mirror of
https://github.com/cc65/cc65.git
synced 2024-11-16 18:08:04 +00:00
39 lines
1.1 KiB
ArmAsm
39 lines
1.1 KiB
ArmAsm
;
|
|
; 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
|
|
|
|
|