mirror of
https://github.com/deater/dos33fsprogs.git
synced 2024-09-29 08:55:10 +00:00
59 lines
769 B
ArmAsm
59 lines
769 B
ArmAsm
|
;=======================
|
||
|
; HGR2 Clearscreen
|
||
|
;=======================
|
||
|
; note, using BKGND0 for this takes 0x44198 = 278,936 cycles
|
||
|
; unrolled here takes 0x0A501 = 42,241 cycles
|
||
|
|
||
|
hgr2:
|
||
|
bit SET_GR
|
||
|
bit HIRES
|
||
|
bit PAGE2
|
||
|
|
||
|
lda #$40
|
||
|
sta HGR_PAGE
|
||
|
|
||
|
lda #$00
|
||
|
|
||
|
hgr2_clearscreen:
|
||
|
|
||
|
before:
|
||
|
ldy #0
|
||
|
hgr_cls_loop:
|
||
|
sta $2000,Y
|
||
|
sta $2100,Y
|
||
|
sta $2200,Y
|
||
|
sta $2300,Y
|
||
|
sta $2400,Y
|
||
|
sta $2500,Y
|
||
|
sta $2600,Y
|
||
|
sta $2700,Y
|
||
|
sta $2800,Y
|
||
|
sta $2900,Y
|
||
|
sta $2A00,Y
|
||
|
sta $2B00,Y
|
||
|
sta $2C00,Y
|
||
|
sta $2D00,Y
|
||
|
sta $2E00,Y
|
||
|
sta $2F00,Y
|
||
|
sta $3000,Y
|
||
|
sta $3100,Y
|
||
|
sta $3200,Y
|
||
|
sta $3300,Y
|
||
|
sta $3400,Y
|
||
|
sta $3500,Y
|
||
|
sta $3600,Y
|
||
|
sta $3700,Y
|
||
|
sta $3800,Y
|
||
|
sta $3900,Y
|
||
|
sta $3A00,Y
|
||
|
sta $3B00,Y
|
||
|
sta $3C00,Y
|
||
|
sta $3D00,Y
|
||
|
sta $3E00,Y
|
||
|
sta $3F00,Y
|
||
|
iny
|
||
|
bne hgr_cls_loop
|
||
|
|
||
|
after:
|
||
|
rts
|