mirror of
https://github.com/david-schmidt/tlc-apple2.git
synced 2024-09-27 11:01:13 +00:00
80 lines
1.5 KiB
NASM
80 lines
1.5 KiB
NASM
; da65 V2.13.9 - (C) Copyright 2000-2009, Ullrich von Bassewitz
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; Created: 2020-06-04 02:08:05
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.setcpu "6502"
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.org $0300
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; Set up starting address ($C800)
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lda #$00
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ldy #$c8
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sta $3c
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sty $3d
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; Set up ending addresses ($CFFF)
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lda #$ff
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ldy #$cf
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sta $3e
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sty $3f
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; Swap in slot 2
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lda $cfff
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lda $c200
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; Dump it to speaker
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jsr WRITE
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rts
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LFCBA: lda $3C
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cmp $3E
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lda $3D
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sbc $3F
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inc $3C
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bne LFCC8
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inc $3D
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LFCC8: rts
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LEADER:
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LFCC9: ldy #$4B
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jsr LFCDB
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bne LFCC9
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adc #$FE
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bcs LFCC9
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ldy #$21
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LFCD6: jsr LFCDB
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iny
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iny
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LFCDB: dey
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bne LFCDB
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bcc LFCE5
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ldy #$32
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LFCE2: dey
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bne LFCE2
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LFCE5: ldy $C030
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ldy #$2C
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dex
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rts
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WRITE:
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lda #$40
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jsr LFCC9
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ldy #$27
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LFED4: ldx #$00
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eor ($3C,x)
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pha
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lda ($3C,x)
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jsr LFEED
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jsr LFCBA
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ldy #$1D
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pla
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bcc LFED4
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ldy #$22
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jsr LFEED
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beq LFF3A
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LFEED: ldx #$10
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LFEEF: asl a
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jsr LFCD6
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bne LFEEF
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rts
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LFF3A: lda #$DA
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jmp $FDED
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