  9D4B03              STA     ICAUX2,X

970C  A900                LDA     #0
970E  9D4803              STA     ICBLL,X         ; SETUP FOR ACCUMULATOR XFER OF DATA.
9711  9D4903              STA     ICBLH,X
9714  8D1D05              STA     AUX1            ; CLEAR USER BYTES.
9717  8D1E05              STA     AUX2

971A  A903                LDA     #OPEN           ; OPEN COMMAND.
971C  9D4203              STA     ICCOM,X

971F  208C97              JSR     BUFPNT          ; SETUP OPEN BUFFER POINTER.

9722  2056E4              JSR     CIO
                  ;       JSR     COLORS          ; RE-ESTABLISH SPECIAL COLORS.
                  ;                               ; *** NEEDED ONLY IF OUTPUT TO S: OR E: ALLOWED
                  ;                               ;     IN GRAPHICS MODE ***

9725  98                  TYA                     ; CHECK STATUS.
9726  1026 ^974E          BPL     DOP010          ; O.K.

                  ; *** EXTERNAL ENTRY POINT ***

                  ;
                  ; X = IOCB INDEX.
                  ; Y = ERROR STATUS ON ENTRY.

9728  AD0405      DOP005  LDA     IOEDIS          ; ERROR STOP DISABLED?
972B  08                  PHP
972C  A99B                LDA     #EOL            ; (RETURN EOL CHAR ON ERROR).
972E  28                  PLP
972F  F008 ^9739          BEQ     :DO007          ; NO.

9731  A5FF                LDA     RUN             ; YES -- IS IT ALSO RUN MODE?
9733  08                  PHP
9734  A99B                LDA     #EOL            ; RETURN EOL ON ERROR.
9736  28                  PLP
9737  D015 ^974E          BNE     DOP010          ; YES.

9739  203F97      :DO007  JSR     DCLOSE          ; NO -- CLOSE FILE IN ERROR.
973C  4C9294              JMP     IOE010          ; ERROR -- STOP (SKIP BRANCH POINT).


973F                      PROC
                  ;
                  ; DCLOSE -- CLOSE IOCB
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = IOCB INDEX
                  ;
                  ;       JSR     DCLOSE
                  ;
                  ; NOTE: CLOSE STATUS IS OF NO IMPORTANCE TO THIS ROUTINE.
                  ;
973F  86A1        DCLOSE  STX     TEMP
9741  84A2                STY     TEMP+1
9743  A90C                LDA     #CLOSE
9745  9D4203              STA     ICCOM,X

9748  2056E4              JSR     CIO
974B  20B49F              JSR     AUDCLR          ; CLEAR AUDIO REGISTERS.

                  ; *** EXTERNAL ENTRY POINT ***

974E              DOP010
974E  A6A1        DIO010  LDX     TEMP            ; RESTORE REGISTERS.
9750  A4A2                LDY     TEMP+1
9752  60                  RTS


9753                      PROC
                  ;
                  ; DIN & DOUT -- IOCB DATA IN AND OUT
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'IOEDIS' <> 0 INDICATES TO IGNORE I/O ERROR.
                  ;       X = IOCB INDEX
                  ;       A = DATA ('DOUT' ONLY)
                  ;
                  ;       JSR DIN/DOUT
                  ;
                  ;       A = DATA ('DIN' ONLY), RETURNS EOL ON ERROR.
                  ;
9753  48          DIN     PHA
9754  A907                LDA     #GETC           ; SETUP COMMAND BYTE.
9756  D003 ^975B          BNE     :IO003          ; (BRA).

9758  48          DOUT    PHA                     ; SAVE DATA BYTE.
9759  A90B                LDA     #PUTC           ; SETUP COMMAND BYTE.

975B  9D4203      :IO003  STA     ICCOM,X
975E  68                  PLA
975F  86A1                STX     TEMP            ; SAVE REGISTERS.
9761  84A2                STY     TEMP+1

                  ; *** EXTERNAL ENTRY POINT FROM 'CHOT' ***

9763  2056E4      DIO005  JSR     CIO

9766  84E4                STY     IOSTAT          ; SAVE I/O STATUS.
9768  C000                CPY     #0              ; CHECK STATUS.
976A  10E2 ^974E          BPL     DIO010          ; O.K.

976C  A99B                LDA     #EOL            ; RETURN EOL ON ERROR.
976E  C088                CPY     #$88            ; END OF FILE?
9770  D0B6 ^9728          BNE     DOP005          ; NO -- FATAL ERROR (SKIP BRANCH).

9772  F0DA ^974E          BEQ     DIO010          ; YES -- RETURN EOL (BRA).

9774                      PROC
                  ;
                  ; KIN -- KEYBOARD CHARACTER INPUT
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       JSR     KIN
                  ;
                  ;       A =     ATASCII CHAR
                  ;
9774  86A1        KIN     STX     TEMP            ; SAME REGISTERS.
9776  84A2                STY     TEMP+1
9778  A224                LDX     #KGETC-IOVBAS   ; GET CHAR FROM 'K'.
977A  20B797              JSR     IOHAND
977D  4C8E94              JMP     IOERCK          ; CHECK FOR ERROR & RETURN.

9780                      PROC
                  ;
                  ; TOUT -- GRAPHICS DATA OUTPUT
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       A = ONE GRAPHICS PIXEL
                  ;
                  ;       JSR     TOUT
                  ;
9780  86A1        TOUT    STX     TEMP            ; SAVE REGISTERS.
9782  84A2                STY     TEMP+1
9784  A216                LDX     #SPUTC-IOVBAS   ; PUT CHARACTER TO 'S:'
9786  20B797              JSR     IOHAND
9789  4C8E94              JMP     IOERCK          ; CHECK FOR ERROR & RETURN.


978C                      PROC

978C  A920        BUFPNT  LDA     # LOW OPNBUF    ; POINT TO NAME BUFFER FOR OPEN.
978E  9D4403              STA     ICBAL,X
9791  A905                LDA     # HIGH OPNBUF
9793  9D4503              STA     ICBAH,X
9796  60                  RTS

9797                      PROC
                  ;
                  ; PRTSTG -- PRINT TEXT DATA
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET TO TEXT DATA POINTER.
                  ;
                  ;       JSR     PRTSTG
                  ;
9797  84AA        PRTSTG  STY     TEMP2+3
9799  B580                LDA     DTAB,X          ; MOVE POINTER.
979B  85A7                STA     TEMP2
979D  B581                LDA     DTAB+1,X
979F  85A8                STA     TEMP2+1
97A1  B583                LDA     DTAB+3,X        ; ENDING INDEX.
97A3  85A9                STA     TEMP2+2
97A5  B482                LDY     DTAB+2,X        ; STARTING INDEX.

97A7  C4A9        :PR010  CPY     TEMP2+2         ; COMPARE START INDEX WITH END
97A9  F009 ^97B4          BEQ     :PR080          ; EQUAL -- DONE.

97AB  B1A7                LDA     (TEMP2),Y       ; GET NEXT CHARACTER.
97AD  C8                  INY
97AE  208294              JSR     CHOT            ; PRINT CHARACTER.
97B1  4CA797              JMP     :PR010

97B4  A4AA        :PR080  LDY     TEMP2+3
97B6  60                  RTS


97B7                      PROC
                  ;
                  ; IOHAND -- DIRECT I/O TO INTERFACE ROUTINE
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = I/O ROUTINE OFFSET TO ADDRESS TABLE ENTRY (SYSTEM)
                  ;
                  ;       JSR     IOHAND
                  ;
                  ;       CLOBBERS Y REGISTER.
                  ;
97B7  A8          IOHAND  TAY                     ; SAVE REGISTER A.
97B8  BD01E4              LDA     IOVBAS+1,X      ; GET ADDRESS MSB.
97BB  48                  PHA
97BC  BD00E4              LDA     IOVBAS+0,X      ; GET ADDRESS USB.
97BF  48                  PHA
97C0  98                  TYA                     ; RESTORE REGISTER A.
97C1  60                  RTS                     ; (JMP) TO HANDLER.


97C2                      PROC
                  ;
                  ; SFNAME -- GET DEVICE NAME AND STORE IN 'OPNBUF'.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'EXEC = 0 FOR SCAN MODE, ELSE EXECUTE.
                  ;       'XXXX' = INPUT LINE INDEX.
                  ;       X = INDEX TO EOL IN 'OPNBUF'.
                  ;
                  ;       JSR     SFNAME
                  ;       BNE     ERROR (A = ERROR CODE).
                  ;
                  ;       'OPNBUF' = DEVICE NAME.
                  ;       Y = INPUT LINE INDEX TO FIELD AFTER DEVICE/FILENAME.
                  ;
97C2  206E81      SFNAME  JSR     ATOM            ; GET DEVICE/FILENAME
97C5  D00A ^97D1          BNE     :SF090          ; ERROR.

97C7  C920                CMP     #TEXT           ; TEXT LITERAL?
97C9  F007 ^97D2          BEQ     :SF100          ; YES.

97CB  2918                AND     #SVAR+USVAR     ; STRING NAME?
97CD  D00C ^97DB          BNE     :SF200          ; YES.

97CF  A902                LDA     #IMPERR         ; NO -- ERROR.

97D1  60          :SF090  RTS                     ; RETURN WITH CC SET.

                  ; SCAN TEXT LITERAL DATA TO EXTRACT DEVICE/FILENAME.

97D2  20DC96      :SF100  JSR     FNAME           ; NAME TO 'OPNBUF'.
97D5  8C4805              STY     XXXX            ; SAVE LINE INDEX.
97D8  A900                LDA     #0              ; SET CC FOR NORMAL EXIT.
97DA  60                  RTS                     ; RETURN WITH CC SET.

                  ; DEVICE/FILENAME IS A STRING VARIABLE VALUE

97DB  A592        :SF200  LDA     EXEC            ; EXECUTE MODE?
97DD  F0F2 ^97D1          BEQ     :SF090          ; NO -- DONE.

97DF  8C4805              STY     XXXX
97E2  A200                LDX     #0
97E4  A4C4                LDY     DP+2

97E6  C4C5        :SF220  CPY     DP+3            ; DONE?
97E8  F00B ^97F5          BEQ     :SF250          ; YES.

97EA  B1C2                LDA     (DP),Y          ; NO -- MOVE NAME.
97EC  9D2005              STA     OPNBUF,X
97EF  C8                  INY
97F0  E8                  INX
97F1  E00F                CPX     #DNSIZE         ; OVERLENGTH NAME?
97F3  D0F1 ^97E6          BNE     :SF220          ; O.K. SO FAR.

97F5  A99B        :SF250  LDA     #EOL
97F7  9D2005              STA     OPNBUF,X

97FA  A900                LDA     #0              ; SET CC FOR NORMAL EXIT.
97FC  60                  RTS                     ; RETURN WITH CC SET.


97FD                      PROC
                  ;
                  ; SCNDEV -- GET DEVICE NAME AND SETUP FOR 'READ:', 'WRITE:' OR 'CLOSE:'
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'EXEC' = 0 FOR SCAN MODE, ELSE EXECUTE.
                  ;       Y = INPUT LINE INDEX.
                  ;       A = AUX1 OPEN CODE. (0 = CLOSE, ELSE OPEN).
                  ;
97FD  85E0        SCNDEV  STA     LEND            ; SAVE DEVICE OPEN CODE.
97FF  20C297              JSR     SFNAME          ; EXTRACT FILENAME.
9802  D034 ^9838          BNE     :SC290          ; ERROR.

9804  A592                LDA     EXEC            ; EXECUTE MODE?
9806  F030 ^9838          BEQ     :SC290          ; NO -- ALL DONE.

9808  A900                LDA     #0
980A  85E4                STA     IOSTAT          ; CLEAR I/O STATUS.
980C  85C0                STA     NP+2

980E  86C1                STX     NP+3
9810  A920                LDA     # LOW OPNBUF
9812  85BE                STA     NP
9814  A905                LDA     # HIGH OPNBUF
9816  85BF                STA     NP+1

9818  20AD9E              JSR     SETSVL          ; SETUP TO ACCESS STRING VARIABLE LIST.
981B  A920                LDA     #ATRIO          ; 'I/O' ATTRIBUTE.
981D  8D6605              STA     ATRTYP
9820  20CE98              JSR     SFIND           ; SEE IF STRING EXIS:T.
9823  D014 ^9839          BNE     :SC300          ; NO.


9825  A4C4                LDY     DP+2            ; YES -- GET IOCB INDEX FROM VALUE.
9827  B1C2                LDA     (DP),Y
9829  48                  PHA
982A  A5E0                LDA     LEND              ; LOOK AT "OPEN" CODE.
982C  D003 ^9831          BNE     :SC270          ; NORMAL IN OR OUT.

982E  20EC98              JSR     SDELET          ; 'DONE' -- DELETE NAME.

9831  68          :SC270  PLA
9832  AA                  TAX
9833  AC4805              LDY     XXXX
9836  A900                LDA     #0              ; SET CC FOR NORMAL EXIT.

9838  60          :SC290  RTS                     ; RETURN WITH CC SET.

                  ; FIRST ACCESS TO DEVICE, DO IMPLICIT OPEN.

9839  20B798      :SC300  JSR     CHKDEV          ; CHECK FOR VALID DEVICE.

983C  A5E0                LDA     LEND              ; CHECK "OPEN" CODE.
983E  D006 ^9846          BNE     :SC310          ; NORMAL IN OR OUT.

9840  AC4805              LDY     XXXX            ; RESTORE INDEX.
9843  A902                LDA     #IMPERR         ; 'DONE' -- CLOSING NON-OPEN FILE.
9845  60                  RTS

9846  207098      :SC310  JSR     FNDIOB          ; FIND A FREE IOCB, IF AVAILABLE.
9849  D024 ^986F          BNE     :SC900          ; NONE AVAILABLE.

984B  A5E0                LDA     LEND              ; GET AUX1 OPEN CODE.
984D  20F496              JSR     DOPEN           ; OPEN DEVICE.

9850  86DE                STX     LS              ; SAVE IOCB # ASSOCIATED WITH DEVICE.
9852  8EF002              STX     CRSINH          ; INHIBIT CURSOR JUST IN CASE.

9855  A9DE                LDA     # LOW LS
9857  85C2                STA     DP
9859  A900                LDA     # HIGH LS
985B  85C3                STA     DP+1
985D  A900                LDA     #0
985F  85C4                STA     DP+2
9861  A901                LDA     #1
9863  85C5                STA     DP+3

9865  200599              JSR     SINSRT          ; INSERT NAMED STRING CONTAINING INFO.
9868  08                  PHP
9869  A6DE                LDX     LS
986B  AC4805              LDY     XXXX
986E  28                  PLP

986F  60          :SC900  RTS                     ; RETURN WITH CC SET.



9870                      PROC
                  ;
                  ; FNDIOB -- FIND A FREE IOCB
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       JSR     FNDIOB
                  ;       BNE     NO FREE IOCB (A = ERROR CODE)
                  ;
                  ;       X = = IOCB INDEX.
                  ;
9870  A240        FNDIOB  LDX     #IOCB4          ; START WITH IOCB #4.

9872  BD4003      :FD010  LDA     ICHID,X         ; TEST FOR CURRENTLY UNUSED.
9875  C9FF                CMP     #$FF
9877  F007 ^9880          BEQ     :FD090          ; FOUND ONE.

9879  208C98              JSR     NXTIOB          ; BUMP INDEX TO NEXT IOCB.
987C  D0F4 ^9872          BNE     :FD010          ; MORE TO CHECK.

987E  A996                LDA     #FILERR         ; NONE AVAILABLE.

9880  60          :FD090  RTS                     ; RETURN WITH CC SET.


9881                      PROC
                  ;
                  ; CLOSEM -- CLOSE IOCBS 3 THROUGH 7 (WHETHER OPEN OR NOT).
                  ;
9881  A230        CLOSEM  LDX     #IOCB3          ; START WITH IOCB #3.

9883  203F97      :CL010  JSR     DCLOSE          ; CLOSE THE IOCB.
9886  208C98              JSR     NXTIOB          ; BUMP INDEX TO NEXT IOCB.
9889  D0F8 ^9883          BNE     :CL010          ; MORE TO DO.

988B  60                  RTS


988C                      PROC
                  ;
                  ; NXTIOB -- BUMP INDEX TO NEXT IOCB.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = IOCB INDEX
                  ;
                  ;       JSR     NXTIOB
                  ;       BEQ     INDEX PAST IOCB #7
                  ;
                  ;       X = IOCB INDEX TO NEXT IOCB
                  ;
988C  8A          NXTIOB  TXA
988D  18                  CLC
988E  6910                ADC     #IOCBSZ
9890  AA                  TAX
9891  E080                CPX     #IOCB7+IOCBSZ

9893              RDV090
9893              CKD090
9893  60                  RTS                     ; RETURN WITH CC SET.


9894                      PROC
                  ;
                  ; REMDEV -- REMOVE DEVICE ASSIGNMENTS FROM STRING LIST
                  ;
9894  A252        :RD000  LDX     #MEMA-DTAB      ; REMOVE STRING VAR FROM LIST.
9896  A03A                LDY     #LP-DTAB
9898  20459A              JSR     DMOVI

989B  203E9B              JSR     MDEALL

989E  20AD9E      REMDEV  JSR     SETSVL          ; SETUP TO SCAN STRING VARIABLES ...
98A1  A23A                LDX     #LP-DTAB        ; ... TO REMOVE ALL DEVICE ASSIGNMENTS.

98A3  20139A      :RD010  JSR     SEND            ; END OF LIST?
98A6  F0EB ^9893          BEQ     RDV090          ; YES.

98A8  A23A                LDX     #LP-DTAB        ; CHECK ATTRIBUTE.
98AA  20869A              JSR     SATTR

98AD  C920                CMP     #ATRIO
98AF  F0E3 ^9894          BEQ     :RD000          ; YES -- REMOVE IT FROM LIST.

98B1  20AA9A              JSR     SNXTI           ; GO TO NEXT ITEM IN LTST.
98B4  4CA398              JMP     :RD010


98B7                      PROC
                  ; CHKDEV -- CHECK FOR VALID DEVICE

98B7  20BB96      CHKDEV  JSR     TSTMOD          ; CHECK SCREEN MODE.
98BA  C901                CMP     #TXSL           ; TEXT, SMALL LETTERS?
98BC  F0D5 ^9893          BEQ     CKD090          ; YES -- NO RESTRICTIONS.

98BE  AD2005              LDA     OPNBUF          ; CHECK FOR 'E' OR 'S'.
98C1  C945                CMP     #'E'
98C3  F004 ^98C9          BEQ     :CK010          ; INVALID -- CLOBBERS SCREEN.

98C5  C953                CMP     #'S'
98C7  D0CA ^9893          BNE     CKD090

98C9  A985        :CK010  LDA     #SCNERR
98CB  4C3A7A              JMP     PSTOP

                  ;
                  ; THIS PACKAGE HAS THREE LEVELS OF STRING HANDLING ROUTINES:
                  ;
                  ;       NAMED STRING HANDLING -- SFIND, SDELET & SINSRT
                  ;
                  ;       TEXT DATA HANDLING -- SCORP
                  ;
                  ;       IMPLEMENTATION UTILITIES -- IFIND, SEND, PSETUP, PROVE, ICOMP
                  ;                                   ILENG,  SNXTI, IMATCH & IALLOC
                  ;


                  ;
                  ; NAMED STRING HANDLING
                  ;
                  ; THESE ROUTINES USE THE FOLLOWING VARIABLES
                  ;
                  ;       NP = POINTER TO STRING NAME.
                  ;       DP = POINTER TO STRING DATA PORTION.
                  ;       LP = POINTER TO START OF LIST OF NAMED STRINGS (S1L OR S2L).
                  ;


98CE                      PROC
                  ;
                  ; SFIND -- FIND NAMED STRING IN LIST
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       LP POINTS TO START OF LIST OF NAMED STRINGS
                  ;       NP POINTS TO NAME TO FIND IN LIST
                  ;       ATRTYP  SET
                  ;
                  ;       JSR     SFIND
                  ;       BNE     NAME NOT IN LIST OR NAME IS NULL
                  ;
                  ;       DP POINTS TO DATA PORTION OF NAMED STRING FOUND IN LIST
                  ;
98CE  205B99      SFIND   JSR     IFIND           ; FIND NAME IN LIST.
98D1  D018 ^98EB          BNE     :SF080          ; NOT FOUND.

98D3  A242                LDX     #DP-DTAB        ; SET 'DP' TO POINT TO DATA PORTION.
98D5  A04E                LDY     #PP-DTAB
98D7  20459A              JSR     DMOVI

98DA  A5D1                LDA     PP+3            ; SKIP OVER NAME PORTION.
98DC  20089D              JSR     DADDP

98DF  A901                LDA     #1              ; SET START INDEX.
98E1  85C4                STA     DP+2

98E3  A000                LDY     #0              ; SET END INDEX.
98E5  18                  CLC
98E6  71C2                ADC     (DP),Y
98E8  85C5                STA     DP+3

98EA  98                  TYA                     ; SET CC FOR EXIT.

98EB  60          :SF080  RTS                     ; RETURN WITH CC SET.

98EC                      PROC
                  ;
                  ; SDELET -- DELETE NAMED STRING FROM LIST
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       NP POINTS TO STRING NAME
                  ;       LP POINTS TO START OF LIST OF NAMED STRNGS
                  ;       ATRTYP SET
                  ;
                  ;       JSR SDELET
                  ;       BNE NAMED STRING NOT FOUND OR NAME IS NULL
                  ;
98EC  205B99      SDELET  JSR     IFIND           ; FIND STRING IN LIST.
98EF  D013 ^9904          BNE     :SD090          ; NAMED STRING NOT FOUND.

                  ; * * * EXTERNAL ENTRY POINT ***

98F1  A252        SDEL2   LDX     #MEMA-DTAB      ; MEMA = PP (FOR DEALLOCATE CALL).
98F3  A04E                LDY     #PP-DTAB
98F5  20459A              JSR     DMOVI

98F8  203E9B              JSR     MDEALL          ; DELETE STRING.

98FB  A24E                LDX     #PP-DTAB        ; PP = MEMA.
98FD  A052                LDY     #MEMA-DTAB
98FF  20459A              JSR     DMOVI

9902  A900                LDA     #0              ; SET CC FOR NORMAL EXIT.
9904  60          :SD090  RTS                     ; RETURN WITH CC SET.


9905                      PROC
                  ;
                  ; SINSRT -- NAMED STRING INSERT
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       NP POINTS TO STRING NAME
                  ;       DP POINTS TO STRING DATA PORTION
                  ;       LP POINTS TO START OF NAMED STRING LIST
                  ;       ATRTYP SET
                  ;       TKNTYP, TKNOFF SET IF NUMBERED STATEMENT.
                  ;
                  ;       JSR     SINSRT
                  ;       BNE     NAME IS NULL, OR NO ROOM FOR STRING IN LIST
                  ;
                  ;       ATRTYP  STORED IF 'VARIABLE'
                  ;       TKNTYP, TKNOFF  STORED IF NUMBERED STATEMENT.
                  ;
9905  205B99      SINSRT  JSR     IFIND           ; IS NAME ALREADY IN LIST?
9908  D003 ^990D          BNE     :SI020          ; NO.

990A  20F198              JSR     SDEL2           ; YES -- DELETE OLD OCCURRENCE.

990D  A900        :SI020  LDA     #0              ; CALCULATE ALLOCATION SIZE.
990F  85D4                STA     MEMB
9911  85D5                STA     MEMB+1

9913  A254                LDX     #MEMB-DTAB      ; STRING SIZE = NAME SIZE ...
9915  38                  SEC

9916  A5C1                LDA     NP+3
9918  E5C0                SBC     NP+2
991A  20089D              JSR     DADDP

991D  38                  SEC                     ; ... + DATA PORTION SIZE ...
991E  A5C5                LDA     DP+3
9920  E5C4                SBC     DP+2
9922  20089D              JSR     DADDP

9925  A906                LDA     #6              ; ... + 6 BYTES OF OVERHEAD.
                                                  ; 2 = BLOCK SIZE; 1 = NAME SIZE,
                                                  ; 1 = DATA SIZE; 2 = 'EXTRA' AT END.
9927  20089D              JSR     DADDP

992A  A252                LDX     #MEMA-DTAB      ; ALLOCATE ADDRESS FROM 'IFIND' CALL IN PP.

992C  A04E                LDY     #PP-DTAB
992E  20459A              JSR     DMOVI

9931  20C19A              JSR     MALLOC          ; ALLOCATE SPACE IN LIST.
9934  D01E ^9954          BNE     :SI090          ; NOT ENOUGH ROOM.

9936  A23E                LDX     #NP-DTAB        ; MOVE NAME TO NEW STRING ...
9938  A002                LDY     #2              ; ... STARTING AFTER ALLOCATION SIZE.
993A  20509A              JSR     SMOVI

993D  A242                LDX     #DP-DTAB        ; NOW MOVE DATA PORTION.
993F  20509A              JSR     SMOVI

                  ; 'MEMA' = ADDRESS OF 'ATTRIBUTE' DESTINATION.
                  ; Y = 0.

9942  AD6605              LDA     ATRTYP
9945  D009 ^9950          BNE     :SI060          ; 'VARIABLE' ATTRIBUTE.

9947  AD6805              LDA     TKNTYP          ; TOKENIZE LINE.
994A  91D2                STA     (MEMA),Y
994C  C8                  INY
994D  AD6A05              LDA     TKNOFF          ; OFFSET.

9950  91D2        :SI060  STA     (MEMA),Y
9952  A900                LDA     #0              ; SET CC FOR NORMAL EXIT.
9954  60          :SI090  RTS                     ; RETURN WITH CC SET.


                  ; TEXT DATA UTILITIES
                  ;
                  ; THESE ROUTINES USE THE FOLLOWING VARIABLES:
                  ;
                  ;       DP = POINTER TO TEXT DATA
                  ;       MP = POINTER TO TEXT PATTERN DATA
                  ;       AP1 = AUXILLIARY POINTER TO TEXT SUB-STRING
                  ;       AP2 = AUXILLIARY POINTER TO TEXT SUB-STRING


9955                      PROC
                  ;
                  ; SCOMP -- COMPARE TWO TEXT STRINGS
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       DP POINTS TO DATA TEXT
                  ;       MP POINTS TO DATA TEXT
                  ;
                  ;       JSR     SCOMP
                  ;       BEQ     DATA TEXTS ARE IDENTICAL
                  ;       BCS     DP TEXT >= MP TEXT
                  ;       BCC     DP TEXT < MP TEXT
                  ;
                  ; NOTE: THE COMPARISON IS BASED UPON THE STANDARD ATASCII COLLATION
                  ;       SEQUENCE: WHEN ONE TEXT IS A SUBSET OF THE FIRST PART OF THE
                  ;       OTHER TEXT, THE SHORTER ONE IS CONSIDERED TO BE < THE LONGER ONE.
                  ;
9955  202D9A      SCOMP   JSR     PSETUP          ; DP TO SP, MP TO PP.

9958  4CA999              JMP     ICOMP           ; COMPARE TEXT & RETURN WITH CC SET.

                  ;
                  ; GENERAL STRING IMPLEMENTATION UTILITIES
                  ;
                  ; THESE ROUTINES USE THE FOLLOWING VARIABLES:
                  ;
                  ; SP = SOURCE TEXT POINTER
                  ; PP = PATTERN TEXT POINTER


995B                      PROC
                  ;
                  ; IFIND -- FIND NAMED STRING IN LIST
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       NP POINTS TO DESIRED NAME
                  ;       LP POINTS TO START OF NAMED STRING LIST
                  ;       ATRTYP  ATTRIBUTE
                  ;
                  ;       JSR     IFIND
                  ;       BNE     NOT FOUND  (PP POINTS TO SUCCESSOR)
                  ;
                  ;       PP POINTS TO NAMED STRING IN LIST
                  ;
                  ;       IF NOT FOUND. THE SUCCESSOR IS CHOSEN SO THAT:
                  ;
                  ;       STATEMENTS ARE KEPT IN LINE # ORDER.
                  ;       VARIABLES ARE APPENDED TO THE END OF THE LIST.
                  ;
995B  A5C0        IFIND   LDA     NP+2            ; NAME NULL?
995D  C5C1                CMP     NP+3
995F  F045 ^99A6          BEQ     :IF080          ; YES -- DONE.

9961  A24A                LDX     #SP-DTAB        ; SP = NP.
9963  A03E                LDY     #NP-DTAB
9965  203B9A              JSR     PMOVE

9968  A24E                LDX     #PP-DTAB        ; PP = LP.
996A  A03A                LDY     #LP-DTAB
996C  203B9A              JSR     PMOVE

996F              :IF020
996F  A24E                LDX     #PP-DTAB
9971  20139A              JSR     SEND            ; END OF LIST?
9974  F030 ^99A6          BEQ     :IF080          ; YES -- DONE.

9976  A903                LDA     #3              ; NO -- SETUP START INDEX ...
9978  85D0                STA     PP+2
997A  18                  CLC                     ; ... & END INDEX (TO NAME)
997B  A002                LDY     #2
997D  71CE                ADC     (PP),Y
997F  85D1                STA     PP+3

9981  20A999              JSR     ICOMP           ; NAME COMPARISON.
9984  F009 ^998F          BEQ     :IF030          ; A MATCH.
9986  B016 ^999E          BCS     :IF040          ; NOT THERE YET (IF LINE).
                                                  ; NOT A MATCH (IF VARIABLE).
9988  AD6605              LDA     ATRTYP          ; LINE INSERTION?
998B  D011 ^999E          BNE     :IF040          ; NO -- SEARCH TO END.
998D  9017 ^99A6          BCC     :IF080          ; YES -- PAST CORRECT SPOT (BRA).

                  ; CHECK IF ATTRIBUTE MATCHES.

998F  AD6605      :IF030  LDA     ATRTYP          ; ATTRIBUTE TO MATCH.
9992  F014 ^99A8          BEQ     :IF090          ; 'LINE' -- FOUND IT!

9994  A24E                LDX     #PP-DTAB        ; CHECK ATTRIBUTE.
9996  20869A              JSR     SATTR
9999  CD6605              CMP     ATRTYP
999C  F00A ^99A8          BEQ     :IF090          ; ATTRIBUTE MATCHED!

999E  A24E        :IF040  LDX     #PP-DTAB        ; SKIP TO NEXT LIST ENTRY.
99A0  20AA9A              JSR     SNXTI

99A3  4C6F99              JMP     :IF020          ; TRY AGAIN.

99A6  A9FF        :IF080  LDA     #$FF            ; SET CC FOR EXIT (NOT FOUND).

99A8  60          :IF090  RTS                     ; RETURN WITH CC SET.



99A9                      PROC
                  ;
                  ; ICOMP -- COMPARE TEXT DATA
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       SP POINTS TO DATA TEXT
                  ;       PP POINTS TO DATA TEXT
                  ;
                  ;       JSR     ICOMP
                  ;       BEQ     DATA TEXTS ARE IDENTICAL
                  ;       BCS     SP DATA >= PP DATA
                  ;       BCC     SP DATA < PP DATA
                  ;

99A9  201F9A      ICOMP   JSR     ILENG           ; SEE IF EQUAL LENGTHS.
99AC  F03C ^99EA          BEQ     IMATCH          ; YES -- COMPARE & RETURN.

99AE  B01D ^99CD          BCS     :IC050          ; PP DATA SHORTER THAN SP DATA.

99B0  A5D1                LDA     PP+3            ; SAVE STARTING VALUE.
99B2  85A7                STA     TEMP2
99B4  38                  SEC                     ; (CLEAR BORROW).
99B5  A5CD                LDA     SP+3            ; ADJUST PP DATA LENGTH FOR COMPARISON.
99B7  E5CC                SBC     SP+2
99B9  18                  CLC
99BA  65D0                ADC     PP+2
99BC  85D1                STA     PP+3

99BE  20EA99              JSR     IMATCH          ; NOW COMPARE.
99C1  08                  PHP
99C2  A5A7                LDA     TEMP2           ; RESTORE ALTERED PARAMETER.
99C4  85D1                STA     PP+3
99C6  28                  PLP
99C7  D020 ^99E9          BNE     :IC090          ; NOT EQUAL -- CC SET FOR EXIT.

99C9  A9FF                LDA     #$FF            ; SET CC FOR EXIT.
99CB  18                  CLC
99CC  60                  RTS                     ; RETURN WITH CC SET.

99CD  A5CD        :IC050  LDA     SP+3            ; SAVE STARTING VALUE.
99CF  85A7                STA     TEMP2
99D1  18                  CLC
99D2  A5CC                LDA     SP+2            ; ADJUST SP LENGTH FOR COMPARISON.
99D4  65D1                ADC     PP+3
99D6  38                  SEC
99D7  E5D0                SBC     PP+2
99D9  85CD                STA     SP+3

99DB  20EA99              JSR     IMATCH          ; NOW COMPARE.
99DE  08                  PHP
99DF  A5A7                LDA     TEMP2           ; RESTORE ALTERED PARAMETER.
99E1  85CD                STA     SP+3
99E3  28                  PLP
99E4  D003 ^99E9          BNE     :IC090          ; NOT EQUAL -- CC SET FOR EXIT.

99E6  A9FF                LDA     #$FF            ; SET CC FOR EXIT.
99E8  38                  SEC
99E9  60          :IC090  RTS                     ; RETURN WITH CC SET.

99EA                      PROC
                  ;
                  ; IMATCH -- MATCH TWO TEXT DATA STRINGS
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       SP = SOURCE DATA TEXT (SOURCE DATA MUST BE LONGER THAN PATTERN)
                  ;       PP = PATTERN DATA TEXT
                  ;
                  ;       JSR     IMATCH
                  ;       BEQ     PATTERN IS CONTAINED WITHIN SOURCE
                  ;       BCS     SOURCE COLLATES >= PATTERN
                  ;       BCC     SOURCE COLLATES < PATTERN
                  ;
99EA  A5CC        IMATCH  LDA     SP+2            ; SAVE STARTING INDICES.
99EC  85A1                STA     TEMP
99EE  A5D0                LDA     PP+2
99F0  85A2                STA     TEMP+1

99F2  A4D0        :IM010  LDY     PP+2            ; SEE IF ALL OF PATTERN HAS MATCHED.
99F4  C4D1                CPY     PP+3
99F6  F010 ^9A08          BEQ     :IM090          ; YES -- ALL DONE.

99F8  A4CC                LDY     SP+2            ; NO -- COMPARE ANOTHER BYTE.
99FA  B1CA                LDA     (SP),Y
99FC  E6CC                INC     SP+2
99FE  A4D0                LDY     PP+2
9A00  D1CE                CMP     (PP),Y
9A02  D004 ^9A08          BNE     :IM090          ; NO COMPARE -- CC SET FOR EXIT.

9A04  E6D0                INC     PP+2
9A06  B0EA ^99F2          BCS     :IM010          ; (BRA).

9A08  08          :IM090  PHP                     ; SAVE CC.
9A09  A5A1                LDA     TEMP            ; RESTORE STARTING INDICES.
9A0B  85CC                STA     SP+2
9A0D  A5A2                LDA     TEMP+1
9A0F  85D0                STA     PP+2
9A11  28                  PLP                     ; RESTORE CC.

9A12              SEN090
9A12  60                  RTS                     ; RETURN WITH CC SET.

9A13                      PROC
                  ;
                  ; SEND -- CHECK FOR END OF STRING LIST
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = DTAB OFFSET TO LIST POINTER
                  ;
                  ;       JSR     SEND
                  ;       BEQ     END OF LIST REACHED
                  ;
                  ;       Y IS ALTERED
                  ;
9A13  A030        SEND    LDY     #S1H-DTAB       ; SEE IF END OF REGION #1.
9A15  20159C              JSR     DCMPI
9A18  F0F8 ^9A12          BEQ     SEN090          ; YES.

9A1A  A034                LDY     #S2H-DTAB       ; SEE IF END OF REGION #2 ...
9A1C  4C159C              JMP     DCMPI           ; ... & RETURN WITH CC SET.


9A1F                      PROC
                  ;
                  ; ILENG -- COMPARE LENGTHS OF SOURCE TEXT AND PATTERN TEXT
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       SP POINTS TO SOURCE DATA TEXT
                  ;       PP POINTS TO PATTERN DATA TEXT
                  ;
                  ;       JSR     ILENG
                  ;       BEQ     DATA TEXTS ARE EQUAL LENGTH
                  ;       BCS     SOURCE TEXT >= PATTERN TEXT
                  ;       BCC     SOURCE TEXT < PATTERN TEXT
                  ;
9A1F  A5D1        ILENG   LDA     PP+3
9A21  38                  SEC
9A22  E5D0                SBC     PP+2
9A24  85A1                STA     TEMP

9A26  A5CD                LDA     SP+3
9A28  E5CC                SBC     SP+2

9A2A  E5A1                SBC     TEMP            ; CC = SP LENGTH = PP LENGTH.
9A2C  60                  RTS



9A2D                      PROC
                  ;
                  ; PSETUP -- MOVE POINTERS (DP TO SP, MP TO PP)
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       JSR     PSETUP
                  ;
                  ;       SP = DP
                  ;       PP = MP
                  ;

9A2D  A24A        PSETUP  LDX     #SP-DTAB        ; SP = DP.
9A2F  A042                LDY     #DP-DTAB
9A31  203B9A              JSR     PMOVE

9A34  A24E                LDX     #PP-DTAB        ; PP = MP.
9A36  A046                LDY     #MP-DTAB
9A38  4C3B9A              JMP     PMOVE           ; AND RETURN.


9A3B                      PROC
                  ;
                  ; PMOVE -- MOVE STRING/DATA TEXT POINTERS
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = DTAB OFFSET
                  ;       Y = DTAB OFFSET
                  ;
                  ;       JSR     PMOVE
                  ;
                  ;       DTAB(X) = DTAB(Y) (4 BYTE MOVE)
                  ;
9A3B  B98200      PMOVE   LDA     DTAB+2,Y
9A3E  9582                STA     DTAB+2,X

9A40  B98300              LDA     DTAB+3,Y
9A43  9583                STA     DTAB+3,X

                  ; ** EXTERNAL ENTRY POINT ***

9A45  B98000      DMOVI   LDA     DTAB,Y
9A48  9580                STA     DTAB,X

9A4A  B98100              LDA     DTAB+1,Y
9A4D  9581                STA     DTAB+1,X
9A4F  60                  RTS


      = 0000              IF      FALSE
                          PROC
                  ;
                  ; IALLOC -- ALLOCATE MEMORY
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       A = # OF BYTES TO ALLOCATE
                  ;
                  ;       JSR     IALLOC
                  ;       BNE     NOT ENGUGH ROOM
                  ;
                  ;       DP POINTS TO NEW ALLOCATION + 2 (START OF STRING)
                  ;
   -              IALLCC  STA     MEMB            ; SETUP MEMB = A BYTES ...
   -                      LDA     #0
   -                      STA     MEMB+1

   -                      LDA     #3              ; ... + 3
   -                      LDX     #MEMB-DTAB
   -                      JSR     DADDS

   -                      LDX     #MEMA-DTAB      ; SETUP MEMA = ALLOCATION ADDRESS.
   -                      LDY     #S2L-DTAB
   -                      JSR     DMOVI

   -                      JSR     MALLOC          ; ALLOCATE MEMORY.
   -                      BNE     :IA090          ; NOT ENOUGH ROOM.

