mirror of
https://github.com/deater/dos33fsprogs.git
synced 2024-11-01 16:04:55 +00:00
31 lines
685 B
ArmAsm
31 lines
685 B
ArmAsm
; Tiny Pastel
|
|
|
|
; draw some scrolling pastel blocks in 16 bytes
|
|
|
|
; by Vince `deater` Weaver <vince@deater.net>, --- dSr ---
|
|
|
|
; zero page locations
|
|
|
|
; ROM calls
|
|
SETCOL = $F864 ; COLOR=A
|
|
PRHEX = $FDE3 ; print hex digit
|
|
COUT = $FDED ; output A to screen
|
|
SETGR = $FB40 ; set lo-res graphics and clear screen
|
|
|
|
.zeropage
|
|
|
|
tiny_xdraw:
|
|
|
|
bit $C050 ; switch to lo-res graphics
|
|
tiny_loop:
|
|
txa
|
|
eor $00,X ; get value from zero page
|
|
jsr SETCOL ; set bottom nibble to top
|
|
jsr COUT ; print to text screen (which is same
|
|
; as lo-res graphics screen) with scroll
|
|
inx
|
|
jmp tiny_loop ; could use bvc to save a byte
|
|
; but we can be sure here and we have
|
|
; a byte to spare
|
|
|