mirror of https://github.com/stella-emu/stella.git
763 lines
6.0 KiB
NASM
763 lines
6.0 KiB
NASM
;;A bankswitching demo for the EFSC scheme. 16 4K banks accessed by $FFE0-$FFEF
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;;Also includes 128b RAM mapped at $1000 for writes and $1100 for reads
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;;By: Rick Skrbina 4/4/09
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processor 6502
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include "vcs.h"
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include "macro.h"
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Bank0_Color_Read equ Bank0_Color_Write+128
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seg.u SC_RAM
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org $1000
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Bank0_Color_Write ds 1
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seg.u vars
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org $80
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seg bank0
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org $0000
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rorg $F000
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repeat 256
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.byte $00
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repend
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Start0
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nop
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nop
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nop
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CLEAN_START
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Start_Frame
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lda #2
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sta VSYNC
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sta VBLANK
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sta WSYNC
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sta WSYNC
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sta WSYNC
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lsr
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sta VSYNC
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ldy #37
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VerticalBlank
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sta WSYNC
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dey
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bne VerticalBlank
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lda #0
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sta VBLANK
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clc
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lda Bank0_Color_Read
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adc #1
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sta Bank0_Color_Write
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lda Bank0_Color_Read
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sta COLUBK
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ldy #12
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Picture0
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sta WSYNC
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dey
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bne Picture0
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jsr Swch1
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ldy #12
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Picture1
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sta WSYNC
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dey
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bne Picture1
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jsr Swch2
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ldy #12
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Picture2
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sta WSYNC
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dey
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bne Picture2
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jsr Swch3
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ldy #12
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Picture3
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sta WSYNC
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dey
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bne Picture3
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jsr Swch4
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ldy #12
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Picture4
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sta WSYNC
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dey
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bne Picture4
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jsr Swch5
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ldy #12
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Picture5
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sta WSYNC
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dey
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bne Picture5
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jsr Swch6
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ldy #12
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Picture6
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sta WSYNC
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dey
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bne Picture6
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jsr Swch7
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ldy #12
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Picture7
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sta WSYNC
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dey
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bne Picture7
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jsr Swch8
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ldy #12
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Picture8
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sta WSYNC
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dey
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bne Picture8
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jsr Swch9
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ldy #12
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Picture9
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sta WSYNC
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dey
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bne Picture9
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jsr SwchA
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ldy #12
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PictureA
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sta WSYNC
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dey
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bne PictureA
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jsr SwchB
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ldy #12
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PictureB
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sta WSYNC
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dey
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bne PictureB
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jsr SwchC
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ldy #12
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PictureC
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sta WSYNC
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dey
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bne PictureC
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jsr SwchD
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ldy #12
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PictureD
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sta WSYNC
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dey
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bne PictureD
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jsr SwchE
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ldy #12
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PictureE
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sta WSYNC
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dey
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bne PictureE
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jsr SwchF
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ldy #12
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PictureF
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sta WSYNC
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dey
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bne PictureF
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lda #2
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sta VBLANK
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ldy #30
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OverScan
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sta WSYNC
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dey
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bne OverScan
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jmp Start_Frame
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org $0400
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rorg $F400
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Swch1
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lda $FFE1
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Swch2
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lda $FFE2
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Swch3
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lda $FFE3
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rts
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rts
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rts
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rts
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rts
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rts
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rts
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rts
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org $0415
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rorg $F415
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Swch4
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lda $FFE4
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Swch5
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lda $FFE5
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Swch6
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lda $FFE6
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rts
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rts
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rts
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rts
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rts
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rts
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rts
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rts
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org $0430
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rorg $F430
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Swch7
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lda $FFE7
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Swch8
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lda $FFE8
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Swch9
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lda $FFE9
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rts
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rts
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rts
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rts
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rts
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rts
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rts
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rts
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org $0445
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rorg $F445
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SwchA
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lda $FFEA
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SwchB
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lda $FFEB
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SwchC
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lda $FFEC
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rts
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rts
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rts
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rts
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rts
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rts
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rts
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rts
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org $0460
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rorg $F460
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SwchD
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lda $FFED
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SwchE
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lda $FFEE
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SwchF
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lda $FFEF
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rts
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rts
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rts
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rts
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rts
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rts
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rts
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rts
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org $0FFC
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.word Start0
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.byte "00"
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seg bank1
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org $1000
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rorg $F000
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repeat 256
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.byte $00
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repend
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Start1
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lda $FFE0
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Sub1
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lda #$1F
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sta COLUBK
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rts
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org $1400
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rorg $F400
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nop
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nop
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nop
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jsr Sub1
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lda $FFE0
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org $1FFC
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rorg $FFFC
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.word Start1
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.byte "01"
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seg bank2
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org $2000
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rorg $F000
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repeat 256
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.byte $00
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repend
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Start2
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lda $FFE0
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Sub2
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lda #$2F
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sta COLUBK
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rts
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org $2400
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rorg $F400
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nop
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nop
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nop
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nop
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nop
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nop
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jsr Sub2
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lda $FFE0
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org $2FFC
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rorg $FFFC
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.word Start2
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.byte "02"
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seg bank3
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org $3000
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rorg $F000
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repeat 256
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.byte $00
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repend
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Start3
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lda $FFE0
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Sub3
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lda #$3F
