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;
; Christian Groessler, Apr-2000
;
; void clrscr (void);
;
.export _clrscr
.include "atari.inc"
.importzp ptr1
SCRSIZE = 960 ; 40x24: size of default atari screen
_clrscr:lda SAVMSC ; screen memory
sta ptr1
lda SAVMSC+1
clc
adc #>(SCRSIZE-1)
sta ptr1+1
lda #0 ; screen code of space char
sta OLDCHR
ldy #<(SCRSIZE-1)
ldx #>(SCRSIZE-1)
_clr1: sta (ptr1),y
dey
bne _clr1
sta (ptr1),y
dex
bmi done
dec ptr1+1
dey
jmp _clr1
done: sta COLCRS
sta ROWCRS
rts
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