   -                      LDX     #DP-DTAB        ; DP = ADDRESS OF STRING STORAGE AREA.
   -                      LDY     #MEMA-DTAB
   -                      JSR     DMOVI

   -                      LDA     #2
   -                      JSR     DADDS

   -                      LDA     #1              ; SET STARTING & ENDING INDICES.
   -                      STA     DP+2
   -                      STA     DP+3
   -                      LDA     #0              ; SET CC FOR EXIT.

   -              :IA090  RTS                     ; RETURN WITH CC SET.
                          ENDIF


9A50                      PROC
                  ;
                  ; SMOVI -- MOVE TEXT DATA TO MEMA (FORMING STRING)
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = DTAB INDEX TO STRING POINTER
                  ;       Y = MEMA OFFSET TO START STORING
                  ;
                  ;       JSR     SMOVI
                  ;
                  ;       MEMA = LAST LOCATION STORED INTO + 1
                  ;       Y = 0
                  ;

9A50  B580        SMOVI   LDA     DTAB,X          ; MOVE SOURCE POINTER TO TEMP.
9A52  85A1                STA     TEMP
9A54  B581                LDA     DTAB+1,X
9A56  85A2                STA     TEMP+1
9A58  B582                LDA     DTAB+2,X
9A5A  85A3                STA     TEMP+2
9A5C  B583                LDA     DTAB+3,X
9A5E  85A4                STA     TEMP+3

9A60  38                  SEC                     ; CALCULATE STRING LENGTH ...
9A61  A5A4                LDA     TEMP+3
9A63  E5A3                SBC     TEMP+2

9A65  91D2        :SM010  STA     (MEMA),Y        ; ... & STORE IN TARGET AREA.
9A67  C8                  INY
9A68  84A5                STY     TEMP+4          ; SAVE INDEX.

9A6A  A4A3                LDY     TEMP+2          ; DONE?
9A6C  C4A4                CPY     TEMP+3
9A6E  F008 ^9A78          BEQ     :SM090          ; YES.

9A70  B1A1                LDA     (TEMP),Y        ; NO -- MOVE A BYTE.
9A72  E6A3                INC     TEMP+2

9A74  A4A5                LDY     TEMP+4          ; GET TARGET INDEX.
9A76  D0ED ^9A65          BNE     :SM010          ; (BRA).

9A78  A900        :SM090  LDA     #0              ; PREPARE FOR D.P. ADDITION.
9A7A  85A6                STA     TEMP+5
9A7C  A252                LDX     #MEMA-DTAB      ; PREPARE TO BUMP MEMA.
9A7E  A025                LDY     #TEMP+4-DTAB
9A80  20329C              JSR     DADDI
9A83  A000                LDY     #0              ; AS PROMISED.
9A85  60                  RTS

9A86                      PROC
                  ;
                  ; SATTR -- POINT TO ATTRIBUTE BYTE
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X    = DATA OFFSET TO STRING POINTER
                  ;
                  ;       JSR SATTR
                  ;
                  ;       A    = ATTRIBUTE VALUE
                  ;       TEMP = ADDRESS OF ATTRIBUTE BYTE
                  ;       Y    = 0
                  ;
9A86  B581        SATTR   LDA     DTAB+1,X        ; MOVE POINTER TO TEMP.
9A88  85A2                STA     TEMP+1
9A8A  B580                LDA     DTAB,X
9A8C  85A1                STA     TEMP

9A8E  A000                LDY     #0              ; ADDRESS ...
9A90  18                  CLC                     ; ...+ LENGTH.
9A91  71A1                ADC     (TEMP),Y
9A93  48                  PHA                     ; LSB

9A94  C8                  INY
9A95  A5A2                LDA     TEMP+1
9A97  71A1                ADC     (TEMP),Y
9A99  85A2                STA     TEMP+1          ; MSB


9A9B  68                  PLA
9A9C  38                  SEC                     ; ... -2.
9A9D  E902                SBC     #2
9A9F  85A1                STA     TEMP
9AA1  B002 ^9AA5          BCS     :SA010
9AA3  C6A2                DEC     TEMP+1          ; (BORROW).

9AA5  A000        :SA010  LDY     #0
9AA7  B1A1                LDA     (TEMP),Y        ; AS ADVERTISED.
9AA9  60                  RTS


9AAA                      PROC
                  ;
                  ; SNXTI -- POINT TO NEXT STRING IN LIST
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = DATA OFFSET TO STRING LIST POINTER
                  ;
                  ;       JSR SNXTI
                  ;
                  ;       DTAB(X) = POINTER TO NEXT STRING IN LIST
                  ;
9AAA  B581        SNXTI   LDA     DTAB+1,X        ; MOVE STRING POINTER TO TEMP.
9AAC  85A2                STA     TEMP+1
9AAE  B580                LDA     DTAB,X
9AB0  85A1                STA     TEMP

9AB2  A000                LDY     #0              ; ADD ADDRESS TO ...
9AB4  18                  CLC
9AB5  71A1                ADC     (TEMP),Y        ; ... ALLOCATION LENGTH ...
9AB7  9580                STA     DTAB,X          ; ... TO GET NEXT ADDRESS.

9AB9  C8                  INY
9ABA  A5A2                LDA     TEMP+1
9ABC  71A1                ADC     (TEMP),Y
9ABE  9581                STA     DTAB+1,X
9AC0  60                  RTS


9AC1                      PROC
                  ;
                  ; MALLOC -- MEMORY ALLOCATE
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'MEMA' CONTAINS THE ADDRESS OF THE START OF ALLOCATION
                  ;          REGION #1: DATA AT START ADDRESS AND ABOVE ARE MOVED UP.
                  ;          REGION #2: DATA BELOW START ADDRESS ARE MOVED DOWN.
                  ;       'MEMB' CONTAINS THE NUMBER OF BYTES TO ALLOCATE
                  ;
                  ;       JSR     MALLOC
                  ;       BNE     NOT ENOUGH MEMORY TO SATISFY ALLOCATION
                  ;
                  ;       'MEMA' CONTAINS LOWEST ADDRESS IN THE ALLOCATED BLOCK
                  ;       FIRST TWO BYTES OF ALLOCATED BLOCK = BLOCK SIZE
                  ;
9AC1  A030        MALLOC  LDY     #S1H-DTAB       ; ACC = S1H ...
9AC3  20A29D              JSR     DLOADA

9AC6  A054                LDY     #MEMB-DTAB      ; ... + MEMB.
9AC8  20AC9D              JSR     DADDA

9ACB  A032                LDY     #S2L-DTAB       ; COMPARE ACC WITH S2L.
9ACD  20B69D              JSR     DCMPA
9AD0  B069 ^9B3B          BCS     :MA300          ; NOT ENOUGH ROOM.

9AD2  A252                LDX     #MEMA-DTAB      ; SEE IF ALLOCATION IN REGION #1 OR #2.
9AD4  A032                LDY     #S2L-DTAB
9AD6  20159C              JSR     DCMPI
9AD9  B028 ^9B03          BCS     :MA100          ; REGION M2.

                  ; ALLOCATE FROM REGION #1

9ADB  A256                LDX     #MSP-DTAB       ; MSP = MEMA.
9ADD  A052                LDY     #MEMA-DTAB
9ADF  20459A              JSR     DMOVI

9AE2  A258                LDX     #MDP-DTAB       ; MDP = MEM A ...
9AE4  20459A              JSR     DMOVI

9AE7  A054                LDY     #MEMB-DTAB      ; ... + MEMB.
9AE9  20329C              JSR     DADDI

9AEC  A25A                LDX     #MBC-DTAB       ; MBC = S1H ...
9AEE  A030                LDY     #S1H-DTAB
9AF0  20459A              JSR     DMOVI

9AF3  A052                LDY     #MEMA-DTAB      ; ... - MEMA.
9AF5  20429C              JSR     DSUBI

9AF8  A230                LDX     #S1H-DTAB       ; S1H = ACC (= S1H + MEMB).
9AFA  20A79D              JSR     DSTORA

9AFD  20CA9B              JSR     MOVDA

9B00  4C2E9B              JMP     :MA200

                  ; ALLOCATE IN REGION #2

9B03  A256        :MA100  LDX     #MSP-DTAB       ; MSP = S2L.
9B05  A032                LDY     #S2L-DTAB
9B07  20459A              JSR     DMOVI

9B0A  A25A                LDX     #MBC-DTAB       ; MBC = MEMA ...
9B0C  A052                LDY     #MEMA-DTAB
9B0E  20459A              JSR     DMOVI

9B11  A032                LDY     #S2L-DTAB       ; ... - S2L.
9B13  20429C              JSR     DSUBI

9B16  A232                LDX     #S2L-DTAB       ; S2L = S2L - MEMB.
9B18  A054                LDY     #MEMB-DTAB
9B1A  20429C              JSR     DSUBI

9B1D  A258                LDX     #MDP-DTAB       ; MDP = S2L (NEW VALUE).
9B1F  A032                LDY     #S2L-DTAB
9B21  20459A              JSR     DMOVI

9B24  A252                LDX     #MEMA-DTAB      ; MEMA = MEMA - MEMB.
9B26  A054                LDY     #MEMB-DTAB
9B28  20429C              JSR     DSUBI

9B2B  20A69B              JSR     MOVIA           ; MOVE DATA DOWNWARD.

                  ; COMMON CODE

9B2E  A000        :MA200  LDY     #0              ; MOVE BLOCK SIZE TO BLOCK.
9B30  A5D4                LDA     MEMB
9B32  91D2                STA     (MEMA),Y
9B34  C8                  INY

9B35  A5D5                LDA     MEMB+1
9B37  91D2                STA     (MEMA),Y
9B39  88                  DEY                     ; SET CC FOR NORMAL EXIT.
9B3A  60                  RTS
9B3B  A989        :MA300  LDA     #INSERR         ; SET CC FOR ERROR EXIT.
9B3D  60                  RTS



9B3E                      PROC
                  ;
                  ; MDEALL -- MEMORY DEALLOCATE
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'MEMA' = ADDRESS OF BLOCK TO DEALLOCATE
                  ;       FIRST 2 BYTES OF BLOCK = SIZE OF BLOCK
                  ;
                  ;       JSR     MDEALL
                  ;
                  ;       'MEMA' = ADDRESS OF BLOCK FOLLOWING DEALLOCATED BLOCK (AFTER DEALL)
                  ;
9B3E  A000        MDEALL  LDY     #0              ; GET SIZE OF BLOCK TO MEMB.
9B40  B1D2                LDA     (MEMA),Y
9B42  85D4                STA     MEMB
9B44  C8                  INY
9B45  B1D2                LDA     (MEMA),Y
9B47  85D5                STA     MEMB+1

9B49  A252                LDX     #MEMA-DTAB      ; SEE IF IN REGION #1 OR #2.
9B4B  A032                LDY     #S2L-DTAB
9B4D  20159C              JSR     DCMPI
9B50  B029 ^9B7B          BCS     :MD100          ; REGION #2.

                  ; DEALLOCATE FROM REGION #1.

9B52  A256                LDX     #MSP-DTAB       ; MSP = MEMA ...
9B54  A052                LDY     #MEMA-DTAB
9B56  20459A              JSR     DMOVI

9B59  A054                LDY     #MEMB-DTAB      ; ... + MEMB.
9B5B  20329C              JSR     DADDI

9B5E  A25A                LDX     #MBC-DTAB       ; MBC = S1H ...
9B60  A030                LDY     #S1H-DTAB
9B62  20459A              JSR     DMOVI

9B65  A056                LDY     #MSP-DTAB       ; ... - MSP.
9B67  20429C              JSR     DSUBI

9B6A  A230                LDX     #S1H-DTAB       ; S1H = S1H - MEMB.
9B6C  A054                LDY     #MEMB-DTAB
9B6E  20429C              JSR     DSUBI

9B71  A258                LDX     #MDP-DTAB       ; MDP = MEMA.

9B73  A052                LDY     #MEMA-DTAB
9B75  20459A              JSR     DMOVI

9B78  4CA69B              JMP     MOVIA           ; MOVE DATA DOWNWARD & RETURN.

                  ; DEALLOCATE MEMORY IN REGION #2

9B7B  A256        :MD100  LDX     #MSP-DTAB       ; MSP = S2L.
9B7D  A032                LDY     #S2L-DTAB
9B7F  20459A              JSR     DMOVI

9B82  A25A                LDX     #MBC-DTAB       ; MBC = MEMA ...
9B84  A052                LDY     #MEMA-DTAB
9B86  20459A              JSR     DMOVI

9B89  A032                LDY     #S2L-DTAB       ; ... - S2L.
9B8B  20429C              JSR     DSUBI

9B8E  A232                LDX     #S2L-DTAB       ; S2L = S2L + MEMB.
9B90  A054                LDY     #MEMB-DTAB
9B92  20329C              JSR     DADDI

9B95  A258                LDX     #MDP-DTAB       ; MDP = S2L (NEW VALUE).
9B97  A032                LDY     #S2L-DTAB
9B99  20459A              JSR     DMOVI

9B9C  A252                LDX     #MEMA-DTAB      ; MEMA = MEMA + MEMB.
9B9E  A054                LDY     #MEMB-DTAB
9BA0  20329C              JSR     DADDI

9BA3  4CCA9B              JMP     MOVDA           ; MOVE DATA UPWARD & RETURN

                  ;
                  ; MOVE UTILITIES FOR MEMORY MANAGEMENT
                  ;
                  ; MOVE BLOCKS OF DATA WITH EITHER INCREASING OR DECREASING ADDRESS
                  ;
                  ; THREE VARIABLES CONTROL THE MOVE ROUTINES?
                  ;
                  ; 'MSP' CONTAINS POINTER TO SOURCE DATA LOCATION
                  ; 'MDP' CONTAINS POINTER TO DESTINATION DATA LOCATION
                  ; 'MBC' CONTAINS THE NUMBER OF BYTES TO MOVE
                  ;


9BA6                      PROC
                  ;
                  ; MOVIA -- MOVE DATA BLOCK WITH INCREASING ADDRESS
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'MSP', 'MDP' & 'MBC' SETUP
                  ;
                  ;       JSR     MOVIA
                  ;
9BA6  A5DA        MOVIA   LDA     MBC             ; SEE IF BYTE COUNT = ZERO.
9BA8  AA                  TAX                     ; SAVE LSB OF BYTE COUNT.
9BA9  05DB                ORA     MBC+1
9BAB  F01C ^9BC9          BEQ     :MI090          ; ZERO -- NOTHING TO DO.

9BAD  A000                LDY     #0              ; INDEX TO DATA BLOCK.

9BAF  B1D6        :MI010  LDA     (MSP),Y         ; MOVE DATA.
9BB1  91D8                STA     (MDP),Y
9BB3  C8                  INY                     ; BUMP INDEX.
9BB4  D004 ^9BBA          BNE     :MI020          ; NO PAGE WRAP.

9BB6  E6D7                INC     MSP+1           ; PAGE WRAP -- BUMP POINTER VARIABLES.
9BB8  E6D9                INC     MDP+1

9BBA  CA          :MI020  DEX                     ; DONE?
9BBB  D004 ^9BC1          BNE     :MI030          ; NO.

9BBD  A5DB                LDA     MBC+1           ; NOT SURE -- CHECK FURTHER.
9BBF  F008 ^9BC9          BEQ     :MI090          ; YES -- DONE.

9BC1  E0FF        :MI030  CPX     #$FF            ; MAINTAIN D.P. BYTE COUNT.
9BC3  D0EA ^9BAF          BNE     :MI010

9BC5  C6DB                DEC     MBC+1           ; BORROW FROM MSB.
9BC7  B0E6 ^9BAF          BCS     :MI010          ; (BRA).

9BC9  60          :MI090  RTS


9BCA                      PROC
                  ;
                  ; MOVDA -- MOVE DATA BLOCK WITH DECREASING ADDRESS
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'MSP', 'MDP' & 'MBC' SETUP
                  ;
                  ;       JSR     MOVDA
                  ;
9BCA  A5DA        MOVDA   LDA     MBC             ; SETUP BYTE COUNT ...
9BCC  AA                  TAX
9BCD  A8                  TAY                     ; ... AND DATA INDEX.
9BCE  05DB                ORA     MBC+1           ; TEST FOR ZERO BYTE COUNT.
9BD0  F024 ^9BF6          BEQ     :MD090          ; ZERO -- NOTHING TO DO.

9BD2  18                  CLC                     ; ADJUST POINTERS FOR START.
9BD3  A5D7                LDA     MSP+1
9BD5  65DB                ADC     MBC+1
9BD7  85D7                STA     MSP+1

9BD9  18                  CLC
9BDA  A5D9                LDA     MDP+1
9BDC  65DB                ADC     MBC+1
9BDE  85D9                STA     MDP+1

9BE0  88          :MD010  DEY                     ; DECREMENT INDEX.
9BE1  C0FF                CPY     #$FF            ; WRAP?
9BE3  D006 ^9BEB          BNE     :MD020          ; NO.

9BE5  C6DB                DEC     MBC+1           ; YES -- DECREMENT ALL POINTERS (MSB)
9BE7  C6D7                DEC     MSP+1
9BE9  C6D9                DEC     MDP+1

9BEB  B1D6        :MD020  LDA     (MSP),Y         ; MOVE A DATA BYTE.
9BED  91D8                STA     (MDP),Y

9BEF  CA                  DEX                     ; DONE?
9BF0  D0EE ^9BE0          BNE     :MD010          ; NO -- CONTINUE.

9BF2  A5DB                LDA     MBC+1           ; NOT SURE -- CHECK FURTHER.
9BF4  D0EA ^9BE0          BNE     :MD010          ; NO -- CONTINUE.
9BF6  60          :MD090  RTS                     ; YES -- RETURN.


9BF7                      PROC
                  ;
                  ; MVINLN -- MOVE PART OF 'INLN' TO A FIXED ADDRESS BUFFER
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       Y = CURRENT INDEX IN 'INLN'
                  ;
                  ;       JSR :MINLN
                  ;
                  ;       'INLNBF' CONTAINS Y/Y+'INBFSZ'-1 CHARACTERS FROM 'INLN'
                  ;       LOWER CASE IS CONVERTED TO UPPER CASE.
                  ;       Y IS NOT PRESERVED.
                  ;
9BF7  A200        MVINLN  LDX     #0

9BF9  B180        :MVN10  LDA     (INLN),Y
9BFB  C961                CMP     #'A'+$20        ; LC?
9BFD  9006 ^9C05          BCC     :MVN20          ; NO.
9BFF  C97B                CMP     #'Z'+1+$20
9C01  B002 ^9C05          BCS     :MVN20          ; NO.
9C03  29DF                AND     #UC             ; YES

9C05  9D3805      :MVN20  STA     INLNBF,X
9C08  C8                  INY
9C09  E8                  INX
9C0A  E00A                CPX     #INBFSZ
9C0C  90EB ^9BF9          BCC     :MVN10

9C0E  60                  RTS

                  ; DOUBLE PRECISION ROUTINES
                  ;
                  ; ALL VARIABLES ARE ACCESSED VIA THEIR OFFSET FROM SYMBOL 'DTAB'.
                  ; NORMALLY THE X AND/OR Y REGISTERS CONTAIN THE 'DTAB' OFFSET
                  ; VALUES TO THE VARIABLE(S) TO BE DEALT WITH.
                  ;


9C0F                      PROC
                  ;
                  ; DCWCI -- DOUBLE BYTE UNSIGNED COMPARE WITH CONSTANT.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = DTAB OFFSET TO VARIABLE.
                  ;       Y = MSB OF CONSTANT.
                  ;       A = LSB OF CONSTANT.
                  ;
                  ;       JSR     DCWCI           ; UNSIGNED COMPARE.
                  ;
                  ;       CC = DTAB(X) : Y,A
                  ;
9C0F  85A7        DCWCI   STA     TEMP2           ; SAVE LSB.
9C11  84A8                STY     TEMP2+1         ; SAVE MSB.
9C13  A027                LDY     #TEMP2-DTAB
                  ; *S*   JMP     DCMPI           ; COMPARE & RETURN.



9C15                      PROC
                  ;
                  ; DCMPI -- DOUBLE BYTE UNSIGNED COMPARE INDEXED
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = DATA #1 OFFSET
                  ;       Y = DATA #2 OFFSET
                  ;
                  ;       JSR     DCMPI
                  ;       BEQ     DTAB(X) = DTAB(Y)
                  ;       BCS     BTAB(X) >= DTAB(Y)
                  ;       BCC     DTAB(X) < DTAB(Y)
                  ;
                  ; CC = DTAB(X) : DTAB(Y) (UNSIGNED)
                  ;
9C15  B581        DCMPI   LDA     DTAB+1,X        ; COMPARE MSBS.
9C17  D98100              CMP     DTAB+1,Y
9C1A  D005 ^9C21          BNE     :DC090          ; NOT EQUAL -- ALL DONE.

                  ; *** EXTERNAL ENTRY POINT **

9C1C  B580        DCM010  LDA     DTAB,X          ; EQUAL -- COMPARE LSBS.
9C1E  D98000              CMP     DTAB,Y

9C21  60          :DC090  RTS



9C22                      PROC
                  ;
                  ; DSCMI -- DOUBLE BYTE SIGNED COMPARE INDEXED
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = DATA #1 OFFSET
                  ;       Y = DATA #2 OFFSET
                  ;
                  ;       JSR     DSCMI
                  ;       BEQ     DTAB(X) = DTAB(Y)
                  ;       BCS     DTAB(X) >= DTAB(Y)
                  ;       BCC     DTAB(X) < DTAB(Y)
                  ;
9C22  B98100      DSCMI   LDA     DTAB+1,Y        ; COMPARE MSBS FIRST.
9C25  4980                EOR     #$80
9C27  85A1                STA     TEMP
9C29  B581                LDA     DTAB+1,X
9C2B  4980                EOR     #$80
9C2D  C5A1                CMP     TEMP
9C2F  F0EB ^9C1C          BEQ     DCM010          ; EQUAL -- COMPARE LSBS.

9C31  60                  RTS                     ; NOT EQUAL -- ALL DONE.


                  ;
                  ; DMOVI -- DOUBLE BYTE MOVE INDEXED
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = DESTINATION OFFSET
                  ;       Y = SOURCE OFFSET
                  ;
                  ;       JSR     DMOVI
                  ;
                  ;       DTAB(X) = DTAB(Y)
                  ;
                  ; *** SEE 'PMOVE' FOR THE 'DMOVI' CODE ***


9C32                      PROC
                  ;
                  ; DADDI -- DOUBLE PRECISION ADD
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET TO
                  ;       Y = OFFSET TO
                  ;
                  ;       JSR     DADDI
                  ;       BVS     OVERFLOW
                  ;
                  ;       DTAB(X) = DTAB(X) + DTAB(Y)
                  ;
9C32  18          DADDI   CLC

9C33  B580        DADDIX  LDA     DTAB,X
9C35  798000              ADC     DTAB,Y
9C38  9580                STA     DTAB,X

9C3A  B581                LDA     DTAB+1,X
9C3C  798100              ADC     DTAB+1,Y
9C3F  9581                STA     DTAB+1,X

9C41  60                  RTS

9C42                      PROC
                  ;
                  ; DSUBI -- DOUBLE PRECISION SUBTRACT
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET
                  ;       Y = OFFSET
                  ;
                  ;       JSR     DSUBI
                  ;       BVS     OVERFLOW
                  ;       BEQ     RESULT = 0
                  ;
                  ;       DTAB(X) = DTAB(X) - DTAB(Y)
                  ;
9C42  38          DSUBI   SEC

9C43  B580        DSUBIX  LDA     DTAB,X
9C45  F98000              SBC     DTAB,Y
9C48  9580                STA     DTAB,X

9C4A  B581                LDA     DTAB+1,X
9C4C  F98100              SBC     DTAB+1,Y
9C4F  9581                STA     DTAB+1,X

9C51  1580                ORA     DTAB,X          ; SET CC FOR ZERO TEST.

9C53  60                  RTS


9C54                      PROC
                  ;
                  ; DMULI -- DOUBLE PRECISION MULTIPLY
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET
                  ;       X = OFFSET
                  ;
                  ;       JSR     DMULI
                  ;
                  ;       DTAB(X) = DTAB(X) * DTAB(Y)
                  ;
9C54  A910        DMULI   LDA     #16             ; SETUP LOOP COUNTER.
9C56  85A3                STA     TEMP+2

9C58  A900                LDA     #0              ; INITIALIZE TEMP ACCUMULATOR.
9C5A  85A1                STA     TEMP
9C5C  85A2                STA     TEMP+1

9C5E  1680        :DM010  ASL     DTAB,X          ; DOUBLE PRECISION SHIFT LEFT.
9C60  3681                ROL     DTAB+1,X
9C62  900F ^9C73          BCC     :DM020          ; NO BIT PRESENT.

9C64  18                  CLC                     ; BIT SET -- ADD TO PARTIAL.
9C65  A5A1                LDA     TEMP
9C67  798000              ADC     DTAB,Y
9C6A  85A1                STA     TEMP
9C6C  A5A2                LDA     TEMP+1
9C6E  798100              ADC     DTAB+1,Y
9C71  85A2                STA     TEMP+1

9C73  C6A3        :DM020  DEC     TEMP+2          ; DONE?
9C75  F007 ^9C7E          BEQ     :DM090          ; YES -- RESULT IS IN 'TEMP'.

9C77  06A1                ASL     TEMP            ; NO -- DOUBLE PRECISION SHIFT LEFT.
9C79  26A2                ROL     TEMP+1
9C7B  4C5E9C              JMP     :DM010

9C7E  A5A1        :DM090  LDA     TEMP            ; DONE -- MOVE RESULT.
9C80  9580                STA     DTAB,X
9C82  A5A2                LDA     TEMP+1
9C84  9581                STA     DTAB+1,X
9C86  60                  RTS


9C87                      PROC
                  ;
                  ; DDIVI -- DOUBLE PRECISION DIVIDE
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET TO DIVIDEND
                  ;       Y = OFFSET TO DIVISOR
                  ;
                  ;       JSR     DDIVI
                  ;
                  ;       DTAB(X) = DTAB(X) / DTAB(Y) (SIGNED)
                  ;       'TEMP' = REMAINDER (SIGN MAY BE WRONG!!!)
                  ;
9C87  B98000      DDIVI   LDA     DTAB,Y          ; CHECK FOR DIVIDE BY ZERO.
9C8A  198100              ORA     DTAB+1,Y
9C8D  D005 ^9C94          BNE     :DD003          ; NO -- O.K.

9C8F  A984                LDA     #DIVERR         ; ERROR.
9C91  4C3A7A              JMP     PSTOP

9C94  A911        :DD003  LDA     #16+1           ; SETUP LOOP COUNTFR.
9C96  85A3                STA     TEMP+2
9C98  86A4                STX     TEMP+3          ; SAVE INDEX TO DIVIDEND.

9C9A  A900                LDA     #0              ; INITIALIZE REMAINDER.
9C9C  85A1                STA     TEMP
9C9E  85A2                STA     TEMP+1

9CA0  B98100              LDA     DTAB+1,Y        ; SEE IF DIVISOR IS NEGATIVE.
9CA3  85A6                STA     TEMP+5
9CA5  1006 ^9CAD          BPL     :DD006          ; NO.

9CA7  20F19C              JSR     DNEGI           ; YES -- NEGATE DIVIDEND ...
9CAA  20DD9C              JSR     :DD093          ; ... & DIVISOR (*** CRAZY CALL ***).

9CAD  B581        :DD006  LDA     DTAB+1,X        ; SEE IF DIVIDEND IS NEGATIVE.
9CAF  85A5                STA     TEMP+4
9CB1  1003 ^9CB6          BPL     :DD008          ; NO.

9CB3  20F19C              JSR     DNEGI           ; YES -- NEGATE IT NOW (& THEN AGAIN LATER).

9CB6  18          :DD008  CLC

9CB7  A6A4        :DD010  LDX     TEMP+3          ; GET INDEX TO DIVIDEND.
9CB9  3680                ROL     DTAB,X          ; DOUBLE PRECISION ROTATE.
9CBB  3681                ROL     DTAB+1,X

9CBD  C6A3                DEC     TEMP+2          ; DONE?
9CBF  F011 ^9CD2          BEQ     :DD090          ; YES.

9CC1  26A1                ROL     TEMP            ; NO.
9CC3  26A2                ROL     TEMP+1

9CC5  A221                LDX     #TEMP-DTAB      ; IS REMAINDER < DIVISOR?
9CC7  20159C              JSR     DCMPI
9CCA  90EB ^9CB7          BCC     :DD010          ; YES.

9CCC  20429C              JSR     DSUBI           ; NO.
9CCF  38                  SEC
9CD0  B0E5 ^9CB7          BCS     :DD010          ; (BRA).

9CD2  A5A5        :DD090  LDA     TEMP+4          ; SEE IF RESULT IS TO BE NEGATED.
9CD4  1003 ^9CD9          BPL     :DD092          ; NO.

9CD6  20F19C              JSR     DNEGI           ; YES -- NEGATE POSITIVE RESULT.

9CD9  A5A6        :DD092  LDA     TEMP+5          ; WAS DIVISOR NEGATED EARLIER.
9CDB  1007 ^9CE4          BPL     :DD095          ; NO.

9CDD  98          :DD093  TYA                     ; YES -- NEGATF IT BACK TO ORIGINAL SIGN.
9CDE  AA                  TAX
9CDF  20F19C              JSR     DNEGI
9CE2  A6A4                LDX     TEMP+3          ; RESTORE INDEX.

9CE4  60          :DD095  RTS


9CE5                      PROC
                  ;
                  ; DMODI -- MODULO OF SORTS
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET TO DIVIDEND
                  ;       Y = OFFSET OT DIVISOR
                  ;
                  ;       JSR     DMODI
                  ;
                  ;       DTAB(X) = DTAB(X) MOD DTAB(Y)
                  ;
9CE5  20879C      DMODI   JSR     DDIVI           ; FIRST DO DIVISION.
9CE8  A5A1                LDA     TEMP            ; TAKE ADVANTAGE OF SIDE EFFECT.
9CEA  9580                STA     DTAB,X
9CEC  A5A2                LDA     TEMP+1
9CEE  9581                STA     DTAB+1,X
9CF0  60                  RTS


9CF1                      PROC
                  ;
                  ; DNEGI -- DOUBLE PRECISION NEGATE
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET TO NUMBER
                  ;
                  ;       JSR     DNEGI
                  ;
                  ;       DTAB(X) = -DTAB(X)
                  ;
9CF1  38          DNEGI   SEC                     ; (CLEAR BORROW).
9CF2  A900                LDA     #0
9CF4  F580                SBC     DTAB,X
9CF6  9580                STA     DTAB,X

9CF8  A900                LDA     #0
9CFA  F581                SBC     DTAB+1,X
9CFC  9581                STA     DTAB+1,X
9CFE  60                  RTS


9CFF                      PROC
                  ;
                  ; DABSI -- DOUBLE PRECISION ABS FUNCTION
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ; X = OFFSET TO NUMBER
                  ;
                  ; JSR DABSI
                  ;
                  ; DTAB(X) = ABS (DTAB(X))
                  ;
9CFF  B581        DABSI   LDA     DTAB+1,X        ; CHECK SIGN OF MSB.
9D01  30EE ^9CF1          BMI     DNEGI

9D03  60                  RTS


9D04                      PROC
                  ;
                  ; DADDS -- ADD A REGISTER TO DOUBLE BYTE
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       A = SIGNED BINARY NUMBER (-126 TO 127)
                  ;       X = DTAB OFFSET TO DP NUMBER
                  ;
                  ;       JSR     DADDS
                  ;
                  ;       DTAB(X) = DTAB(X) + A
                  ;
9D04  C900        DADDS   CMP     #0              ; SEE IF POSITIVE OR NEGATIVE.
9D06  300C ^9D14          BMI     :DA030          ; NEGATIVE.

                  ; *** EXTERNAL ENTRY POINT ***

9D08  18          DADDP   CLC                     ; POSITIVE -- ADD.
9D09  7580                ADC     DTAB,X
9D0B  9580                STA     DTAB,X
9D0D  9002 ^9D11          BCC     :DA010          ; NO CARRY.

9D0F  F681                INC     DTAB+1,X        ; CARRY -- ADD TO MSB.

9D11  60          :DA010  RTS

                  ; *** EXTERNAL ENTRY FOINT ***

9D12  A9FF        DDCRI   LDA     #-1

9D14  18          :DA030  CLC
9D15  7580                ADC     DTAB,X
9D17  9580                STA     DTAB,X
9D19  B002 ^9D1D          BCS     :DA040          ; NO BORROW.

9D1B  D681                DEC     DTAB+1,X        ; BORROW -- SUB FROM MSB
9D1D  60          :DA040  RTS


9D1E                      PROC
                  ; RELATIONAL TESTS
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = DATA #1 OFFSET
                  ;       Y = DATA #2 OFFSET
                  ;
                  ;       JSR     DXXTI           ONE OF SIX ROUTINES
                  ;
                  ;       DTAB(X) = 1 IF RELATION TRUE, 0 IF FALSE

9D1E  20159C      DEQTI   JSR     DCMPI           ; UNSIGNED COMPARE (FASTER THAN SIGNED).
9D21  F027 ^9D4A          BEQ     DTRUE           ; EQUAL RESULTS IN TRUE.
9D23  D029 ^9D4E          BNE     DFALSE          ; UNEQUAL RESULTS IN FALSE.

9D25  20159C      DNETI   JSR     DCMPI           ; UNSIGNED COMPARE (FASTER THAN SIGNED).
9D28  D020 ^9D4A          BNE     DTRUE           ; UNEQUAL RESULTS IN TPUE.
9D2A  F022 ^9D4E          BEQ     DFALSE          ; EQUAL RESULTS IN FALSE.

9D2C  20229C      DGTTI   JSR     DSCMI           ; SIGNED COMPARE.
9D2F  F01D ^9D4E          BEQ     DFALSE          ; EQUAL RESULTS IN FALSE.
9D31  901B ^9D4E          BCC     DFALSE          ; LESS THAN RESULTS IN FALSE.
9D33  B015 ^9D4A          BCS     DTRUE           ; GREATER THAN RESULTS IN TRUE.

9D35  20229C      DLTTI   JSR     DSCMI           ; SIGNED COMPARE.
9D38  9010 ^9D4A          BCC     DTRUE           ; LESS THAN RESULTS IN TPUE.
9D3A  B012 ^9D4E          BCS     DFALSE          ; GREATER THAN OR EQUAL PESULTS IN FALSE

9D3C  20229C      DGETI   JSR     DSCMI           ; SIGNED COMPARE.
9D3F  B009 ^9D4A          BCS     DTRUE           ; GREATER THAN OR EQUAL RESULTS IN TRUE.
9D41  900B ^9D4E          BCC     DFALSE          ; LESS THAN RESULTS IN FALSE.

9D43  20229C      DLETI   JSR     DSCMI           ; SIGNED COMPARE.
9D46  F002 ^9D4A          BEQ     DTRUE           ; EQUAL RESULTS IN TRUE.
9D48  B004 ^9D4E          BCS     DFALSE          ; GREATER THAN RESULTS IN FALSE.
                  ; *S*   BCC     DTRUE           ; LESS THAN RESULTS IN TPUE.

9D4A  A901        DTRUE   LDA     #1              ;"TRUE" ...
9D4C  D002 ^9D50          BNE     DFA010          ; ... TO VARIABLE.

9D4E  A900        DFALSE  LDA     #0              ; "FALSE" ...

9D50  9580        DFA010  STA     DTAB,X          ; ... TO VARIABLE.

9D52  A900                LDA     #0
9D54  9581                STA     DTAB+1,X
9D56  60                  RTS


9D57                      PROC

      = 0000              IF      LOGGRP
                  ;
                  ; DLANDI -- DOUBLE PRECISION LOGICAL AND
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET
                  ;       Y = OFFSET
                  ;
                  ;       JSR     DLAND
                  ;
                  ;       DTAB(X) = DTAB(X) LOGICAL AND DTAB(Y)
                  ;
   -              DLANDI  JSR     DTXP            ; IS DTAB(X) FALSE?
   -                      BEQ     DFALSE          ; YES.

                  ; *** ENTRY FOR 'DLORI' ***

   -              DAN010  JSR     DTYP            ; IS DTAB(Y) FALSE?
   -                      BEQ     DFALSE          ; YES -- SET DTAB(X) = FALSE AND EXIT.
   -                      BNE     DTRUE           ; NO -- SET DTAB(X) = TRUE AND EXIT.

   -                      PROC
                  ; DLORI -- DOUBLE PRECISION LOGICAL OR
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET
                  ;       Y = OFFSET
                  ;
                  ;       JSR     DLORI
                  ;
                  ;       DTAB(X) = DTAB(X) LOGICAL OR DTAB(Y)
                  ;
   -              DLORI   JSR     DTXP            ; IS DTAB(X) TRUE?
   -                      BNE     DTRUE           ; YES.
   -                      BEQ     DAN010          ; NO (BRA).


                          ENDIF
9D57                      PROC
                  ;
                  ; DLNOTI -- DOUBLE PRECISION LOGICAL NOT
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET
                  ;
                  ;       JSR     DLNOTI
                  ;
                  ;       DTAB(X) = LOGICAL NOT DTAB(X)
                  ;

9D57  205E9D      DLNOTI  JSR     DTXP            ; TRUE OR FALSE?
9D5A  F0EE ^9D4A          BEQ     DTRUE           ; FALSE -> TRUE AND EXIT.
9D5C  D0F0 ^9D4E          BNE     DFALSE          ; TRUE -> FALSE AND EXIT.


9D5E                      PROC
                  ;
                  ; DTXP -- DTAB(X) PREDICATE
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET
                  ;
                  ;       JSR DTXP
                  ;
                  ;       BNE IF DTAB(X) POSITIVE (TRUE)
                  ;       BEQ IF DTAB(X) ZERO OR NEGATIVE (FALSE)
                  ;

9D5E  B581        DTXP    LDA     DTAB+1,X
9D60  3003 ^9D65          BMI     DTX010          ; NEGATIVE.
9D62  1580                ORA     DTAB,X          ; POSITIVE OR ZERO.
9D64  60                  RTS                     ; CC IS SET.