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sta COLUBK
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rts
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org $3400
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rorg $F400
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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jsr Sub3
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lda $FFE0
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org $3FFC
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rorg $FFFC
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.word Start3
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.byte "03"
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seg bank4
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org $4000
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rorg $F000
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repeat 256
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.byte $00
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repend
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Start4
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lda $FFE0
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Sub4
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lda #$4F
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sta COLUBK
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rts
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org $4415
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rorg $F415
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nop
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nop
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nop
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jsr Sub4
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lda $FFE0
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org $4FFC
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rorg $FFFC
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.word Start4
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.byte "04"
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seg bank5
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org $5000
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rorg $F000
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repeat 256
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.byte $00
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repend
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Start5
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lda $FFE0
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Sub5
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lda #$5F
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sta COLUBK
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rts
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org $5415
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rorg $F415
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nop
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nop
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nop
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nop
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nop
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nop
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jsr Sub5
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lda $FFE0
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org $5FFC
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rorg $FFFC
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.word Start5
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.byte "05"
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seg bank6
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org $6000
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rorg $F000
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repeat 256
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.byte $00
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repend
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Start6
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lda $FFE0
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Sub6
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lda #$66
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sta COLUBK
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rts
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org $6415
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rorg $F415
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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jsr Sub6
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lda $FFE0
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org $6FFC
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rorg $FFFC
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.word Start6
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.byte "06"
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seg bank7
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org $7000
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rorg $F000
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repeat 256
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.byte $00
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repend
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Start7
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lda $FFE0
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Sub7
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lda #$7F
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sta COLUBK
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rts
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org $7430
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rorg $F430
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nop
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nop
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nop
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jsr Sub7
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lda $FFE0
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org $7FFC
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rorg $FFFC
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.word Start7
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.byte "07"
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seg bank8
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org $8000
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rorg $F000
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repeat 256
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.byte $00
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repend
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Start8
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lda $FFE0
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Sub8
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lda #$8F
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sta COLUBK
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rts
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org $8430
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rorg $F430
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nop
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nop
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nop
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nop
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nop
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nop
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jsr Sub8
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lda $FFE0
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org $8FFC
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rorg $FFFC
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.word Start8
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.byte "08"
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seg bank9
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org $9000
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rorg $F000
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repeat 256
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.byte $00
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repend
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Start9
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lda $FFE0
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Sub9
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lda #$9F
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sta COLUBK
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rts
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org $9430
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rorg $F430
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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jsr Sub9
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lda $FFE0
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org $9FFC
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rorg $FFFC
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.word Start9
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.byte "09"
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seg bankA
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org $A000
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rorg $F000
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repeat 256
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.byte $00
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repend
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StartA
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lda $FFE0
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SubA
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lda #$AF
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sta COLUBK
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rts
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org $A445
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rorg $F445
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nop
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nop
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nop
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jsr SubA
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lda $FFE0
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org $AFFC
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rorg $FFFC
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.word StartA
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.byte "0A"
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seg bankB
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org $B000
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rorg $F000
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repeat 256
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.byte $00
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repend
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StartB
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lda $FFE0
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SubB
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lda #$BF
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sta COLUBK
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rts
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org $B445
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rorg $F445
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nop
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nop
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nop
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nop
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nop
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nop
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jsr SubB
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lda $FFE0
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org $BFFC
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rorg $FFFC
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.word StartB
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.byte "0B"
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seg bankC
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org $C000
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rorg $F000
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repeat 256
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.byte $00
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repend
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StartC
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lda $FFE0
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SubC
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lda #$CF
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sta COLUBK
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rts
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org $C445
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rorg $F445
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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jsr SubC
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lda $FFE0
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org $CFFC
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rorg $FFFC
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.word StartC
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.byte "0C"
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seg bankD
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org $D000
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rorg $F000
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repeat 256
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.byte $00
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repend
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StartD
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lda $FFE0
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SubD
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lda #$DF
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sta COLUBK
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rts
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org $D460
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rorg $F460
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nop
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nop
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nop
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jsr SubD
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lda $FFE0
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org $DFFC
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rorg $FFFC
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.word StartD
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.byte "0D"
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seg bankE
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org $E000
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rorg $F000
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repeat 256
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.byte $00
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repend
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StartE
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lda $FFE0
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SubE
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lda #$EF
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sta COLUBK
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rts
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org $E460
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rorg $F460
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nop
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nop
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nop
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nop
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nop
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nop
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jsr SubE
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lda $FFE0
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org $EFFC
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rorg $FFFC
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.word StartE
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.byte "0E"
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seg bankF
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org $F000
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rorg $F000
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repeat 256
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.byte $00
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repend
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StartF
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lda $FFE0
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SubF
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lda #$FF
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sta COLUBK
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rts
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org $F460
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rorg $F460
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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nop
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jsr SubF
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lda $FFE0
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org $FFFC
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rorg $FFFC
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.word StartF
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.byte "0F"
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