mirror of
https://github.com/cc65/cc65.git
synced 2024-12-25 17:29:50 +00:00
24 lines
529 B
ArmAsm
24 lines
529 B
ArmAsm
;
|
|
; 1998-08-07, Ullrich von Bassewitz
|
|
; 2015-11-23, Greg King
|
|
;
|
|
; unsigned char __fastcall__ revers (unsigned char onoff);
|
|
;
|
|
|
|
.export _revers
|
|
|
|
.importzp RVS
|
|
|
|
.proc _revers
|
|
cmp #$01 ; False or true?
|
|
cla
|
|
ror a ; Either $00 or $80
|
|
ldy RVS ; Load old value
|
|
sta RVS ; Set new value
|
|
tya
|
|
asl a
|
|
rol a ; Either $00 or $01
|
|
clx
|
|
rts
|
|
.endproc
|