Apple-2-SW/dos33fsprogs
1
0
Fork 0
mirror of https://github.com/deater/dos33fsprogs.git synced 2024-11-04 20:06:09 +00:00
Code Issues Projects Releases Wiki Activity
a6426c1e4f
dos33fsprogs/waterfall/waterfall.s
Vince Weaver 24f1cd4c57 waterfall: more code condensing
2018-10-04 23:07:52 -04:00

1234 lines
20 KiB
ArmAsm
Raw Blame History

; Lo-res cycle-counting water transparency hack
; by deater (Vince Weaver) <vince@deater.net>
; Zero Page
FRAMEBUFFER = $00 ; $00 - $0F
YPOS = $10
YPOS_SIN = $11
CH = $24
CV = $25
GBASL = $26
GBASH = $27
BASL = $28
BASH = $29
MASK = $2E
COLOR = $30
FRAME = $60
MB_VALUE = $91
BIRD_STATE = $E0
BIRD_DIR = $E1
DRAW_PAGE = $EE
LASTKEY = $F1
PADDLE_STATUS = $F2
XPOS = $F3
OLD_XPOS = $F4
TEMP = $FA
TEMPY = $FB
INL = $FC
INH = $FD
OUTL = $FE
OUTH = $FF
; Soft Switches
KEYPRESS= $C000
KEYRESET= $C010
SET_GR = $C050 ; Enable graphics
FULLGR = $C052 ; Full screen, no text
PAGE0 = $C054 ; Page0
PAGE1 = $C055 ; Page1
LORES = $C056 ; Enable LORES graphics
PADDLE_BUTTON0 = $C061
PADDL0 = $C064
PTRIG = $C070
; ROM routines
TEXT = $FB36 ;; Set text mode
HOME = $FC58 ;; Clear the text screen
WAIT = $FCA8 ;; delay 1/2(26+27A+5A^2) us
; location we don't care about
DUMMY = $300
waterfall_demo:
;===================
; init screen
jsr TEXT
jsr HOME
bit PAGE0
;===================
; init vars
lda #0
sta BIRD_DIR
sta BIRD_STATE
sta FRAME
sta OLD_XPOS
lda #4
sta DRAW_PAGE
sta XPOS
;===================
; Mockingboard
jsr mockingboard_init
; Enable channel A tone+noise
ldx #7 ; 2
lda #$36 ; 2
sta MB_VALUE ; 3
jsr write_ay_both ; 6+65
; enable white noise
ldx #6 ; 2
lda #1 ; 2
sta MB_VALUE ; 3
jsr write_ay_both ; 6+65
;===============
; 78
;=============================
; Load foreground to graphic page1 (apple page2)
lda #$0c
sta BASH
lda #$00
sta BASL ; load image to $c00
lda #<waterfall_page1
sta GBASL
lda #>waterfall_page1
sta GBASH
jsr load_rle_gr
jsr gr_copy_to_current ; copy to page1
;=============================
; Load bg to memory
lda #$0c
sta BASH
lda #$00
sta BASL ; load image to $c00
lda #<waterfall_page2
sta GBASL
lda #>waterfall_page2
sta GBASH
jsr load_rle_gr
;==============================
; setup graphics for vapor lock
;==============================
jsr vapor_lock ; 6
; vapor lock returns with us at beginning of hsync in line
; 114 (7410 cycles), so with 5070 lines to go
jsr gr_copy_to_current ; 6+ 9292
; now we have 322 left
; GR part
bit LORES ; 4
bit SET_GR ; 4
bit FULLGR ; 4
; 322 - 12 = 310
; -3 for jmp
; 307
; Try X=9 Y=6 cycles=307
ldy #6 ; 2
wfloopA:ldx #9 ; 2
wfloopB:dex ; 2
bne wfloopB ; 2nt/3
dey ; 2
bne wfloopA ; 2nt/3
jmp display_loop
jump_table:
.word (display_even-1)
.word (display_odd-1)
.word (display_three-1)
.word (display_four-1)
.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
; jump_table
; 38 + display_odd
; we have 3 (the jmp back)
; = 3 cycles that need to be eaten by the vblank
display_loop:
inc FRAME ; 5
lda FRAME ; 3
and #$30 ; 2
