mirror of
https://github.com/deater/dos33fsprogs.git
synced 2024-07-06 07:28:58 +00:00
186 lines
3.0 KiB
ArmAsm
186 lines
3.0 KiB
ArmAsm
; Missing scene
|
|
|
|
; Uses the 40x48d page1/page2 every-1-scanline pageflip mode
|
|
|
|
; by deater (Vince Weaver) <vince@deater.net>
|
|
|
|
missing_intro:
|
|
|
|
;===================
|
|
; init screen
|
|
jsr TEXT
|
|
jsr HOME
|
|
bit KEYRESET
|
|
|
|
;===================
|
|
; init vars
|
|
|
|
lda #0
|
|
sta DRAW_PAGE
|
|
|
|
;=============================
|
|
; setup graphics code
|
|
|
|
jsr create_update_type1
|
|
|
|
;=============================
|
|
; Load graphic page0
|
|
|
|
lda #<k_low
|
|
sta GBASL
|
|
lda #>k_low
|
|
sta GBASH
|
|
lda #$c ; load to $c00
|
|
jsr load_rle_gr
|
|
|
|
lda #4
|
|
sta DRAW_PAGE
|
|
|
|
jsr gr_copy_to_current ; copy to page1
|
|
|
|
; GR part
|
|
bit PAGE1
|
|
bit LORES ; 4
|
|
bit SET_GR ; 4
|
|
bit FULLGR ; 4
|
|
|
|
; jsr wait_until_keypressed
|
|
|
|
|
|
;=============================
|
|
; Load graphic page1
|
|
|
|
lda #<k_high
|
|
sta GBASL
|
|
lda #>k_high
|
|
sta GBASH
|
|
|
|
lda #$c
|
|
|
|
jsr load_rle_gr
|
|
|
|
lda #0
|
|
sta DRAW_PAGE
|
|
|
|
jsr gr_copy_to_current
|
|
|
|
; GR part
|
|
bit PAGE0
|
|
|
|
; jsr wait_until_keypressed
|
|
|
|
|
|
;==============================
|
|
; setup graphics for vapor lock
|
|
;==============================
|
|
|
|
jsr vapor_lock
|
|
|
|
; vapor lock returns with us at beginning of hsync in line
|
|
; 114 (7410 cycles), so with 5070 lines to go
|
|
|
|
; GR part
|
|
bit LORES ; 4
|
|
bit SET_GR ; 4
|
|
bit FULLGR ; 4
|
|
|
|
jsr gr_copy_to_current ; 6+ 9292
|
|
|
|
; 5070 + 4550 = 9620
|
|
; 9292
|
|
; 12
|
|
; 6
|
|
; ====
|
|
; 310
|
|
|
|
; - 3 for jmp
|
|
; 307
|
|
|
|
; Try X=9 Y=6 cycles=307
|
|
|
|
ldy #6 ; 2
|
|
mloopA: ldx #9 ; 2
|
|
mloopB: dex ; 2
|
|
bne mloopB ; 2nt/3
|
|
dey ; 2
|
|
bne mloopA ; 2nt/3
|
|
|
|
jmp missing_display_loop ; 3
|
|
|
|
.align $100
|
|
|
|
;================================================
|
|
; Display Loop
|
|
;================================================
|
|
; each scan line 65 cycles
|
|
; 1 cycle each byte (40cycles) + 25 for horizontal
|
|
; Total of 12480 cycles to draw screen
|
|
; Vertical blank = 4550 cycles (70 scan lines)
|
|
; Total of 17030 cycles to get back to where was
|
|
|
|
; We want to alternate between page1 and page2 every 65 cycles
|
|
; vblank = 4550 cycles to do scrolling
|
|
|
|
|
|
|
|
; want colors 01234567
|
|
; line 0: $X0 to $800
|
|
; line 1: $X1 to $400
|
|
; line 2: $X2
|
|
; line 3: $X3
|
|
; line 4: $4X
|
|
; line 5: $5X
|
|
; line 6: $6X
|
|
; line 7: $7X
|
|
|
|
missing_display_loop:
|
|
|
|
jsr $9000 ; update_type1
|
|
;.include "missing_screen_update.s"
|
|
|
|
;======================================================
|
|
; We have 4550 cycles in the vblank, use them wisely
|
|
;======================================================
|
|
; do_nothing should be
|
|
; 4550
|
|
; -12 jsr/ret to update_type1
|
|
; - 7 check keypress
|
|
; - 3 jmp loop
|
|
;=============
|
|
; 4528
|
|
|
|
|
|
; blah, current code the tight loops are right at a page boundary
|
|
|
|
do_nothing_missing:
|
|
|
|
; want 4528
|
|
|
|
; Try X=4 Y=174 cycles=4525 R3
|
|
|
|
lda TEMP ; nop 3
|
|
|
|
ldy #174 ; 2
|
|
gloop1: ldx #4 ; 2
|
|
gloop2: dex ; 2
|
|
bne gloop2 ; 2nt/3
|
|
dey ; 2
|
|
bne gloop1 ; 2nt/3
|
|
|
|
|
|
lda KEYPRESS ; 4
|
|
bpl missing_no_keypress ; 3
|
|
|
|
rts
|
|
|
|
missing_no_keypress:
|
|
|
|
jmp missing_display_loop ; 3
|
|
|
|
.align $100
|
|
|
|
|
|
.include "k_40_48d.inc"
|
|
|
|
|