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24 lines
529 B
ArmAsm
24 lines
529 B
ArmAsm
;
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; 1998-08-07, Ullrich von Bassewitz
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; 2015-11-23, Greg King
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;
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; unsigned char __fastcall__ revers (unsigned char onoff);
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;
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.export _revers
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.importzp RVS
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.proc _revers
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cmp #$01 ; False or true?
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cla
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ror a ; Either $00 or $80
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ldy RVS ; Load old value
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sta RVS ; Set new value
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tya
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asl a
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rol a ; Either $00 or $01
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clx
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rts
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.endproc
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