; 0011 0000, so more or less div by 16, 3.75Hz
lsr ; 2
lsr ; 2
lsr ; 2
tay ; 2 ; 18
lda jump_table+1,y ; 4
pha ; 3
lda jump_table,y ; 4
pha ; 3
rts ; 6 ; 38
display_loop_return:
vblank:
;======================================================
; We have 4550 cycles in the vblank, use them wisely
;======================================================
; do_nothing should be 4550
; -3 letfover from HBLANK code
; ** -9
; -49 check for keypress
; -2252 copy screen
; -2231 draw sprite
; =============
; 15 cycles
; 15 cycles
inc YPOS ; 5
nop ; 2
nop ; 2
lda YPOS ; 3
lda YPOS ; 3
;=========================
; Clear background
;=========================
jsr gr_copy_row22 ; 6+ 2246
;=========
; 2252
;==========================
; draw bird sprite
;==========================
; 8 prefix
; bird_walk_right= 14 + 2175 2206 (need 17)
; bird_stand_right= 13 + 2190 2206 (need 3)
; bird_walk_left= 15 + 2175 2206 (need 16)
; bird_stand_left= 14 + 2190 2206 (need 2)
; call to sprite 17 postfix
;====================================================
; 2231
lda BIRD_STATE ; 3
and #1 ; 2
ldx BIRD_DIR ; 3
bne bird_left
bird_right:
; 2
cmp #1 ; 2
beq bird_walk_right
; 2
bird_stand_right:
ldx #>bird_rider_stand_right ; 2
ldy #<bird_rider_stand_right ; 2
lda YPOS ; nop=3
jmp draw_bird ; 3
bird_walk_right:
; 3
ldx #>bird_rider_walk_right ; 2
ldy #<bird_rider_walk_right ; 2
jmp kill_less_time ; 3
bird_left:
; 3
cmp #1 ; 2
beq bird_walk_left
bird_stand_left:
; 2
ldx #>bird_rider_stand_left ; 2
ldy #<bird_rider_stand_left ; 2
nop ; nop=2
jmp draw_bird ; 3
bird_walk_left:
; 3
ldx #>bird_rider_walk_left ; 2
ldy #<bird_rider_walk_left ; 2
kill_time:
nop ; 2 ; need to kill 16
kill_less_time:
lda YPOS ; nop=3 ; need to kill 14
lda YPOS ; nop=3
lda YPOS ; nop=3
lda YPOS ; nop=3
nop ; 2
jmp draw_bird ; 3
draw_bird:
stx INH ; 3
sty INL ; 3
lda #22 ; 2
sta YPOS ; 3
jsr put_sprite ; 6
;=========
; 17 + 2190
;====================
; Handle keypresses
; if no keypress, 9
; if keypress, 6+43 = 49
lda KEYPRESS ; 4
bmi keypress
; 2
no_keypress:
; kill 40 cycles
ldx #0 ; 2
inc YPOS,X ; 6
inc YPOS,X ; 6
inc YPOS,X ; 6
inc YPOS,X ; 6
inc YPOS,X ; 6
inc YPOS,X ; 6
nop ; 2
jmp display_loop ; 3
;===================================================
; key was pressed handling takes 12 + 20 + 11 = 43
keypress:
; 1
bit KEYRESET ; 4
inc BIRD_STATE ; 5
and #$5f ; mask keypress ; 2
is_it_right:
cmp #$15 ; right arrow ; 2
bne is_it_left
; 2
inc XPOS ; 5
lda #0 ; 2
sta BIRD_DIR ; 3
lda YPOS ; 3-cycle nop ; 3
convoluted:
jmp adjust_xpos ; 3 ; 20 if right
is_it_left:
; 5
cmp #$8 ; left arrow ; 2
beq is_left
; 2
nop ; 2
lda YPOS ; 3-cycle nop
jmp convoluted ; 3
; ------ 20 if neither
is_left:
; 3
dec XPOS ; 5 ; 20 if left
lda #1 ; 2
sta BIRD_DIR ; 3
adjust_xpos:
lda XPOS ; 3
and #$1f ; keep in 0-31 range ; 2
sta XPOS ; 3
jmp display_loop ; 3
.include "gr_hline.s"
.include "../asm_routines/gr_unrle.s"
.align $100
.include "../asm_routines/keypress.s"
.include "gr_copy.s"
