mirror of
https://github.com/deater/dos33fsprogs.git
synced 2024-11-16 23:20:43 +00:00
196 lines
2.7 KiB
ArmAsm
196 lines
2.7 KiB
ArmAsm
;.ifndef scroll_row1
|
|
;scroll_row1 EQU $8A00
|
|
;scroll_row2 EQU $8B00
|
|
;scroll_row3 EQU $8C00
|
|
;scroll_row4 EQU $8D00
|
|
;.endif
|
|
|
|
SCROLL_LENGTH = $61
|
|
;OFFSET = $62
|
|
|
|
|
|
;========================
|
|
; scroll some text
|
|
;========================
|
|
; RLE compressed data in INL/INH
|
|
; CV is Y position to display at
|
|
|
|
gr_scroll:
|
|
lda #0
|
|
sta OFFSET
|
|
|
|
;=======================
|
|
; decompress scroll text
|
|
;=======================
|
|
|
|
jsr decompress_scroll
|
|
|
|
|
|
scroll_loop:
|
|
|
|
ldx #0
|
|
|
|
ldy CV
|
|
lsr
|
|
|
|
lda gr_offsets,Y ; get position
|
|
sta sm1+1
|
|
lda gr_offsets+2,Y ; get position
|
|
sta sm2+1
|
|
lda gr_offsets+4,Y ; get position
|
|
sta sm3+1
|
|
lda gr_offsets+6,Y ; get position
|
|
sta sm4+1
|
|
|
|
|
|
iny
|
|
|
|
clc
|
|
|
|
lda gr_offsets,Y ; get position
|
|
adc DRAW_PAGE
|
|
sta sm1+2
|
|
lda gr_offsets+2,Y ; get position
|
|
adc DRAW_PAGE
|
|
sta sm2+2
|
|
lda gr_offsets+4,Y ; get position
|
|
adc DRAW_PAGE
|
|
sta sm3+2
|
|
lda gr_offsets+6,Y ; get position
|
|
adc DRAW_PAGE
|
|
sta sm4+2
|
|
|
|
ldy OFFSET
|
|
|
|
draw_loop:
|
|
|
|
lda scroll_row1,Y
|
|
sm1:
|
|
sta $400,X
|
|
|
|
lda scroll_row2,Y
|
|
sm2:
|
|
sta $480,X
|
|
|
|
lda scroll_row3,Y
|
|
sm3:
|
|
sta $500,X
|
|
|
|
lda scroll_row4,Y
|
|
sm4:
|
|
sta $580,X
|
|
|
|
iny
|
|
inx
|
|
cpx #40
|
|
bne draw_loop
|
|
|
|
;==================
|
|
; flip pages
|
|
;==================
|
|
|
|
jsr page_flip ; 6
|
|
|
|
;==================
|
|
; delay
|
|
;==================
|
|
|
|
lda #125
|
|
jsr WAIT
|
|
|
|
|
|
;==================
|
|
; loop forever
|
|
;==================
|
|
clc
|
|
lda OFFSET
|
|
adc #40
|
|
cmp SCROLL_LENGTH
|
|
beq done_scrolling
|
|
inc OFFSET
|
|
jmp scroll_loop ; 3
|
|
|
|
done_scrolling:
|
|
rts
|
|
|
|
;=======================
|
|
; decompress scroll
|
|
;=======================
|
|
decompress_scroll:
|
|
ldy #0
|
|
jsr scroll_load_and_increment
|
|
sta SCROLL_LENGTH
|
|
|
|
lda #<scroll_row1
|
|
sta OUTL
|
|
lda #>scroll_row1
|
|
sta OUTH
|
|
|
|
decompress_scroll_loop:
|
|
jsr scroll_load_and_increment ; load compressed value
|
|
|
|
cmp #$A1 ; EOF marker
|
|
beq done_decompress_scroll ; if EOF, exit
|
|
|
|
pha ; save
|
|
|
|
and #$f0 ; mask
|
|
cmp #$a0 ; see if special AX
|
|
beq decompress_scroll_special
|
|
|
|
pla ; note, PLA sets flags!
|
|
|
|
ldx #$1 ; only want to print 1
|
|
bne decompress_scroll_run
|
|
|
|
decompress_scroll_special:
|
|
pla
|
|
|
|
and #$0f ; check if was A0
|
|
|
|
bne decompress_scroll_color ; if A0 need to read run, color
|
|
|
|
decompress_scroll_large:
|
|
jsr scroll_load_and_increment ; get run length
|
|
|
|
decompress_scroll_color:
|
|
tax ; put runlen into X
|
|
jsr scroll_load_and_increment ; get color
|
|
|
|
decompress_scroll_run:
|
|
sta (OUTL),Y
|
|
pha
|
|
|
|
clc ; increment 16-bit pointer
|
|
lda OUTL
|
|
adc #$1
|
|
sta OUTL
|
|
lda OUTH
|
|
adc #$0
|
|
sta OUTH
|
|
|
|
pla
|
|
|
|
dex ; repeat for X times
|
|
bne decompress_scroll_run
|
|
|
|
beq decompress_scroll_loop ; get next run
|
|
|
|
done_decompress_scroll:
|
|
rts
|
|
|
|
|
|
scroll_load_and_increment:
|
|
lda (INL),Y ; load and increment 16-bit pointer
|
|
pha
|
|
clc
|
|
lda INL
|
|
adc #$1
|
|
sta INL
|
|
lda INH
|
|
adc #$0
|
|
sta INH
|
|
pla
|
|
rts
|
|
|