9D65              DTY010
9D65  A900        DTX010  LDA     #0
9D67  60                  RTS


                  ;
                  ; DANDI -- DOUBLE PRECISION AND
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ; X = OFFSET
                  ; Y = OFFSET
                  ;
                  ; JSR DANDI
                  ;
                  ; DTAB(X) = DTAB(X)

9D68  B580        DANDI   LDA     DTAB,X
9D6A  398000              AND     DTAB,Y
9D6D  9580                STA     DTAB,X
9D6F  B581                LDA     DTAB+1,X
9D71  398100              AND     DTAB+1,Y
9D74  9581                STA     DTAB+1,X
9D76  60                  RTS


                  ;
                  ; DORI -- DOUBLE PRECISION OR
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET
                  ;       Y = OFFSET
                  ;
                  ;       JSR     DORI
                  ;
                  ;       DTAB(X) = DTAB(X) OR DTAB(Y)
                  ;
9D77  B580        DORI    LDA     DTAB,X
9D79  198000              ORA     DTAB,Y
9D7C  9580                STA     DTAB,X
9D7E  B581                LDA     DTAB+1,X
9D80  198100              ORA     DTAB+1,Y
9D83  9581                STA     DTAB+1,X
9D85  60                  RTS


                  ;
                  ; DXORI -- DOUBLE PRECISION XOR
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET
                  ;       Y = OFFSET
                  ;
                  ;       JSR     DXORI
                  ;
                  ;       DTAB(X) = DTAB(X) XOR DTAB(Y)
                  ;
9D86  B580        DXORI   LDA     DTAB,X
9D88  598000              EOR     DTAB,Y
9D8B  9580                STA     DTAB,X
9D8D  B581                LDA     DTAB+1,X
9D8F  598100              EOR     DTAB+1,Y
9D92  9581                STA     DTAB+1,X
9D94  60                  RTS


                  ;
                  ; DNOTI -- DOUBLE PRECISION NOT
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET
                  ;
                  ;       JSR     DNOTI
                  ;
                  ;       DTAB(X) = NOT DTAB(X)
                  ;
9D95  B580        DNOTI   LDA     DTAB,X
9D97  49FF                EOR     #$FF
9D99  9580                STA     DTAB,X
9D9B  B581                LDA     DTAB+1,X
9D9D  49FF                EOR     #$FF
9D9F  9581                STA     DTAB+1,X
9DA1  60                  RTS

      = 0000              IF      LOGGRP
   -                      PROC
                  ; DTYP -- DTAB(Y) PREDICATE.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       Y = OFFSET
                  ;
                  ;       JSR     DTYP
                  ;
                  ;       BNE IF DTAB(Y) POSITIVE (TRUE)
                  ;       BEQ IF DTAB(Y) ZERO OR NEGATIVE (FALSE)
                  ;
   -              DTYP    LDA     DTAB+1,Y
   -                      BMI     DTY010          ; NEGATIVE.
   -                      ORA     DTAB,Y          ; POSITIVE OR ZERO.
   -                      RTS                     ; CC IS SET.
                          ENDIF


9DA2                      PROC
                  ;
                  ; ACCUMULATOR FUNCTIONS -- ASSUME THE EXISTENCE OF A DOUBLE PRECISION
                  ; VARIABLE WITHIN 'DTAB' NAMED 'ACC'.
                  ;

                  ;
                  ; DLOADA -- LOAD 'ACC' WITH DATA
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       Y = OFFSET TO SOURCE DATA
                  ;
                  ;       JSR     DLOADA
                  ;
                  ;       X = ACC OFFSET
                  ;       'ACC' = DTAB(Y)
                  ;
9DA2  A262        DLOADA  LDX     #ACC-DTAB
9DA4  4C459A              JMP     DMOVI


9DA7                      PROC
                  ;
                  ; DSTORA -- STORE 'ACC' TO LOCATION
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = OFFSET TO DESTINATION
                  ;
                  ;       JSR     DSTORA
                  ;
                  ;       Y = 'ACC' OFFSET
                  ;       DTAB(X) = 'ACC'
                  ;
9DA7  A062        DSTORA  LDY     #ACC-DTAB
9DA9  4C459A              JMP     DMOVI

9DAC                      PROC
                  ;
                  ; DADDA -- ADD DATA TO 'ACC'
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       Y = OFFSET TO DATA
                  ;
                  ;       JSR     DADDA
                  ;
                  ;       X = 'ACC' OFFSET
                  ;       'ACC' = 'ACC' + DTAB(Y)
                  ;
9DAC  A262        DADDA   LDX     #ACC-DTAB
9DAE  4C329C              JMP     DADDI


9DB1                      PROC
                  ;
                  ; DSUBA -- SUBTRACT DATA PROM 'ACC'
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       Y = OFFSET TO DATA
                  ;
                  ;       JSR     DSUBA
                  ;       BEQ     RESULT = 0
                  ;
                  ;       X = 'ACC' OFFSET
                  ;       'ACC' = 'ACC' - DTAB(Y)
                  ;

                  ;
9DB1  A262        DSUBA   LDX     #ACC-DTAB
9DB3  4C429C              JMP     DSUBI


9DB6                      PROC
                  ;
                  ; DCMPA -- COMPARE 'ACC' WITH DATA (UNSIGNED)
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       Y = DATA OFFSET
                  ;
                  ;       JSR     DCMPA
                  ;
                  ;       CC = 'ACC' : DTAB(Y) (UNSIGNED)
                  ;       X = 'ACC' OFFSET
                  ;
9DB6  A262        DCMPA   LDX     #ACC-DTAB
9DB8  4C159C              JMP     DCMPI

9DBB                      PROC
                  ;
                  ; ASCDEC -- DECIMAL IN ASCII TO BINARY CONVERSION
                  ;
                  ; CALLING SEGUENCE:
                  ;
                  ;       X = DTAB OFFSET TO POINTER VARIABLE
                  ;       Y = OFFSET WITHIN STRING TO START OF NUMBER
                  ;
                  ;       JSR     ASCDEC
                  ;
                  ;       'NUMBER' = RESULT OF CONVERSION (MODULO 2**16)
                  ;       Y = INDEX TO END OF NUMBER DELIMITER
                  ;       USES 'TEMP' THRU 'TEMP'+4
                  ;
9DBB  A900        ASCDEC  LDA     #0              ; INITIALIZE RESULT.
9DBD  85B8                STA     NUMBER
9DBF  85B9                STA     NUMBER+1

9DC1  B580                LDA     DTAB,X          ; MOVE POINTER.
9DC3  85A3                STA     TEMP+2
9DC5  B581                LDA     DTAB+1,X
9DC7  85A4                STA     TEMP+3
9DC9  B583                LDA     DTAB+3,X        ; SAVE END INDEX.
9DCB  85A5                STA     TEMP+4

9DCD  B1A3                LDA     (TEMP+2),Y
9DCF  C92D                CMP     #'-'            ; UNARY MINUS?
9DD1  D009 ^9DDC          BNE     :AC010          ; NO.

9DD3  C8                  INY                     ; YES -- SKIP OVER IT.
9DD4  20DC9D              JSR     :AC010          ; *** RECURSIVE CALL ***.
9DD7  A238                LDX     #NUMBER-DTAB
9DD9  4CF19C              JMP     DNEGI           ; NEGATE RESULT & RETURN.


9DDC  C4A5        :AC010  CPY     TEMP+4          ; END OF STRING?
9DDE  F033 ^9E13          BEQ     :AC090          ; YES.

9DE0  B1A3                LDA     (TEMP+2),Y      ; GET A CHARACTER.
9DE2  20839E              JSR     CNUMBR          ; VALID DECIMAL DIGIT?
9DE5  B02C ^9E13          BCS     :AC090          ; NO -- DONE.

9DE7  C8                  INY
9DE8  48                  PHA                     ; YES -- SAVE IT.
9DE9  06B8                ASL     NUMBER          ; X2.
9DEB  26B9                ROL     NUMBER+1

9DED  A5B9                LDA     NUMBER+1        ; SAVE X2.
9DEF  85A2                STA     TEMP+1
9DF1  A5B8                LDA     NUMBER
9DF3  85A1                STA     TEMP

9DF5  0A                  ASL     A               ; X4.
9DF6  26B9                ROL     NUMBER+1
9DF8  0A                  ASL     A               ; X8.
9DF9  26B9                ROL     NUMBER+1

9DFB  18                  CLC                     ; X10 = X8 + X2.
9DFC  65A1                ADC     TEMP
9DFE  85B8                STA     NUMBER
9E00  9003 ^9E05          BCC     :AC020          ; NO CARRY.

9E02  E6B9                INC     NUMBER+1        ; CARRY -- ADD TO MSB.
9E04  18                  CLC



9E05  68          :AC020  PLA                     ; GET NEW DIGIT.
9E06  65B8                ADC     NUMBER          ; ADD TO PARTIAL RESULT.
9E08  85B8                STA     NUMBER
9E0A  A5B9                LDA     NUMBER+1
9E0C  65A2                ADC     TEMP+1
9E0E  85B9                STA     NUMBER+1
9E10  4CDC9D              JMP     :AC010

9E13  60          :AC090  RTS


9E14                      PROC
                  ;
                  ; DECASC -- BINARY TO DECIMAL IN ASCII CONVERSION
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = DTAB INDEX TO SIGNED VALUE
                  ;
                  ;       JSR     DECASC
                  ;
                  ;       PRINTS RESULT TO 'CHOT' ROUTINE
                  ;       USES 'TEMP'+2 THRU 'TEMP'+5 & 'TEMP2' THRU 'TEMP2'+2
                  ;
9E14  84A6        DECASC  STY     TEMP+5          ; SAVE Y REGISTER.
9E16  B580                LDA     DTAB,X          ; MOVE DATA TO TEMPORARY STORAGE.
9E18  85A7                STA     TEMP2
9E1A  B581                LDA     DTAB+1,X
9E1C  85A8                STA     TEMP2+1
9E1E  100A ^9E2A          BPL     :DC020          ; NUMBER IS POSITIVE.

9E20  A227                LDX     #TEMP2-DTAB     ; NEGATE NUMBEP.
9E22  20F19C              JSR     DNEGI
9E25  A92D                LDA     #'-'             ; PRINT LEADING MINUS SIGN.
9E27  208294              JSR     CHOT            ; PRINT A CHARACTER.

9E2A  A000        :DC020  LDY     #0              ; INITIALIZE CONVERSION INDEX ...
9E2C  84A9                STY     TEMP2+2         ; ... & LEADING ZERO SUPPRESS FLAG.

9E2E  B9799E      :DC030  LDA     PTEN,Y          ; GET POWER OF TEN.
9E31  85A3                STA     TEMP+2
9E33  B97A9E              LDA     PTEN+1,Y
9E36  85A4                STA     TEMP+3
9E38  84A5                STY     TEMP+4          ; SAVE INDEX TO TABLE.

9E3A  A930                LDA     #'0'             ; INITIALIZE DIGIT.
9E3C  8D1105              STA     DIGIT
9E3F  A227                LDX     #TEMP2-DTAB     ; PREPARE FOR SUCCESSIVE SUBTRACTION.
9E41  A023                LDY     #TEMP+2-DTAB

9E43  20429C      :DC040  JSR     DSUBI
9E46  A5A8                LDA     TEMP2+1         ; SEE IF RESULT IS NEGATIVE.
9E48  3005 ^9E4F          BMI     :DC045          ; YES -- ENOUGH ALREADY.

9E4A  EE1105              INC     DIGIT           ; NO -- KEEP SUBTRACTING.
9E4D  D0F4 ^9E43          BNE     :DC040          ; (BRA).

9E4F  20329C      :DC045  JSR     DADDI           ; NOW CORRECT FROM ONE TOO MANY SUBTRACTS.

9E52  A5A9                LDA     TEMP2+2         ; SEE IF NON-ZERO DIGIT HAS BEEN PRINTED YET.
9E54  D009 ^9E5F          BNE     :DC050          ; YES -- PRINT ALL SUBSEQUENT DIGITS.

9E56  AD1105              LDA     DIGIT           ; NO -- SEE IF THIS DIGIT IS ANOTHER ZERO.
9E59  C930                CMP     #'0'
9E5B  F008 ^9E65          BEQ     :DC060          ; YES IT IS -- SUPPRESS IT.

9E5D  85A9                STA     TEMP2+2         ; NO -- SET FLAG AND PRINT DIGIT.

9E5F  AD1105      :DC050  LDA     DIGIT           ; PRINT DIGIT.
9E62  208294              JSR     CHOT

9E65  A4A5        :DC060  LDY     TEMP+4          ; RESTORE TABLE INDEX.
9E67  C8                  INY
9E68  C8                  INY
9E69  C00A                CPY     #PTENL          ; DONE?
9E6B  D0C1 ^9E2E          BNE     :DC030          ; NO.

9E6D  A5A9                LDA     TEMP2+2         ; WAS THE NUMBER = 0?
9E6F  D005 ^9E76          BNE     :DC070          ; NO.

9E71  A930                LDA     #'0'             ; YES -- PRINT SINGLE ZERO DIGIT.
9E73  208294              JSR     CHOT

9E76  A4A6        :DC070  LDY     TEMP+5          ; YES -- RESTORE Y REGISTER ...
9E78  60                  RTS                     ; ... & RETURN.

9E79  1027E80364  PTEN    DW   10000,1000,100,10,1     ; DECREASING POWERS OF TEN.
      = 000A      PTENL = *-PTEN                            ; TABLE LENGTH IN WORDS.

9E83                      PROC
                  ;
                  ; CNUMBR -- CHECK ASCII CHARACTER FUR VALID NUMBER ('0 - '9)
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       A = ASCII CHAPACTER
                  ;
                  ;       JSR     CNUMBR
                  ;       BCS     NOT DECIMAL DIGIT
                  ;
                  ;       A = BINARY DIGIT
                  ;
9E83  C930        CNUMBR  CMP     #'0'             ; < '0?
9E85  9004 ^9E8B          BCC     :CN010          ; YES -- INVALID.

9E87  C93A                CMP     #'9'+1           ; > '9?
9E89  9002 ^9E8D          BCC     :CN020          ; NO -- VALID DECIMAL DIGIT.
9E8B  38          :CN010  SEC                     ; SET CARRY FOR EXIT.
9E8C  60                  RTS
9E8D  E92F        :CN020  SBC     #'0'-1          ; (ADJUST FOR CARRY CLEAR).
9E8F  18                  CLC                     ; SET CC FOR EXIT.
9E90  60                  RTS


9E91                      PROC
                  ;
                  ; CLETTR -- CHECK ASCII CHARACTER FOR ALPHA LETTER ('A - 'Z)
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       A = ASCII CHARACTER
                  ;
                  ;       JSR     CLETTR
                  ;       BCS     NOT ALPHA LETTER
                  ;
                  ;       A = ASCII CHARACTER
                  ;
9E91  48          CLETTR  PHA                     ; SAVE CHARACTER.
9E92  29DF                AND     #UC             ; FORCE UPPER CASE.
9E94  C941                CMP     #'A'            ; < 'A?
9E96  9004 ^9E9C          BCC     :CL010          ; YES -- NOT ALPHA.
9E98  C95B                CMP     #'Z'+1           ; > 'Z?
9E9A  9001 ^9E9D          BCC     :CL020          ; NO -- VALID LETTFR
9E9C  38          :CL010  SEC                     ; SET CARRY FOR EXIT
9E9D  68          :CL020  PLA                     ; RESTORE CHARACTER.
9E9E  60                  RTS


9E9F                      PROC
                  ;
                  ; STMLST -- SETUP LIST POINTER TO STATEMENT LIST
                  ;
9E9F              STMLST
9E9F  A5AE                LDA     S1L             ; 'LP' = 'S1L'.
9EA1  85BA                STA     LP
9EA3  A5AF                LDA     S1L+1
9EA5  85BB                STA     LP+1
9EA7  A900                LDA     #ATRLIN         ; 'LIN' FOR LINE
9EA9  8D6605              STA     ATRTYP
9EAC  60                  RTS


9EAD                      PROC
                  ;
                  ; SETSVL -- SETUP LIST POINTER TO NAMED STRING LIST
                  ;
9EAD  A5B2        SETSVL  LDA     S2L             ; 'LP' = 'S2L'.
9EAF  85BA                STA     LP
9EB1  A5B3                LDA     S2L+1
9EB3  85BB                STA     LP+1
9EB5  60                  RTS


9EB6                      PROC
                  ;
                  ; CKEOA -- CHECK FOR END OF ATOM (NON- ALPHANUMERIC CHARACTER)
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       A = ASCII CHARACTER
                  ;
                  ;       JSR     CKEOA
                  ;       BEQ     END OF ATOM (NOT AN ALPHANUMERIC CHARACTER)
                  ;
9EB6  20919E      CKEOA   JSR     CLETTR          ; ALPHA LETTER
9EB9  900C ^9EC7          BCC     :CK090          ; YES.

9EBB  48                  PHA
9EBC  20839E              JSR     CNUMBR          ; NO -- NUMERIC CHARACTER?
9EBF  68                  PLA
9EC0  9005 ^9EC7          BCC     :CK090          ; YES.
9EC2  85A1                STA     TEMP            ; NEITHER -- SET CC FOR EXIT.
9EC4  C5A1                CMP     TEMP
9EC6  60                  RTS
9EC7  C9FF        :CK090  CMP     #$FF            ; SET CC FOR E
9EC9  60                  RTS

                  ;
                  ; SCEOA -- SCAN TO END OF ATOM
                  ;
9ECA  C8                  INY

9ECB  B180        SCEOA   LDA     (INLN),Y
9ECD  20B69E              JSR     CKEOA           ; END OF ATOM?
9ED0  D0F8 ^9ECA          BNE     SCEOA-1         ; NO.

9ED2  60                  RTS                     ; YES -- RETURN WITH CC SET.


9ED3                      PROC
                  ;
                  ; SCNLBL -- IDENTIFY (& SCAN TO END OF) LABEL
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       Y = INDEX TO INPUT LINE.
                  ;
                  ;       JSR     SCNLBL
                  ;       BNE     NO LABEL PRESENT (A = CODE)
                  ;
                  ;       Y = INDEX TO END OF LABEL + 1
                  ;  INDENT = INDEX TO FIRST NON-SEPARATOR.
                  ;
                  ; NOTE: JUMPS TO 'PSTOP' IF INVALID LABEL NAME FOUND.
                  ;
9ED3  20079F      SCNLBL  JSR     SKPSEP          ; SKIP LEADING BLANKS AND/OR COMMAS.
9ED6  8CCA05              STY     INDENT          ; UPDATE # AUTO INDENT
9ED9  C92A                CMP     #'*'            ; LABEL PREFIX DELIMITER?
9EDB  F003 ^9EE0          BEQ     :SL005          ; YES.

9EDD  A902                LDA     #IMPERR         ; NO LABEL.
9EDF  60                  RTS

9EE0  C8          :SL005  INY
9EE1  B180                LDA     (INLN),Y
9EE3  20B69E              JSR     CKEOA           ; SEE IF AT LEAST ONE ALPHANUMERIC.
9EE6  D0E3 ^9ECB          BNE     SCEOA           ; YES -- SCAN TO END OF ATOM & RETURN.

9EE8  A902                LDA     #ATMERR         ; NO -- INVALID LABEL NAME.
9EEA  4C3A7A              JMP     PSTOP


9EED                      PROC
                  ;
                  ; CHKSEP -- CHECK FOR OPERAND SEPARATOR CHARACTER
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       A = CHARACTER.
                  ;
                  ;       JSR     CHKSEP
                  ;       BNE     NOT A SEPARATOR
                  ;
9EED  C920        CHKSEP  CMP     #' '            ; BLANK?
9EEF  F007 ^9EF8          BEQ     :CS090          ; YES.

9EF1  C92C                CMP     #','            ; COMMA?
9EF3  F003 ^9EF8          BEQ     :CS090          ; YES.

9EF5  4CF99E              JMP     CHKTRM          ; END OF STATEMENT CHECK & RETURN.

9EF8  60          :CS090  RTS


9EF9                      PROC
                  ;
                  ; CHKTRM -- CHECK FOR STATEMENT TERMINATOR (EOL OR '[').
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       A = CHARACTER.
                  ;
                  ;       JSR CHKTRM
                  ;       BNE NOT STATEMENT TERMINATOR.
                  ;

9EF9  C99B        CHKTRM  CMP     #EOL
9EFB  F002 ^9EFF          BEQ     :CK090

9EFD  C95B                CMP     #SBRACK

9EFF  60          :CK090  RTS


9F00                      PROC
                  ;
                  ; CHKEQS -- CHECK FOR EQUAL SIGN
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       Y = 'INLN' INDEX.
                  ;
                  ;       JSR     CHKEQS
                  ;       BEQ     1ST NON-BLANK CHARACTER WAS '='.
                  ;
                  ;       Y = 'INLN' INDEX TO 1ST NON-BLANK CHAR.
                  ;
9F00  20139F      CHKEQS  JSR     SLB             ; SKIP LEADING BLANKS.
9F03  C93D                CMP     #'='
9F05  60                  RTS                     ; RETURN WITH CC SET.


9F06                      PROC
                  ;
                  ; SKPSEP -- SKIP OPERAND SEPARATOR(S)
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ; Y = INDEX TO INPUT LINE
                  ;
                  ; JSR SKPSEP
                  ;
                  ; Y = INDEX TO FIRST NON-SEPARATOR FOUND
                  ;
                  ; NOTE: ANY STRING OF CONSECUTIVE BLANKS AND/OR COMMAS IS TREATED AS A SINGLE
                  ;       SEPARATOR.
                  ;
9F06  C8                  INY

9F07  B180        SKPSEP  LDA     (INLN),Y
9F09  C920                CMP     #' '             ; BLANK?
9F0B  F0F9 ^9F06          BEQ     SKPSEP-1        ; YES.

9F0D  C92C                CMP     #','             ; COMMA?
9F0F  F0F5 ^9F06          BEQ     SKPSEP-1        ; YES.

9F11  60                  RTS


9F12                      PROC
                  ;
                  ; SLB -- SKIP LEADING BLANKS
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       JSR     SLB
                  ;
                  ;       A = FIRST NON-BLANK CHARACTER FOUND.
                  ;
9F12  C8                  INY

9F13  B180        SLB     LDA     (INLN),Y
9F15  C920                CMP     #' '             ; BLANK?
9F17  F0F9 ^9F12          BEQ     SLB-1           ; YES -- KEEP SCANNING.

9F19  60                  RTS


9F1A                      PROC
                  ;
                  ; SCNEOL -- SCAN TO END OF LINE
                  ;
9F1A  C8                  INY

9F1B  B180        SCNEOL  LDA     (INLN),Y
9F1D  C99B                CMP     #EOL
9F1F  D0F9 ^9F1A          BNE     SCNEOL-1

9F21  60                  RTS                     ; RETURN WITH CC SET.


9F22                      PROC
                  ;
                  ; PSF -- PRINT A STORAGE FORMAT LINE
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       Y = INDEX TO LINE POINTER.
                  ;
                  ;       JSR     PSF
                  ;
9F22  A236        PSF     LDX     #POINT-DTAB     ; MOVE POINTER TO 'POINT'.
9F24  20459A              JSR     DMOVI
9F27  208C9F              JSR     GTLNNO          ; GET LINE A TO 'LINENO'.

9F2A  A6DD                LDX     LINENO+1        ; LEADING SPACES TO RIGHT-JUSTIFY LINE A.
9F2C  E003                CPX     # HIGH 1000     ; >= 1000?
9F2E  9008 ^9F38          BCC     :PS002          ; NO.
9F30  D01C ^9F4E          BNE     :PS003          ; YES.
9F32  A5DC                LDA     LINENO
9F34  C9E8                CMP     # LOW 1000
9F36  B016 ^9F4E          BCS     :PS003          ; YES.
9F38  20A29F      :PS002  JSR     SPACE

9F3B  8A                  TXA                     ; >= 100?
9F3C  D010 ^9F4E          BNE     :PS003          ; YES.
9F3E  A6DC                LDX     LINENO
9F40  E064                CPX     # 100           ; >= 100?
9F42  B00A ^9F4E          BCS     :PS003          ; YES.
9F44  20A29F              JSR     SPACE

9F47  E00A                CPX     # 10            ; >= 10?
9F49  B003 ^9F4E          BCS     :PS003          ; YES.
9F4B  20A29F              JSR     SPACE

9F4E  A25C        :PS003  LDX     #LINENO-DTAB
9F50  20149E              JSR     DECASC          ; PRINT BINARY LINE #.

9F53  C8                  INY                     ; LOOK AHEAD TO 1ST CHAR OF STATEMENT.
9F54  C8                  INY
9F55  A920                LDA     #' '            ; IS IT A SPACE?
9F57  D1B6                CMP     (POINT),Y
9F59  F003 ^9F5E          BEQ     :PS005          ; YES.

9F5B  20A29F              JSR     SPACE           ; NO -- PUT SPACE BETWEEN LINE A AND STATEMENT.

9F5E  88          :PS005  DEY                     ; GET STATEMENT LENGTH.
9F5F  B1B6                LDA     (POINT),Y
9F61  AA                  TAX

9F62  CEFE02              DEC     DSPFLG          ; DISPLAY CONTROL CHARACTERS.

9F65  C8          :PS010  INY                     ; PRINT STATEMENT BODY.
9F66  B1B6                LDA     (POINT),Y
9F68  208294              JSR     CHOT
9F6B  CA                  DEX
9F6C  D0F7 ^9F65          BNE     :PS010

9F6E  EEFE02              INC     DSPFLG          ; BACK TO ZERO.

9F71  60                  RTS

9F72                      PROC
                  ;
                  ; NULACC -- SET THE ACCEPT BUFFER TO NULL (SINGLE SPACE)
                  ;
9F72  A000        NULACC  LDY     #0
9F74  A920                LDA     #' '             ; SINGLE SPACE.
9F76  9188                STA     (ACLN),Y
9F78  848A                STY     ACLN+2          ; START INDEX.
9F7A  C8                  INY
9F7B  848B                STY     ACLN+3          ; END INDEX.
9F7D  60                  RTS


9F7E                      PROC
                  ;
                  ; ABRTCK -- BREAK KEY ABORT CHECK
                  ;
9F7E  48          ABRTCK  PHA                     ; (SEE 'XSYNC').
9F7F  A511                LDA     BREAK           ; OPERATOR ABORT?
9F81  D007 ^9F8A          BNE     :AC090          ; NO.

9F83  C611                DEC     BREAK           ; YES -- RESET FLAG.

9F85  A987        :AC005  LDA     #ABTERR         ; STOP WITH STATUS CODE.
9F87  4C3A7A              JMP     PSTOP
      = 0000              IF      FALSE
   -              :AC010  LDA     CONKEY          ; ALTERNATE ABORT?
   -                      AND     #STRTKY         ; START KEY?
   -                      BEQ     :AC090          ; NO.

   -                      LDA     CONKEY          ; YES -- RESET STATUS.
   -                      AND     #$FF-STRTKY
   -                      STA     CONKEY
   -                      JMP     :AC005
                          ENDIF

9F8A  68          :AC090  PLA
9F8B  60                  RTS

9F8C                      PROC
                  ;
                  ; GTLNNO -- GET LINE # FROM STORAGE LINE
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'POINT' POINTS TO STORAGE LINE
                  ;
                  ;       JSR     GTLNNO
                  ;
                  ;       'LINENO' = BINARY LINE #
                  ;       Y = 4
                  ;
9F8C  A003        GTLNNO  LDY     #3
9F8E  B1B6                LDA     (POINT),Y
9F90  85DD                STA     LINENO+1        ; RE-INVERT ORDER.
9F92  C8                  INY
9F93  B1B6                LDA     (POINT),Y
9F95  85DC                STA     LINENO
9F97  60                  RTS


9F98                      PROC
                  ; NEWLIN -- ISSUE NEW LINE SEQUENCE TO 'CHOT'

9F98  A99B        NEWLIN  LDA     #EOL
9F9A  4C8294              JMP     CHOT            ; NEWLINE & RETURN.


9F9D                      PROC
                  ; SPACE(S) -- ISSUE SPACE(S) TO 'CHOT'

9F9D  A920        SPACES  LDA     #' '            ; TWO SPACES.
9F9F  208294              JSR     CHOT

9FA2  A920        SPACE   LDA     #' '            ; ONE SPACE.
9FA4  4C8294              JMP     CHOT            ; & RETURN.


9FA7                      PROC
                  ;
                  ; CRSNOP -- COMPLICATED NOP TO UPDATE CURSOR INHIBIT/ENABLE STATE
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       A = 0 TO ENABLE CURSOR, ELSE DISABLE CURSOR.
                  ;
9FA7  8DF002      CRSNOP  STA     CRSINH          ; SET CURSOR INHIBIT FLAG.
9FAA  A91C                LDA     #CUP            ; CURSOR UP ...
9FAC  208294              JSR     CHOT
9FAF  A91D                LDA     #CDOWN          ; ... THEN DOWN ...
9FB1  4C8294              JMP     CHOT            ; ... & RETURN.


9FB4                      PROC
                  ;
                  ; AUDCLR -- CLEAR AUDIO REGISTERS AND SELECTS
                  ;

9FB4  A903        AUDCLR  LDA     #$03            ; MAGIC CONSTANT FROM D. CRANE, 27-AUG-79.
9FB6  8D3202              STA     SSKCTL
9FB9  8D0FD2              STA     SKCTL

9FBC  A900                LDA     #0
9FBE  8D08D2              STA     AUDCTL          ; SET AUDIO TO 4 INDEPENDENT REGISTERS.

9FC1  A208                LDX     #AUREGS*2

9FC3  9DFED1      :AC010  STA     AUDF1-2,X       ; CLEAR ALL ACTIVE TONES.
9FC6  9DFFD1              STA     AUDC1-2,X
9FC9  9D1305              STA     AUDIOR-2,X      ; CLEAR 'SO' SELECTS.
9FCC  9D1405              STA     AUDIOR-1,X
9FCF  CA                  DEX
9FD0  CA                  DEX
9FD1  D0F0 ^9FC3          BNE     :AC010

9FD3  60                  RTS

9FD4                      PROC
                  ;
                  ; EXP -- ARITHMETIC EXPRESSION EVALUATOR
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'INLN' POINTS TO LINE TO BE EVALUATED
                  ;       Y = INDEX TO START OF EXPRESSION
                  ;
                  ;       JSR     EXP
                  ;
                  ;       Y = INDEX TO END OF EXPRESSION + 1
                  ;       'EXPSTK'+0 & +1 = RESULT OF EVALUATION.
                  ;
9FD4  A900        EXP     LDA     #0              ; INITIALIZE CPITICAL VARIABLES.
9FD6  8D4E05              STA     ESTKP

                  ; *** EXTERNAL ENTRY POINT ***

9FD9  2014A0      EXPRC   JSR     EXPVAL          ; CHECK FOR OPERAND & GET VALUE TO STACK.

9FDC  20139F      :EX030  JSR     SLB             ; SKIP LEADING BLANKS.
9FDF  84A7                STY     TEMP2           ; SAVE INDEX.

9FE1  206E81              JSR     ATOM            ; CHECK FOR OPERATOR.
9FE4  D021 ^A007          BNE     :EX080          ; INVALID ATOM.

9FE6  C940                CMP     #OPR
9FE8  D01D ^A007          BNE     :EX080          ; NOT AN OPERATOR.

9FEA  AE4E05              LDX     ESTKP           ; PUSH OPERATOR ROUTINE ADDR TO EXP STACK.
9FED  E00E                CPX     #ESTKSZ
9FEF  F019 ^A00A          BEQ     EXP192          ; STACK FULL.

9FF1  A5B6                LDA     POINT
9FF3  9593                STA     EXPSTK,X
9FF5  A5B7                LDA     POINT+1
9FF7  9594                STA     EXPSTK+1,X
9FF9  E8                  INX
9FFA  E8                  INX
9FFB  8E4E05              STX     ESTKP

9FFE  2014A0              JSR     EXPVAL          ; CHECK FOR OPERAND & GET VALUE TO STACK.

A001  207CA0              JSR     SOP             ; OPERATE ON STACK DATA.
A004  4CDC9F              JMP     :EX030

A007  A4A7        :EX080  LDY     TEMP2
A009  60                  RTS

A00A  A902        EXP192  LDA     #EXPERR
A00C  4C3A7A      EXP194  JMP     PSTOP


A00F                      PROC
                  ;
                  ; EXPVAL -- VALIDATE OPERAND & PUSH VALUE TO STACK
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       Y = INDEX TO 'INLN'
                  ;
                  ;       JSR     EXPVAL
                  ;
A00F  A900        EXPP    LDA     #0              ; EVALUATE EXPR IN PARENS.
A011  8D4E05              STA     ESTKP

A014  20139F      EXPVAL  JSR     SLB
A017  A202                LDX     #UNTABX         ; UNARY OPERATOR?
A019  20AB7C              JSR     SBCMAT
A01C  D01D ^A03B          BNE     :EX010          ; NO.

A01E  8A                  TXA                     ; YES.
A01F  48                  PHA                     ; SAVE OFFSET IN 'SBDTAB'.
A020  2014A0              JSR     EXPVAL          ; *** RECURSIVE CALL ***

A023  68                  PLA                     ; RESTORE OFFSET IN 'SBDTAB'.
A024  AA                  TAX
A025  BDAA80              LDA     SBDTAB,X        ; GET OPERATOR ROUTINE ADDRESS.
A028  8D0E05              STA     SJUMP+1
A02B  BDAB80              LDA     SBDTAB+1,X
A02E  8D0F05              STA     SJUMP+2

A031  AD4E05              LDA     ESTKP           ; GET OFFSET TO RESULT.
A034  18                  CLC
A035  6911                ADC     #EXPSTK-DTAB-2
A037  AA                  TAX
A038  4C0D05              JMP     SJUMP           ; UNARY ROUTINE & RETURN.

A03B  B180        :EX010  LDA     (INLN),Y        ; RESTORE CHAR.
A03D  C928                CMP     #'('            ; LEFT PAREN?
A03F  D00C ^A04D          BNE     :EX020 ; NO.

A041  C8                  INY
A042  20D99F              JSR     EXPRC           ; YES -- EVALUATE SUB-EXPRESSION.
A045  B180                LDA     (INLN),Y
A047  C929                CMP     #')'            ; MATCHING RIGHT RAREN?
A049  D0BF ^A00A          BNE     EXP192          ; NO -- ERROR.

A04B  C8                  INY                     ; YES -- SKIP OVER IT.
A04C  60                  RTS

A04D  C93F        :EX020  CMP     #'?'            ; RANDOM NUMBER?
A04F  D00D ^A05E          BNE     :EX030          ; NO.

A051  AD0AD2              LDA     PKYRND          ; YES -- GET RANDOM # FROM POKEY.
A054  85B8                STA     NUMBER
A056  AD0AD2              LDA     PKYRND
A059  85B9                STA     NUMBER+1
A05B  C8                  INY                     ; SKIP OVER '?'.
A05C  D009 ^A067          BNE     :EX040          ; (BRA).


A05E  206E81      :EX030  JSR     ATOM
A061  D0A9 ^A00C          BNE     EXP194          ; ERROR.
A063  2986                AND     #NUM+NVAR+BPTR  ; NUMERIC VARIABLE, POINTER OR CONSTANT?
A065  F0A3 ^A00A          BEQ     EXP192          ; NO -- ERROR.
A067  AE4E05      :EX040  LDX     ESTKP           ; RESULT TO STACK.
A06A  E00E                CPX     #ESTKSZ
A06C  F09C ^A00A          BEQ     EXP192          ; STACK OVERFLOW.
A06E  A5B8                LDA     NUMBER
A070  9593                STA     EXPSTK,X
A072  A5B9                LDA     NUMBER+1
A074  9594                STA     EXPSTK+1,X
A076  E8                  INX
A077  E8                  INX
A078  8E4E05              STX     ESTKP
A07B  60                  RTS


A07C                      PROC
                  ;
                  ; SOP -- STACK OPERATE
                  ;
                  ; CALLING SEQUENCE:
                  ;
A07C  A592        SOP     LDA     EXEC            ; EXECUTE?
A07E  F01D ^A09D          BEQ     :SO050          ; NO -- JUST REJUSTIFY THE STACK.
A080  84A7                STY     TEMP2
A082  AD4E05              LDA     ESTKP           ; GET EXP STACK INDEX.
      = 0000              IF      DEBUG
   -                      CMP     #6              ; SEE IF STACK HAS AT LEAST 3 ENTRIES.
   -                      BCC     :SO090          ; NO -- PROBLEM!
                          ENDIF
A085  18                  CLC                     ; YES -- CONVERT STACK INDEX TO 'DTAB'
A086  6911                ADC     #EXPSTK-DTAB-2
A088  A8                  TAY
A089  AA                  TAX
A08A  CA                  DEX                     ; INDEX TO OPERATOR PROCESSOR ADDRESS.
A08B  CA                  DEX
A08C  B580                LDA     DTAB,X          ; GET OPERATE ROUTINE ADDRESS.
A08E  8D0E05              STA     SJUMP+1
A091  B581                LDA     DTAB+1,X
A093  8D0F05              STA     SJUMP+2
A096  CA                  DEX                     ; INDEX TO TARGET ENTRY.
A097  CA                  DEX
A098  200D05              JSR     SJUMP           ; OPERATE ON DATA.
A09B  A4A7                LDY     TEMP2
A09D  38          :SO050  SEC                     ; (CLEAR BORROW).
A09E  AD4E05              LDA     ESTKP           ; ADJUST STACK INDEX
A0A1  E904                SBC     #4
A0A3  8D4E05              STA     ESTKP
A0A6  60                  RTS
      = 0000              IF      DEBUG
   -              :SO090  LDA     #INTERR         ; INTERNAL BUG
   -                      JMP     PSTOP
                          ENDIF

A0A7                      PROC
                  ;
                  ; TEXP -- EVALUATE TEXT EXPRESSION
                  ;
                  ;       Y = POINTER TO START OF TEXT EXPR IN 'INLN'.
                  ;
                  ;       JSR     TEXP
                  ;       BNE     EXECUTE MODE
                  ;
                  ;       TEXP+2 = 0
                  ;       TEXP+3 = END OF TEXT EXPRESSION.
                  ;
                  ;       THE EOL IS NOT PART OF THE RESULTANT TEXT.
                  ;

A0A7  A592        TEXP    LDA     EXEC            ; EXECUTE MODE?
A0A9  D003 ^A0AE          BNE     :TE005          ; YES.

