100 SYS700    ;ENABLE PAL 64
110 ;
120 ; PICTURE COMPRESSOR -
130 ; OPTIMIZES HI-RES PICTURE
140 ; AND SAVES ON DISK
150 ; THIS VERSION CONVERTS FILE#8 (R)
160 ; TO FILE#9 (W) WITH SAME LOAD ADDR
170 ;  SYS(*)   COMPRESSES 8 TO 9
180 ;  SYS(*+3) LOADS 8 TO MEMORY
190 ;
200 ;SAVE"@0:COMP1.PAL",8
210 ;
220 .OPT OO
230 *=$C000
240 ;
250 JMP COMPRESS
260 JMP DECOMP
270 ;
280 REPCOUNT .BYTE 1
290 NEWBYT   .BYTE 0
300 PREVBYT  .BYTE 0
310 ST8      .BYTE 0
320 ;
330 PICPTR  =$FB
340 ;KERNEL ROUTINES:
350 CHROUT =$FFD2
360 GETIN  =$FFE4
370 CLOSE  =$FFC3
380 CHKOUT =$FFC9
390 CHKIN  =$FFC6
400 CLRCHN =$FFCC
410 READST =$FFB7
420 ;
430 COMPRESS =*
440 JSR SETIN
450 JSR GETIN   ;START ADDR LO
460 JSR SETOUT
470 JSR CHROUT
480 JSR SETIN
490 JSR GETIN   ;START ADDR HI
500 JSR SETOUT
510 JSR CHROUT
520 JSR SENDPIC ;SEND PICTURE TO FILE
530 JMP FIN
540 ;
550 DECOMP =*
560 JSR SETIN
570 JSR GETIN: STA PICPTR ;LOAD ADDR LO
580 JSR GETIN: STA PICPTR+1 ;"  "  HI
590 LDY #0
600 JSR GETPIC  ;GET PICTURE
610 ;
620 FIN =*
630 JSR CLRCHN
640 LDA #8: JSR CLOSE
650 LDA #9: JSR CLOSE
660 RTS
670 ;
680 ;
690 SENDPIC =*
700 JSR SETIN
710 JSR GETIN
720 STA PREVBYT
730 NEXTOUT =*
740 JSR OUTBYTE
750 LDA ST8
760 BEQ NEXTOUT
770 JSR WRITEREP ;LAST SEQUENCE
780 RTS
790 ;
800 ;
810 OUTBYTE =*
820 JSR SETIN
830 JSR GETIN
840 PHA
850 JSR READST: STA ST8 ;SAVE STATUS
860 PLA
870 STA NEWBYT
880 CMP PREVBYT
890 BNE DIFF
900 ;
910 INC REPCOUNT
920 BNE OK       ;COUNT PAST 255"?
930 DEC REPCOUNT
940 JSR WRITEREP ;WRITE REP CODE
950 OK [178][172]
960 JMP OBFIN
970 ;
980 D[139]F [178][172]    ;[162] BYTE D[139]FERENT
990 LDA REPCOUNT
1000 CMP #6
1010 BCS DOCODE ;M[176]E THAN 4 THE SAME"?
1020 ;NO, JUST PRINT BYTE N TIMES
1030 TAX        ;# REPS FOR LOOP
1040 LDA PREVBYT
1050 CMP #254   ;CTRL BYTE"?
1060 BEQ DOCODE ;YES, HAVE [164] CODE IT
1070 ;
1080 JSR SE[164]UT
1090 LDA PREVBYT
1100 NLP [178][172]
1110 JSR CHROUT
1120 DEX
1130 BNE NLP
1140 LDA #1: STA REPCOUNT
1150 JMP OBFIN
1160 ;
1170 DOCODE [178][172]
1180 JSR WRITEREP
1190 ;
1200 OBFIN [178][172]
1210 LDA [162]BYT
1220 STA PREVBYT
1230 RTS
1240 ;
1250 ;
1260 WRITEREP [178][172]  ;WRITE REPEAT CODE
1270 JSR SE[164]UT
1280 LDA #254     ;SPECIAL [154]ROL BYTE
1290 JSR CHROUT
1300 LDA PREVBYT  ;BYTE [164] REPEAT
1310 JSR CHROUT
1320 LDA REPCOUNT ;NUMBER OF REPS
1330 JSR CHROUT
1340 LDA #1
1350 STA REPCOUNT ;RE[171]INITIALIZE COUNT
1360 RTS
1370 ;
1380 ;
1390 [161]PIC [178][172]    ;UNCOMPRESS
1400 JSR [161]IN
1410 CMP #254     ;REP INDICA[164]R
1420 BEQ [161]REP
1430 ;N[176]MAL BYTE, JUST S[164]RE IT
1440 JSR S[164]RBYT
1450 JMP GPFIN
1460 ;
1470 [161]REP [178][172]    ;REPEAT BYTE N TIMES
1480 JSR [161]IN    ;BYTE [164] REPEAT
1490 PHA
1500 JSR [161]IN    ;# OF REPETITI[145]S
1510 TAX
1520 PLA
1530 REPLP [178][172]
1540 JSR S[164]RBYT  ;STICK IT IN MEM[176]Y
1550 DEX
1560 BNE REPLP    ;DO IT .X TIMES
1570 ;
1580 GPFIN [178][172]
1590 JSR [135]ST   ;CHECK DISK STATUS
1600 BEQ [161]PIC   ;DO UNTIL [128][171]OF[171]FILE
1610 RTS
1620 ;
1630 ;
1640 S[164]RBYT [178][172]   ;PUT .A IN MEM[176]Y
1650 STA (PICPTR),Y
1660 INC PICPTR   ;INC[143]ENT POINTER
1670 BNE SB0
1680 INC PICPTR[170]1
1690 SB0 [178][172]
1700 RTS
1710 ;
1720 ;
1730 SETIN [178][172] ;SET [133] [164] FILE #8
1740 PHA:TXA:PHA
1750 LDX #8
1760 JSR CHKIN
1770 PLA:TAX:PLA
1780 RTS
1790 ;
1800 ;
1810 SE[164]UT [178][172] ;SET OUTPUT [164] FILE #9
1820 PHA:TXA:PHA
1830 LDX #9
1840 JSR CHKOUT
1850 PLA:TAX:PLA
1860 RTS
1870 .[128]