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;
; Ullrich von Bassewitz, 07.08.1998
; modified version for taipan, which doesn't actually
; call revers() any more. only _revflag is needed, see
; rvs_on() and rvs_off() in console.s.
;
; unsigned char revers (unsigned char onoff);
;
.include "atari.inc"
; .export _revers
.export _revflag
;_revers:
; ldx #$00 ; Assume revers off
; tay ; Test onoff
; beq L1 ; Jump if off
; ldx #$80 ; Load on value
;L1: ldy #$00 ; Assume old value is zero
; lda _revflag ; Load old value
; stx _revflag ; Set new value
; beq L2 ; Jump if old value zero
; iny ; Make old value = 1
;L2: ldx #$00 ; Load high byte of result
; tya ; Load low byte, set CC
; rts
.bss
_revflag:
.res 1
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