mirror of
https://github.com/deater/dos33fsprogs.git
synced 2024-07-03 16:29:56 +00:00
50 lines
875 B
ArmAsm
50 lines
875 B
ArmAsm
; 16B herringbone pattern
|
|
|
|
; FIXME: depends on memory init
|
|
|
|
; zero page locations
|
|
GBASL = $26
|
|
GBASH = $27
|
|
|
|
; ROM calls
|
|
HGR2 = $F3D8
|
|
HGR = $F3E2
|
|
HPOSN = $F411
|
|
XDRAW0 = $F65D
|
|
XDRAW1 = $F661
|
|
RESTORE = $FF3F
|
|
|
|
|
|
herring:
|
|
|
|
; $E7 HGR_SCALE is $00 from memory not initialized
|
|
|
|
jsr HGR2 ; Hi-res, full screen ; 3
|
|
; Y=0, A=0 after this call
|
|
|
|
; A and Y are 0 here.
|
|
; X is left behind by the boot process?
|
|
|
|
jsr HPOSN ; set screen position to X= (y,x) Y=(a)
|
|
; saves X,Y,A to zero page
|
|
; after Y= orig X/7
|
|
; A and X are ??
|
|
tiny_loop:
|
|
|
|
; this will be 0 2nd time through loop, arbitrary otherwise
|
|
; lda #1 ; ROT=1
|
|
jsr XDRAW0 ; XDRAW 1 AT X,Y
|
|
; Both A and X are 0 at exit
|
|
; Z flag set on exit
|
|
; Y varies
|
|
|
|
inx ; X=1
|
|
txa ; A=1
|
|
tay ; Y=1
|
|
|
|
bne tiny_loop ; bra
|
|
|
|
; be sure this is at address $0101, easy to set address
|
|
shape_table:
|
|
.byte $04,$00
|