mirror of
https://github.com/cc65/cc65.git
synced 2024-06-01 13:41:34 +00:00
53dd513176
which included commits to RCS files with non-trunk default branches. git-svn-id: svn://svn.cc65.org/cc65/trunk@3 b7a2c559-68d2-44c3-8de9-860c34a00d81
48 lines
557 B
ArmAsm
48 lines
557 B
ArmAsm
;
|
|
; Christian Groessler, Apr-2000
|
|
;
|
|
; void clrscr (void);
|
|
;
|
|
|
|
.export _clrscr
|
|
|
|
.include "atari.inc"
|
|
|
|
.ifdef DIRECT_SCREEN
|
|
|
|
.importzp ptr1
|
|
|
|
_clrscr:lda SAVMSC ; screen memory
|
|
sta ptr1
|
|
lda SAVMSC+1
|
|
clc
|
|
adc #>(40*24)
|
|
sta ptr1+1
|
|
lda #0 ; screen code of space char
|
|
ldy #<(40*24) ; 40x24: size of default atari screen
|
|
ldx #>(40*24)
|
|
_clr1: sta (ptr1),y
|
|
dey
|
|
bne _clr1
|
|
sta (ptr1),y
|
|
dex
|
|
bmi done
|
|
ldy ptr1+1
|
|
dey
|
|
sty ptr1+1
|
|
ldy #255
|
|
jmp _clr1
|
|
|
|
done: sta COLCRS
|
|
sta ROWCRS
|
|
rts
|
|
|
|
.else
|
|
|
|
.import putchar
|
|
_clrscr:
|
|
lda #ATCLR
|
|
jmp putchar
|
|
|
|
.endif
|