mirror of
https://github.com/deater/dos33fsprogs.git
synced 2024-11-08 16:07:14 +00:00
25 lines
503 B
ArmAsm
25 lines
503 B
ArmAsm
|
;==========
|
||
|
|
; page_flip
|
||
|
|
;==========
|
||
|
|
|
||
|
|
page_flip:
|
||
|
|
lda DISP_PAGE ; 3
|
||
|
|
beq page_flip_show_1 ; 2nt/3
|
||
|
|
page_flip_show_0:
|
||
|
|
bit PAGE0 ; 4
|
||
|
|
lda #4 ; 2
|
||
|
|
sta DRAW_PAGE ; DRAW_PAGE=1 ; 3
|
||
|
|
lda #0 ; 2
|
||
|
|
sta DISP_PAGE ; DISP_PAGE=0 ; 3
|
||
|
|
rts ; 6
|
||
|
|
page_flip_show_1:
|
||
|
|
bit PAGE1 ; 4
|
||
|
|
sta DRAW_PAGE ; DRAW_PAGE=0 ; 3
|
||
|
|
lda #1 ; 2
|
||
|
|
sta DISP_PAGE ; DISP_PAGE=1 ; 3
|
||
|
|
rts ; 6
|
||
|
|
;====================
|
||
|
|
; DISP_PAGE=0 26
|
||
|
|
; DISP_PAGE=1 24
|
||
|
|
|