A0AB  4C1B9F              JMP     SCNEOL          ; NO -- SCAN TO EOL & RETURN.

A0AE  A900        :TE005  LDA     #0              ; INIT RESULT LENGTH COUNT ...
A0B0  858F                STA     TELN+3
A0B2  858E                STA     TELN+2          ; ... & STARTING INDEX.

A0B4  AD3005              LDA     CDEST           ; SAVE 'CHOT' DESTINATION.
A0B7  8D3105              STA     CDEST+1
A0BA  A9FF                LDA     #$FF            ; YES -- RE-ROUTE 'CHOT' OUTPUT
A0BC  8D3005              STA     CDEST

A0BF  B180        :TE010  LDA     (INLN),Y        ; GET A CHARACTER.
A0C1  20F99E              JSR     CHKTRM          ; STATEMENT TERMINATOR?
A0C4  F05C ^A122          BEQ     :TE400          ; YES.

A0C6  C925                CMP     #'%'            ; SPECIAL NUMBER?
A0C8  F013 ^A0DD          BEQ     :TE100          ; YES.

A0CA  C940                CMP     #'@'            ; POINTER?
A0CC  F00F ^A0DD          BEQ     :TE100          ; YES.

A0CE  C923                CMP     #'#'            ; NUMERIC VARIABLE DELIMITER?
A0D0  F00B ^A0DD          BEQ     :TE100          ; YES.

A0D2  C924                CMP     #'$'            ; STRING VARIABLE DELIMITER?
A0D4  F007 ^A0DD          BEQ     :TE100          ; YES.

A0D6  C8          :TE020  INY
A0D7  208294              JSR     CHOT            ; YES -- PRINT TEXT LITERAL.
A0DA  4CBFA0              JMP     :TE010

A0DD  48          :TE100  PHA                     ; SAVE THE TEXT CHARACTER.
A0DE  98                  TYA                     ; SAVE THE Y REG.
A0DF  48                  PHA

A0E0  206E81              JSR     ATOM            ; GET VALUE.
A0E3  F021 ^A106          BEQ     :TE220          ; O.K.

A0E5  68          :TE210  PLA                     ; NOT ATOM -- RESTORE Y REG ...
A0E6  A8                  TAY

A0E7  C8                  INY                     ; LOOK AHEAD.
A0E8  B180                LDA     (INLN),Y        ; IS NEXT CHAR = DOUBLE QUOTE?
A0EA  C922                CMP     #'"'
A0EC  D014 ^A102          BNE     :TE216          ; NO.

A0EE  68                  PLA                     ; YES -- FLUSH THE '%'
A0EF  C8                  INY                     ; GET NEXT CHARACTER IN LITERAL

A0F0  B180        :TE212  LDA     (INLN),Y
A0F2  20F99E              JSR     CHKTRM          ; STATEMENT TERMINATOR?
A0F5  F02B ^A122          BEQ     :TE400          ; YES.

A0F7  C8                  INY
A0F8  C922                CMP     #'"'            ; LITERAL TERMINATOR?
A0FA  F0C3 ^A0BF          BEQ     :TE010          ; YES -- BACK TO NORMAL SCAN

A0FC  208294              JSR     CHOT            ; NOT PRINT LITERAL CHAR.
A0FF  4CF0A0              JMP     :TE212

A102  88          :TE216  DEY                     ; SET INDEX BACK.
A103  68                  PLA                     ; ... & CHARACTER.
A104  D0D0 ^A0D6          BNE     :TE020          ; (BRA).

A106  C910        :TE220  CMP     #USVAR          ; UNDEFINED STRING?
A108  F0DB ^A0E5          BEQ     :TE210          ; YES -- PRINT LITERALLY.

A10A  C908                CMP     #SVAR           ; DEFINED STRING?
A10C  F00A ^A118          BEQ     :TE300          ; YES -- PRINT VALUE.

                  ; NUMERIC DATA

A10E  68                  PLA                     ; NO -- MUST BE NUMERIC VALUE.
A10F  68                  PLA                     ; CLEAR STACK.

A110  A238                LDX     #NUMBER-DTAB    ; VALUE OF NUMBER.
A112  20149E              JSR     DECASC          ; CONVERT TO ASCII & OUTPUT.
A115  4CBFA0              JMP     :TE010          ; CONTINUE.

                  ; STRING VARIABLE

A118  68          :TE300  PLA                     ; CLEAR THE STACK.
A119  68                  PLA

A11A  A242                LDX     #DP-DTAB        ; INDEX TO STRING VALUE.
A11C  209797              JSR     PRTSTG
A11F  4CBFA0              JMP     :TE010

A122  AD3105      :TE400  LDA     CDEST+1         ; RESTORE 'CHOT' DESTINATION.
A125  8D3005              STA     CDEST

                  ; EXTERNAL ENTRY POINT FROM 'XACCPT' ***

A128  A68F        TRAILB  LDX     TELN+3          ; EXAMINE LAST CHAR OF TEXP.
A12A  E48E                CPX     TELN+2
A12C  F00C ^A13A          BEQ     :TE480          ; NULL RESULT.

A12E  BDFFBB              LDA     TEXBUF-1,X      ; GET LAST CHAR IN BUFFER.
A131  C95F                CMP     #'_'            ; UNDERSCORE?
A133  D005 ^A13A          BNE     :TE480          ; NO.

A135  A920                LDA     #' '            ; YES -- REPLACE WITH BLANK.
A137  9DFFBB              STA     TEXBUF-1,X
A13A  A592        :TE480  LDA     EXEC            ; THE CC IS BEING SET TO REFLECT THE STATE
                                                  ; OF THE 'EXEC' FLAG BECAUSE EVERY SINGLE
                                                  ; JSR TO 'STEP' USED TO BE FOLLOWED BY A
                                                  ; 'LDA EXEC ' INSTRUCTION. THESE HAVE ALL BEEN
                                                  ;"COMMENTED" OUT; WHEN WILL THIS ALL END?
A13C  60                  RTS


                  ;
                  ; HEREIN RESIDE THE LOWER LEVEL GRAPHICS ROUTINES FOR PILOT GRAPHICS.
                  ;
                  ;
A13D                      PROC
                  ;
                  ; GMODE -- GRAPHICS 'MODE' SUBCOMMAND.
                  ;

A13D  20D49F      GMODE   JSR     EXP             ; GET MODE #.

A140  A592                LDA     EXEC            ; EXECUTE MODE.
A142  F026 ^A16A          BEQ     :GM090          ; NO.

A144  84AB                STY     XTEMP
A146  A000                LDY     #0              ; SEE IF MODE IS 0-15.
A148  A910                LDA     #16
A14A  A213                LDX     #EXPSTK-DTAB
A14C  200F9C              JSR     DCWCI
A14F  B01A ^A16B          BCS     :GM092          ; NO -- MODE >=16.

A151  A693                LDX     EXPSTK          ; SEE IF ALLOWED AS GRAPHICS MODE.
A153  BDE6B7              LDA     GCHAR,X         ; WILL BE ZERO IF NOT ALLOWED.
A156  F013 ^A16B          BEQ     :GM092          ; NOT AN ALLOWFD MODE.

A158  AD5205              LDA     SPLTSC          ; SEE IF SPLIT DESIRED.
A15B  F005 ^A162          BEQ     :GM020          ; NO.

A15D  3DE6B7              AND     GCHAR,X         ; YES -- IS SPLIT ALLOWED?
A160  F010 ^A172          BEQ     :GM094          ; NO -- ERROR.

A162  8E3705      :GM020  STX     GSMODE          ; YES -- SAVE MODE.
A165  201095              JSR     GSOPEN          ; RE-OPEN GRAPHICS SCREEN.

A168  A4AB                LDY     XTEMP

A16A  60          :GM090  RTS

A16B  A922        :GM092  LDA     #MODERR         ; ILLEGAL GRAPHICS MODE.
A16D  A4AB                LDY     XTEMP
A16F  4C3A7A              JMP     PSTOP

A172              GSP094
A172  A921        :GM094  LDA     #SPTERR         ; SPLIT SCREEN NOT ALLOWED.
A174  A4AB                LDY     XTEMP
A176  4C3A7A              JMP     PSTOP

A179                      PROC
                  ;
                  ; GFULL -- GRAPHICS 'FULL' SUBCOMMAND.
                  ;
A179  A592        GFULL   LDA     EXEC            ; EXECUTE MODE?
A17B  F015 ^A192          BEQ     :GF090          ; NO.

A17D  A5FF                LDA     RUN             ; RUN MODE?
A17F  F012 ^A193          BEQ     :GF092          ; NO -- ERROR.

A181  AD4505              LDA     SGLSTP          ; SINGLE STOP?
A184  D00D ^A193          BNE     :GF092          ; YES -- ERROR.

A186  A900                LDA     #0              ; FULL SCREEN
A188  8D5205              STA     SPLTSC

A18B  84AB                STY     XTEMP
A18D  201095              JSR     GSOPEN          ; OPEN SCREEN.
A190  A4AB                LDY     XTEMP

A192  60          :GF090  RTS

A193  A983        :GF092  LDA     #NRCERR
A195  4C3A7A              JMP     PSTOP

A198                      PROC
                  ;
                  ; GSPLIT -- GRAPHICS 'SPLIT' SUBCOMMAND.
                  ;

A198  A592        GSPLIT  LDA     EXEC            ; EXECUTE MODE?
A19A  F014 ^A1B0          BEQ     :GS090          ; NO.

A19C  A910                LDA     #SPLIT          ; SPLIT SCPEEN.
A19E  8D5205              STA     SPLTSC

A1A1  AE3705              LDX     GSMODE          ; SEE IF SPLIT ALLOWED.
A1A4  3DE6B7              AND     GCHAR,X
A1A7  F0C9 ^A172          BEQ     GSP094          ; NO -- ERROR.

A1A9  84AB                STY     XTEMP
A1AB  201095              JSR     GSOPEN          ; YES -- OPEN SCREEN.
A1AE  A4AB                LDY     XTEMP

A1B0  60          :GS090  RTS


A1B1                      PROC
                  ;
                  ; 'DRAWTO', 'FILLTO' & 'GOTO' SUB-COMMAND PROCESSORS.
                  ;
A1B1  A912        GFILTO  LDA     #FILLTO         ; PEN DOWN.
A1B3  D006 ^A1BB          BNE     :GG005          ; (BRA).

A1B5  A90A        GDRWTO  LDA     #DRAWTO         ; PEN DOWN.
A1B7  D002 ^A1BB          BNE     :GG005          ; (BRA).

A1B9  A906        GGOTO   LDA     #GOTO           ; PEN UP.

A1BB  8DD405      :GG005  STA     GROPR           ; SET PEN POSITION.
A1BE  20D49F              JSR     EXP             ; GET X-COORDINATE.

A1C1  A592                LDA     EXEC            ; EXECUTE MODE?
A1C3  F008 ^A1CD          BEQ     :GG010          ; NO.

A1C5  A593                LDA     EXPSTK          ; YES -- UPDATE X.
A1C7  85E6                STA     GXNEW
A1C9  A594                LDA     EXPSTK+1
A1CB  85E7                STA     GXNEW+1

A1CD  20079F      :GG010  JSR     SKPSEP          ; SKIP OPERAND SEPARATOR.
A1D0  20D49F              JSR     EXP             ; GET Y-COORDINATE.

A1D3  A592                LDA     EXEC            ; EXECUTE MODE?
A1D5  F011 ^A1E8          BEQ     :GG090          ; NO.

A1D7  A593                LDA     EXPSTK          ; YES -- UPDATE Y.
A1D9  85E9                STA     GYNEW
A1DB  A594                LDA     EXPSTK+1
A1DD  85EA                STA     GYNEW+1

                  ; *** EXTERNAL ENTRY POINT FROM 'GHOME' ***

A1DF  A900        GGT030  LDA     #0              ; CLEAR FRACTIONAL PORTION OF X & Y.
A1E1  85E8                STA     GXNEW+2
A1E3  85EB                STA     GYNEW+2

A1E5  207AA6              JSR     GMOVE           ; NOW EFFECT MOVE.

A1E8              GGO090
A1E8              GTR090
A1E8              GTT090
A1E8  60          :GG090  RTS                     ; RETURN.


A1E9                      PROC
A1E9  20D49F      GTRNTO  JSR     EXP             ; GET POLAR ANGLE.

A1EC  A592                LDA     EXEC            ; EXECUTE MODE?
A1EE  F0F8 ^A1E8          BEQ     GTT090          ; NO.

A1F0  A593                LDA     EXPSTK          ; YES -- UPDATE POLAR ANGLE.
A1F2  85F2                STA     THETA
A1F4  A594                LDA     EXPSTK+1
A1F6  85F3                STA     THETA+1

A1F8  4C96AB              JMP     MOD360          ; MODULO 360 & RETURN

A1FB                      PROC
A1FB  A909        GBK     LDA     #DRAW           ; BK N = FD-N.
A1FD  8DD405              STA     GROPR
A200  20D49F              JSR     EXP             ; GET MAGNITUDE OF MOVE
A203  A213                LDX     #EXPSTK-DTAB    ; NEGATE IT.
A205  20F19C              JSR     DNEGI
A208  4C1BA2              JMP     :GG010          ; GO TO COMMON CODE.

A20B  A911        GFIL    LDA     #FILL           ; PEN DOWN
A20D  D006 ^A215          BNE     :GG005

A20F  A909        GDRW    LDA     #DRAW           ; PEN DOWN.
A211  D002 ^A215          BNE     :GG005

A213  A905        GGO     LDA     #GO             ; PEN UP.

A215  8DD405      :GG005  STA     GROPR           ; SET PEN POSITION.
A218  20D49F              JSR     EXP             ; GET MAGNITUDE OF MOVE.

A21B  A592        :GG010  LDA     EXEC            ; EXECUTE MODE?
A21D  F0C9 ^A1E8          BEQ     GGO090          ; NO.

A21F  2032A2              JSR     CALDEL          ; CALCULATE GXNEW & GYNEW.
A222  207AA6              JSR     GMOVE           ; NOW EFFECT MOVE.

A225  ADC505              LDA     RBTON           ; IS ROBOT TURTLE ON?
A228  F007 ^A231          BEQ     :GG090          ; NO.

A22A  84AB                STY     XTEMP           ; SAVE INDEX.
A22C  20D7B3              JSR     RGO             ; MOVE ROBOT ALSO.
A22F  A4AB                LDY     XTEMP           ; RESTORE INDEX.

A231  60          :GG090  RTS

A232  A901        CALDEL  LDA     #1              ; COS(THETA) = SIN(THETA+90).
A234  203BAD              JSR     SINVAL          ; GYNEW = GYNEW + (<EXP> * COS(THETA)).
A237  20F6AD              JSR     TMULT
A23A  A269                LDX     #GYNEW-DTAB
A23C  2044AE              JSR     TADDI

A23F  A900                LDA     #0
A241  203BAD              JSR     SINVAL          ; GXNEW = GXNEW + (<EXP> * SIN(THETA)).
A244  20F6AD              JSR     TMULT
A247  A266                LDX     #GXNEW-DTAB
A249  4C44AE              JMP     TADDI

A24C                      PROC
A24C  20D49F      GLT     JSR     EXP             ; LT N = RT -N.
A24F  A213                LDX     #EXPSTK-DTAB
A251  20F19C              JSR     DNEGI
A254  4C5AA2              JMP     :GT010          ; GO TO COMMON CODE.

A257  20D49F      GTRN    JSR     EXP             ; POLAR ANGLE DELTA THETA.

A25A  A592        :GT010  LDA     EXEC            ; EXECUTE MODE?
A25C  F08A ^A1E8          BEQ     GTR090          ; NO.

A25E  84AB                STY     XTEMP           ; YES -- SAVE INDEX.
A260  A272                LDX     #THETA-DTAB     ; THETA = THETA + DELTA.
A262  A013                LDY     #EXPSTK-DTAB
A264  20329C              JSR     DADDI

A267  2096AB              JSR     MOD360          ; MODULO 360.

A26A  ADC505              LDA     RBTON           ; IS ROBOT TURTLE ON?
A26D  F003 ^A272          BEQ     :GT090          ; NO.
A26F  20F9B3              JSR     RTURN           ; MOVE ROBOT ALSO.

A272  A4AB        :GT090  LDY     XTEMP
A274  60                  RTS

A275                      PROC
                  ;
                  ; GPEN -- GRAPHICS 'PEN' SUBCOMMAND
                  ;

A275  2096A4      GPEN    JSR     CLRMAT          ; SEE IF COLOR MATCH.
A278  D02E ^A2A8          BNE     :GP099          ; NO -- ERROR.

A27A  8DB805              STA     PENCOL          ; SAVE COLOR REGISTER VALUE.
A27D  A592                LDA     EXEC            ; EXECUTE MODE?
A27F  F026 ^A2A7          BEQ     :GP090          ; NO.

A281  B010 ^A293          BCS     :GP040          ; YES -- JIF 'UP', 'DOWN ' OR 'ERASE'.

A283  8A                  TXA                     ; IS COLOR ALREADY AVAILABLE?
A284  1008 ^A28E          BPL     :GP030          ;  YES.

A286  ADB805              LDA     PENCOL          ; NO -- FIND VACANT SLOT FOR NEW COLOR.
A289  20DEA4              JSR     CASSGN
A28C  D01A ^A2A8          BNE     :GP099          ; NO FREE SLOTS.

A28E  8A          :GP030  TXA                     ; MERGE PEN UP/DOWN STATUS WITH ...
      = 0000              IF      FALSE
   -                      EOR     PEN             ; ... NEW PIXEL VALUE.
   -                      AND     #$7F
   -                      EOR     PEN
                          ENDIF
A28F  8D1305              STA     PEN
A292  60                  RTS

A293  8A          :GP040  TXA
A294  F0F8 ^A28E          BEQ     :GP030          ; 'ERASE'.

A296  1007 ^A29F          BPL     :GP050          ; 'DOWN'.

A298  0D1305              ORA     PEN             ; 'UP'.
A29B  8D1305              STA     PEN
A29E  60                  RTS

A29F  AD1305      :GP050  LDA     PEN             ; 'DOWN'.
A2A2  297F                AND     #$FF-PCUP
A2A4  8D1305              STA     PEN

A2A7  60          :GP090  RTS

A2A8  4C3A7A      :GP099  JMP     PSTOP

A2AB  A592        GPU     LDA     EXEC            ;  PEN UP.
A2AD  F0F8 ^A2A7          BEQ     :GP090

A2AF  A280                LDX     #PCUP
A2B1  4C93A2              JMP     :GP040

A2B4  A592        GPD     LDA     EXEC            ; PEN DOWN.
A2B6  F0EF ^A2A7          BEQ     :GP090

A2B8  A240                LDX     #PCDN
A2BA  4C93A2              JMP     :GP040

A2BD  A592        GPE     LDA     EXEC            ; PEN ERASE.
A2BF  F0E6 ^A2A7          BEQ     :GP090

A2C1  A200                LDX     #0
A2C3  4C93A2              JMP     :GP040

A2C6                      PROC
                  ;
                  ; GBACK -- GRAPHICS 'BACKGROUND' SUBCOMMAND
                  ;

A2C6  2096A4      GBACK   JSR     CLRMAT          ; SEE IF COLOR MATCH.
A2C9  D014 ^A2DF          BNE     :GB099          ; NO -- ERROR.

A2CB  B010 ^A2DD          BCS     :GB092          ; JIF 'UP', 'DOWN' OR 'ERASE'.

A2CD  8DB805              STA     PENCOL          ; YES -- SAVE COLOR VALUE.
A2D0  A592                LDA     EXEC            ; EXECUTE MODE?
A2D2  F008 ^A2DC          BEQ     :GB090          ; NO.

A2D4  A200                LDX     #0              ; INDEX FOR BACKGROUND.
A2D6  ADB805              LDA     PENCOL          ; COLOR REGISTER VALUE.
A2D9  20F7A4              JSR     SETCLR          ; SET 'PNCLRS' AND COLOR REGISTER.

A2DC  60          :GB090  RTS

A2DD  A902        :GB092  LDA     #IMPERR         ; OPERAND ERROR.

A2DF  4C3A7A      :GB099  JMP     PSTOP

A2E2                      PROC
                  ;
                  ; GCHNGE -- GRAPHICS 'CHANGE' SUBCOMMAND
                  ;

A2E2  2096A4      GCHNGE  JSR     CLRMAT          ; GET "FROM" OPERAND.
A2E5  D030 ^A317          BNE     :GC099          ; ERROR.

A2E7  B023 ^A30C          BCS     :GC092          ; 'UP', 'DOWN' OR 'ERASE' INVALID.

A2E9  A592                LDA     EXEC            ; EXECUTE MODE?
A2EB  F003 ^A2F0          BEQ     :GC020          ; NO.

A2ED  8A                  TXA                     ; SEE IF "FROM" COLOR EXISTS.
A2EE  301C ^A30C          BMI     :GC092          ; NO -- ERROR.

A2F0  8EB705      :GC020  STX     PENNUM          ; YES -- SAVE PEN NUMBER.

A2F3  20079F              JSR     SKPSEP
A2F6  2096A4              JSR     CLRMAT          ; GET "TO" COLOR OPERAND.
A2F9  D01C ^A317          BNE     :GC099          ; ERROR.

A2FB  B00F ^A30C          BCS     :GC092          ; 'UP', 'DOWN' OR 'ERASE' INVALID.

A2FD  E0FF                CPX     #$FF            ; CHECK FOR DOUBLE ASSIGN AFTER CHG
A2FF  D010 ^A311          BNE     :GC094          ; DOUBLE ASSIGN -- ERROR.

A301  A692                LDX     EXEC            ; EXECUTE MODE?
A303  F006 ^A30B          BEQ     :GC090          ; NO.

A305  AEB705              LDX     PENNUM          ; GET PEN NUMBER.
A308  20F7A4              JSR     SETCLR          ; SET 'PNCLRS' AND COLOR REGISTER

A30B  60          :GC090  RTS

A30C  A902        :GC092  LDA     #IMPERR         ; INVALID OPERAND.
A30E  4C3A7A              JMP     PSTOP

A311  A592        :GC094  LDA     EXEC            ; NO PROBLEM IF NOT EXECUTE.
A313  F0F6 ^A30B          BEQ     :GC090

A315  A926                LDA     #DCAERR         ; DOUBLE ASSIGN.

A317  4C3A7A      :GC099  JMP     PSTOP


A31A                      PROC
                  ;
                  ; GSHADE -- GRAPHICS 'SHADE' SUBCOMMAND.
                  ;
A31A  2096A4      GSHADE  JSR     CLRMAT          ; MATCH OPERAND.
A31D  D031 ^A350          BNE     :GS099          ; NO MATCH.

A31F  B02A ^A34B          BCS     :GS092          ; 'UP', 'DOWN' OR 'ERASE'.

A321  8DB805              STA     PENCOL          ; SAVE PEN COLOR.
A324  A592                LDA     EXEC            ; EXECUTE MODE?
A326  F022 ^A34A          BEQ     :GS090          ; NO.

A328  8A                  TXA
A329  1008 ^A333          BPL     :GS030          ; COLOR ASSIGNED.

A32B  ADB805              LDA     PENCOL
A32E  20DEA4              JSR     CASSGN          ; COLOR NOT ASSIGNED -- DO SO.
A331  D01D ^A350          BNE     :GS099          ; NO FREE SLOT.

A333  8E9B05      :GS030  STX     FCOLOR          ; SAVE FILL COLOR.

A336  205EAC              JSR     GREAD           ; CHECK FOR IN BOUNDS.
A339  B00F ^A34A          BCS     :GS090          ; TURTLE OUT OF BOUNDS.

A33B  84AB                STY     XTEMP
A33D  2098AF              JSR     FLOOD           ; SHADE THE AREA.
A340  A03E                LDY     #GX1-DTAB       ; RESTORE VISIBLE TURTLE TO PROPER
A342  20FFAB              JSR     SETCUR
A345  209FAA              JSR     CNVRT
A348  A4AB                LDY     XTEMP

A34A  60          :GS090  RTS

A34B  8A          :GS092  TXA
A34C  F0E5 ^A333          BEQ     :GS030          ; 'ERASE' OK.

A34E  A902                LDA     #IMPERR
A350  4C3A7A      :GS099  JMP     PSTOP
A353                      PROC
                  ;
                  ; GWALL -- WALL SUBCOMMAND PROCESSOR.
                  ;
A353  A212        GWALL   LDX     #WLTABX         ; 'NONE'?
A355  20AB7C              JSR     SBCMAT
A358  D00D ^A367          BNE     :GW010          ; NO.

A35A  A592                LDA     EXEC            ; EXECUTE MODE?
A35C  F008 ^A366          BEQ     :GW009          ; NO.

A35E  A900                LDA     #0              ; YES -- CLEAR WALLS.
A360  8DCD05              STA     WALLS
A363  8DCE05              STA     WALLS+1

A366  60          :GW009  RTS

A367  2096A4      :GW010  JSR     CLRMAT          ; PEN/COLOR SELECTION?
A36A  D020 ^A38C          BNE     :GW092          ; NO.

A36C  B01E ^A38C          BCS     :GW092          ; YES -- JIF 'UP', 'DOWN' OR 'ERASE'.

A36E  A592                LDA     EXEC            ; EXECUTE MODE?
A370  F019 ^A38B          BEQ     :GW090          ; NO.

A372  8A                  TXA
A373  3017 ^A38C          BMI     :GW092          ; COLOR NOT ASSIGNED TO A PEN.

A375  F015 ^A38C          BEQ     :GW092          ; BACKGROUND CAN'T BE A WALL.

A377  0A                  ASL     A
A378  AA                  TAX
A379  BD3EAC              LDA     WMASK,X
A37C  0DCD05              ORA     WALLS
A37F  8DCD05              STA     WALLS
A382  BD3FAC              LDA     WMASK+1,X
A385  0DCE05              ORA     WALLS+1
A388  8DCE05              STA     WALLS+1

A38B  60          :GW090  RTS

A38C  A902        :GW092  LDA     #IMPERR
A38E  4C3A7A              JMP     PSTOP


A391                      PROC
                  ;
                  ; GEXIT -- GRAPHICS 'QUIT' SUBCOMMAND.
                  ;

A391  A592        GEXIT   LDA     EXEC            ; EXECUTE MODE?
A393  F00A ^A39F          BEQ     :GE090          ; NO.

A395  84AB                STY     XTEMP
A397  2074B3              JSR     RBTOFF          ; 'ROBOT TURTLE' OFF.
A39A  20F494              JSR     TXOPEN          ; OPEN TEXT MODE SCREEN.
A39D  A4AB                LDY     XTEMP
A39F              GHM090
A39F              GCL090
A39F  60          :GE090  RTS

A3A0                      PROC
                  ;
                  ; GCLEAR -- GRAPHICS 'CLEAR' SUBCOMMAND.
                  ;
                  ; *** CALLED BY 'XRUN' TOO ***

A3A0  A592        GCLEAR  LDA     EXEC            ; EXECUTE MODE?
A3A2  F0FB ^A39F          BEQ     GCL090          ; NO.

A3A4  A900                LDA     #0              ; TO AVOID ERROR $80 IF CURSOR AT LOWER ...
A3A6  8554                STA     ROWCRS          ; ... RIGHT CORNER OF SCREEN.

A3A8  A97D                LDA     #CLEAR          ; YES -- CLEAR GRAPHICS SCREEN ...
A3AA  4C8097              JMP     TOUT            ; ... & RETURN.

A3AD                      PROC
                  ;
                  ; GCLRPN -- GRAPHICS 'CLEARPENS'.
                  ;
A3AD  A592        GCLRPN  LDA     EXEC            ; EXECUTE MODE?
A3AF  F0EE ^A39F          BEQ     GCL090          ; NO.

A3B1  A901                LDA     #1              ; YES -- CLEAR PEN SELECTS.
A3B3  8DBA05              STA     NXTCLR
A3B6  60                  RTS


A3B7                      PROC
                  ; GHOME -- TURTLE HOME

A3B7  A592        GHOME   LDA     EXEC            ; EXECUTE MODE?
A3B9  F0E4 ^A39F          BEQ     GHM090          ; NO.

A3BB  A900                LDA     #0              ; YES -- SET TURTLE X & Y TO ZERO.
A3BD  85E6                STA     GXNEW
A3BF  85E7                STA     GXNEW+1
A3C1  85E9                STA     GYNEW
A3C3  85EA                STA     GYNEW+1
A3C5  A906                LDA     #GOTO
A3C7  8DD405              STA     GROPR           ; GOTO TYPE.
A3CA  4CDFA1              JMP     GGT030

A3CD                      PROC
                  ; GNORTH -- TURTLE NORTH

A3CD  A592        GNORTH  LDA     EXEC            ; EXECUTE MODE?
A3CF  F009 ^A3DA          BEQ     :GN090          ; NO,.

A3D1  A900                LDA     #0              ; YES -- SET THETA TO ZERO.
A3D3  85F2                STA     THETA
A3D5  85F3                STA     THETA+1
A3D7  2096AB              JSR     MOD360

A3DA  60          :GN090  RTS

A3DB                      PROC
                  ;
                  ; GEDGE -- 'EDGE' SUBCOMMAND
                  ;
A3DB  A20E        GEDGE   LDX     #EDTABX         ; 'FREE', 'HALT', WRAP', OR 'BOUNCE'.
A3DD  20AB7C              JSR     SBCMAT
A3E0  D016 ^A3F8          BNE     :GE099          ; NO MATCH.

A3E2  A592                LDA     EXEC            ; EXECUTE MODE?
A3E4  F011 ^A3F7          BEQ     :GE090          ; NO.

A3E6  8E5E05              STX     EDGRUL          ; YES -- SET RULE SELECT.
A3E9  E008                CPX     #EFREE          ; RULE = FREE?
A3EB  F00A ^A3F7          BEQ     :GE090          ; YES.

A3ED  A26C                LDX     #GX-DTAB        ; TURTLE IN SCREEN BOUNDS?
A3EF  200DAB              JSR     INTEST
A3F2  F003 ^A3F7          BEQ     :GE090          ; YES.

A3F4  20B7A3              JSR     GHOME           ; NO -- SEND TURTLE HOME.

A3F7  60          :GE090  RTS

A3F8  4C3A7A      :GE099  JMP     PSTOP

A3FB                      PROC
                  ; GTURTL -- TURTLE ON/OFF

A3FB  A20A        GTURTL  LDX     #ONOFFX         ; EXPECT 'ON' OR 'OFF'
A3FD  20AB7C              JSR     SBCMAT
A400  D014 ^A416          BNE     :GT100          ; NO MATCH - SEE IF COLOR.

A402  A592                LDA     EXEC            ; EXECUTE MODE?
A404  F00A ^A410          BEQ     :GT090          ; NO.

A406  8E4F05      :GT020  STX     TRTLON          ; YES -- SET TURTLE FLAG.
A409  84AB                STY     XTEMP           ; SAVE INDEX.
A40B  200CA6              JSR     TRONOF          ; DEAL WITH TURTLE REP.
A40E  A4AB                LDY     XTEMP           ; RESTORE INDEX.

A410  60          :GT090  RTS

A411  A902        :GT092  LDA     #IMPERR

A413  4C3A7A      :GT099  JMP     PSTOP

A416  2096A4      :GT100  JSR     CLRMAT          ; COLOR SELECTION?
A419  D0F8 ^A413          BNE     :GT099          ; NO -- ERROR.

A41B  B0F4 ^A411          BCS     :GT092          ; JIF 'UP', 'DOWN', OR 'ERASE'.

A41D  A692                LDX     EXEC            ; EXECUTE MODE?
A41F  F0EF ^A410          BEQ     :GT090          ; NO.
A421  8DC405              STA     TRTCOL          ; YES -- UPDATE TURTLE COLOR.
A424  D0E0 ^A406          BNE     :GT020          ; (BRA) WITH X <> 0.


A426                      PROC
                  ;
                  ; XSETP -- 'SETPEN' COMMAND PROCESSOR
                  ; XSETL -- 'SETLET' COMMAND PROCESSOR
                  ;
A426  F012 ^A43A  XSETL   BEQ     :SP010          ; SYNTAX SCAN ONLY.

A428  20BB96              JSR     TSTMOD          ; LETTERS MEDIUM OR LARGE?
A42B  C902                CMP     #TXML
A42D  D064 ^A493          BNE     :SP094          ; NO -- ERROR.

A42F  F009 ^A43A          BEQ     :SP010          ; (BRA) TO COMMON CODE.


A431  F007 ^A43A  XSETP   BEQ     :SP010          ; SYNTAX SCAN ONLY.

A433  20BB96              JSR     TSTMOD          ; GRAPHICS MODE?
A436  290C                AND     #GRSS+GRFS
A438  F059 ^A493          BEQ     :SP094          ; NO -- ERROR.

A43A  20BDA4      :SP010  JSR     CLM040          ; GET PEN NUMBER.
A43D  D050 ^A48F          BNE     :SP090          ; ERROR.

A43F  8EB705              STX     PENNUM          ; SAVE PEN NUMBER.

A442  20079F              JSR     SKPSEP          ; SEE IF ALPHA -- IF SO CALL CLRMAT
A445  B180                LDA     (INLN),Y
A447  20919E              JSR     CLETTR          ; ALPHA CHARACTER?
A44A  B00D ^A459          BCS     :SP012          ; NO -- SHOULD BE NEXP.

A44C  2096A4              JSR     CLRMAT          ; YES -- SEE IF COLOR NAME?
A44F  D03E ^A48F          BNE     :SP090          ; NO -- ERROR.
A451  B03D ^A490          BCS     :SP092          ; NO -- 'UP', 'DOWN' OR 'ERASE'.

A453  A692                LDX     EXEC            ; EXECUTE MODE?
A455  F038 ^A48F          BEQ     :SP090          ; NO.

A457  902E ^A487          BCC     :SP030          ; VALID COLOR.

A459  20D49F      :SP012  JSR     EXP             ; GET HUE VALUE.
A45C  A592                LDA     EXEC            ; EXECUTE MODE?
A45E  F010 ^A470          BEQ     :SP020          ; NO.

A460  A594                LDA     EXPSTK+1
A462  D02C ^A490          BNE     :SP092          ; OUT OF RANGE. #

A464  A593                LDA     EXPSTK
A466  C910                CMP     #$10
A468  B026 ^A490          BCS     :SP092          ; OUT OF RANGE.

A46A  0A                  ASL     A               ; JUSTIFY THE HUE VALUE.
A46B  0A                  ASL     A
A46C  0A                  ASL     A
A46D  0A                  ASL     A
A46E  85AB                STA     XTEMP           ; SAVE ADJUSTED VALUE.

A470  20079F      :SP020  JSR     SKPSEP
A473  20D49F              JSR     EXP             ; GET LUM VALUE.
A476  A592                LDA     EXEC            ; EXECUTE MODE?
A478  F015 ^A48F          BEQ     :SP090          ; NO.

A47A  A594                LDA     EXPSTK+1
A47C  D012 ^A490          BNE     :SP092          ; OUT OF RANGE.

A47E  A593                LDA     EXPSTK
A480  C908                CMP     #8
A482  B00C ^A490          BCS     :SP092          ; OUT OF RANGE.

A484  0A                  ASL     A               ; X2.
A485  05AB                ORA     XTEMP           ; MERGE HUE WITH LUM.

A487  AEB705      :SP030  LDX     PENNUM          ; GET PEN NUMBER.
A48A  20F7A4              JSR     SETCLR          ; SET 'PNCLRS' AND COLOR REGISTER.
A48D  A900                LDA     #0              ; SET CC FOR NORMAL RETURN.

A48F  60          :SP090  RTS                     ; RETURN WITH CC SET.

A490  A902        :SP092  LDA     #IMPERR
A492  60                  RTS

A493  A983        :SP094  LDA     #NRCERR
A495  60                  RTS

A496                      PROC
                  ;
                  ; CLRMAT -- COLOR MATCHER
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'INLN' = POINTER TO STATEMENT.
                  ;       Y = STATEMENT INDEX.
                  ;
                  ;       JSR CLRNAT
                  ;       BNE ERROR
                  ;
                  ;       C = 1 INDICATES X = 'PCUP', 'PCDN' OR 0.
                  ;       C = 0 INDICATES A = COLOR REGISTER VALUE.
                  ;                       X = -1 IF NOT IN 'PNCLRS', OR
                  ;                       X = PIXEL VALUE ('PNCLRS' SLOT #).
                  ;
A496  A206        CLRMAT  LDX     #PCTABX         ; MATCH OPERAND.
A498  20AB7C              JSR     SBCMAT
A49B  D020 ^A4BD          BNE     :CM040          ; NO MATCH -- SEE IF NEXP

A49D  E080                CPX     #PCUP           ; CHECK FOR 'UP', 'DOWN', OR 'ERASE'.
A49F  F038 ^A4D9          BEQ     :CM080          ; 'UP'.

A4A1  E040                CPX     #PCDN           ; 'DOWN'.
A4A3  F034 ^A4D9          BEQ     :CM080

A4A5  8A                  TXA

A4A6  F031 ^A4D9          BEQ     :CM080          ; 'ERASE'.

A4A8  A200                LDX     #0              ; SEARCH 'PNCLRS' FOR VALUE PATCH.

A4AA  E8          :CM010  INX
A4AB  ECBA05              CPX     NXTCLR
A4AE  B007 ^A4B7          BCS     :CM020          ; END OF VALID ENTRIES.

A4B0  DDBB05              CMP     PNCLRS,X        ; COLOR VALUE MATCH?
A4B3  D0F5 ^A4AA          BNE     :CM010          ; NO.

A4B5  18                  CLC                     ; YES -- INDICATF COLOR VALUE O.K.
A4B6  60                  RTS                     ; RETURN WITH CC SET.

A4B7  A2FF        :CM020  LDX     #$FF            ;  INDICATE NOT FOUND.

A4B9  E0FF                CPX     #$FF            ; SET CC.
A4BB  18                  CLC                     ; INDICATE COLOR VALUE O.K.
A4BC  60                  RTS                     ; RETURN WITH CC SET.

                  ; *** EXTERNAL ENTRY POINT FROM 'XSETP' & ' XSETL ' ***

A4BD              :CM040
A4BD  20D49F      CLM040  JSR     EXP             ; PROCESS AS A NUMERIC EXPRESSION.
A4C0  A592                LDA     EXEC            ; EXECUTE MODE?
A4C2  F00D ^A4D1          BEQ     :CM050          ; NO.

A4C4  A694                LDX     EXPSTK+1
A4C6  D013 ^A4DB          BNE     :CM092          ; OUT OF RANGE.

