mirror of https://github.com/a2-4am/4cade.git
104 lines
1.6 KiB
Plaintext
Executable File
104 lines
1.6 KiB
Plaintext
Executable File
;license:MIT
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;(c) 2019 by qkumba
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!cpu 6502
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!to "build/FX.INDEXED/CASCADE",plain
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*=$6000
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!source "src/constants.a"
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ldx #191
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--- jsr WaitForVBL
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lda #$40
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sta $e6
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lsr
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sta $29
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jsr vposn
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lsr $e6
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ldy #$27
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- lda ($26), y
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sta $2000, y
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dey
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bpl -
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stx maxline + 1
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ldx #0
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stx $28
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beq + ;always
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-- lda $26
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sta $28
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lda $27
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sta $29
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+ inx
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jsr vposn
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ldy #$27
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- lda ($28), y
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sta ($26), y
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dey
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bpl -
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maxline
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cpx #$d1 ;SMC
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bne --
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ldy #5
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-- tya
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pha
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dex
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jsr vposn
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lda $26
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sta $28
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lda $27
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eor #$60
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sta $29
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ldy #$27
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- lda ($28), y
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sta ($26), y
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dey
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bpl -
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pla
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tay
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dey
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bne --
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txa
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beq done
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dex
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lda $c000
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bpl ---
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done jmp UnwaitForVBL
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vposn txa
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pha
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and #$c0
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sta $26
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lsr
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lsr
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ora $26
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sta $26
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pla
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sta $27
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asl
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asl
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asl
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rol $27
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asl
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rol $27
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asl
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ror $26
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lda $27
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and #$1f
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ora $e6
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sta $27
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rts
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