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37 lines
539 B
ArmAsm
37 lines
539 B
ArmAsm
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;
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; Maciej 'YTM/Elysium' Witkowiak
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;
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; 27.10.2001
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; unsigned char revers (unsigned char onoff);
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.export _revers
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.importzp tmp1
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.include "geossym.inc"
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.include "const.inc"
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_revers:
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tax
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bne L0 ; turn on
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lda #0
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.byte $2c
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L0: lda #SET_REVERSE
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sta tmp1
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lda currentMode
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tax
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and #SET_REVERSE
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tay ; store old value
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txa
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and #%11011111 ; mask out
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ora tmp1 ; set new value
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sta currentMode
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ldx #0
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tya
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beq L1
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lda #1
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L1: rts
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