A4C8  A693                LDX     EXPSTK
A4CA  ECB905              CPX     NCOLRS          ; IS VALUE IN RANGE?
A4CD  F002 ^A4D1          BEQ     :CM050          ; YES.
A4CF  B00A ^A4DB          BCS     :CM092          ; NO.

A4D1  BDBB05      :CM050  LDA     PNCLRS,X        ; YES -- GET COLOR VALUE.
A4D4  DDBB05              CMP     PNCLRS,X        ; SET CC FOR EXIT.
A4D7  18                  CLC                     ; INDICATE PEN NUMBER O.K.
A4D8  60                  RTS                     ; RETURN WITH CC SET.

A4D9  38          :CM080  SEC                     ; X = 'PCUP' OR 'PCDN' OR 0.
A4DA  60                  RTS                     ; RETURN WITH CC SET.

A4DB  A902        :CM092  LDA     #IMPERR         ; OUT OF RANGE PEN NUMBER.
A4DD  60                  RTS

A4DE                      PROC
                  ;
                  ; CASSGN -- COLOR ASSIGNMENT
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       A = COLOR REGISTER VALUE
                  ;       GSMODE = GRAPHICS MODE
                  ;       NXTCLR = NEXT AVAILABLE SLOT NUMBER
                  ;       NCOLRS = LAST SLOT NUMBER
                  ;
                  ;       JSR     CASSGN
                  ;       BNE     ERROR
                  ;
                  ;       X = PEN NUMBER
                  ;
A4DE  AEBA05      CASSGN  LDX     NXTCLR          ; GET NEXT SLOT NUMBER.
A4E1  ECB905              CPX     NCOLRS          ; USEABLE SLOT?
A4E4  F002 ^A4E8          BEQ     :CN005          ; YES.
A4E6  B00C ^A4F4          BCS     :CN092          ; NO MORE SLOTS.

A4E8  20F7A4      :CN005  JSR     SETCLR          ; ASSIGN COLOR TO PEN & COLOR REG.
A4EB  AEBA05              LDX     NXTCLR
A4EE  EEBA05              INC     NXTCLR

A4F1  A900                LDA     #0              ; SET CC FOR NORMAL EXIT.
A4F3  60                  RTS

A4F4  A925        :CN092  LDA     #NMCERR         ; NO MORE PEN SLOTS.
A4F6  60                  RTS

A4F7                      PROC
                  ;
                  ; SETCLR -- SET COLOR
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       A = COLOR REGISTER VALUE.
                  ;       X = PEN NUMBER (PIXEL VALUE).
                  ;       GSMODE = GRAHICS MODE.
                  ;
                  ;       JSR     SETCLR
                  ;

A4F7  9DBB05      SETCLR  STA     PNCLRS,X        ; FIRST SET PIXEL VAL IN TABLE.
A4FA  8CCB05              STY     SCTEMP
A4FD  48                  PHA                     ; SAVE COLOR VALUE.
A4FE  8A                  TXA                     ; PIXEL VALUE TO Y REGISTER.
A4FF  A8                  TAY
A500  AD3705              LDA     GSMODE
A503  0A                  ASL     A               ; X2
A504  AA                  TAX
A505  BD60BA              LDA     COLADR,X        ; GET POINTER TO REGISTER SET.
A508  85F4                STA     FSTACK
A50A  BD61BA              LDA     COLADR+1,X
A50D  85F5                STA     FSTACK+1
A50F  B1F4                LDA     (FSTACK),Y      ; GET COLOR REGISTER INDEX.
A511  AA                  TAX
A512  68                  PLA
A513  9DC002              STA     PCOLR0,X        ; STORE COLOR VALUE TO REGISTER.
A516  ACCB05              LDY     SCTEMP
A519  60                  RTS

A51A                      PROC
                  ;
                  ; PRCLNM -- FIND AND FRINT COLOR NAME
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = INDEX TO 'PNCLRS'
                  ;
                  ;       JSR     PRCLNM
                  ;
A51A  BDBB05      PRCLNM  LDA     PNCLRS,X        ; GET COLOR REGISTER VALUE.
A51D  85A9                STA     TEMP2+2
A51F  8ECC05              STX     PRTEMP          ; SAVE X REGISTER.
A522  A2FF                LDX     #-1             ; SETUP TO SCAN THE NAME TABLE.

A524  E8          :PC010  INX
A525  86A8                STX     TEMP2+1         ; SAVE INDEX TO START OF NAME.

A527  BD707F      :PC015  LDA     PCTAB,X         ; GET A CHARACTER.
A52A  F016 ^A542          BEQ     :PC080          ; END OF TABLE -- NO MATCH.

A52C  3003 ^A531          BMI     :PC020          ; FOUND THE # SB' BYTE.

A52E  E8                  INX                     ; STILL INSIDE THE NAME.
A52F  D0F6 ^A527          BNE     :PC015          ; (BRA).

A531  E8          :PC020  INX                     ; BUMP TO THE VALUE BYTE.
A532  BD707F              LDA     PCTAB,X         ; GET THE VALUE.
A535  C5A9                CMP     TEMP2+2         ; IS THIS THE ONE WE ARE LOOKING FOR?
A537  D0EB ^A524          BNE     :PC010          ; NO.

A539  A6A8                LDX     TEMP2+1         ; YES -- GET INDEX TO NAME.
A53B  204FA5              JSR     PRNTCL          ; PRINT COLOR NAME.

A53E  AECC05              LDX     PRTEMP          ; RESTORE X REGISTER.
A541  60                  RTS

A542  A900        :PC080  LDA     #0              ; NO NAME -- PRINT THE NUMERIC VALUE.
A544  85AA                STA     TEMP2+3         ; ZERO THE MSB FIRST.
A546  A229                LDX     #TEMP2+2-DTAB   ; POINT TO NUMBER.
A548  20149E              JSR     DECASC

A54B  AECC05              LDX     PRTEMP          ; RESTORE X REGISTER.
A54E  60                  RTS

A54F                      PROC
                  ;
                  ; PRNTCL -- PRINT COLOR NAME FROM NAME TABLE.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = INDEX TO FIRST CHARACTER OF COLOR NAME.
                  ;
                  ;       JSR     PRNTCL
                  ;
                  ;       X = INDEX TO NAME DELIMITER.
                  ;
A54F  BD707F      PRNTCL  LDA     PCTAB,X         ; GET A CHARACTER.
A552  3006 ^A55A          BMI     :PC090          ; DELIMITER.
A554  208294              JSR     CHOT
A557  E8                  INX
A558  D0F5 ^A54F          BNE     PRNTCL          ; (BRA).
A55A  60          :PC090  RTS



A55B                      PROC
A55B  A26C        TRTPLC  LDX     #GX-DTAB        ; TURTLE IN BOUNDS?
A55D  200DAB              JSR     INTEST
A560  F008 ^A56A          BEQ     :TR090          ; YES.

A562  A9FF                LDA     #-1             ; NO -- SET FLAG.
A564  8DD005              STA     GCOL+1
A567  206BA5              JSR     CLRTRT          ; CLEAR OLD TURTLE.

A56A  60          :TR090  RTS

A56B  AE5F05      CLRTRT  LDX     TRYPOS          ; GET OLD POSITION.
A56E  A00E                LDY     #VTHITE
A570  A900                LDA     #0

A572  9D0577      :TP020  STA     TRBUFF,X        ; REMOVE OLD REPRESENTATION.
A575  E8                  INX
A576  88                  DEY
A577  D0F9 ^A572          BNE     :TP020

A579  60                  RTS


A57A                      PROC
                  ;
                  ; TRTLOC -- PLACE VISIBLE TURTLE (AT NEW LOC).
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'TUFLAG'      = 0 IF GCOL & GROW O.K.
                  ;       'TRTLON'      = 0 IF OFF, ELSE ON.
                  ;       'GSMODE'      = GRAPHICS SCREEN MODE.
                  ;       'THETA'       = TURTLE ANGLE.
                  ;       'GCOL'        = TURTLE X POSITION.
                  ;       'GROW'        = TURTLE Y POSITION.
                  ;
                  ;       JSR     TRTLOC
                  ;
A57A  AD4F05      TRTLOC  LDA     TRTLON          ; TURTLE ON?
A57D  F061 ^A5E0          BEQ     :TP100          ; NO.

A57F  ADD905              LDA     TUFLAG          ; ARE FARMS VALID?
A582  D05C ^A5E0          BNE     :TP100          ; NOT NECESSARILY.

A584  ADD005              LDA     GCOL+1          ; IN SCREEN BOUND?
A587  3057 ^A5E0          BMI     :TP100          ; NO.

A589  206BA5              JSR     CLRTRT          ; CLEAR OLD TURTLE.
A58C  2039A6              JSR     DUMCAL          ; CALCULATE ORIENTATION.

                  ; CONVERT CURSOR X TO COLOR CLOCKS.

A58F  AE3705              LDX     GSMODE          ; SCREEN MODE DEPENDENT
A592  BC9CB8              LDY     CCPXTB,X        ; GET # OF COLOR CLOCKS PER X UNIT
A595  F00C ^A5A3          BEQ     :TP040          ; ZERO INDICATES 1/2 CLOCK.

A597  98                  TYA                     ; START WITH 1/2 POSITION OFFSET.
A598  18                  CLC
A599  6A                  ROR     A
A59A  18                  CLC

A59B  6DCF05      :TP030  ADC     GCOL            ; NOW DO MULTIPLY.
A59E  88                  DEY
A59F  D0FA ^A59B          BNE     :TP030

A5A1  F008 ^A5AB          BEQ     :TP050          ; (BRA).

A5A3  ADD005      :TP040  LDA     GCOL+1          ; DIVIDE BY 2 (1/2 COLOR CLOCK).
A5A6  6A                  ROR     A
A5A7  ADCF05              LDA     GCOL
A5AA  6A                  ROR     A

A5AB  18          :TP050  CLC
A5AC  6930                ADC     #$30            ; LEFT EDGE OFFSET.
A5AE  AC6005              LDY     ORIENT          ; SUBTRACT ORIENTATION OFFSET.
A5B1  38                  SEC
A5B2  F9F8B8              SBC     TRDX,Y
A5B5  18                  CLC
A5B6  8D03D0              STA     HPOS0+3         ; RESULT IS PLAYER3 HORIZONTAL POSITION.

                  ; CONVERT CURSOR Y TO SCAN LINES

A5B9  BCACB8              LDY     SLPYTB,X        ; GET #SC AN LINES PERR Y UNIT.
A5BC  98                  TYA                     ; START WITH 1/2 POSITION OFFSET.
A5BD  18                  CLC
A5BE  6A                  ROR     A
A5BF  18                  CLC

A5C0  6DD105      :TP060  ADC     GROW            ; MULTIPLY.
A5C3  88                  DEY
A5C4  D0FA ^A5C0          BNE     :TP060

A5C6  6915                ADC     #$15            ; *** MAGIC OFFSET ***
A5C8  AC6005              LDY     ORIENT          ; SUBTRACT ORIENTATION OFFSET.
A5CB  38                  SEC
A5CC  F9E0B8              SBC     TRDY,Y
A5CF  8D5F05              STA     TRYPOS          ; SAVE FOR NEXT TIME IN.
A5D2  AA                  TAX                     ; SETUP FOR THIS TIME.
A5D3  A000                LDY     #0

A5D5  B1F8        :TP090  LDA     (TRADDR),Y      ; MOVE PATTERN TO MISSILE BUFFER
A5D7  9D0577              STA     TRBUFF,X
A5DA  E8                  INX
A5DB  C8                  INY
A5DC  C00E                CPY     #VTHITE
A5DE  D0F5 ^A5D5          BNE     :TP090

A5E0  60          :TP100  RTS

A5E1                      PROC
                  ; TRTINI -- VISIBLE TURTLE INITIALIZATION.


A5E1              TRTINI
A5E1  A2FD                LDX     #253            ; CLEAR TURTLE REPRESENTATION BUFFER.
A5E3  A900                LDA     #0
A5E5  8D5F05              STA     TRYPOS
A5E8  8DD905              STA     TUFLAG          ; INITIALIZE TURTLE LOC. INTERLOCK.
A5EB  8D0BD0              STA     SIZEP3          ; PLAYER SIZE.

A5EE  9D0277      :TI010  STA     TPBUFF+2,X
A5F1  CA                  DEX
A5F2  D0FA ^A5EE          BNE     :TI010

A5F4  A208                LDX     #8              ; INITIALIZE PLAYER/MISSILE HARDWARE.

A5F6  9DFFCF      :TI020  STA     HPOS0-1,X       ; SET ALL HORIZONTAL POSITION TO ZERO
A5F9  CA                  DEX
A5FA  D0FA ^A5F6          BNE     :TI020

A5FC  A901                LDA     #1              ; SET PRIORITY.
A5FE  8D6F02              STA     GPRIOR
A601  A970                LDA     # HIGH [TPBUFF-$700]    ; PLAYER/MISSILE BASE ADDRESS
A603  8D07D4              STA     PMBASE
A606  A902                LDA     #$02            ; DEFAULT TURTLE COLOR.
A608  8DC405              STA     TRTCOL

A60B  60                  RTS

A60C                      PROC
                  ; TRONOF -- MISSILE DMA ON/OFF.

A60C  AD4F05      TRONOF  LDA     TRTLON          ; TURTLE ON?
A60F  F017 ^A628          BEQ     :TF050          ; NO.

A611  ADC405              LDA     TRTCOL          ; YES -- SET PLAYER COLOR REG.
A614  8DC302              STA     PCOLR0+3

A617  A902                LDA     #2
A619  8D1DD0              STA     GRACTL

A61C  AD2F02              LDA     DMACT           ; ENABLE PLAYER DMA (HIGH RESOLUTION
A61F  0918                ORA     #$18
A621  8D2F02              STA     DMACT
A624  8D00D4              STA     DMACTL

A627  60                  RTS

A628  AD2F02      :TF050  LDA     DMACT           ; PLAYER DMA OFF.
A62B  29E7                AND     #$E7
A62D  8D2F02              STA     DMACT

A630  A900                LDA     #0
A632  8D1DD0              STA     GRACTL
A635  8D10D0              STA     GRAFP3

A638  60                  RTS


A639                      PROC
A639  ADD205      DUMCAL  LDA     GANGLE          ; TRADDR := GANGLE.
A63C  85F8                STA     TRADDR
A63E  ADD305              LDA     GANGLE+1
A641  85F9                STA     TRADDR+1
A643  A000                LDY     #0

A645  A278                LDX     #TRADDR-DTAB
A647  A9F8                LDA     #-8
A649  20049D              JSR     DADDS
A64C  A5F9                LDA     TRADDR+1
A64E  3010 ^A660          BMI     :DC020

A650  C8          :DC010  INY
A651  A9F1                LDA     #-15
A653  20049D              JSR     DADDS
A656  A5F9                LDA     TRADDR+1
A658  10F6 ^A650          BPL     :DC010
A65A  C018                CPY     #24

A65C  9002 ^A660          BCC     :DC020
A65E  A000                LDY     #0

A660  8C6005      :DC020  STY     ORIENT
A663  A9B9                LDA     # HIGH VTURT    ; SETUP POINTER TO TURTLE REP.
A665  85F9                STA     TRADDR+1
A667  A910                LDA     # LOW VTURT
A669  85F8                STA     TRADDR
A66B  C000                CPY     #0
A66D  F00A ^A679          BEQ     :DC090

A66F  A278                LDX     #TRADDR-DTAB

A671  A90E        :DC030  LDA     #VTHITE         ; CALCULATE OFFSET.
A673  20049D              JSR     DADDS
A676  88                  DEY
A677  D0F8 ^A671          BNE     :DC030

A679  60          :DC090  RTS

A67A                      PROC
                  ;
                  ; LOWER LEVEL GRAPHICS UTILITIES
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'GX' & 'GY' = START COORDINATES.
                  ;       'GXNEW' & 'GYNEW' = END COORDINATES.
                  ;
                  ;       JSR     GMOVE
                  ;
                  ;       'GX' = 'GXNEW' = END COORDINATES.
                  ;       'GY' = 'GYNEW' = END COORDINATES.
                  ;
A67A  84E0        GMOVE   STY     LEND              ; SAVE Y REGISTER.
A67C  A20C                LDX     #12             ; VARIABLES OF 3 BYTES EACH.

A67E  B5E5        :GM010  LDA     GXNEW-1,X       ; MOVE COORDINATES TO WORKING VARIABLES
A680  2A                  ROL     A               ; PREPARE TO ROUND.
A681  B5E3                LDA     GXNEW-3,X       ; GET MIDDLE BYTE.
A683  6900                ADC     #0              ; ADO MSB OF FRACTION.
A685  95BB                STA     GX1-3,X
A687  B5E4                LDA     GXNEW-2,X       ; GET MSB.
A689  6900                ADC     #0              ; CONTINUE ROUNDING.
A68B  95BC                STA     GX1-2,X
A68D  A900                LDA     #0              ; NOW CLEAR FRACTION.
A68F  95BD                STA     GX1-1,X
A691  CA                  DEX
A692  CA                  DEX
A693  CA                  DEX
A694  D0E8 ^A67E          BNE     :GM010

                  ; *S*   LDA     #0
A696  8DDB05              STA     NOPLOT

A699  ADD405              LDA     GROPR           ; GOTO?
A69C  C906                CMP     #GOTO
A69E  F018 ^A6B8          BEQ     :GM10F          ; YES.

A6A0  2071AB              JSR     NEWDEL          ; CALCULATE SLOPE DELTA3.
A6A3  5003 ^A6A8          BVC     :GM005
A6A5  4C78A7              JMP     :GM041          ; OVERFLOW.

A6A8  ADD405      :GM005  LDA     GROPR
A6AB  C90A                CMP     #DRAWTO         ; 'DRAWTO'?
A6AD  F035 ^A6E4          BEQ     :GM012          ; YES.

A6AF  2910                AND     #$10            ; 'FILL' OR 'FILLTO'?
A6B1  F008 ^A6BB          BEQ     :GM011          ; NO -- 'DRAW' OR 'GO'.

A6B3  AD1305              LDA     PEN             ; PEN ERASE ON FILL?
A6B6  D003 ^A6BB          BNE     :GM011          ; NO.

A6B8  4CCEA7      :GM10F  JMP     :GM150

A6BB  AD5E05      :GM011  LDA     EDGRUL          ; FREE?
A6BE  C908                CMP     #EFREE
A6C0  F00A ^A6CC          BEQ     :GM11F          ; YES -- CLIP.

A6C2  A244                LDX     #GX2-DTAB       ; IS START POINT IN BOUNDS?
A6C4  200DAB              JSR     INTEST
A6C7  D01B ^A6E4          BNE     :GM012          ; NO -- CLIP.

A6C9  4CB4A7              JMP     :GM120          ; YES -- HALT, WRAP OR BOUNCE.

                  ; CHECK FOR LINE SEGMENT WITHIN SCREEN LIMITS

                  ; THE CLIPPING ALGORITHM USED HERE IS DESCRIBED IN SECTION 5-1 OF THE
                  ; SECOND EDITION OF "PRINCIPLES OF INTERACTIVE COMPUTER GRAPHICS" BY
                  ; NEWMAN & SPROULL.

A6CC  ADD405      :GM11F  LDA     GROPR           ; "GO"?

A6CF  C905                CMP     #GO
A6D1  D011 ^A6E4          BNE     :GM012          ; NO.

A6D3  AD5E05              LDA     EDGRUL          ; EDGE RULE = FREE?
A6D6  C908                CMP     #EFREE
A6D8  D00A ^A6E4          BNE     :GM012          ; NO.

A6DA  A23E                LDX     #GX1-DTAB       ; END POINT IN BOUNDS?
A6DC  200DAB              JSR     INTEST
A6DF  F003 ^A6E4          BEQ     :GM012          ; YES.

A6E1  EEDB05              INC     NOPLOT          ; NO -- DON'T PLOT END POINT.

A6E4  A23E        :GM012  LDX     #GX1-DTAB       ; TEST END POINT.
A6E6  200DAB              JSR     INTEST
A6E9  8D4905              STA     GNUMB           ; SAVE RESULT.

A6EC  A244                LDX     #GX2-DTAB       ; TEST START POINT.
A6EE  200DAB              JSR     INTEST
A6F1  8D4A05              STA     GNUMB+1         ; SAVE RESULT.

A6F4  2D4905              AND     GNUMB
A6F7  F003 ^A6FC          BEQ     :GM013          ; PART OF LIME MAY BE IN SCREEN.

A6F9  4CE0A7      :GMOVF  JMP     :GM157          ; NO PART OF LINE IS IN SCREEN.

A6FC  AD4905      :GM013  LDA     GNUMB
A6FF  0D4A05              ORA     GNUMB+1
A702  D003 ^A707          BNE     :GM014          ; PART OF LINE IS OFF THE SCREEN.

A704  4CAFA7              JMP     :GM110          ; ALL OF LINE IS IN SCREEN.

A707  A23E        :GM014  LDX     #GX1-DTAB       ; FIND AN INTERSECTION WITH AN EDGE.
A709  AD4905              LDA     GNUMB           ; IS X1,Y1 OUTSIDE SCREEN?
A70C  D005 ^A713          BNE     :GM016          ; YES.

A70E  A244                LDX     #GX2-DTAB       ; NO -- THEN X2,Y2 MUST BE.
A710  AD4A05              LDA     GNUMB+1

A713  48          :GM016  PHA                     ; SAVE INTERSECT STATUS.
A714  2908                AND     #ELEFT          ; LEFT EDGE INTERSECTION?
A716  F00C ^A724          BEQ     :GM020          ; NO.

A718  38                  SEC                     ; YES -- 'GACC' = LEFT EDGE X VALUE.
A719  A900                LDA     #0              ; 'GACC' = -XC.
A71B  ED6105              SBC     XC
A71E  85CE                STA     GACC
A720  A9FF                LDA     #-1
A722  D00D ^A731          BNE     :GM025          ; (BRA).

A724  68          :GM020  PLA                     ; GET STATUS.
A725  48                  PHA
A726  2904                AND     #ERIGHT         ; RIGHT EDGE INTERSECTION?
A728  F036 ^A760          BEQ     :GM030          ; NO.

A72A  AD6105              LDA     XC              ; YES -- 'GACC' = RIGHT EDGE
A72D  85CE                STA     GACC            ; 'GACC' = XC.
A72F  A900                LDA     #0

A731  85CF        :GM025  STA     GACC+1          ; EXTEND SIGN.
A733  A04E                LDY     #GACC-DTAB      ; GX1 OR GX2 = 'GACC'.
A735  20459A              JSR     DMOVI

A738  8A                  TXA                     ; GY1 OR GY2 = (GACC-GX) * DELY / DELX + GY.
A739  48                  PHA
A73A  A24E                LDX     #GACC-DTAB
A73C  A06C                LDY     #GX-DTAB
A73E  2057AF              JSR     RSUBI

A741  A04C                LDY     #DELY-DTAB
A743  205BAE              JSR     QMULT

A746  A04A                LDY     #DELX-DTAB
A748  20BEAE              JSR     QDIV
A74B  D02B ^A778          BNE     :GM041          ; OVERFLOW -- DON'T DRAW.

A74D  A06F                LDY     #GY-DTAB
A74F  2050AF              JSR     RADDI

A752  68                  PLA
A753  AA                  TAX
A754  A5CE                LDA     GACC
A756  9583                STA     DTAB+3,X
A758  A5CF                LDA     GACC+1
A75A  9584                STA     DTAB+4,X
A75C  68                  PLA                     ; CLEAR STACK.
A75D  4CE4A6              JMP     :GM012          ; KEEP THIS UP UNTIL LINE SEGMENT IS CLIPPED.

A760  68          :GM030  PLA                     ; GET STATUS.
A761  48                  PHA
A762  2902                AND     #EBOTOM         ; BOTTOM EDGE INTERSECTION?
A764  F00C ^A772          BEQ     :GM040          ; NO.

A766  38                  SEC                     ; YES -- 'GACC' = BOTTOM EDGE Y VALUE.
A767  A900                LDA     #0              ; 'GACC' = -YC.
A769  ED6305              SBC     YC
A76C  85CE                STA     GACC
A76E  A9FF                LDA     #-1
A770  D010 ^A782          BNE     :GM045          ; (BRA).

A772              :GM040
A772  68                  PLA                     ; GET STATUS.
A773  48                  PHA
A774  2901                AND     #ETOP           ; TOP EDGE INTERSECTION?
A776  D003 ^A77B          BNE     :GM042          ; YES.

A778  4CE0A7      :GM041  JMP     :GM157

A77B              :GM042
A77B  AD6305              LDA     YC              ; 'GACC' = TOP EDGE Y VALUE.
A77E  85CE                STA     GACC            ; 'GACC' = YC.
A780  A900                LDA     #0

A782  85CF        :GM045  STA     GACC+1          ; EXTEND SIGN.

A784  9584                STA     DTAB+4,X        ; GY1 OR GY2 = 'GACC'
A786  A5CE                LDA     GACC
A788  9583                STA     DTAB+3,X

A78A  8A                  TXA                     ; SAVE X REGISTER.
A78B  48                  PHA                     ; GX1 OR GX2 = (GACC - GY) * DELX / DELY + GX.
A78C  A24E                LDX     #GACC-DTAB
A78E  A06F                LDY     #GY-DTAB
A790  2057AF              JSR     RSUBI

A793  A04A                LDY     #DELX-DTAB
A795  205BAE              JSR     QMULT

A798  A04C                LDY     #DELY-DTAB
A79A  20BEAE              JSR     QDIV
A79D  D0D9 ^A778          BNE     :GM041          ; OVERFLOW. -- DON'T DRAW.

A79F  A06C                LDY     #GX-DTAB
A7A1  2050AF              JSR     RADDI

A7A4  68                  PLA
A7A5  AA                  TAX
A7A6  A04E                LDY     #GACC-DTAB
A7A8  20459A              JSR     DMOVI
A7AB  68                  PLA                     ; CLEAR THE STACK.
A7AC  4CE4A6              JMP     :GM012          ; KEEP THIS UP UNTIL LINE SEGMENT IS CLIPPED.

A7AF  2071AB      :GM110  JSR     NEWDEL          ; CALCULATE SLOPE DELTAS FOR CLIPPED LINF
A7B2  70C4 ^A778          BVS     :GM041          ; OVERFLOW.

A7B4  201CA8      :GM120  JSR     NEWDRW          ; DRAW LINE.
A7B7  ADD505              LDA     HITWLL          ; HIT WALL?
A7BA  D00C ^A7C8          BNE     :GM130          ; YES.

A7BC  ADD405              LDA     GROPR
A7BF  C90A                CMP     #DRAWTO         ; 'DRAWTO'?
A7C1  F01D ^A7E0          BEQ     :GM157          ; YES

A7C3  ADD605              LDA     HITEDG          ; HIT EDGE?
A7C6  F018 ^A7E0          BEQ     :GM157          ; NO.

A7C8  20E9A7      :GM130  JSR     SETCR2          ; SET CURSOR COORDINATES.
A7CB  4CE3A7              JMP     :GM160          ; (BRA).

                  ; GOTO

A7CE  A23E        :GM150  LDX     #GX1-DTAB       ; CHECK FOR POINT IN SCREEN.
A7D0  200DAB              JSR     INTEST
A7D3  D00B ^A7E0          BNE     :GM157          ; NOT IN SCREEN -- DON'T PLOT.

A7D5  A03E                LDY     #GX1-DTAB
A7D7  20FFAB              JSR     SETCUR          ; CONVERT TO HANDLER COORDINATES.
A7DA  209FAA              JSR     CNVRT
A7DD  2093AA              JSR     PLOT            ; PLOT POINT IF PEN DOWN.

A7E0  208CAB      :GM157  JSR     NEWCUR          ; ESTABLISH NEW CURSOR POSITION.

A7E3  205BA5      :GM160  JSR     TRTPLC          ; PLACE VISIBLE TURTLE
A7E6  A4E0                LDY     LEND              ; RESTORE Y REGISTER
A7E8  60                  RTS

A7E9  38          SETCR2  SEC                     ; GX := GCOL-XC.
A7EA  ADCF05              LDA     GCOL            ; GXNEW := SAME.
A7ED  ED6105              SBC     XC
A7F0  85EC                STA     GX
A7F2  85E6                STA     GXNEW
A7F4  ADD005              LDA     GCOL+1
A7F7  ED6205              SBC     XC+1
A7FA  85ED                STA     GX+1
A7FC  85E7                STA     GXNEW+1

A7FE  38                  SEC                     ; GY := YC-GROW
A7FF  AD6305              LDA     YC              ; GYNEW := SAME.
A802  EDD105              SBC     GROW
A805  85EF                STA     GY
A807  85E9                STA     GYNEW
A809  A900                LDA     #0
A80B  E900                SBC     #0
A80D  85F0                STA     GY+1
A80F  85EA                STA     GYNEW+1

A811  A900                LDA     #0              ; CLEAR FRACTION.
A813  85EE                STA     GX+2
A815  85F1                STA     GY+2
A817  85E8                STA     GXNEW+2
A819  85EB                STA     GYNEW+2
A81B  60                  RTS


A81C                      PROC
                  ;
                  ; NEWDRW -- LINE DRAW ROUTINE
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       GX2,GY2 = START COORDINATE.
                  ;       GX1,GY1 = END COORDINATE.
                  ;       DELX,DELY DEFINES SLOPE OF LINE.
                  ;       PEN     = PIXEL VALUE.
                  ;       GSMODE  = SCREEN MODE.
                  ;       EDGRUL  = EDGE RULE IN EFFECT.
                  ;       GROPR   = OPERATION.
                  ;
                  ;       JSR     NEWDRW
                  ;
                  ;       HITWLL  = 0 IF NO WALL HIT
                  ;       HITEDG  = 0 IF NO EDGE HIT
                  ;       GCOL    = COL OF LAST DRAWN PIXEL
                  ;       GROW    = ROW OF LAST DRAWN PIXEL
                  ;
A81C  A044        NEWDRW  LDY     #GX2-DTAB     ; ROWCRS := YC - GY2.
A81E  20FFAB              JSR     SETCUR        ; COLCRS := GX2 + XC.
A821  209FAA              JSR     CNVRT
A824  A900                LDA     #0
A826  8DD705              STA     HALTFG
A829  8DD505              STA     HITWLL
A82C  8DD605              STA     HITEDG
A82F  ADD405              LDA     GROPR
A832  C905                CMP     #GO             ; 'GO'?
A834  F003 ^A839          BEQ     :DR020          ; YES -- DON'T PLOT START POINT.

A836  2093AA              JSR     PLOT            ; NO -- DRAW START POINT.

A839  A213        :DR020  LDX     #DELTAR-DTAB    ; DELTAR := ABS(DELY)
A83B  A04C                LDY     #DELY-DTAB
A83D  20459A              JSR     DMOVI
A840  20FF9C              JSR     DABSI

A843  A215                LDX     #DELTAC-DTAB    ; DELTAC := ABS(DELX)
A845  A04A                LDY     #DELX-DTAB
A847  20459A              JSR     DMOVI
A84A  20FF9C              JSR     DABSI

A84D  A213                LDX     #DELTAR-DTAB    ; IF DELTAR>DELTAC
A84F  A015                LDY     #DELTAC-DTAB
A851  20159C              JSR     DCMPI
A854  9028 ^A87E          BCC     :DR050

A856  A21E                LDX     #ENDPT-DTAB     ; THEN BEGIN.
A858  A013                LDY     #DELTAR-DTAB    ; ENDPT := DELTAR.
A85A  20459A              JSR     DMOVI
A85D  A21A                LDX     #COLAC-DTAB     ; COLAC := DELTAR/2.
A85F  20459A              JSR     DMOVI
A862  469B                LSR     COLAC+1
A864  669A                ROR     COLAC
A866  A900                LDA     #0              ; ROWAC := 0.

A868  8598                STA     ROWAC
A86A  8599                STA     ROWAC+1
A86C  A21C                LDX     #COUNTR-DTAB    ; COUNTR := ABS(GY1-GY2)
A86E  A041                LDY     #GY1-DTAB
A870  20459A              JSR     DMOVI
A873  A047                LDY     #GY2-DTAB
A875  20429C              JSR     DSUBI
A878  20FF9C              JSR     DABSI
A87B  4CA3A8              JMP     :DR060          ; END.

A87E  A21E        :DR050  LDX     #ENDPT-DTAB     ; ELSE BEGIN.
A880  A015                LDY     #DELTAC-DTAB    ; ENDPT := DELTAC.
A882  20459A              JSR     DMOVI
A885  A218                LDX     #ROWAC-DTAB     ; ROWAC := DELTAC/2.
A887  20459A              JSR     DMOVI
A88A  4699                LSR     ROWAC+1
A88C  6698                ROR     ROWAC
A88E  A900                LDA     #0              ; COLAC := 0.
A890  859A                STA     COLAC
A892  859B                STA     COLAC+1
A894  A21C                LDX     #COUNTR-DTAB    ; COUNTR := ABS(GX1-GX2).
A896  A03E                LDY     #GX1-DTAB
A898  20459A              JSR     DMOVI
A89B  A044                LDY     #GX2-DTAB
A89D  20429C              JSR     DSUBI
A8A0  20FF9C              JSR     DABSI           ; END.

A8A3  A59C        :DR060  LDA     COUNTR          ; IF COUNTR>0 THEN BEGIN.
A8A5  059D                ORA     COUNTR+1
A8A7  D003 ^A8AC          BNE     :DR60F
A8A9  4C30AA              JMP     :DR900

A8AC  A218        :DR60F  LDX     #ROWAC-DTAB     ; ROWAC := ROWAC + DELY.
A8AE  A04C                LDY     #DELY-DTAB
A8B0  20329C              JSR     DADDI
A8B3  A01E                LDY     #ENDPT-DTAB     ; IF ROWAC>=ENDPT THEN BEGIN.
A8B5  20229C              JSR     DSCMI
A8B8  9027 ^A8E1          BCC     :DR063

A8BA  20429C              JSR     DSUBI           ; ROWAC := ROWAC-ENDPT.
A8BD  C654                DEC     ROWCRS          ; ROWCRS := ROWCRS-1.
A8BF  A554                LDA     ROWCRS
A8C1  C9FF                CMP     #-1
A8C3  D065 ^A92A          BNE     :DR070

A8C5  8DD605              STA     HITEDG          ; SET EDGE HIT FLAG.
A8C8  AD5E05              LDA     EDGRUL          ; OFF TOP EDGE.
A8CB  C901                CMP     #EWRAP          ; WRAP?
A8CD  D007 ^A8D6          BNE     :DR061          ; NO -- MUST BE BOUNCE OR HALT.

A8CF  ADAB05              LDA     MAXROW          ; WRAP TO SCREEN BOTTOM EDGE.
A8D2  8554                STA     ROWCRS
A8D4  D054 ^A92A          BNE     :DR070          ; (BRA).

A8D6  E654        :DR061  INC     ROWCRS          ; BRING TURTLE BACK IN.
A8D8  C902                CMP     #EHALT          ; HALT?
A8DA  D030 ^A90C          BNE     :DR067          ; NO.

A8DC  8DD705              STA     HALTFG          ; YES -- SET FLAG.
A8DF  F049 ^A92A          BEQ     :DR070          ; (BRA).

A8E1  A599        :DR063  LDA     ROWAC+1         ; ELSE IF ROW AC < 0 THEN BEGIN.
A8E3  1045 ^A92A          BPL     :DR070

A8E5  20329C              JSR     DADDI           ; ROWAC := ROWAC + ENDPT.
A8E8  E654                INC     ROWCRS          ; ROWCRS := ROWCRS+1; END.

A8EA  ADAB05              LDA     MAXROW
A8ED  C554                CMP     ROWCRS
A8EF  B039 ^A92A          BCS     :DR070          ; ROWCRS <= MAXROW.

A8F1  8DD605              STA     HITEDG          ; SET EDGE HIT FLAG.
A8F4  AD5E05              LDA     EDGRUL          ; OFF BOTTOM EDGE.
A8F7  C901                CMP     #EWRAP          ; WRAP?
A8F9  D006 ^A901          BNE     :DR065          ; NO -- MUST BE BOUNCE OR HALT.

A8FB  A900                LDA     #0              ; WRAP TO SCREEN TOP EDGE.
A8FD  8554                STA     ROWCRS
A8FF  F029 ^A92A          BEQ     :DR070          ; (BRA).

A901  C654        :DR065  DEC     ROWCRS          ; BRING TURTLE BACK IN.
A903  C902                CMP     #EHALT          ; HALT?
A905  D005 ^A90C          BNE     :DR067          ; NO.

A907  8DD705              STA     HALTFG          ; YES -- SET FLAG.
A90A  F01E ^A92A          BEQ     :DR070          ; (BRA).

A90C  20F19C      :DR067  JSR     DNEGI           ; ROWAC:= ENDPT-ROWAC-1.
A90F  20329C              JSR     DADDI
A912  20129D              JSR     DDCRI

A915  38                  SEC                     ; THETA := THETA-180.
A916  A9B4                LDA     # LOW 180
A918  E5F2                SBC     THETA
A91A  85F2                STA     THETA
A91C  A900                LDA     # HIGH 180
A91E  E5F3                SBC     THETA+1
A920  85F3                STA     THETA+1
A922  2096AB              JSR     MOD360

A925  A24C                LDX     #DELY-DTAB      ; DELY != -DELY.
A927  20F19C              JSR     DNEGI

A92A  A21A        :DR070  LDX     #COLAC-DTAB     ; COLAC := COLAC+DELX.
A92C  A04A                LDY     #DELX-DTAB
A92E  20329C              JSR     DADDI
A931  A01E                LDY     #ENDPT-DTAB     ; IF COLAC >= ENOPT THEN BEGIN.
A933  20229C              JSR     DSCMI
A936  9035 ^A96D          BCC     :DR073

A938  20429C              JSR     DSUBI           ; COLAC := COLAC-ENDPT.
A93B  2043B2              JSR     INCCOL          ; COLCRS := COLCRS+1.
A93E  ADAD05              LDA     MAXCOL+1
A941  C556                CMP     COLCRS+1
A943  D005 ^A94A          BNE     :DR70F

A945  ADAC05              LDA     MAXCOL
A948  C555                CMP     COLCRS
A94A  B06B ^A9B7  :DR70F  BCS     :DR080          ; COLCRS <= MAXCOL.

A94C  8DD605              STA     HITEDG          ; SET EDGE HIT FLAG.
A94F  AD5E05              LDA     EDGRUL          ; OFF RIGHT EDGE.
A952  C901                CMP     #EWRAP          ; WRAP?
A954  D008 ^A95E          BNE     :DR071          ; NO -- MUST BE BOUNCE OR HALT.

