1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
|
;
; Ullrich von Bassewitz, 2003-04-13
;
; void cclearxy (unsigned char x, unsigned char y, unsigned char length);
; void cclear (unsigned char length);
;
.export _cclearxy, _cclear
.import setscrptr
.import rvs
.import popax
.importzp ptr2
.include "atmos.inc"
_cclearxy:
pha ; Save the length
jsr popax ; Get X and Y
sta CURS_Y ; Store Y
stx CURS_X ; Store X
pla ; Restore the length and run into _cclear
_cclear:
tax ; Is the length zero?
beq @L9 ; Jump if done
jsr setscrptr ; Set ptr2 to screen, won't use X
lda #' '
ora rvs
@L1: sta (ptr2),y ; Write one char
iny ; Next char
bne @L2
inc ptr2+1 ; Bump high byte of screen pointer
@L2: dex
bne @L1
@L9: rts
|
