mirror of https://github.com/st3fan/ewm.git
57 lines
761 B
ArmAsm
57 lines
761 B
ArmAsm
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.org $8000
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ptr = $06
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page2off = $c054
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page2on = $c055
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kybd = $c000
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strobe = $c010
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main: jsr clear1
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jsr clear2
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loop: lda page2off
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jsr wait
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lda page2on
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jsr wait
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jmp loop
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wait: lda kybd
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cmp #$80
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bcc wait
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sta strobe
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rts
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clear1: lda #$04
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sta ptr+1
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ldy #$00
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sty ptr
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start1: lda #'1'
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loop1: sta (ptr),y
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iny
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bne loop1
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nxt1: inc ptr+1
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lda ptr+1
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cmp #$08
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bcc start1
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rts
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clear2: lda #$08
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sta ptr+1
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ldy #$00
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sty ptr
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start2: lda #'2'
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loop2: sta (ptr),y
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iny
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bne loop2
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nxt2: inc ptr+1
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lda ptr+1
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cmp #$0c
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bcc start2
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rts
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