A956  A900                LDA     #0              ; WRAP SCREEN LEFT EDGE.
A958  8555                STA     COLCRS
A95A  8556                STA     COLCRS+1
A95C  F059 ^A9B7          BEQ     :DR080          ; (BRA).

A95E  204AB2      :DR071  JSR     DECCOL          ; BRING TURTLE BACK IN.
A961  AD5E05              LDA     EDGRUL
A964  C902                CMP     #EHALT          ; HALT?
A966  D039 ^A9A1          BNE     :DR077          ; NO.

A968  8DD705              STA     HALTFG          ; YES -- SET FLAG.
A96B  F04A ^A9B7          BEQ     :DR080          ; (BRA).

A96D  A59B        :DR073  LDA     COLAC+1         ; ELSE IF COLAC < 0 THEN BEGIN.
A96F  1046 ^A9B7          BPL     :DR080

A971  20329C              JSR     DADDI           ; COLAC := COLAC+ENDPT.
A974  204AB2              JSR     DECCOL          ; COLCRS := COLCRS-1.

A977  A556                LDA     COLCRS+1
A979  103C ^A9B7          BPL     :DR080          ; COLORS >= MINCOL.

A97B  8DD605              STA     HITEDG          ; SET EDGE HIT FLAG.
A97E  AD5E05              LDA     EDGRUL          ; OFF LEFT EDGE.
A981  C901                CMP     #EWRAP          ; WRAP?
A983  D00D ^A992          BNE     :DR075          ; NO -- MUST BE BOUNCE.

A985  ADAC05              LDA     MAXCOL          ; WRAP TO SCREEN RIGHT EDGE.
A988  8555                STA     COLCRS
A98A  ADAD05              LDA     MAXCOL+1
A98D  8556                STA     COLCRS+1
A98F  4CB7A9              JMP     :DR080

A992  2043B2      :DR075  JSR     INCCOL          ; BRING TURTLE BACK IN.
A995  AD5E05              LDA     EDGRUL
A998  C902                CMP     #EHALT          ; HALT?
A99A  D005 ^A9A1          BNE     :DR077          ; NO

A99C  8DD705              STA     HALTFG          ; YES -- SET FLAG.
A99F  F016 ^A9B7          BEQ     :DR080          ; (BRA).

A9A1  20F19C      :DR077  JSR     DNEGI           ; COLAC:=ENDPT-COLAC-1.
A9A4  20329C              JSR     DADDI
A9A7  20129D              JSR     DDCRI

A9AA  A272                LDX     #THETA-DTAB     ; THETA := -THETA.
A9AC  20F19C              JSR     DNEGI
A9AF  2096AB              JSR     MOD360
A9B2  A24A                LDX     #DELX-DTAB      ; DELX := -DELX.
A9B4  20F19C              JSR     DNEGI


A9B7  ADD705      :DR080  LDA     HALTFG          ; HALT?
A9BA  F005 ^A9C1          BEQ     :DR081          ; NO.

A9BC  8DD605              STA     HITEDG          ; YES -- SET EDGE HIT FLAG.
A9BF  D06F ^AA30          BNE     :DR900          ; STOP DRAWING (BRA).


A9C1  ADCD05      :DR081  LDA     WALLS           ; WALLS ACTIVE?
A9C4  0DCE05              ORA     WALLS+1
A9C7  F00D ^A9D6          BEQ     :DR082          ; NO.

A9C9  2067AA              JSR     SGSTUF          ; SAVE GROW & GCOL.
A9CC  207CB2              JSR     TSTPIX          ; GET PIXEL VALUE AT CURRENT POSITIGN
A9CF  202BAC              JSR     WALLCK          ; IS IT A WALL?
A9D2  D056 ^AA2A          BNE     :DR300          ; YES -- BACKUP TO PRIOR POSITION.

A9D4  F003 ^A9D9          BEQ     :DR084          ; (BRA)

A9D6  209FAA      :DR082  JSR     CNVRT           ; ROW/COLUMN TO MEM ADDRESS.

A9D9  ADD405      :DR084  LDA     GROPR           ; 'GO'.
A9DC  C905                CMP     #GO
A9DE  F03F ^AA1F          BEQ     :DR085          ; YES -- DON'T PLOT INTERMEDIATE POINT.

A9E0  2093AA              JSR     PLOT            ; PLOT POINT IF PEN DOWN.

A9E3  ADD405              LDA     GROPR           ; 'FILL' OR 'FILLTO'?
A9E6  2910                AND     #$10
A9E8  F035 ^AA1F          BEQ     :DR085          ; NO.

A9EA  A900                LDA     #0              ; YES -- SETUP FOR TSTPIX CALL.
A9EC  8D9C05              STA     FLDCLR
A9EF  A555                LDA     COLCRS          ; SAVE CURRENT CURSOR POSITION.
A9F1  48                  PHA
A9F2  A556                LDA     COLCRS+1
A9F4  48                  PHA

A9F5  2093B2      :DR84D  JSR     TSTCOL          ; SEE IF TURTLE AT RIGHT EDGE.
A9F8  AD9F05              LDA     COLFLG
A9FB  2940                AND     #$40
A9FD  D006 ^AA05          BNE     :DR84E          ; YES

A9FF  2043B2              JSR     INCCOL          ; NO.
AA02  4C0BAA              JMP     :DR84F

AA05  A900        :DR84E  LDA     #0              ; SET TURTLE TO LEFT EDGE.
AA07  8555                STA     COLCRS
AA09  8556                STA     COLCRS+1

AA0B  207CB2      :DR84F  JSR     TSTPIX          ; IS TURTLE OVER BACKGROUND?
AA0E  D006 ^AA16          BNE     :DR84M          ; NO -- ALL DONE WITH SCAN.

AA10  2093AA              JSR     PLOT            ; YES -- REPLACE WITH FILL COLOR.
AA13  4CF5A9              JMP     :DR84D

AA16  68          :DR84M  PLA
AA17  8556                STA     COLCRS+1
AA19  68                  PLA
AA1A  8555                STA     COLCRS
AA1C  209FAA              JSR     CNVRT           ; REESTABLISH VISIBLE TURTLE.

AA1F  A21C        :DR085  LDX     #COUNTR-DTAB    ; COUNTR := COUNTR-1.
AA21  20129D              JSR     DDCRI
AA24  2048AA              JSR     SPDDEL
AA27  4CA3A8              JMP     :DR060          ; END.

AA2A  8DD505      :DR300  STA     HITWLL          ; SET FLAG.
AA2D  207AAA              JSR     RGSTUF          ; RESTORE GROW & GCOL.

AA30  ADD405      :DR900  LDA     GROPR           ; GO?
AA33  C905                CMP     #GO
AA35  D010 ^AA47          BNE     :DR990          ; NO.

AA37  ADD505              LDA     HITWLL          ; WALL HIT?
AA3A  D00B ^AA47          BNE     :DR990          ; YES -- DON'T PLOT POINT.

AA3C  ADDB05              LDA     NOPLOT          ; PLOT INHIBIT.
AA3F  D006 ^AA47          BNE     :DR990          ; YES -- DON'T PLOT POINT.

AA41  209FAA              JSR     CNVRT           ; PLOT STOP POINT.
AA44  2093AA              JSR     PLOT
AA47  60          :DR990  RTS

AA48                      PROC

AA48  AE5D05      SPDDEL  LDX     SPEED           ; CHECK SPEED SELECTION.
AA4B  F00E ^AA5B          BEQ     :SD200          ; FULL SPEED AHEAD.

AA4D  A514        :SD100  LDA     RTCLOK+2        ; COUNT CLOCK TICKS.

AA4F  C514        :SD110  CMP     RTCLOK+2        ; WAIT FOR ONE TICK.
AA51  F0FC ^AA4F          BEQ     :SD110

AA53  2022AC              JSR     GABRTC          ; OPERATOR BREAK?
AA56  F004 ^AA5C          BEQ     :SD300          ; YES.

AA58  CA                  DEX                     ; DONE?
AA59  D0F2 ^AA4D          BNE     :SD100          ; NO.

AA5B  60          :SD200  RTS

AA5C  20E9A7      :SD300  JSR     SETCR2          ; SET CURSOR.
AA5F  205BA5              JSR     TRTPLC          ; PLACE TURTLE.
AA62  A987                LDA     #ABTERR
AA64  4C3A7A              JMP     PSTOP

AA67  ADD105      SGSTUF  LDA     GROW            ; YES SAVE PRIOR POSITION.
AA6A  8DA005              STA     SAVROW
AA6D  ADCF05              LDA     GCOL
AA70  8DA105              STA     SAVCOL
AA73  ADD005              LDA     GCOL+1
AA76  8DA205              STA     SAVCOL+1
AA79  60                  RTS

AA7A  ADA005      RGSTUF  LDA     SAVROW          ; RESTORE PRIOR POSITION.
AA7D  8DD105              STA     GROW
AA80  EED905              INC     TUFLAG
AA83  ADA105              LDA     SAVCOL
AA86  8DCF05              STA     GCOL
AA89  ADA205              LDA     SAVCOL+1
AA8C  8DD005              STA     GCOL+1
AA8F  CED905              DEC     TUFLAG
AA92  60                  RTS

AA93  AD1305      PLOT    LDA     PEN             ; PEN UP?
AA96  3006 ^AA9E          BMI     :PL090          ; YES -- DON'T PLOT POINT.

AA98  8D9B05              STA     FCOLOR
AA9B  2056B2              JSR     FPLOT

AA9E  60          :PL090  RTS


AA9F                      PROC
                  ;
                  ; CONVERT ROW/COLUMN CURSOR INTO REAL ADDRESS (FROM SAVMSC ON UP).
                  ;
AA9F  A201        CNVRT   LDX     #01
AAA1  8EAE05              STX     MLTTMP          ; VERTICAL CALCULATIONS.
AAA4  CA                  DEX                     ; VERTICAL CALCULATIONS.
AAA5  86F7                STX     ADRESS+1        ; CLEAR HI BYTE.
AAA7  A554                LDA     ROWCRS          ; ADRESS := ROWCRS*5.
AAA9  8DD105              STA     GROW            ; FOR VISIBLE TURTLE.
AAAC  0A                  ASL     A               ; MULTIPLY BY 4.
AAAD  26F7                ROL     ADRESS+1
AAAF  0A                  ASL     A
AAB0  26F7                ROL     ADRESS+1        ; CLEAR CARRY.
AAB2  6554                ADC     ROWCRS          ; ADD TO MAKE *5.
AAB4  85F6                STA     ADRESS
AAB6  9002 ^AABA          BCC     :CNVR0
AAB8  E6F7                INC     ADRESS+1
AABA  AC3705      :CNVR0  LDY     GSMODE          ; GET MODE
AABD  BEBCB8              LDX     DHLINE,Y        ; GET NUMBER OF SHIFTS.

AAC0  06F6        :CNVR1  ASL     ADRESS          ; ADRESS := ADRESS *X.
AAC2  26F7                ROL     ADRESS+1        ; DO THE DIVIDE.
AAC4  CA                  DEX
AAC5  D0F9 ^AAC0          BNE     :CNVR1

AAC7  A556                LDA     COLCRS+1        ; HORIZONTAL CALCULATIONS.
AAC9  EED905              INC     TUFLAG          ; SET INTERLOCK FOR GCOL UPDATE
AACC  8DD005              STA     GCOL+1          ; FOR VISIBLE TURTLE.
AACF  4A                  LSR     A               ; SAVE LS8 FOR LATER.
AAD0  A555                LDA     COLCRS          ; GET LOW BYTE.

AAD2  8DCF05              STA     GCOL            ; FOR VISIBLE TURTLE.
AAD5  CED905              DEC     TUFLAG          ; CLEAR INTERLOCK.
AAD8  BE30B3              LDX     DIV2TB,Y        ; GET SHIFT AMOUNT.
AADB  F007 ^AAE4          BEQ     :CNVR3          ; CARRY CLEAR IF NO SHIFT.

AADD  6A          :CNVR2  ROR     A               ;  ROLL IN THE CARRY.
AADE  0EAE05              ASL     MLTTMP          ; SHIFT INDEX.
AAE1  CA                  DEX
AAE2  D0F9 ^AADD          BNE     :CNVR2

AAE4  65F6        :CNVR3  ADC     ADRESS          ; CARRY IS ALWAYS CLEAR.
AAE6  9002 ^AAEA          BCC     :CNVR4
AAE8  E6F7                INC     ADRESS+1
AAEA  18          :CNVR4  CLC
AAEB  6558                ADC     SAVMSC
AAED  85F6                STA     ADRESS
AAEF  A5F7                LDA     ADRESS+1
AAF1  6559                ADC     SAVMSC+1
AAF3  85F7                STA     ADRESS+1
AAF5  BE30B3              LDX     DIV2TB,Y
AAF8  BDCCB8              LDA     HMASK,X
AAFB  2555                AND     COLCRS
AAFD  6DAE05              ADC     MLTTMP
AB00  A8                  TAY                     ; MAKE A NEW INDEX.
AB01  B940B3              LDA     DMASKT,Y        ; GET THE FINAL MASK.
AB04  8DB105              STA     DMASK
AB07  8DB005              STA     SHFAMT
AB0A  A000                LDY     #00
AB0C  60                  RTS


AB0D                      PROC
                  ;
                  ; INTEST -- TEST FOR POINT WITHIN SCREEN LIMITS.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = DTAB OFFSET TO X,Y PAIR (EACH TRIPLE PRECISION)
                  ;
                  ;       JSR     INTEST
                  ;       BEQ     POINT IN SCREEN
                  ;
                  ;       A = EDGE TEST BITS (0000LRBT), WHERE 1=OUT OF BOUNDS FOR THAT EDGE.

AB0D  84A9        INTEST  STY     TEMP2+2         ; SAVE Y REGISTER.
AB0F  A027                LDY     #TEMP2-DTAB
AB11  A900                LDA     #0              ; INITIALIZE RESULT BYTE.
AB13  48                  PHA
AB14  85A8                STA     TEMP2+1
AB16  B581                LDA     DTAB+1,X        ; CHECK SIGN OF POSITION.
AB18  3011 ^AB2B          BMI     :IT010          ; NEGATIVE -- COULDN'T BE BEYOND RIGHT EDGE.

AB1A  AD6105              LDA     XC              ; SETUP RIGHT EDGE X POSITION
AB1D  85A7                STA     TEMP2
AB1F  20229C              JSR     DSCMI           ; TEST RIGHT EDGE.
AB22  901A ^AB3E          BCC     :IT020          ; INSIDE SCREEN.
AB24  F018 ^AB3E          BEQ     :IT020

AB26  68                  PLA                     ; OUTSIDE -- SET STATUS BIT.
AB27  0904                ORA     #ERIGHT
AB29  D012 ^AB3D          BNE     :IT019          ; (BRA).

AB2B  38          :IT010  SEC                     ; SET UP LEFT EDGE POSITION.
AB2C  A900                LDA     #0
AB2E  ED6105              SBC     XC
AB31  85A7                STA     TEMP2
AB33  C6A8                DEC     TEMP2+1
AB35  20229C              JSR     DSCMI           ; TEST LEFT EDGE.
AB38  B004 ^AB3E          BCS     :IT020          ; INSIDE.

AB3A  68                  PLA                     ; OUTSIDE -- SFT STATUS BIT.
AB3B  0908                ORA     #ELEFT

AB3D  48          :IT019  PHA

AB3E  E8          :IT020  INX                     ; ADVANCE TO Y POSITION.
AB3F  E8                  INX
AB40  E8                  INX
AB41  A900                LDA     #0
AB43  85A8                STA     TEMP2+1
AB45  B581                LDA     DTAB+1,X        ; CHECK SIGN OF POSITION.
AB47  1014 ^AB5D          BPL     :IT030          ; POSITIVE -- COULDN'T BE BELOW BOTTOM EDGE.

AB49  38                  SEC                     ; SET UP BOTTOM EDGE POSITION.
AB4A  A900                LDA     #0
AB4C  ED6305              SBC     YC
AB4F  85A7                STA     TEMP2
AB51  C6A8                DEC     TEMP2+1
AB53  20229C              JSR     DSCMI           ; TEST BOTTOM EDGE.
AB56  B015 ^AB6D          BCS     :IT040          ; INSIDE.

AB58  68                  PLA                     ; OUTSIDE -- SET STATUS BIT.
AB59  0902                ORA     #EBOTOM
AB5B  D00F ^AB6C          BNE     :IT039          ; (BRA).

AB5D  AD6305      :IT030  LDA     YC              ; SETUP TOP EDGE POSITION.
AB60  85A7                STA     TEMP2
AB62  20229C              JSR     DSCMI           ; TEST TOP EDGE.
AB65  9006 ^AB6D          BCC     :IT040          ; INSIDE.
AB67  F004 ^AB6D          BEQ     :IT040

AB69  68                  PLA                     ; OUTSIDE -- SET STATUS BIT.
AB6A  0901                ORA     #ETOP

AB6C  48          :IT039  PHA

AB6D  A4A9        :IT040  LDY     TEMP2+2         ; RESTORE Y REGISTER.
AB6F  68                  PLA                     ; GET STATUS BYTE FOR EXIT.
AB70  60                  RTS


AB71                      PROC
                  ;
                  ; NEWDEL -- COMPUTE SLOPE DELTAS.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       JSR     NEWDEL
                  ;       BVS     OVERFLOW
                  ;
                  ;       DELX := GX1-GX2.
                  ;       DELY := GY1-GY2.
                  ;
AB71  A24A        NEWDEL  LDX     #DELX-DTAB      ; DELX := GX1-GX2.
AB73  A03E                LDY     #GX1-DTAB
AB75  20459A              JSR     DMOVI
AB78  A044                LDY     #GX2-DTAB
AB7A  20429C              JSR     DSUBI
AB7D  700C ^AB8B          BVS     :ND092

AB7F  A24C                LDX     #DELY-DTAB      ; DELY := GY1-GY2.
AB81  A041                LDY     #GY1-DTAB
AB83  20459A              JSR     DMOVI
AB86  A047                LDY     #GY2-DTAB
AB88  20429C              JSR     DSUBI

AB8B  60          :ND092  RTS


AB8C                      PROC
                  ;
                  ; NEWCUR -- MOVE NEW CURSOR TO CURRENT CURSOR.
                  ;
                  ;       'GX'    := 'GXNEW'
                  ;       'GY'    := 'GYNEW'
                  ;
AB8C  A206        NEWCUR  LDX     #6              ; 2 VARIABLES OF 3 BYTES EACH.

AB8E  B5E5        :NC010  LDA     GXNEW-1,X
AB90  95EB                STA     GX-1,X
AB92  CA                  DEX
AB93  D0F9 ^AB8E          BNE     :NC010

AB95  60                  RTS

AB96                      PROC
                  ;
                  ; MOD36 -- 'THETA' = 'THETA ' MODULO 360
                  ;
AB96  A5F3        MOD360  LDA     THETA+1         ; SEE IF ANGLE IS NEGATIVE.
AB98  1022 ^ABBC          BPL     :MD020          ; NO.

AB9A  A272                LDX     #THETA-DTAB     ; YES.
AB9C  20F19C              JSR     DNEGI           ; GET ABSOLUTE VALUE.
AB9F  A5F3                LDA     THETA+1         ; THETA = 32768 IS A SPECIAL CASE.
ABA1  3043 ^ABE6          BMI     :MD030

ABA3  2096AB              JSR     MOD360          ; *** RECURSIVE CALL ***

ABA6  A5F2                LDA     THETA           ; TEST FOR RESULT = 0.
ABA8  05F3                ORA     THETA+1
ABAA  F052 ^ABFE          BEQ     :MD099          ; YES -- DONE.

ABAC  A968                LDA     # LOW 360       ; NO -- THETA = 360 - MOD(ABS(THETA)).
ABAE  38                  SEC
ABAF  E5F2                SBC     THETA
ABB1  85F2                STA     THETA
ABB3  A901                LDA     # HIGH 360
ABB5  E5F3                SBC     THETA+1
ABB7  85F3                STA     THETA+1
ABB9  4CEEAB              JMP     :MD090

ABBC  A5F3        :MD020  LDA     THETA+1         ; COMPARE WITH 360.
ABBE  C901                CMP     # HIGH 360
ABC0  D004 ^ABC6          BNE     :MD025

ABC2  A5F2                LDA     THETA
ABC4  C968                CMP     # LOW 360
ABC6  9026 ^ABEE  :MD025  BCC     :MD090          ; THETA < 360.

ABC8  A968                LDA     # LOW 360       ; PREPARE TO DIVIDE BY 360.
ABCA  85A7                STA     TEMP2
ABCC  A901                LDA     # HIGH 360
ABCE  85A8                STA     TEMP2+1

ABD0  84A9                STY     TEMP2+2
ABD2  A272                LDX     #THETA-DTAB
ABD4  A027                LDY     #TEMP2-DTAB
ABD6  20879C              JSR     DDIVI
ABD9  A4A9                LDY     TEMP2+2

ABDB  A5A1                LDA     TEMP            ; REMAINDER IN 'TEMP' AFTER DIVIDE.
ABDD  85F2                STA     THETA
ABDF  A5A2                LDA     TEMP+1
ABE1  85F3                STA     THETA+1
ABE3  4CEEAB              JMP     :MD090


ABE6  A960        :MD030  LDA     # LOW 352       ; -32769 MOD 360 = 352
ABE8  85F2                STA     THETA
ABEA  A901                LDA     # HIGH 352
ABEC  85F3                STA     THETA+1

ABEE  EED905      :MD090  INC     TUFLAG          ; INTERLOCK FOR GANGLE UPDATE.
ABF1  A5F2                LDA     THETA
ABF3  8DD205              STA     GANGLE
ABF6  A5F3                LDA     THETA+1
ABF8  8DD305              STA     GANGLE+1
ABFB  CED905              DEC     TUFLAG          ; CLEAR INTERLOCK.

ABFE  60          :MD099  RTS

ABFF                      PROC
                  ;
                  ; SETCUR -- SET HANDLER CURSOR
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       Y = DTAB OFFSET TO TRIPLE PRECISION X,Y POSITION.
                  ;
                  ;       JSR     SETCUR
                  ;
ABFF  B98200      SETCUR  LDA     DTAB+2,Y
AC02  2A                  ROL     A
AC03  B98000              LDA     DTAB,Y
AC06  6D6105              ADC     XC
AC09  8555                STA     COLCRS
AC0B  B98100              LDA     DTAB+1,Y
AC0E  6D6205              ADC     XC+1
AC11  8556                STA     COLCRS+1

AC13  B98500              LDA     DTAB+5,Y
AC16  4980                EOR     #SB
AC18  2A                  ROL     A
AC19  AD6305              LDA     YC
AC1C  F98300              SBC     DTAB+3,Y
AC1F  8554                STA     ROWCRS

AC21  60                  RTS


AC22                      PROC
                  ;
                  ; GABRTC -- GRAPHICS GPERATOR ABORT CHECKER
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       JSR     GABRTC
                  ;       BEQ     ABORT
                  ;
AC22  A511        GABRTC  LDA     BREAK           ; OPERATOR ABORT?
AC24  D004 ^AC2A          BNE     :GA090          ; NO.

AC26  C611                DEC     BREAK           ; YES -- RESET FLAG.
AC28  A900                LDA     #0              ; SET EXIT STATUS.
AC2A  60          :GA090  RTS

AC2B                      PROC
                  ;
                  ; WALLCK -- CHECKS TO SEE IF PIXEL VALUE IS A WALL.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       A =     PIXEL VALUE (00-$0F)
                  ;
                  ;       JSR     WALLCK
                  ;       BNE     PIXEL IS A WALL
                  ;

AC2B  0A          WALLCK  ASL     A               ; X2.
AC2C  AA                  TAX
AC2D  F00E ^AC3D          BEQ     :WL090          ; BACKGROUND CAN'T BE A WALL.

AC2F  BD3EAC              LDA     WMASK,X
AC32  2DCD05              AND     WALLS
AC35  D006 ^AC3D          BNE     :WL090          ; FOUND US A WALL.

AC37  BD3FAC              LDA     WMASK+1,X
AC3A  2DCE05              AND     WALLS+1

AC3D  60          :WL090  RTS                     ; RETURN WITH CC SET.


AC3E  0000010002  WMASK   DW 0,$01,$02,$04,$08,$10,$20,$40,$80
AC50  0001000200          DW $100,$200,$400,$800,$1000,$2000,$4000


AC5E                      PROC
                  ;
                  ; GREAD -- READ GRAPHICS DATA FROM SCREEN.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       CURSOR ALREADY SET TO LOCATION TO READ.
                  ;
                  ;       JSR     GREAD
                  ;
                  ;       A = VALUE OF PIXEL AT CURSOR LOCATION.
                  ;       C = 0 IF TURTLE ON SCREEN, 1 IF OFF.
                  ;
AC5E  A592        GREAD   LDA     EXEC            ; EXECUTE MODE?
AC60  F032 ^AC94          BEQ     :GR090          ; NO.

AC62  AD1405              LDA     GRFLAG          ; YES -- GRAPHICS SCREEN?
AC65  F02D ^AC94          BEQ     :GR090          ; NO.

AC67  A206                LDX     #6

AC69  B5EB        :GR010  LDA     GX-1,X          ; ROUND GX TO GX1 ...
AC6B  2A                  ROL     A               ; ... & GY TO GY1.
AC6C  B5E9                LDA     GX-3,X
AC6E  6900                ADC     #0
AC70  95BB                STA     GX1-3,X
AC72  B5EA                LDA     GX-2,X
AC74  6900                ADC     #0
AC76  95BC                STA     GX1-2,X
AC78  CA                  DEX
AC79  CA                  DEX
AC7A  CA                  DEX
AC7B  D0EC ^AC69          BNE     :GR010

AC7D  A23E                LDX     #GX1-DTAB       ; YES -- CHECK FOR POINT IN SCREEN LIMITS.
AC7F  200DAB              JSR     INTEST
AC82  D010 ^AC94          BNE     :GR090          ; NOT IN LIMITS -- RETURN VALUE OF ZERO.

AC84  8CD805              STY     GRTEMP          ; SAVE Y REGISTER.
AC87  A03E                LDY     #GX1-DTAB       ; SET CURSOR POSITION.
AC89  20FFAB              JSR     SETCUR

AC8C  207CB2              JSR     TSTPIX          ; GET PIXEL VALUE.
AC8F  ACD805              LDY     GRTEMP
AC92  18                  CLC
AC93  60                  RTS

AC94  A900        :GR090  LDA     #0              ; RETURN VALUE OF ZERO.
AC96  38                  SEC
AC97  60          VTSRET  RTS

AC98                      PROC
AC98  A900        VTSENS  LDA     #0              ; ASSUME NO OBSTACLE INITIALLY.
AC9A  8D5005              STA     TRTSNS
AC9D  AD1405              LDA     GRFLAG          ; GRAPHICS MODE?
ACA0  F0F5 ^AC97          BEQ     VTSRET          ; NO --* ALL DONE?

ACA2  2067AA              JSR     SGSTUF          ; SAVE GCOL & GROW.
ACA5  98                  TYA                     ; SAVE. Y REGISTER.
ACA6  48                  PHA
ACA7  AD1305              LDA     PEN             ; SAVE PEN.
ACAA  48                  PHA
ACAB  AD5E05              LDA     EDGRUL          ; SAVE EDGE RULE.
ACAE  48                  PHA
ACAF  A206                LDX     #6              ; SAVE TURTLE LOCATION.

ACB1  B5EB        :ST010  LDA     GX-1,X
ACB3  48                  PHA
ACB4  CA                  DEX
ACB5  D0FA ^ACB1          BNE     :ST010

ACB7  ADCD05              LDA     WALLS           ; SAVE WALL SELECTIONS.
ACBA  48                  PHA
ACBB  ADCE05              LDA     WALLS+1
ACBE  48                  PHA

ACBF  AE4E05              LDX     ESTKP           ; ANYTHING IN EXPSTK?
ACC2  F006 ^ACCA          BEQ     :ST017          ; NO.

ACC4  B592        :ST015  LDA     EXPSTK-1,X      ; YES -- SAVE IT ALL.
ACC6  48                  PHA
ACC7  CA                  DEX
ACC8  D0FA ^ACC4          BNE     :ST015

ACCA  A900        :ST017  LDA     #0              ; CLEAR WALLS.
ACCC  8DCD05              STA     WALLS
ACCF  8DCE05              STA     WALLS+1
ACD2  A980                LDA     #PCUP           ; SET PEN TO UP.
ACD4  8D1305              STA     PEN
ACD7  AD5E05              LDA     EDGRUL          ; IF EDGE RULE = HALT, CHANGE TO FREE.
ACDA  C902                CMP     #EHALT
ACDC  D005 ^ACE3          BNE     :ST020

ACDE  A908                LDA     #EFREE
ACE0  8D5E05              STA     EDGRUL

ACE3  A905        :ST020  LDA     #GO             ; SIMULATE A GO 1.
ACE5  8DD405              STA     GROPR
ACE8  A900                LDA     #0
ACEA  8594                STA     EXPSTK+1
ACEC  A901                LDA     #1
ACEE  8593                STA     EXPSTK
ACF0  2032A2              JSR     CALDEL
ACF3  207AA6              JSR     GMOVE

ACF6  AE4E05              LDX     ESTKP           ; RESTORE EXPSTK?
ACF9  F00B ^AD06          BEQ     :ST023          ; NO.

ACFB  A200                LDX     #0

ACFD  68          :ST022  PLA
ACFE  9593                STA     EXPSTK,X
AD00  E8                  INX
AD01  EC4E05              CPX     ESTKP
AD04  D0F7 ^ACFD          BNE     :ST022

AD06  68          :ST023  PLA
AD07  8DCE05              STA     WALLS+1
AD0A  68                  PLA
AD0B  8DCD05              STA     WALLS
AD0E  205EAC              JSR     GREAD
AD11  B008 ^AD1B          BCS     :ST025          ; NOT IN SCREEN.

AD13  202BAC              JSR     WALLCK          ; WALL?
AD16  F009 ^AD21          BEQ     :ST030          ; NO

AD18  CE5005              DEC     TRTSNS
AD1B  EE5005      :ST025  INC     TRTSNS          ; YES -- SET SENSOR.
AD1E  EE5005              INC     TRTSNS
AD21  A200        :ST030  LDX     #0              ; RESTORE TURTLE POSITION

AD23  68          :ST040  PLA
AD24  95EC                STA     GX,X
AD26  95E6                STA     GXNEW,X
AD28  E8                  INX
AD29  E006                CPX     #6
AD2B  D0F6 ^AD23          BNE     :ST040

AD2D  68                  PLA                     ; RESTORE EDGE RULE.
AD2E  8D5E05              STA     EDGRUL
AD31  68                  PLA                     ; RESTORE PEN.
AD32  8D1305              STA     PEN
AD35  207AAA              JSR     RGSTUF          ; RESTORE GCOL & GROW.
AD38  68                  PLA
AD39  A8                  TAY                     ; RESTORE Y-REGISTFR.
AD3A  60                  RTS

AD3B                      PROC
                  ;
                  ; SINVAL -- GET VALUE OF SIN(THETA+A*90)
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       A = QUADRANT OFFSET (0-3)
                  ;       'THETA' = ANGLE (0-359)
                  ;
                  ;       JSR     SINVAL
                  ;
                  ;       'TEMP' = SIN (THETA+A*90)
                  ;
AD3B  85A3        SINVAL  STA     TEMP+2          ; SAVE QUADRANT OFFSET.
AD3D  84A4                STY     TEMP+3
AD3F  A072                LDY     #THETA-DTAB     ; 'ACC' = 'THETA'.
AD41  20A29D              JSR     DLOADA          ; X = 'ACC' - 'DTAB'.

AD44  A95A                LDA     # LOW 90        ; 'TEMP' = 90.
AD46  85A1                STA     TEMP
AD48  A900                LDA     # HIGH 90
AD4A  85A2                STA     TEMP+1

                  ; NORMALIZE THETA TO 0-90 RANGE AND USE TRIG EQUALITIES TO COMPUTE SINE.

AD4C  A021        :SN010  LDY     #TEMP-DTAB      ; IS 'ACC' <= 90. HP
AD4E  20159C              JSR     DCMPI
AD51  F009 ^AD5C          BEQ     :SN020          ; YES.
AD53  9007 ^AD5C          BCC     :SN020          ; YES.

AD55  E6A3                INC     TEMP+2          ; NOT YET -- INCREMENT QUADRANT.
AD57  20429C              JSR     DSUBI           ; 'ACC' = 'ACC' - 90.
AD5A  D0F0 ^AD4C          BNE     :SN010          ; (BRA UNLESS RESULT = 0).

AD5C  A6E2        :SN020  LDX     ACC             ; RESULT IS 0 TO 90 FOR TABLE LOOKUP.
AD5E  A5A3                LDA     TEMP+2          ; QUADRANT A.
AD60  2903                AND     #$03            ; MODULO 4.
AD62  F018 ^AD7C          BEQ     :SN100          ; QUADRANT 0.

AD64  C901                CMP     #1
AD66  D008 ^AD70          BNE     :SN040

AD68  A95A                LDA     #90             ; QUADRANT 1.
AD6A  E5E2                SBC     ACC
AD6C  AA                  TAX
AD6D  4C7CAD              JMP     :SN100

AD70  C902        :SN040  CMP     #2
AD72  F020 ^AD94          BEQ     :SN150          ; QUADRANT 2.

AD74  A95A                LDA     #90             ; QUADRANT 3.
AD76  E5E2                SBC     ACC
AD78  AA                  TAX
AD79  4C94AD              JMP     :SN150

AD7C  A900        :SN100  LDA     #0              ; GET VALUE FROM TABLE.
AD7E  E057                CPX     #87             ; 87 THRU 90?
AD80  9008 ^AD8A          BCC     :SN120          ; NO -- USE TABLE.

AD82  85A1                STA     TEMP            ; SPECIAL CASE -- FORCE TO 1.0.
AD84  A901                LDA     #1
AD86  85A2                STA     TEMP+1
AD88  D012 ^AD9C          BNE     :SN900          ; (BRA).

AD8A  85A2        :SN120  STA     TEMP+1          ; MSB = 0.
AD8C  BD9FAD              LDA     SINTAB,X
AD8F  85A1                STA     TEMP            ; LSB = VALUE FROM TABLE.
AD91  4C9CAD              JMP     :SN900

AD94  207CAD      :SN150  JSR     :SN100          ; GET VALUE TO 'TEMP' *** RECURSIVE CALL ***.
AD97  A221                LDX     #TEMP-DTAB      ; THEN NEGATE VALUE.
AD99  20F19C              JSR     DNEGI

AD9C  A4A4        :SN900  LDY     TEMP+3
AD9E  60                  RTS


                  ; SINE TABLE VALUES FOR 0 THROUGH 86 DEGREES

      = AD9F      SINTAB = *        ; SIN(X) * 256          X

AD9F  0004090D12          DB   0,4,9,13,18             ; 0-4
ADA4  161B1F2428          DB   22,27,31,36,40          ; 5-9
ADA9  2C31353A3E          DB   44,49,53,58,62          ; 10-14
ADAE  42474B4F53          DB   66,71,75,79,83          ; 15-19
ADB3  585C606468          DB   88,92,96,100,104        ; 20-24
ADB8  6C7074787C          DB   108,112,116,120,124     ; 25-29
ADBD  8084888B8F          DB   128,132,136,139,143     ; 30-34
ADC2  93969A9EA1          DB   147,150,154,158,161     ; 35-39
ADC7  A5A8ABAFB2          DB   165,168,171,175,178     ; 40-44
ADCC  B5B8BBBEC1          DB   181,184,187,190,193     ; 45-49
ADD1  C4C7CACCCF          DB   196,199,202,204,207     ; 50-54
ADD6  D2D4D7D9DB          DB   210,212,215,217,219     ; 55-59
ADDB  DEE0E2E4E6          DB   222,224,226,228,230     ; 60-64
ADE0  E8EAECEDEF          DB   232,234,236,237,239     ; 65-69
ADE5  F1F2F3F5F6          DB   241,242,243,245,246     ; 70-74
ADEA  F7F8F9FAFB          DB   247,248,249,250,251     ; 75-79
ADEF  FCFDFEFEFF          DB   252,253,254,254,255     ; 80-84
ADF4  FFFF                DB   255,255                 ; 85-66


ADF6                      PROC
                  ;
                  ; TMUUT -- TRIPLE PRECISION MULTIPLY
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'EXPSTK' = WORD OF SIGNED DATA
                  ;       'TEMP' = WORD OF SIGNED DATA
                  ;
                  ;       JSR     TMULT
                  ;
                  ;       'GNUMB'+1 = MSB OF RESULT
                  ;       'GNUNB'+0 = MIDDLE OF RESULT
                  ;       'GNUMB'+2 = LSB OF RESULT
                  ;
ADF6  A900        TMULT   LDA     #0              ; CLEAR RESULT REGISTER.
ADF8  8D4905              STA     GNUMB
ADFB  8D4A05              STA     GNUMB+1
ADFE  8D4B05              STA     GNUMB+2
AE01  85A6                STA     TEMP+5          ; SIGN EXTENSION BYTES.
AE03  85A5                STA     TEMP+4

AE05  A5A2                LDA     TEMP+1          ; EXTEND SIGN OF 'TEMP'.
AE07  1002 ^AE0B          BPL     :TM005          ; SIGN IS POSITIVE.

AE09  C6A6                DEC     TEMP+5          ; SIGN IS NEGATIVE.

AE0B  A594        :TM005  LDA     EXPSTK+1        ; EXTEND SIGN OF 'EXPSTK'.
AE0D  1002 ^AE11          BPL     :TM008          ; SIGN IS POSITIVE.

AE0F  C6A5                DEC     TEMP+4          ; SIGN IS NEGATIVE.

AE11  A218        :TM008  LDX     #24             ; SETUP LOOP COUNT.

