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29 lines
900 B
ArmAsm
29 lines
900 B
ArmAsm
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.include "gamate.inc"
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.include "extzp.inc"
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.export _revers
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.proc _revers
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ldx #$00 ; Assume revers off
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tay ; Test onoff
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beq L1 ; Jump if off
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ldx #$ff ; Load on value
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ldy #$00 ; Assume old value is zero
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L1: lda RVS ; Load old value
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stx RVS ; Set new value
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beq L2 ; Jump if old value zero
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iny ; Make old value = 1
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L2: ldx #$00 ; Load high byte of result
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tya ; Load low byte, set CC
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rts
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.endproc
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;-------------------------------------------------------------------------------
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; force the init constructor to be imported
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.import initconio
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conio_init = initconio
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