990 SYS4096*9:.OPT P,OO:*=49152
1000 JMP RIGHT
1010 JMP LEFT
1020 JMP UP
1030 JMP DOWN
1040 GRAF = $2000
1050 ;################################
1060 ;### ZYL. RIGHT SCROLLING     ###
1070 ;################################
1080 RIGHT LDA #<GRAF:STA $FC
1090 LDX #>GRAF:STX $FD:INX:STX $FB
1100 LDA #<GRAF+312:STA $FA
1110 LDA #8:STA $14:LDA #25:STA $15
1120 A2 LDY #0:LDX #40
1130 LDA ($FA),Y:STA $FE
1140 A1 ROR $FE
1150 LDA ($FC),Y:STA $FE:ROR A
1160 STA ($FC),Y:LDA $FC:CLC:ADC #8
1170 STA $FC:LDA $FD:ADC #0:STA $FD
1180 DEX:BNE A1
1190 DEC $FD:LDA $FC:SEC:SBC #63:STA $FC
1200 LDA $FD:SBC #0:STA $FD
1210 INC $FA:BNE A4:INC $FB
1220 A4 DEC $14:BNE A2
1230 INC $FB:LDA $FA:CLC:ADC #56:STA $FA
1240 LDA $FB:ADC #0:STA $FB
1250 INC $FD:LDA $FC:CLC:ADC #56:STA $FC
1260 LDA $FD:ADC #0:STA $FD
1270 LDA #8:STA $14:DEC $15:BNE A2:RTS
1280 ;################################
1290 ;### ZYL. LEFT SCROLLING      ###
1300 ;################################
1310 LEFT LDA #<GRAF:STA $FA
1320 LDX #>GRAF:STX $FB:INX:STX $FD
1330 LDA #<GRAF+312:STA $FC
1340 LDA #8:STA $14:LDA #25:STA $15
1350 AA2 LDY #0:LDX #40
1360 LDA ($FA),Y:STA $2
1370 AA1 ROL $2
1380 LDA ($FC),Y:STA $2:ROL A:STA ($FC),Y
1390 LDA $FC:SEC:SBC #8:STA $FC
1400 LDA $FD:SBC #0:STA $FD
1410 DEX:BNE AA1
1420 LDA $FC:CLC:ADC #65:STA $FC
1430 LDA $FD:ADC #1:STA $FD
1440 INC $FA:BNE AA4:INC $FB
1450 AA4 DEC $14:BNE AA2
1460 LDA $FC:CLC:ADC #56:STA $FC
1470 LDA $FD:ADC #1:STA $FD
1480 LDA $FA:CLC:ADC #56:STA $FA
1490 LDA $FB:ADC #1:STA $FB
1500 LDA #8:STA $14:DEC $15:BNE AA2
1510 RTS
1520 ;################################
1530 ;### ZYL. UP SCROLLING        ###
1540 ;################################
1550 UP LDX #<GRAF:STX $FA:INX:STX $FC
1560 LDA #>GRAF:STA $FB:STA $FD
1570 LDA #<GRAF-313:STA $14
1580 LDA #>GRAF-313:STA $15
1590 LDA #40:STA $FE
1600 U4 LDX #24:LDY #0
1610 LDA ($FA),Y:PHA
1620 U1 LDA ($FC),Y:STA ($FA),Y
1630 INY:CPY #7:BNE U1
1640 U3 LDA $FA:CLC:ADC #64
1650 STA $FA:LDA $FB:ADC #1:STA $FB
1660 LDA $FC:CLC:ADC #64
1670 STA $FC:LDA $FD:ADC #1:STA $FD
1680 LDA $14:CLC:ADC #64
1690 STA $14:LDA $15:ADC #1:STA $15
1700 LDY #0:LDA ($FA),Y:STA ($14),Y
1710 U2 LDA ($FC),Y:STA ($FA),Y:INY
1720 CPY #7:BNE U2:DEX:BNE U3
1730 DEY:PLA:STA ($FC),Y
1740 LDA $FA:SEC:SBC #248:STA $FA
1750 LDA $FB:SBC #29:STA $FB
1760 LDA $FC:SEC:SBC #248:STA $FC
1770 LDA $FD:SBC #29:STA $FD
1780 LDA $14:SEC:SBC #248:STA $14
1790 LDA $15:SBC #29:STA $15
1800 DEC $FE:BNE U5
1810 RTS
1820 U5 JMP U4
1830 ;################################
1840 ;### ZYL. DOWN SCROLLING      ###
1850 ;################################
1860 DOWN LDX #<GRAF+7680:STX $FA:INX:STX $FC
1870 LDA #>GRAF+7680:STA $FB:STA $FD
1880 LDA #<GRAF+7994:STA $14
1890 LDA #>GRAF+7994:STA $15
1900 LDA #40:STA $FE
1910 D4 LDY #6:LDX #24
1920 LDA ($FC),Y:PHA
1930 D1 LDA ($FA),Y:STA ($FC),Y:DEY
1940 BPL D1
1950 D3 LDA $FA:SEC:SBC #64
1960 STA $FA:LDA $FB:SBC #1:STA $FB
1970 LDA $FC:SEC:SBC #64
1980 STA $FC:LDA $FD:SBC #1:STA $FD
1990 LDA $14:SEC:SBC #64
2000 STA $14:LDA $15:SBC #1:STA $15
2010 LDY #6:LDA ($FC),Y:STA ($14),Y
2020 D2 LDA ($FA),Y:STA ($FC),Y:DEY
2030 BPL D2:DEX:BNE D3
2040 PLA:LDY #0:STA ($FA),Y
2050 LDA $FA:CLC:ADC #8:STA $FA
2060 LDA $FB:ADC #30:STA $FB
2070 LDA $FC:CLC:ADC #8:STA $FC
2080 LDA $FD:ADC #30:STA $FD
2090 LDA $14:CLC:ADC #8:STA $14
2100 LDA $15:ADC #30:STA $15
2110 DEC $FE:BNE D5:RTS
2120 D5 JMP D4