AE13  06A1        :TM010  ASL     TEMP
AE15  26A2                ROL     TEMP+1
AE17  26A6                ROL     TEMP+5
AE19  9019 ^AE34          BCC     :TM020

AE1B  18                  CLC
AE1C  AD4B05              LDA     GNUMB+2
AE1F  6593                ADC     EXPSTK
AE21  8D4B05              STA     GNUMB+2
AE24  AD4905              LDA     GNUMB+0
AE27  6594                ADC     EXPSTK+1
AE29  8D4905              STA     GNUMB+0
AE2C  AD4A05              LDA     GNUMB+1
AE2F  65A5                ADC     TEMP+4
AE31  8D4A05              STA     GNUMB+1

AE34  CA          :TM020  DEX
AE35  F00C ^AE43          BEQ     :TM090

AE37  0E4B05              ASL     GNUMB+2
AE3A  2E4905              ROL     GNUMB+0
AE3D  2E4A05              ROL     GNUMB+1
AE40  4C13AE              JMP     :TM010

AE43  60          :TM090  RTS




AE44                      PROC
                  ;
                  ; TADDI -- TRIPLE PRECISION ADDITION
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       X = DTAB OFFSET
                  ;
                  ;       JSR     TADDI
                  ;
                  ;       DTAB(X) = DTAB(X) + 'GNUMB'
                  ;
                  ; NOTE: MSB IS DTAB(X+1), MIDDLE IS DTAB(X+0), LSB IS DTAB(X+2)
                  ;
AE44  18          TADDI   CLC
AE45  B582                LDA     DTAB+2,X
AE47  6D4B05              ADC     GNUMB+2
AE4A  9582                STA     DTAB+2,X
AE4C  B580                LDA     DTAB+0,X
AE4E  6D4905              ADC     GNUMB
AE51  9580                STA     DTAB+0,X
AE53  B581                LDA     DTAB+1,X
AE55  6D4A05              ADC     GNUMB+1
AE58  9581                STA     DTAB+1,X
AE5A  60                  RTS


AE5B                      PROC
                  ;
                  ; QMULT -- 16 * 16 YIELDING 32 BIT SIGNED MULTIPLY
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'GACC' = 2 BYTE MULTIPLICAND.
                  ;       Y = DTAB OFFSET TO 2 BYTE MULTIPLIER.
                  ;
                  ;       JSR     QMULT
                  ;
                  ;       'GACC'[4 BYTE] = 'GACC'[2 BYTE] * 'DTAB'(Y)[2 BYTE]
                  ;
AE5B  A204        QMULT   LDX     #4

AE5D  B5CD        :QM010  LDA     GACC-1,X
AE5F  95D1                STA     GTEMP-1,X
AE61  A900                LDA     #0
AE63  95CD                STA     GACC-1,X
AE65  95D5                STA     GTEMP2-1,X
AE67  CA                  DEX
AE68  D0F3 ^AE5D          BNE     :QM010

AE6A  B98000              LDA     DTAB,Y
AE6D  85D6                STA     GTEMP2
AE6F  B98100              LDA     DTAB+1,Y
AE72  85D7                STA     GTEMP2+1
AE74  1006 ^AE7C          BPL     :QM015

AE76  A9FF                LDA     #-1             ; EXTEND SIGN.
AE78  85D8                STA     GTEMP2+2
AE7A  85D9                STA     GTEMP2+3

AE7C  A5D3        :QM015  LDA     GTEMP+1
AE7E  1004 ^AE84          BPL     :QM020
AE80  A9FF                LDA     #-1             ; EXTEND SIGN.
AE82  D002 ^AE86          BNE     :QM022          ; (BRA).

AE84  A900        :QM020  LDA     #0

AE86  85D4        :QM022  STA     GTEMP+2
AE88  85D5                STA     GTEMP+3

AE8A  A220                LDX     #32             ; SETUP LOOP COUNT.

AE8C  06D2        :QM030  ASL     GTEMP           ; LONG SHIFT LEFT.
AE8E  26D3                ROL     GTEMP+1
AE90  26D4                ROL     GTEMP+2
AE92  26D5                ROL     GTEMP+3
AE94  9019 ^AEAF          BCC     :QM040          ; MSB NOT SET

AE96  18                  CLC                     ; BIT SET -- ADD TO PARTIAL
AE97  A5CE                LDA     GACC
AE99  65D6                ADC     GTEMP2
AE9B  85CE                STA     GACC
AE9D  A5CF                LDA     GACC+1
AE9F  65D7                ADC     GTEMP2+1
AEA1  85CF                STA     GACC+1
AEA3  A5D0                LDA     GACC+2
AEA5  65D8                ADC     GTEMP2+2
AEA7  85D0                STA     GACC+2
AEA9  A5D1                LDA     GACC+3
AEAB  65D9                ADC     GTEMP2+3
AEAD  85D1                STA     GACC+3

AEAF  CA          :QM040  DEX                     ; DONE?
AEB0  F00B ^AEBD          BEQ     :QM090          ; YES.

AEB2  06CE                ASL     GACC            ; LONG SHIFT LEFT.
AEB4  26CF                ROL     GACC+1
AEB6  26D0                ROL     GACC+2
AEB8  26D1                ROL     GACC+3
AEBA  4C8CAE              JMP     :QM030

AEBD  60          :QM090  RTS

AEBE                      PROC
                  ;
                  ; QDIV -- 32 DIVIDED BY 16 YIELDING 16 BIT SIGNED DIVIDE.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'GACC' = 4 BYTE DIVIDEND.
                  ;       Y = DTAB OFFSET TO 2 BYTE DIVISOR.
                  ;
                  ;       JSR     QDIV
                  ;       BNE     OVERFLOW
                  ;
                  ;       'GACC'[2 BYTE] = 'GACC'[4 BYTE] / 'DTAB'(Y) [2 BYTE]
                  ;       X = DTAB OFFSET TO 'GACC'
                  ;
      = AEBE      QDIV    = *
AEBE  B98000              LDA     DTAB,Y          ; CHECK FOR DIVIDE BY ZERO.
AEC1  198100              ORA     DTAB+1,Y
AEC4  F066 ^AF2C          BEQ     :QD097

AEC6  A921                LDA     #32+1           ; LOOP COUNT.
AEC8  85A1                STA     TEMP

AECA  A900                LDA     #0
AECC  85D2                STA     GTEMP           ; CLEAR REMAINDER TO START.
AECE  85D3                STA     GTEMP+1

AED0  B98100              LDA     DTAB+1,Y        ; SEE IF DIVISOR IS NEGATIVE.
AED3  85A2                STA     TEMP+1          ; SAVE FOR LATER.
AED5  1008 ^AEDF          BPL     :QD003          ; NO.

AED7  98                  TYA                     ; YES -- NEGATE DIVISOR ...
AED8  AA                  TAX
AED9  20F19C              JSR     DNEGI
AEDC  2036AF              JSR     QNEGA           ; ... & DIVIDEND.

AEDF  A5D1        :QD003  LDA     GACC+3          ; SEE IF DIVIDEND IS NEGATIVE.
AEE1  85A3                STA     TEMP+2          ; SAVE FOR LATER.
AEE3  1003 ^AEE8          BPL     :QD006          ; NO.

AEE5  2036AF              JSR     QNEGA           ; YES -- NEGATE IT.


AEE8  A252        :QD006  LDX     #GTEMP-DTAB
AEEA  18                  CLC
AEEB  26CE        :QD010  ROL     GACC            ; LONG ROTATE LEFT.
AEED  26CF                ROL     GACC+1
AEEF  26D0                ROL     GACC+2
AEF1  26D1                ROL     GACC+3
AEF3  26D2                ROL     GTEMP           ; REMAINDER = 2 + NEW BIT.
AEF5  26D3                ROL     GTEMP+1

AEF7  C6A1                DEC     TEMP            ; DONE?
AEF9  F00B ^AF06          BEQ     :QD090          ; YES.

AEFB  20159C              JSR     DCMPI           ; IS REMAINDER < DIVISOR?
AEFE  90EB ^AEEB          BCC     :QD010          ; YES.

AF00  20429C              JSR     DSUBI           ; NO -- CORRECT FOR THAT.
AF03  38                  SEC
AF04  B0E5 ^AEEB          BCS     :QD010          ; (BRA).

AF06  20159C      :QD090  JSR     DCMPI
AF09  9007 ^AF12          BCC     :QD091

AF0B  A24E                LDX     #GACC-DTAB
AF0D  A901                LDA     #1
AF0F  20049D              JSR     DADDS

AF12  A5A3        :QD091  LDA     TEMP+2          ; DONE -- SEE IF RESULT IS TO BE NEGATED?
AF14  1003 ^AF19          BPL     :QD093          ; NO.

AF16  2036AF              JSR     QNEGA           ; YES.

AF19  A5A2        :QD093  LDA     TEMP+1          ; SEE IF DIVISOR WAS NEGATED AT BEGINNING.
AF1B  1005 ^AF22          BPL     :QD096          ; NO.

AF1D  98                  TYA
AF1E  AA                  TAX
AF1F  20F19C              JSR     DNEGI           ; YES -- CORRECT FOR THAT.

AF22  A24E        :QD096  LDX     #GACC-DTAB      ; AS ADVERTISED.

                  ; CHECK FOR OVERFLOW IN RESULT

AF24  A5CF                LDA     GACC+1          ; CHECK MSB OF USABLE PORTION.
AF26  1009 ^AF31          BPL     :QD098          ; POSITIVE.

AF28  A5D0                LDA     GACC+2
AF2A  25D1                AND     GACC+3

AF2C  C9FF        :QD097  CMP     #-1
AF2E  4C35AF              JMP     :QD099

AF31  A5D0        :QD098  LDA     GACC+2
AF33  05D1                ORA     GACC+3

AF35  60          :QD099  RTS                     ; RETURN WITH CC SET.



AF36                      PROC
                  ;
                  ; QNEGA -- 4 BYTE NEGATE
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       JSR     QNEGA
                  ;
                  ;       'GACC'[4 BYTE] = - 'GACC'[4 BYTE]
                  ;

AF36  38          QNEGA   SEC                     ; CLEAR BORROW.
AF37  A900                LDA     #0
AF39  E5CE                SBC     GACC
AF3B  85CE                STA     GACC
AF3D  A900                LDA     #0
AF3F  E5CF                SBC     GACC+1
AF41  85CF                STA     GACC+1
AF43  A900                LDA     #0
AF45  E5D0                SBC     GACC+2
AF47  85D0                STA     GACC+2
AF49  A900                LDA     #0
AF4B  E5D1                SBC     GACC+3
AF4D  85D1                STA     GACC+3
AF4F  60                  RTS

AF50                      PROC
                  ;
                  ; RADDI -- DOUBLE PRECISION ADD WITH ROUND FROM FRACTION
                  ;
AF50  B98200      RADDI   LDA     DTAB+2,Y        ; GET FRACTION.
AF53  2A                  ROL     A               ; MSB OF FRACTION TO CARRY.
AF54  4C339C              JMP     DADDIX

AF57                      PROC
                  ;
                  ; RSUBI -- DOUBLE PRECISION SUBTRACT WITH BORROW FROM FRACTION.
                  ;
AF57  B98200      RSUBI   LDA     DTAB+2,Y        ; GET FRACTION.
AF5A  4980                EOR     #$80            ; INVERT MSB OF FRACTION
AF5C  2A                  ROL     A               ; INVERTED MSB TO CARRY.
AF5D  4C439C              JMP     DSUBIX


AF60                      PROC
                  ; GPINIT -- INITIALIZE GRAPHICS PARAMETERS (X, Y, THETA & PEN COLOR)

AF60  A900        GPINIT  LDA     #0              ; PEN = ERASE AND DOWN.
AF62  8D1305              STA     PEN

AF65  A910                LDA     #SPLIT          ; FORCE SPLIT SCREEN.
AF67  8D5205              STA     SPLTSC

AF6A  A908                LDA     #EFREE          ; FREE EDGE TURTLE.
AF6C  8D5E05              STA     EDGRUL

AF6F  A907                LDA     #SCNMOD         ; SET DEFAULT SCREEN MODE
AF71  8D3705              STA     GSMODE

AF74  60                  RTS

AF75                      PROC
                  ;
                  ; DFCLRS -- SET DEFAULT COLORS
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       GSMODE     = GRAPHICS MODE
                  ;
                  ;       JSR     DFCLRS
                  ;
                  ;       'PEN'      = 0
                  ;       'NXTCLR'   = 1
                  ;       'PNCLRS'   = DEFAULT VALUES
                  ;       COLOR REGS = DEFAULT VALUES
                  ;
AF75  A200        DFCLRS  LDX     #0              ; BACKGROUND ...
AF77  8E1305              STX     PEN
AF7A  A901                LDA     #CBLACK         ; ... BLACK
AF7C  20F7A4              JSR     SETCLR

AF7F  A201                LDX     #1              ; PEN #1 ...
AF81  8EBA05              STX     NXTCLR
AF84  A942                LDA     #CRED           ; ... RED.
AF86  20F7A4              JSR     SETCLR

AF89  A202                LDX     #2              ; PEN #2 ...
AF8B  A91A                LDA     #CYELLO         ; ... YELLOW.
AF8D  20F7A4              JSR     SETCLR

AF90  A203                LDX     #3              ; PEN #3 ...
AF92  A984                LDA     #CBLUE          ; ... BLUE.
AF94  20F7A4              JSR     SETCLR
AF97  60                  RTS




AF98                      PROC
                  *
                  *  ENTRY POINT FOR FILL ROUTINE:
                  *
                  *  THE FOLLOWING PARAMETERS MUST BE SET ON ENTRY:
                  *
                  *  GSMODE=GRAPHIC MODE INDEX
                  *  FCOLOR=FILL COLOR
                  *  ROWCRS,COLCRS=STARTING COORDINATES
                  *  MAXROW,MAXCOL=MODE DEPENDENT VALUES
                  *  FSTACK = FILL STACK BASE ADDRESS
                  *

AF98              FLOOD                   ;ROUTINE ENTRY POINT
AF98  A5B0                LDA     S1H             ; INITIALIZE FLOODSTACK POINTER.
AF9A  85F4                STA     FSTACK
AF9C  A5B1                LDA     S1H+1
AF9E  85F5                STA     FSTACK+1
                  *
                  *  SAVE STARTING COORDINATES
                  *
AFA0  A554                LDA     ROWCRS
AFA2  8DA005              STA     SAVROW
AFA5  A555                LDA     COLCRS
AFA7  8DA105              STA     SAVCOL
AFAA  A556                LDA     COLCRS+1
AFAC  8DA205              STA     SAVCOL+1

AFAF  AE3705              LDX     GSMODE          ; MASK FCOLOR DOWN TO RANGE.
AFB2  AD9B05              LDA     FCOLOR
AFB5  3DF6B7              AND     DATMSK,X
AFB8  8D9B05              STA     FCOLOR
                  *
                  *  READ DATA AT STARTING COORDINATES
                  *  SAVE AS " FIELD COLOR"
                  *
AFBB  209FAA              JSR     CNVRT           ; GET ADDRESS
                  *
AFBE  ADB105              LDA     DMASK
AFC1  31F6                AND     (ADRESS),Y

AFC3  4EB005      :FIL02  LSR     SHFAMT
AFC6  B003 ^AFCB          BCS     :FIL03
AFC8  4A                  LSR     A
AFC9  90F8 ^AFC3          BCC     :FIL02

AFCB  8D9C05      :FIL03  STA     FLDCLR          ; FIELD COLOR
AFCE  CD9B05              CMP     FCOLOR          ; SAME AS FILL COLOR?
AFD1  D003 ^AFD6          BNE     :FIL3D          ; NO.
AFD3  4C26B2              JMP     :FIL90          ; YES -- ALL DONE.
                  *
AFD6  2056B2      :FIL3D  JSR     FPLOT           ;PLOT INITIAL POINT
                  *
                  *
AFD9  20B8B2              JSR     TSTROW          ;TEST ROW

AFDC  2C9E05              BIT     ROWFLG
AFDF  1006 ^AFE7          BPL     :FIL04 ; NOT ROW 0
                  *
                  *  IF STARTING ROW = 0 THEN BEGIN
                  *  ALGORITHM IN THE DOWN DIRECTION
                  *
AFE1  A901                LDA     #DOWN
AFE3  8597                STA     ROWINC
AFE5  D004 ^AFEB          BNE     :FIL05

                  *
                  *  STARTING ROW > 0, BEGIN ALGORITHM
                  *  IN THE UP DIRECTION
                  *
AFE7  A9FF        :FIL04  LDA     #UP
AFE9  8597                STA     ROWINC
                  *
                  *  PLOT TO STARTING LEFT COLUMN
                  *
AFEB  2093B2      :FIL05  JSR     TSTCOL
AFEE  2C9F05              BIT     COLFLG
AFF1  3010 ^B003          BMI     :FIL07          ;COLCRS=0
                  *
AFF3  204AB2              JSR     DECCOL
AFF6  207CB2              JSR     TSTPIX
AFF9  D005 ^B000          BNE     :FIL06
AFFB  2056B2              JSR     FPLOT
AFFE  B0EB ^AFEB          BCS     :FIL05
                  *
B000  2043B2      :FIL06  JSR     INCCOL
B003  A555        :FIL07  LDA     COLCRS
B005  8DA305              STA     LFTCOL
B008  A556                LDA     COLCRS+1
B00A  8DA405              STA     LFTCOL+1
                  *
                  * RESET START COLUMN
                  *
B00D  ADA105              LDA     SAVCOL
B010  8555                STA     COLCRS
B012  ADA205              LDA     SAVCOL+1
B015  8556                STA     COLCRS+1
                  *
                  * FPLOT TO STARTING RIGHT COLUMN
                  *
B017  2093B2      :FIL08  JSR     TSTCOL
B01A  2C9F05              BIT     COLFLG
B01D  7010 ^B02F          BVS     :FIL10          ;SCREEN EDGE
                  *
B01F  2043B2              JSR     INCCOL
B022  207CB2              JSR     TSTPIX
B025  D005 ^B02C          BNE     :FIL09
B027  2056B2              JSR     FPLOT           ;FILL PIXEL
B02A  B0EB ^B017          BCS     :FIL08
B02C  204AB2      :FIL09  JSR     DECCOL
B02F  A555        :FIL10  LDA     COLCRS
B031  8DA705              STA     RGTCOL
B034  A556                LDA     COLCRS+1
B036  8DA805              STA     RGTCOL+1
                  *
                  *  TEST ROW -- IF TOP OR BOTTOM THEN
                  *              NOTHING REQUIRED ON STACK
                  *
B039  20B8B2              JSR     TSTROW
B03C  AD9E05              LDA     ROWFLG
B03F  D00F ^B050          BNE     :FIL11          ;TOP OR BOTTOM
                  *
                  *  PUSH ONTO FILL STACK --
                  *       ROWCRS
                  *       DIRECTION
                  *       LFTCOL
                  *       RGTCOL
                  *
B041  20D3B2              JSR     REVROW          ;REVERSE ROW/DIRECTION
                  *
B044  20E1B2              JSR     STKROW
B047  20F5B2              JSR     STKLC
B04A  2001B3              JSR     STKRC
                  *
B04D  20D3B2              JSR     REVROW          ;RESTORE
                  *
                  *
                  *  START THE FILL ALGORITHM
                  *
B050  18          :FIL11  CLC                     ;GO TO NEXT ROW
B051  A554                LDA     ROWCRS
B053  6597                ADC     ROWINC
B055  8554                STA     ROWCRS
                  *


B057  2022AC      :FIL12  JSR     GABRTC          ; OPERATOR ABORT?
B05A  D003 ^B05F          BNE     :FIL13          ; NO.
B05C  4C36B2              JMP     :FIL95          ; YES.
                  *
B05F  ADA305      :FIL13  LDA     LFTCOL
B062  8555                STA     COLCRS
B064  ADA405              LDA     LFTCOL+1
B067  8556                STA     COLCRS+1
                  *
B069  207CB2              JSR     TSTPIX
B06C  D062 ^B0D0          BNE     :FIL20          ;BORDER PIXEL
                  *
B06E  2056B2      :FIL14  JSR     FPLOT           ; FILL PIXEL
                  *
B071  A555                LDA     COLCRS          ;SAVE NEW
B073  8DA505              STA     NEWLC           ;LEFT
B076  A556                LDA     COLCRS+1        ;COLUMN
B078  8DA605              STA     NEWLC+1
                  *
B07B  2093B2              JSR     TSTCOL
B07E  2C9F05              BIT     COLFLG
B081  3008 ^B08B          BMI     :FIL15          ;LEFT SCREEN EDGE
                  *
B083  204AB2              JSR     DECCOL
B086  207CB2              JSR     TSTPIX
B089  F0E3 ^B06E          BEQ     :FIL14          ;FIELD PIXEL
                  *
                  *  BOUNDARY ENCOUNTERED
                  *  COMPARE NEWLC TO LFTCOL
                  *
B08B  38          :FIL15  SEC
B08C  ADA305              LDA     LFTCOL
B08F  EDA505              SBC     NEWLC
B092  8595                STA     DELTAC
B094  ADA405              LDA     LFTCOL+1
B097  EDA605              SBC     NEWLC+1
                  *
B09A  D006 ^B0A2          BNE     :FIL16 ;POSSIBLE OPENING
B09C  A595                LDA     DELTAC
B09E  C903                CMP     #3
B0A0  9070 ^B112          BCC     :FIL30
                  *
                  *
                  *  POSSIBLE OPENING -- TEST FOR CLOSURE
                  *
B0A2  20D3B2      :FIL16  JSR     REVROW
B0A5  2043B2      :FIL17  JSR     INCCOL
                  *
B0A8  A556                LDA     COLCRS+1
B0AA  CDA405              CMP     LFTCOL+1
B0AD  D00D ^B0BC          BNE     :FIL18
B0AF  A555                LDA     COLCRS
B0B1  CDA305              CMP     LFTCOL
B0B4  D006 ^B0BC          BNE     :FIL18
                  *
                  * CLOSURE -- LEFT EDGE FOUND
                  * NO AREA TO BE PLACED ON STACK
                  * CONTINUE WITH SEARCH FOR RIGHT EDGE
                  *
B0B6  20D3B2              JSR     REVROW
B0B9  4C12B1              JMP     :FIL30
B0BC  207CB2      :FIL18  JSR     TSTPIX
B0BF  D0E4 ^B0A5          BNE     :FIL17          ;BORDER PIXEL
                  *
                  *  FIELD COLOR FOUND --
                  *  SAVE AREA DEFINITION ON STACK
                  *
B0C1  20E1B2              JSR     STKROW
B0C4  20EBB2              JSR     STKCC           ;CURRENT COLCRS
B0C7  20F5B2              JSR     STKLC           ;LEFT COLUMN
                  *
B0CA  20D3B2              JSR     REVROW
B0CD  4C12B1              JMP     :FIL30

                  *
                  *
                  *  BOUNDARY PIXEL ABOVE/BELOW LEFT COLUMN
                  *  SEARCH RIGHT TO FIND NEW LFTCOL
                  *  IF RGTCOL REACHED W/O FIELD PIXEL,
                  *  THEN AREA IS CLOSED, JUMP TO POP
                  *  STACK
                  *
B0D0  ADA405      :FIL20  LDA     LFTCOL+1
B0D3  CDA805              CMP     RGTCOL+1
B0D6  D00B ^B0E3          BNE     :FIL21
B0D8  ADA305              LDA     LFTCOL
B0DB  CDA705              CMP     RGTCOL
B0DE  D003 ^B0E3          BNE     :FIL21
                  *
                  *  IF LFTCOL=RGTCOL THEN CLOSURE
                  *
B0E0  4CF8B1              JMP     :FIL70
                  *
B0E3  2043B2      :FIL21  JSR     INCCOL
                  *
B0E6  207CB2              JSR     TSTPIX
B0E9  F011 ^B0FC          BEQ     :FIL22
                  *
                  *  COMPARE TO RGTCOL
                  *
B0EB  A556                LDA     COLCRS+1
B0ED  CDA805              CMP     RGTCOL+1
B0F0  D0F1 ^B0E3          BNE     :FIL21
B0F2  A555                LDA     COLCRS
B0F4  CDA705              CMP     RGTCOL
B0F7  D0EA ^B0E3          BNE     :FIL21
B0F9  4CF8B1              JMP     :FIL70          ;CLOSURE
                  *
                  *
                  *  FIELD PIXEL FOUND --
                  *
                  *  FILL PIXEL
                  *  SET NEWLC
                  *  PROCEED TO SEARCH RIGHT FOR RGTCOL
                  *
B0FC  2056B2      :FIL22  JSR     FPLOT
B0FF  A555                LDA     COLCRS
B101  8DA505              STA     NEWLC
B104  8DA905              STA     NEWRC
B107  A556                LDA     COLCRS+1
B109  8DA605              STA     NEWLC+1
B10C  8DAA05              STA     NEWRC+1
B10F  4C37B1              JMP     :FIL34

                  *
                  *  SEARCH RIGHT FROM LFTCOL TO FIND
                  *  NEW RGTCOL
                  *
B112  ADA305      :FIL30  LDA     LFTCOL
B115  8555                STA     COLCRS
B117  8DA905              STA     NEWRC
B11A  ADA405              LDA     LFTCOL+1
B11D  8556                STA     COLCRS+1
B11F  8DAA05              STA     NEWRC+1
                  *
B122  2043B2      :FIL32  JSR     INCCOL
                  *
B125  207CB2              JSR     TSTPIX
B128  D015 ^B13F          BNE     :FIL35          ;BORDER PIXEL
                  *
B12A  2056B2              JSR     FPLOT           ;FILL PIXEL
                  *
B12D  A555                LDA     COLCRS
B12F  8DA905              STA     NEWRC
B132  A556                LDA     COLCRS+1
B134  8DAA05              STA     NEWRC+1
                  *
B137  2093B2      :FIL34  JSR     TSTCOL
B13A  2C9F05              BIT     COLFLG
B13D  50E3 ^B122          BVC     :FIL32          ;NOT RIGHT SCREEN EDGE
                  *
                  *  NEWRC FOUND -- COMPARE TO RGTCOL
                  *
B13F  ADAA05      :FIL35  LDA     NEWRC+1
B142  CDA805              CMP     RGTCOL+1
B145  900C ^B153          BCC     :FIL40
B147  F002 ^B14B          BEQ     :FIL36
B149  B046 ^B191          BCS     :FIL50
                  *
B14B  ADA905      :FIL36  LDA     NEWRC
B14E  CDA705              CMP     RGTCOL
B151  B03E ^B191          BCS     :FIL50
                  *
                  *  NEWRC < RGTCOL
                  *  IF DELTAC > 3 THEN POSSIBLE OPENING
                  *                     IN SAME DIRECTION
                  *
B153  38          :FIL40  SEC
B154  ADA705              LDA     RGTCOL
B157  EDA905              SBC     NEWRC
B15A  8595                STA     DELTAC
B15C  ADA805              LDA     RGTCOL+1
B15F  EDAA05              SBC     NEWRC+1
B162  D009 ^B16D          BNE     :FIL41
B164  A595                LDA     DELTAC
B166  C903                CMP     #3
B168  B003 ^B16D          BCS     :FIL41
B16A  4CD5B1              JMP     :FIL60

                  *
                  *  CHECK FOR CLOSURE
                  *
B16D  2043B2      :FIL41  JSR     INCCOL
B170  A556                LDA     COLCRS+1
B172  CDA805              CMP     RGTCOL+1
B175  D009 ^B180          BNE     :FIL43
B177  A555                LDA     COLCRS
B179  CDA705              CMP     RGTCOL
B17C  F002 ^B180          BEQ     :FIL43
B17E  B00E ^B18E          BCS     :FIL49  ;CLOSURE
                  *
B180  207CB2      :FIL43  JSR     TSTPIX
B183  D0E8 ^B16D          BNE     :FIL41
                  *
                  *  OPENING FOUND -- PUSH AREA
                  *    DEFINITION ON THE STACK
                  *
B185  20E1B2              JSR     STKROW
B188  20EBB2              JSR     STKCC   ;CURRENT COLORS
B18B  2001B3              JSR     STKRC   ;RIGHT COLUMN
                  *
B18E  4CD5B1      :FIL49  JMP     :FIL60
                  *
                  *
                  *  NEWRC >= RGTCOL
                  *  IF DELTAC > 3 THEN POSSIBLE OPENING
                  *                IN THE OPPOSITE DIRECTION
                  *
B191  F042 ^B1D5  :FIL50  BEQ     :FIL60
B193  38                  SEC
B194  ADA905              LDA     NEWRC
B197  EDA705              SBC     RGTCOL
B19A  8595                STA     DELTAC
B19C  ADAA05              LDA     NEWRC+1
B19F  EDA805              SBC     RGTCOL+1
B1A2  D006 ^B1AA          BNE     :FIL51
B1A4  A595                LDA     DELTAC
B1A6  C903                CMP     #3
B1A8  902B ^B1D5          BCC     :FIL60

                  *
                  * POSSIBLE OPENING - CHECK FOR CLOSURE
                  *
B1AA  20D3B2      :FIL51  JSR     REVROW
B1AD  204AB2      :FIL52  JSR     DECCOL
                  *
B1B0  A556                LDA     COLCRS+1
B1B2  CDA805              CMP     RGTCOL+1
B1B5  D00D ^B1C4          BNE     :FIL53
B1B7  A555                LDA     COLCRS
B1B9  CDA705              CMP     RGTCOL
B1BC  D006 ^B1C4          BNE     :FIL53
                  *
                  * CLOSURE
                  *
B1BE  20D3B2              JSR     REVROW
B1C1  4CD5B1              JMP     :FIL60
                  *
B1C4  207CB2      :FIL53  JSR     TSTPIX
B1C7  D0E4 ^B1AD          BNE     :FIL52
                  *
                  *  FIELD COLOR FOUND -- PUSH AREA
                  *   DEFINITION ON THE STACK
                  *
B1C9  20E1B2              JSR     STKROW
B1CC  2001B3              JSR     STKRC   ;RIGHT COLUMN
B1CF  20EBB2              JSR     STKCC   ;CURRENT COLORS
                  *
B1D2  20D3B2              JSR     REVROW
                  *
                  *
                  *  CURRENT ROW FILLED --
                  *   TEST FOR SCREEN EDGES, IF NOT
                  *   THEN RESET LFTCOL AND RGTCOL
                  *   AND JUMP TO START OF ALGORITHM
                  *
B1D5  20B8B2      :FIL60  JSR     TSTROW
B1D8  AD9E05              LDA     ROWFLG          ; SCREEN TOP OR BOTTOM
B1DB  D01B ^B1F8          BNE     :FIL70
                  *
B1DD  ADA505              LDA     NEWLC
B1E0  8DA305              STA     LFTCOL
B1E3  ADA605              LDA     NEWLC+1
B1E6  8DA405              STA     LFTCOL+1
                  *
B1E9  ADA905              LDA     NEWRC
B1EC  8DA705              STA     RGTCOL
B1EF  ADAA05              LDA     NEWRC+1
B1F2  8DA805              STA     RGTCOL+1
                  *
B1F5  4C50B0              JMP     :FIL11
                  *
                  *
                  *  CLOSURE DETERMINED --
                  *  POP FILL STACK FOR OTHER AREAS TO
                  *  BE FILLED
                  *
                  *  SETUP NEW ROW,DIRECTION,LFTCOL,RGTCGL
                  *  JUMP TO START OF ALGORITHM
                  *
B1F8  A274        :FIL70  LDX     #FSTACK-DTAB
B1FA  A030                LDY     #S1H-DTAB
B1FC  20159C              JSR     DCMPI
B1FF  F025 ^B226          BEQ     :FIL90
B201  2012B3              JSR     POPFS
B204  8DA805              STA     RGTCOL+1
B207  2012B3              JSR     POPFS
B20A  8DA705              STA     RGTCOL
B20D  2012B3              JSR     POPFS
B210  8DA405              STA     LFTCOL+1
B213  2012B3              JSR     POPFS
B216  8DA305              STA     LFTCOL
B219  2012B3              JSR     POPFS
B21C  8597                STA     ROWINC
B21E  2012B3              JSR     POPFS
B221  8554                STA     ROWCRS
                  *
B223  4C57B0              JMP     :FIL12
                  *
                  *  FILL FUNCTION COMPLETE
                  *
                  *  RESTORE STARTING CURSOR COORDINATES
                  *  AND RETURN
                  *
B226  ADA005      :FIL90  LDA     SAVROW
B229  8554                STA     ROWCRS
B22B  ADA105              LDA     SAVCOL
B22E  8555                STA     COLCRS
B230  ADA205              LDA     SAVCOL+1
B233  8556                STA     COLCRS+1
                  *
B235  60                  RTS
                  *
                  * FILL FUNCTION ABORT
                  *
B236  A03E        :FIL95  LDY     #GX1-DTAB
B238  20FFAB              JSR     SETCUR
B23B  209FAA              JSR     CNVRT
B23E  A987                LDA     #ABTERR
B240  4C3A7A              JMP     PSTOP


B243                      PROC
                  *
                  *  SUBROUTINES TO SUPPORT THE FILL ROUTINE
                  *
                  *

B243                      PROC
                  *
                  *  INCREMENT COLCRS
                  *
B243  E655        INCCOL  INC     COLCRS
B245  D002 ^B249          BNE     :ICX
B247  E656                INC     COLCRS+1
B249  60          :ICX    RTS
                  *
                  * DECREMENT COLCRS
                  *
B24A  38          DECCOL  SEC
B24B  A555                LDA     COLCRS
B24D  E901                SBC     #1
B24F  8555                STA     COLCRS
B251  B002 ^B255          BCS     :DCX
B253  C656                DEC     COLCRS+1
B255  60          :DCX    RTS
                  *
                  * PLOT DATA POINT AT ROWCRS,COLCRS
                  * ADRESS ALREADY SET BY CONVRT
                  *
B256  ADFF02      FPLOT   LDA     SSFLAG          ; HONOR START/STOP (CTRL-1).
B259  D0FB ^B256          BNE     FPLOT

B25B  ADB105              LDA     DMASK
B25E  8DB005              STA     SHFAMT
B261  AD9B05              LDA     FCOLOR          ; FILL COLOR
B264  4EB005      :FPLT1  LSR     SHFAMT
B267  B003 ^B26C          BCS     :FPLT2
B269  0A                  ASL     A
B26A  90F8 ^B264          BCC     :FPLT1          ;UNCONDITIONAL
B26C  8D9D05      :FPLT2  STA     MSKTMP          ;MASKED DATA
B26F  ADB105              LDA     DMASK
B272  49FF                EOR     #$FF
B274  31F6                AND     (ADRESS),Y
B276  0D9D05              ORA     MSKTMP
B279  91F6                STA     (ADRESS),Y
B27B  60                  RTS                     ;CARRY SET

B27C                      PROC
                  *
                  *  TSTPIX --
                  *    CONVERT ROW,COL TO ADDRESS
                  *    UNMASK DATA BIT(S) COMPARE WITH FIELD
                  *    COLOR RETURN TO TEST CONDITIONS
                  *
B27C  209FAA      TSTPIX  JSR     CNVRT
B27F  ADB105              LDA     DMASK
B282  8DB005              STA     SHFAMT
B285  31F6                AND     (ADRESS),Y
B287  4EB005      :TSTP1  LSR     SHFAMT          ;RIGHT JUSTIFY
B28A  B003 ^B28F          BCS     :TSTP2          ;DATA PIXEL
B28C  4A                  LSR     A
B28D  90F8 ^B287          BCC     :TSTP1          ;UNCONDITIONAL
B28F  CD9C05      :TSTP2  CMP     FLDCLR          ;COMPARE TO FIELD COLOR
B292  60                  RTS

B293                      PROC
                  *
                  *  TSTCOL -- TEST CURSOR COLUMN
                  *  SET COLFLG=$80 FOR COLUMN=0
                  *  SET COLFLG=$40 FOR COLUMN=MAX
                  *
B293  A900        TSTCOL  LDA     #0
B295  8D9F05              STA     COLFLG
                  *
B298  A556                LDA     COLCRS+1
B29A  0555                ORA     COLCRS
B29C  D006 ^B2A4          BNE     :TSTC1
                  *
                  * COLUMN=0
                  *
B29E  A980                LDA     #$80
B2A0  8D9F05              STA     COLFLG
B2A3  60                  RTS
                  *
B2A4  A556        :TSTC1  LDA     COLCRS+1
B2A6  CDAD05              CMP     MAXCOL+1
B2A9  D00C ^B2B7          BNE     :TSTC9
B2AB  A555                LDA     COLCRS
B2AD  CDAC05              CMP     MAXCOL
B2B0  D005 ^B2B7          BNE     :TSTC9
                  *
                  * COLUMN=MAXCOL (RIGHT SCREEN EDGE)
                  *
B2B2  A940                LDA     #$40
B2B4  8D9F05              STA     COLFLG
B2B7  60          :TSTC9  RTS


B2B8                      PROC
                  *
                  *  TSTROW -- TEST CURSOR ROW
                  *  SET ROWFLG=$80 FOR ROW=0
                  *  SET ROWFLG=$40 FOR ROW=MAX
                  *
B2B8  A900        TSTROW  LDA     #0
B2BA  8D9E05              STA     ROWFLG
B2BD  18                  CLC
B2BE  A554                LDA     ROWCRS
B2C0  D006 ^B2C8          BNE     :TSTR1
                  *
                  *  ROW=0
                  *
B2C2  A980                LDA     #$80
B2C4  8D9E05              STA     ROWFLG
B2C7  60                  RTS
                  *
B2C8  CDAB05      :TSTR1  CMP     MAXROW
B2CB  9005 ^B2D2          BCC     TSTRWX
                  *
                  *  ROW=MAXROW (BOTTOM SCREEN EDGE)
                  *
B2CD  A940                LDA     #$40
B2CF  8D9E05              STA     ROWFLG
                  *
B2D2  60          TSTRWX  RTS

B2D3                      PROC
                  *
                  *
                  *  REVROW -- REVERSE ROW INCREMENT
                  *            VALUE (CHANGE SIGN)
                  *            AND ADD TO ROWCRS
                  *
B2D3  18          REVROW  CLC
B2D4  A597                LDA     ROWINC
B2D6  49FF                EOR     #$FF
B2D8  6901                ADC     #1
B2DA  8597                STA     ROWINC
B2DC  6554                ADC     ROWCRS
B2DE  8554                STA     ROWCRS
B2E0  60                  RTS


B2E1                      PROC
                  *
                  *  STACK SUBROUTINES
                  *
                  *  STKROW - PUSH ROWCRS,ROWINC ONTO FILL STACK
                  *
B2E1  A554        STKROW  LDA     ROWCRS
B2E3  201FB3              JSR     PUSHFS
B2E6  A597                LDA     ROWINC
B2E8  4C1FB3              JMP     PUSHFS
                  *
                  *  STKCC - PUSH CURRENT COLUMN CURSOR ONTO STACK
                  *
B2EB  A555        STKCC   LDA     COLCRS
B2ED  201FB3              JSR     PUSHFS
B2F0  A556                LDA     COLCRS+1
B2F2  4C1FB3              JMP     PUSHFS
                  *
                  *  STKLC - PUSH LEFT COLUMN ONTO STACK
                  *
B2F5  ADA305      STKLC   LDA     LFTCOL
B2F8  201FB3              JSR     PUSHFS
B2FB  ADA405              LDA     LFTCOL+1
B2FE  4C1FB3              JMP     PUSHFS
                  *
                  *  STKRC - PUSH RIGHT COLUMN ONTO STACK
                  *
B301  ADA705      STKRC   LDA     RGTCOL
B304  201FB3              JSR     PUSHFS
B307  ADA805              LDA     RGTCOL+1
B30A  4C1FB3              JMP     PUSHFS

B30D  A9A4        STKOVF  LDA     #FSOFER
B30F  4C3A7A              JMP     PSTOP
                  ;
                  ; POPFS -- POP ONE BYTE FROM STACK
                  ;
B312  A5F4        POPFS   LDA     FSTACK ; FSTACK := FSTACK-1.
B314  D002 ^B318          BNE     :POP10
B316  C6F5                DEC     FSTACK+1
B318  C6F4        :POP10  DEC     FSTACK
B31A  A000                LDY     #0
B31C  B1F4                LDA     (FSTACK),Y
B31E  60                  RTS
                  ;
                  ; PUSHFS -- PUSH ONE BYTE TO STACK.
                  ;
B31F  A4F5        PUSHFS  LDY     FSTACK+1
B321  C4B3                CPY     S2L+1
B323  B0E8 ^B30D          BCS     STKOVF

B325  A000                LDY     #0
B327  91F4                STA     (FSTACK),Y

B329  E6F4                INC     FSTACK          ; FSTACK := FSTACK+1
B32B  D002 ^B32F          BNE     :PSH90

B32D  E6F5                INC     FSTACK+1

B32F  60          :PSH90  RTS

                  *
                  *  TABLES
                  *
                  *  DIV2TR = NUMBER OF SHIFTS FOR COLUMN CURSOR
                  *           (INDICATES PIXELS PER BYTE)
                  *  DMASKT = TABLE OF PIXEL MASKS
                  *
                  *
                  *        DINDEX    ANTIC MODE   BYTSML   DIV2TB
                  *
                  *          0           2          40        0
                  *          1           6          20        0
                  *          2           7          20        0
                  *          3           8          10        2
                  *          4           9          10        3
                  *          5           A          20        2
                  *          6           8          20        3
                  *          7           D          40        2
                  *          8           F          40        3
                  *          9        GTIA 1        40        1
                  *          A        GTIA 2        40        1
                  *          B        GTIA 3        40        1
                  *          C           4          40        0
                  *          D           5          40        0
                  *          E           C          20        3
                  *          F           E          40        2
                  *
B330  0000000203  DIV2TB  DB      0,0,0,2,3,2,3,2,3,1,1,1,0,0,3,2
                  *
B340  00FFF00F    DMASKT  DB      $00,$FF,$F0,$0F
B344  C0300C03            DB      $C0,$30,$0C,$03
B348  80402010            DB      $80,$40,$20,$10
B34C  08040201            DB      $08,$04,$02,$01
                  *


B350                      PROC
                  ;
                  ; ROBOT TURTLE SUBCOMMANDS FOR PILOT GRAPHICS.
                  ;

                  ;
                  ; RBINIT -- INITIALIZE 'ROBOT TURTLE'
                  ;
B350  AD0305      PBINIT  LDA     RBVECT+1        ; ROBOT DRIVER INSTALLED?
B353  F033 ^B388          BEQ     :RI099          ; NO.
B355  A920                LDA     #RBON           ; INITIALIZE.
B357  8DC705              STA     RBTCMD
B35A  4C25B4              JMP     REXEC           ; EXIT THROUGH DRIVER.


                  ;
                  ; RONOFF -- 'ROBOT ON/OFF' SUBCOMMAND.
                  ;
B35D  AD0305      RONOFF  LDA     RBVECT+1        ; ROBOT DRIVER INSTALLED?
B360  F021 ^B383          BEQ     :RN090          ; NO.
B362  A20A                LDX     #ONOFFX         ; CHECK 'ON' OR 'OFF'.
B364  20AB7C              JSR     SBCMAT
B367  D01C ^B385          BNE     :RN092          ; NOT FOUND -- ERROR.
B369  8A                  TXA                     ; SET CC FOR 'ON'/'QFF'.
B36A  F00F ^B37B          BEQ     :RF020          ; 'OFF'.

                  ; 'ROBOT ON'.

B36C  8EC505              STX     RBTON           ; FLAG 'ROBOT ON'.
B36F  A920                LDA     #RBON           ; INTERNAL COMMAND.
B371  4C1BB4              JMP     RXDRIV          ; RETURN THROUGH DRIVER.

                  ; 'ROBOT OFF'.

                  ; *** EXTERNAL ENTRY FROM 'GEXIT' ***.

B374  AD0305      RBTOFF  LDA     RBVECT+1        ; ROBOT DRIVER INSTALLED?
B377  F00F ^B388          BEQ     :RN099          ; GO -- NOP.
B379  A200                LDX     #0              ; FLAG 'ROBOT OFF'.
B37B  8EC505      :RF020  STX     RBTON
B37E  A900                LDA     #RBOFF          ; INTERNAL COMMAND.
B380  4C1BB4              JMP     RXDRIV          ; RETURN THROUGH DRIVER.

B383              :RH090
B383              :RP090
B383              :RE090
B383  A902        :RN090  LDA     #IVCERR         ; NO 'ROBOT' OR 'OFF'.
B385              :RH092
B385              :RP092
B385              :RE092
B385  4C3A7A      :RN092  JMP     PSTOP
B388              :RI099
B388  60          :RN099  RTS


                  ;
                  ; REYES -- ROBOT 'EYES' SUBCOMMAND.
                  ;

B389  ADC505      REYES   LDA     RBTON           ; IS ROBOT ON?
B38C  F0F5 ^B383          BEQ     :RE090          ; NO -- ERROR.

B38E  A20A                LDX     #ONOFFX         ; CHECK FOR 'ON' OR 'OFF'.
B390  20AB7C              JSR     SBCMAT
B393  D0F0 ^B385          BNE     :RE092          ; NOT FOUND -- ERROR.

B395  A901                LDA     #RBEYES         ; INTERNAL COMMAND.
B397  4C1BB4              JMP     RXDRIV          ; RETURN THROUGH DRIVER.


                  ;
                  ; RPEN -- ROBOT 'RPEN' SUBCOMMAND.
                  ;
B39A  ADC505      RPEN    LDA     RBTON           ; IS ROBOT ON?
B39D  F0E4 ^B383          BEQ     :RP090          ; NO -- ERROR.

B39F  A208                LDX     #UPDWNX         ; CHECK FOR 'UP' OR 'DOWN'.
B3A1  20AB7C              JSR     SBCMAT
B3A4  D0DF ^B385          BNE     :RP092          ; NOT FOUND -- ERROR.

B3A6  8A                  TXA                     ; CONVERT TO 0 (UP)/1 (DOWN).
B3A7  A200                LDX     #0              ; ASSUME UP.
B3A9  C940                CMP     #PCDN
B3AB  D001 ^B3AE          BNE     :RP010          ; UP.
B3AD  E8                  INX                     ; DOWN.

B3AE  A902        :RP010  LDA     #RBPEN          ; INTERNAL COMMAND.
B3B0  4C1BB4              JMP     RXDRIV          ; RETURN THROUGH DRIVER.


                  ;
                  ; RHORN -- ROBOT 'HORN' SUBCOMMAND.
                  ;
                  ; 'RHORN OFF' = 'RHORN 0'.
                  ; 'RHORN ON'  = 'RHORN 1'.
                  ;

B3B3  ADC505      RHORN   LDA     RBTON           ; IS ROBOT ON?
B3B6  F0CB ^B383          BEQ     :RH090          ; NO -- ERROR.
B3B8  A20A                LDX     #ONOFFX         ; CHECK FOR 'ON' OR 'OFF'.
B3BA  20AB7C              JSR     SBCMAT
B3BD  F013 ^B3D2          BEQ     :RH020          ; FOUND IT.

                  ; NOT 'ON' OR 'OFF' - CHECK FOR 0,1,2.

B3BF  206E81              JSR     ATOM            ; GET 'HORN' PARAMETER.
B3C2  D0C1 ^B385          BNE     :RH092          ; ERROR -- RETURN.
B3C4  C902                CMP     #NUM            ; CHECK FOR NUMBER.
B3C6  D0BB ^B383          BNE     :RH090          ; NO -- ERROR.
B3C8  A6B9                LDX     NUMBER+1        ; 0,1,2 VALID.
B3CA  D0B7 ^B383          BNE     :RH090          ; INVALID.
B3CC  A6B8                LDX     NUMBER
B3CE  E003                CPX     #3
B3D0  B0B1 ^B383          BCS     :RH090          ; INVALID.
B3D2  A903        :RH020  LDA     #RBHORN         ; INTERNAL COMMAND.
B3D4  4C1BB4              JMP     RXDRIV          ; RETURN THROUGH DRIVER.


                  ;
                  ; RGO -- ROBOT 'GO' SUBCOMMAND.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       ROBOT TURTLE ON
                  ;       EXPSTK+0,+1 = SIGNED MAGNITUDE.
                  ;       EXECUTE MODE
                  ;
                  ;       JSR     RGO
                  ;

B3D7  A215        RGO     LDX     #EXPSTK+2-DTAB  ; EXPSTK+2,+3 = ABSOLUTE VALUE.
B3D9  A013                LDY     #EXPSTK-DTAB
B3DB  20459A              JSR     DMOVI
B3DE  A980                LDA     #RBFWD          ; ASSUME FORWARD.
B3E0  2496                BIT     EXPSTK+3        ; NOW CHECK SIGN.
B3E2  1005 ^B3E9          BPL     RGO010          ; FORWARD IT IS.
B3E4  20F19C              JSR     DNEGI           ; ABSOLUTE VALUE.
B3E7  A981                LDA     #RBBACK         ; BACK.

                  ; *** EXTERNAL ENTRY FROM 'RTURN' ***.

B3E9  8DC705      RGO010  STA     RBTCMD          ; INTERNAL COMMAND.
B3EC  A595                LDA     EXPSTK+2        ; VALUE.
B3EE  8DC805              STA     RBTPRM
B3F1  A596                LDA     EXPSTK+3
B3F3  8DC905              STA     RBTPRM+1
B3F6  4C25B4              JMP     REXEC           ; RETURN THROUGH DRIVER.


                  ;
                  ; RTURN -- ROBOT 'TURN' SUBCOMMAND.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       ROBOT TURTLE ON
                  ;       EXPSTK+0,+1 = SIGNED MAGNITUDE
                  ;       EXECUTE MODE
                  ;
                  ;       JSR     RTURN
                  ;
B3F9  A215        RTURN   LDX     #EXPSTK+2-DTAB  ; EXPSTK+2,+3 = ABSOLUTE VALUE.
B3FB  A013                LDY     #EXPSTK-DTAB
B3FD  20459A              JSR     DMOVI

B400  A941                LDA     #RBRGHT         ; ASSUME RIGHT.
B402  2496                BIT     EXPSTK+3        ; NOW CHECK SIGN
B404  10E3 ^B3E9          BPL     RGO010          ; RIGHT IT IS.
B406  20F19C              JSR     DNEGI           ; ABSOLUTE VALUE
B409  A940                LDA     #RBLEFT         ; LEFT.
B40B  D0DC ^B3E9          BNE     RGO010


                  ;
                  ; RRDSNS -- ROBOT 'READ SENSORS'.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       JSR     RRDSNS
                  ;
                  ;       RBTSNS = SENSOR VALUES.
                  ;       ;      = SNESOR VALUES.
                  ;

B40D  A980        RRDSNS  LDA     #RBFWD          ; 'GO 0' IS A 'NOP'.
B40F  A200                LDX     #0
B411  8EC905              STX     RBTPRM+1        ; MSB = 0.
B414  201BB4              JSR     RXDRIV          ; UPDATE SENSORS.
B417  ADC605              LDA     RBTSNS          ; AS ADVERTISED.
B41A  60                  RTS



B41B                      PROC
                  ;
                  ; RXDRIV -- INTERFACE TO ROBOT DRIVER.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       A = INTERNAL COMMAND.
                  ;       X = LSB OF INTERNAL PARAMETER.
                  ;
                  ;       JSR RXDRIV
                  ;
                  ;       RETURN WITH 'BEQ' ONLY IF OPERATION COMPLETED.
                  ;       JUMP TO 'PSTOP' IF 'BREAK' OR LOGIC ERROR.
                  ;
                  ;       Y IS PRESERVED.
                  ;
                  ;       CHECKS 'EXEC' FLAG AND RETURNS 'OK' IF 'FALSE'.
                  ;
B41B  8DC705      RXDRIV  STA     RBTCMD          ; INTERNAL COMMAND.
B41E  A592                LDA     EXEC            ; EXECUTE?
B420  F01D ^B43F          BEQ     :RX099          ; NO.
B422  8EC805              STX     RBTPRM          ; LSB (INTERNAL PARAMETER).
                  ; *S*   JMP     REXEC           ; INTERFACE TO DRIVER.


                  ;
                  ; REXEC -- CALL ROBOT DRIVER.
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       'RBTCMD' = INTERNAL COMMAND BYTE.
                  ;       'RBTPRM' = INTERNAL PARAMETER WORD.
                  ;
                  ;       JSR REXEC
                  ;       Y IS PRESERVED.
                  ;
                  ;       RETURN IF OPERATION COMPLETED.
                  ;       JUMP TO 'PSTOP' IF 'BREAK' OR LOGIC ERROR.
                  ;
B425  84A1        REXEC   STY     TEMP            ; SAVE Y.
B427  2040B4              JSR     :RX100          ; 'JSR' TO DRIVER.
B42A  204FB4              JSR     TONES

                  ; Y = 1 (OK); = 128 (BREAK); = 132 (LOGIC ERROR).
                  ; A = ROBOT SENSOR STATE.

B42D  8DC605              STA     RBTSNS
B430  C080                CPY     #128
B432  9007 ^B43B          BCC     :RX090          ; OK.

      = 0000              IF DEBUG
   -                      BEQ     :RX020          ; BREAK.
   -              :RX010  LDA     #INTERR         ; 'BUG'.
   -                      BNE     :RX022
                          ENDIF

B434  A987        :RX020  LDA     #ABTERR         ; BREAK.
B436  A4A1        :RX022  LDY     TEMP            ; RESTORE Y.
B438  4C3A7A              JMP     PSTOP

B43B  A4A1        :RX090  LDY     TEMP            ; RESTORE Y.
B43D  A900                LDA     #0              ; SET CC FOR EXIT.
B43F              :RX099
B43F  60                  RTS

B440              :RX100
      = 0000              IF DEBUG
   -                      LDA     RBVECT+1        ; ROBOT DRIVER INSTALLED?
   -                      BEQ     :RX010          ; NO -- BUG.
                          ENDIF

B440  ADC705              LDA     RBTCMD          ; STACK-3.
B443  48                  PHA
B444  ADC805              LDA     RBTPRM          ; STACK-2.
B447  48                  PHA
B448  ADC905              LDA     RBTPRM+1        ; STACK-1.
B44B  48                  PHA
B44C  6C0205              JMP     (RBVECT)

B44F                      PROC
                  ;
                  ; AUDIO TONE GENERATION PROCESSOR
                  ;
B44F  A208        TONES   LDX     #AUREGS*2       ; SETUP TO SCAN REGISTER ASSIGN TABLE.

B451  BD1305      :TO010  LDA     AUDIOR-2,X      ; POINTER TO VARIABLE.
B454  85B6                STA     POINT
B456  1D1405              ORA     AUDIOR-1,X      ; NULL ENTRY IF RESULT IS ZERO.
B459  F003 ^B45E          BEQ     :TO020
B45B  BD1405              LDA     AUDIOR-1,X      ; FINISH MOVING NON-NULL POINTER.
      = 0000              IF      FALSE
   -                      STA     POINT+1
   -                      BMI     :TO020          ; NUMERIC CONSTANT.

   -                      LDY     #0              ; NOW GET VALUE.
   -                      LDA     (POINT),Y
                          ENDIF

B45E  291F        :TO020  AND     #$1F            ; MODULO 32.
B460  A8                  TAY
B461  B971B4              LDA     AUDTAB,Y        ; GET FREQ FROM TABLE.
B464  9DFED1              STA     AUDF1-2,X       ; PUT IN HARDWARE.
B467  A9A4                LDA     #$A4            ; QUARTER VOLUME.
B469  9DFFD1              STA     AUDC1-2,X
B46C  CA                  DEX
B46D  CA                  DEX
B46E  D0E1 ^B451          BNE     :TO010
B470  60          :TO090  RTS

B471  00          AUDTAB  DB   0 ; REST
B472  F3E6D9CCC1          DB   243,230,217,204,193,182
B478  ACA2999088          DB   172,162,153,144,136,128
B47E  79726C6660          DB   121,114,108,102,96,91
B484  55514C4844          DB   85,81,76,72,68,64
B48A  3C3935322F          DB   60,57,53,50,47,45
B490  2A                  DB   42

B491                      PROC
                  ;
                  ; PILVBL -- DEFERRED VBLANK ROUTINE WHICH READS THE
                  ;           CONSOLE KEYS (START/OPTION/SELECT), DEBOUNCES
                  ;           THEM AND RETURNS THE STATUS IN 'CONKEY'.
                  ;
B491  209AB4      PILVBL  JSR     CONKRD          ; READ CONSOLE KEYS.
B494  207AA5              JSR     TRTLOC          ; VISIBLE TURTLE.
B497  4C62E4              JMP     XITVBV          ; EXIT VBLANK.

B49A  AD6505      CONKRD  LDA     CSTATE          ; IDLE STATE?
B49D  D01C ^B4BB          BNE     :CK010          ; NO.

B49F  AD1FD0              LDA     CONSOL          ; YES -- KEY PRESSED?
B4A2  2907                AND     #ANYKEY
B4A4  C907                CMP     #ANYKEY
B4A6  F03E ^B4E6          BEQ     :CK090          ; NO -- ALL DOME.

B4A8  4907                EOR     #ANYKEY         ; INVERT BIT SENSE.
B4AA  8D4405              STA     CONKEY          ; SAVE FOR 'MLOOP'.
B4AD  EE6505              INC     CSTATE          ; GO TO STATE 1.
B4B0  A90C                LDA     #$0C            ; PUT RETURN CODE IN 'CH'.
B4B2  8DFC02              STA     CH
B4B5  A905                LDA     #5              ; ACTIVATE TIMER.
B4B7  8D2002              STA     CDTMV5
B4BA  60                  RTS

B4BB  C901        :CK010  CMP     #1              ; KEY DOWN DEBOUNCE STATE?
B4BD  D009 ^B4C8          BNE     :CK020          ; NO.

B4BF  AD2002              LDA     CDTMV5          ; YES -- DEBOUNCE DONE?
B4C2  D022 ^B4E6          BNE     :CK090          ; NO.

B4C4  EE6505              INC     CSTATE          ; GO TO STATE 2.
B4C7  60                  RTS

B4C8  C902        :CK020  CMP     #2              ; WAIT FOR KEYS UP STATE?
B4CA  D012 ^B4DE          BNE     :CK030          ; NO.

B4CC  AD1FD0              LDA     CONSOL          ; YES -- ALL KEYS UP?
B4CF  2907                AND     #ANYKEY
B4D1  C907                CMP     #ANYKEY
B4D3  D011 ^B4E6          BNE     :CK090          ; NO.

B4D5  EE6505              INC     CSTATE          ; YES -- GO TO STATE 3.

B4D8  A905                LDA     #5              ; ACTIVATE TIMER.
B4DA  8D2002              STA     CDTMV5
B4DD  60                  RTS

B4DE  AD2002      :CK030  LDA     CDTMV5          ; DEBOUNCE DONE?
B4E1  D003 ^B4E6          BNE     :CK090          ; NO.

B4E3  8D6505              STA     CSTATE          ; YES -- GO TO STATE 0.

B4E6  60          :CK090  RTS


B4E7  48          GRDLI   PHA

B4E8  8D0AD4              STA     WSYNC

B4EB  A984                LDA     #CBLUE
B4ED  454F                EOR     COLRSH          ; ATTRACT
B4EF  254E                AND     DRKMSK
B4F1  8D18D0              STA     COLPF2
B4F4  A91A                LDA     #CYELLO
B4F6  454F                EOR     COLRSH          ; ATTRACT
B4F8  254E                AND     DRKMSK
B4FA  8D17D0              STA     COLPF1

B4FD  68                  PLA
B4FE  40                  RTI


B4FF                      PROC
                  ;
                  ; MESSOT -- MESSAGE GENERATOR
                  ;
                  ; CALLING SEQUENCE:
                  ;
                  ;       A = MESSAGE # (INDEX TO INTERNAL TABLE)
                  ;
                  ;       JSR     MESSOT
                  ;
      = B4FF      MESSOT = *
B4FF  297F                AND     #$7F ; MASK OFF SIGN BIT.
B501  0A                  ASL     A
      = 0000              IF      DEBUG
   -                      BEQ     :MO100          ; 0 IS ILLEGAL.

   -                      CMP     #MTSIZ+1
   -                      BCS     :MO100          ; # IS TOO LARGE.
                          ENDIF
B502  AA                  TAX
B503  BD34B5              LDA     MESTAB-2,X      ; GET MESSAGE ADDRESS FROM TABLE.
B506  85A7                STA     TEMP2
B508  BD35B5              LDA     MESTAB-1,X
B50B  85A8                STA     TEMP2+1

B50D  A000                LDY     #0

B50F  B1A7        :MO010  LDA     (TEMP2),Y
B511  F018 ^B52B          BEQ     :MO090          ; DONE (NO EOL AT END).

B513  C8                  INY                     ; BUMP POINTER.

B514  C90D                CMP     #CR             ; INTERNAL CR?
B516  D006 ^B51E          BNE     :MO015          ; NO.

B518  20989F              JSR     NEWLIN
B51B  4C0FB5              JMP     :MO010          ; CONTINUE.

B51E  C99B        :MO015  CMP     #EOL
B520  F006 ^B528          BEQ     :MO020          ; DONE.

B522  208294              JSR     CHOT
B525  4C0FB5              JMP     :MO010

B528  20989F      :MO020  JSR     NEWLIN

B52B  60          :MO090  RTS

      = 0000              IF     DEBUG
   -              :MO100  LSR     A
   -                      STA     ACC             ; PRINT # INSTEAD OF CANNED MESSAGE
   -                      LDA     #0
   -                      STA     ACC+1
   -                      LDA     #14
   -                      JSR     MESSOT          ; *** RECURSIVE CALL ***
   -                      LDX     #ACC-DTAB
   -                      JSR     DECASC
   -                      JMP     NEWLIN
                          ENDIF

B52C                      PROC

B52C  84A9        RDYMES  STY     TEMP2+2         ; SAVE Y REG.
B52E  A901                LDA     #RDYTXT         ; "READY" TEXT.
B530  20FFB4              JSR     MESSOT
B533  A4A9                LDY     TEMP2+2
B535  60                  RTS

B536                      PROC
                  ;
                  ; TABLE OF MESSAGE ADDRESSES
                  ;
B536  90B5        MESTAB  DW   :MES1
B538  97B5                DW   :MES2
B53A  A4B5                DW   :MES3
B53C  BBB5                DW   :MES4
B53E  C7B5                DW   :MES5
B540  CCB5                DW   :MES6
B542  D7B5                DW   :MES7
B544  DDB5                DW   :MES8
B546  E3B5                DW   :MES9
B548  EBB5                DW   :MES10
B54A  F2B5                DW   :MES11
B54C  97B5                DW   :MES12
B54E  FEB5                DW   :MES13
B550  97B5                DW   :MES14
B552  97B5                DW   :MES15
B554  12B6                DW   :MES16
B556  1BB6                DW   :MES17
B558  25B6                DW   :MES18
B55A  32B6                DW   :MES19
B55C  3EB6                DW   :MES20
B55E  45B6                DW   :MES21
B560  54B6                DW   :MES22
B562  62B6                DW   :MES23
B564  88B6                DW   :MES24
B566  8DB6                DW   :MES25
B568  9CB6                DW   :MES26
B56A  A1B6                DW   :MES27
B56C  B1B6                DW   :MES28
B56E  C5B6                DW   :MES29
B570  CAB6                DW   :MES30
B572  E0B6                DW   :MES31
B574  FAB6                DW   :MES32
B576  1CB7                DW   :MES33
B578  35B7                DW   :MES34
B57A  49B7                DW   :MES35
B57C  5CB7                DW   :MES36
B57E  75B7                DW   :MES37
B580  94B7                DW   :MES38
B582  A7B7                DW   :MES39
B584  AEB7                DW   :MES40
B586  BBB7                DW   :MES41
B588  C8B7                DW   :MES42
B58A  CFB7                DW   :MES43
B58C  D6B7                DW   :MES44
B58E  DEB7                DW   :MES45
      = 005A      MTSIZ   = *-MESTAB

B590  0D52454144  :MES1   DB   CR,'READY',EOL

      = FFFF              IF     DEBUG-1
B597              :MES12
B597              :MES14
B597              :MES15
                          ENDIF
B597  5748415427  :MES2   DB   'WHAT',SQUOTE,'S THAT?',0

B5A4  43414E2754  :MES3   DB   'CAN',SQUOTE,'T USE COMMAND HERE',0

B5BB  4449564944  :MES4   DB   'DIVIDE BY 0',0

B5C7  4F4F505300  :MES5   DB   'OOPS',0

B5CC  492F4F2045  :MES6   DB   'I/O ERROR ',0

B5D7  425245414B  :MES7   DB   'BREAK',0

B5DD  202A2A2A20  :MES8   DB   ' *** ',0

B5E3  4E4F20524F  :MES9   DB   'NO ROOM',0

B5EB  5748455245  :MES10  DB   'WHERE?', 0

B5F2  553A20544F  :MES11  DB   'U: TOO DEEP',0


      = 0000              IF     DEBUG
   -              :MES12  DB   'BUG!',0
                          ENDIF

B5FE  4C494E4520  :MES13  DB   'LINE # OUT OF RANGE',0

      = 0000              IF     DEBUG
   -              :MES14  DB   'ERROR #',0

   -              :MES15  DB   'PLEASE SHORTEN',EOL
                          ENDIF

B612  2420564152  :MES16  DB   '$ VARS:',CR,EOL

B61B  0D23205641  :MES17  DB   CR,'# VARS:',CR,EOL

B625  0D55534520  :MES18  DB   CR,'USE STACK:',CR,EOL

B632  0D47522050  :MES19  DB   CR,'GR PARMS:',CR,EOL

B63E  5448455441  :MES20  DB   'THETA=',0

B645  0D0D465245  :MES21  DB   CR,CR,'FREE MEMORY=',0

B654  544F4F204D  :MES22  DB   'TOO MANY I/OS',0

B662  7D41544152  :MES23  DB   CLEAR,'ATARI PILOT (C) COPYRIGHT ATARI 1982',EOL

B688  2D2D3E2000  :MES24  DB   '--> ',0

B68D  43414E2754  :MES25  DB   'CAN',SQUOTE,'T CONTINUE',0

B69C  53544F5000  :MES26  DB   'STOP',0

B6A1  0D43414E27  :MES27  DB   CR,'CAN',SQUOTE,'T RENUMBER',EOL

B6B1  4F5645524C  :MES28  DB   'OVERLAPPING RANGE: ',0

B6C5  20544F2000  :MES29  DB   ' TO ',0

B6CA  0D50524F47  :MES30  DB   CR,'PROGRAM IS UNCHANGED',EOL

B6E0  0D594F5520  :MES31  DB   CR,'YOU ARE ABOUT TO DELETE ',0

B6FA  204C494E45  :MES32  DB   ' LINE(S).',CR,'ARE YOU SURE (Y OR N): ',0

B71C  53504C4954  :MES33  DB   'SPLIT SCREEN NOT ALLOWED',0

B735  4E4F542041  :MES34  DB   'NOT A GRAPHICS MODE',0

B749  0D492F4F20  :MES35  DB   CR,'I/O ASSIGNMENTS:',CR,EOL

B75C  5348414445  :MES36  DB   'SHADE REGION TOO COMPLEX',0

B775  4E4F204D4F  :MES37  DB   'NO MORE PEN COLORS--USE CHANGE',0

B794  414C524541  :MES38  DB   'ALREADY HAVE COLOR',0

B7A7  50454E533A  :MES39  DB   'PENS: ',0

B7AE  4241434B47  :MES40  DB   'BACKGROUND: ',0

B7BB  545552544C  :MES41  DB   'TURTLE PEN: ',0

B7C8  4D4F44453A  :MES42  DB   'MODE: ',0

B7CF  454447453A  :MES43  DB   'EDGE: ',0

B7D6  5350454544  :MES44  DB   'SPEED: ',0

B7DE  57414C4C53  :MES45  DB   'WALLS: ',0
                          EPROC


                  ;
                  ; GRAPHICS TABLES
                  ;

                  ;
                  ; MODE CHARACTERISTICS (BY MODE)
                  ;
      = 0000      NG      =    0                  ; NOT ALLOWED
      = 0080      FO      =    $80                ; ALLOWED BUT NO SPLIT SCREEN (FULL ONLY)
      = 0090      SC      =    FO+SPLIT           ; ALLOWED WITH SPLIT SCREEN.

B7E6  000000      GCHAR   DB   NG,NG,NG
B7E9  9090909090          DB   SC,SC,SC,SC,SC,SC,FO,FO,FO
B7F2  00009090            DB   NG,NG,SC,SC

                  ;
                  ; PIXEL WIDTH MASKS
                  ;
B7F6  FFFFFF      DATMSK  DB   $FF,$FF,$FF
B7F9  0301030103          DB   3,1,3,1,3,1,$F,$F,$F
B802  FFFF0103            DB   $FF,$FF,1,3

                  ; NUMBER OF FOREGROUND COLORS

B806  000404      COLRS   DB   0,4,4
B809  0301030103          DB   3,1,3,1,3,1,15,8,15
B812  00000103            DB   0,0,1,3

                  ; SCREEN CENTER OFFSETS

B816  1300090009  XCENTR  DW   19,9,9
B81C  1300270027          DW   19,39,39,79,79,159,39,39,39
B82E  130013004F          DW   19,19,79,79

B836  0B000B0005  YCENTR  DW   11,11,5
B83C  0B00170017          DW   11,23,23,47,47,95,95,95,95
B84E  0B0005005F          DW   11,5,95,95

                  ; SCREEN BOUNDARIES FOR FILL

B856  2600120012  COLMAX  DW   38,18,18
B85C  26004E004E          DW   38,78,78,158,158,318,78,78,78
B86E  260026009E          DW   38,38,158,158

B876  160016000A  ROWMAX  DW   22,22,10
B87C  16002E002E          DW   22,46,46,94,94,190,190,190,190
B88E  16000A00BE          DW   22,10,190,190

                  ; TEXT SCREEN MARGINS

B896  020000      LMRGTB  DB   2,0,0              ; LEFT MARGINS.
B899  271313      RMRGTB  DB   39,19,19           ; RIGHT MARGINS

                  ; COLOR CLOCKS PER HORIZONTAL UNIT FOR MODES 0 - 15.

B89C  080808      CCPXTB  DB   8,8,8
B89F  0402020101          DB   4,2,2,1,1,0,2,2,2  ; (0 = 1/2)
B8A8  04040101            DB   4,4,1,1

                  ; SCAN LINES PER CURSOR VERTICAL UNIT FOR MODES 0 - 15.

B8AC  100810      SLPYTB  DB   16,8,16
B8AF  0804040202          DB   8,4,4,2,2,1,1,1,1  ; (0 = 1/2)
B8B8  08100101            DB   8,16,1,1

                  ; THIS IS THE NUMBER OF LEFT SHIFTS NEEDED TO MULTIPLY COLORS
                  ; BY # BYTES/ROW.  (ROWCRS*5)/(2*DHLINE)

B8BC  030202      DHLINE  DB   3,2,2
B8BF  0101020203          DB   1,1,2,2,3,3,3,3,3
B8C8  03030203            DB   3,3,2,3

                  ;

B8CC  00010307    HMASK   DB   0,1,3,7

                  ; OFFSETS TQ DISPLAY LIST INTERRUPT BYTE FOR SPLIT SCREEN.

B8D0  000000      DLIOFF  DB   0,0,0
B8D3  182C2C5454          DB   24,44,44,84,84,166,0,0,0
B8DC  0000A4A6            DB   0,0,164,166

                  ; VISIBLE TURTLE Y OFFSET

B8E0  0101000100  TRDY    DB   1,1,0,1,0,0
B8E6  0002010101          DB   0,2,1,1,1,0
B8EC  0000020101          DB   0,0,2,1,1,2
B8F2  0000000100          DB   0,0,0,1,0,1

                  ; VISIBLE TURTLE X OFFSET

B8F8  0303030303  TRDX    DB   3,3,3,3,3,3
B8FE  0303030303          DB   3,3,3,3,3,3
B904  0303030304          DB   3,3,3,3,4,4
B90A  0504040404          DB   5,4,4,4,4,4

                  ; VISIBLE TURTLE PLAYER DATA

B910  10383810BA  VTURT   DB   $10,$38,$38,$10,$BA,$FE,$6C,$EE,$FE,$FE,$7C,$7C,$BA,$82    ; 0

      = 000E      VTHITE  = *-VTURT                                                       ; HEIGHT OF TURTLE REP.

B91E  06066E367C          DB   $06,$06,$6E,$36,$7C,$7C,$EE,$EE,$BE,$7F,$7D,$7D,$04,$0C    ; 1

B92C  3313BFFE7E          DB   $33,$13,$BF,$FE,$7E,$EE,$EE,$FF,$FD,$7D,$3C,$18,$08,$18    ; 2

B93A  30133BBFFC          DB   $30,$13,$3B,$BF,$FC,$7E,$EE,$EE,$FF,$7D,$7D,$38,$08,$18    ; 3

B948  1808BBFF7D          DB   $18,$08,$BB,$FF,$7D,$EE,$EE,$FE,$7C,$7D,$3B,$20,$60,$00    ; 4

B956  3090FB7FFF          DB   $30,$90,$FB,$7F,$FF,$EE,$EC,$7E,$7C,$32,$46,$C0,$00,$00    ; 5

B964  0888B07878          DB   $08,$88,$B0,$78,$78,$EA,$EF,$FA,$78,$78,$B0,$88,$08,$00    ; 6

B972  0000C04632          DB   $00,$00,$C0,$46,$32,$7C,$7E,$EC,$EE,$FF,$7F,$FB,$90,$30    ; 7

B980  0060203B7D          DB   $00,$60,$20,$3B,$7D,$7C,$EE,$EE,$FE,$7D,$FF,$BB,$08,$18    ; 8

B98E  1808387D7D          DB   $18,$08,$38,$7D,$7D,$FF,$EE,$EE,$7E,$FC,$BF,$3B,$13,$30    ; 9

B99C  1808183C7D          DB   $18,$08,$18,$3C,$7D,$FD,$EF,$EE,$FE,$7E,$FE,$BF,$13,$33    ; 10

B9AA  0C047D7D7F          DB   $0C,$04,$7D,$7D,$7F,$AE,$EE,$FE,$7C,$7C,$36,$6E,$06,$06    ; 11

B9B8  82BA7C7CFE          DB   $82,$BA,$7C,$7C,$FE,$EE,$EE,$7C,$FE,$BA,$10,$38,$38,$10    ; 12

B9C6  3020BEBE7E          DB   $30,$20,$BE,$BE,$7E,$6D,$6F,$7F,$3E,$3E,$6C,$76,$60,$60    ; 13

B9D4  1810183CBE          DB   $18,$10,$18,$3C,$BE,$BF,$FF,$6F,$6F,$7E,$7F,$FD,$C8,$CC    ; 14

B9E2  18101CBEBE          DB   $18,$10,$1C,$BE,$BE,$FF,$6F,$6F,$7E,$3F,$FD,$DC,$C8,$0C    ; 15

B9F0  000604DCBE          DB   $00,$06,$04,$DC,$BE,$3E,$77,$77,$7F,$BE,$FF,$DD,$10,$18    ; 16

B9FE  00000362AC          DB   $00,$00,$03,$62,$4C,$3E,$7E,$37,$77,$FF,$FE,$DF,$09,$0C    ; 17

BA0C  10110D1E1E          DB   $10,$11,$0D,$1E,$1E,$5B,$FB,$5F,$1E,$1E,$0D,$11,$10,$00    ; 18

BA1A  0C09DFFEFF          DB   $0C,$09,$DF,$FE,$FF,$77,$37,$7E,$3E,$4C,$62,$03,$00,$00    ; 19

BA28  1810DDFFBE          DB   $18,$10,$DD,$FF,$BE,$77,$77,$7F,$3E,$BE,$DC,$04,$06,$00    ; 20

BA36  0CC8DCFD3F          DB   $0C,$C8,$DC,$FD,$3F,$7E,$77,$77,$FF,$BE,$BE,$1C,$10,$18    ; 21

BA44  CCC8FD7F7E          DB   $CC,$C8,$FD,$7F,$7E,$77,$77,$FF,$BF,$BE,$3C,$18,$10,$18    ; 22

BA52  6060766C3E          DB   $60,$60,$76,$6C,$3E,$3E,$77,$77,$7D,$7E,$BE,$BE,$20,$30    ; 23

                  ; COLOR REGISTER ASSIGNMENTS

BA60                      PROC
BA60  80BA        COLADR  DW   :CSET0             ; MODE 0
BA62  84BA                DW   :CSET1             ; MODE 1
BA64  84BA                DW   :CSET1             ; MODE 2
BA66  84BA                DW   :CSET1             ; MODE 3
BA68  84BA                DW   :CSET1             ; MODE 4
BA6A  84BA                DW   :CSET1             ; MODE 5
BA6C  84BA                DW   :CSET1             ; MODE 6
BA6E  84BA                DW   :CSET1             ; MODE 7
BA70  89BA                DW   :CSET2             ; MODE 8
BA72  8DBA                DW   :CSET3             ; MODE 9
BA74  91BA                DW   :CSET4             ; MODE 10
BA76  8DBA                DW   :CSET3             ; MODE 11
BA78  80BA                DW   :CSET0             ; MODE 12
BA7A  80BA                DW   :CSET0             ; MODE 13
BA7C  84BA                DW   :CSET1             ; MODE 14
BA7E  84BA                DW   :CSET1             ; MODE 15

BA80  00000000    :CSET0  DB   0,0,0,0
BA84  0804050607  :CSET1  DB   8,4,5,6,7          ; BAK, PF0, PF1, PF2 (,PF3 FOR MODES 1 & 2)
BA89  06050000    :CSET2  DB   6,5,0,0            ; PF2, PF 1
BA8D  08000000    :CSET3  DB   8,0,0,0            ; BAK
BA91  0001020304  :CSET4  DB   0,1,2,3,4,5,6,7,8

                          EPROC
      = BA99      PRGEND  =    *-1

BA9A                      END     PILINI