.include "gr_unrolled_copy.s"
.align $100
.include "gr_putsprite.s"
.include "mockingboard.s"
.include "vapor_lock.s"
.include "delay_a.s"
.include "waterfall_page1.inc"
.include "waterfall_page2.inc"
.align $100
.include "tfv_sprites.inc"
.align $100
;=================================
; Display Even
;=================================
; we have 65 cycles per line
; the first 25 are in hblank
; we come in already 21 cycles into things
; so the first scanline is a loss (but that's OK)
; first scanline: 21+ 2 (from ldy) so need to kill 65-23 = 42
; second scanline, again kill so 65 killed
display_even:
even_first_four_lines:
; we do mockingboard here
; we have 222 cycles (65*4 = 260 - 38 = 222)
; 38
; come in with 38
; 222 - 100 = 122 to kill
; kill 122
ldx #10 ; 2
dummy_loop:
asl DUMMY ; 6
dex ; 2
bne dummy_loop ; 3
; -1 exit loop
; 11 left over
nop ;2
lda XPOS ; 3
lda XPOS ; 3
lda XPOS ; 3
; high = 5 + 12+ 3 = 20
; medium = 5 + 9 + 6 = 20
; low = 5 + 9 + 6 = 20
lda XPOS ; 3
; cmp OLD_XPOS ; 3
; beq skip_mb ;
; 2
; sta OLD_XPOS ; 3
cmp #23 ; 2
bmi check_medium
; 2
lda #35 ; 2
sec ; 2
sbc XPOS ; 3
sta YPOS ; (nop) ; 3
was_low:
jmp write_volume ; 3
check_medium:
; 3
nop ; 2
nop ; 2
cmp #12 ; 2
bmi was_low
was_medium:
; 2
lda #12 ; 2
nop ; 2
write_volume:
; write A/noise volume
sta MB_VALUE ; 3
ldx #8 ; 2
lda #$2 ; 2
jsr write_ay_both ; 6+65
;===============
; 78
skip_mb:
; setup loop for next section
ldy #4 ; 2
even_twinkle_stars:
twinkle_loop_even:
; page1 for 4 lines, 65 - 4 = 61 -2 = 59 - 25 = 34
; line 0
bit PAGE1 ; 4
lda #34 ; 2
jsr delay_a ; 25+34
; line 1
bit PAGE1 ; 4
lda #34 ; 2
jsr delay_a ; 25+34
; line 2
bit PAGE1 ; 4
lda #34 ; 2
jsr delay_a ; 25+34
; line 3
bit PAGE1 ; 4
lda #27 ; 2
jsr delay_a ; 25+27
; below: 7 if not zero
; 7 (including ldy later) if is zero
dey ; 2
beq twinkle_loop_even_done ; 3
;-1
jmp twinkle_loop_even ; 3
twinkle_loop_even_done:
ldy #31 ; 2
falls_loop_even:
; === line 0
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; delay 11
bit PAGE0 ; 4
lda YPOS ; 3
bit PAGE0 ; 4
; delay 19
nop ; 2
nop ; 2
asl DUMMY ; 6
asl DUMMY ; 6
lda YPOS ; 3
;=== line 1
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; delay 11
bit PAGE0 ; 4
lda YPOS ; 3
bit PAGE0 ; 4
; delay 19
nop ; 2
nop ; 2
asl DUMMY ; 6
asl DUMMY ; 6
lda YPOS ; 3
;=== line 2
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; delay 11
bit PAGE1 ; 4
lda YPOS ; 3
bit PAGE0 ; 4
; delay 19
nop ; 2
nop ; 2
asl DUMMY ; 6
asl DUMMY ; 6
lda YPOS ; 3
;== line 3
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; delay 11
bit PAGE1 ; 4
lda YPOS ; 3
bit PAGE0 ; 4 ; 46
; delay 21 - 7 from loop
nop ; 2
nop ; 2
asl DUMMY ; 6
nop ; 2 ; 58
dey ; 2
beq falls_loop_even_done ; 3
; -1
jmp falls_loop_even ; 3
falls_loop_even_done:
ldy #12 ; 2
ground_loop_even:
;==== line 0
bit PAGE0 ; 4
; delay 61
lda #34 ; 2
jsr delay_a ; 25+34
;==== line 1
bit PAGE1 ; 4
; delay 61
lda #34 ; 2
jsr delay_a ; 25+34
;==== line 2
bit PAGE0 ; 4
; delay 61
lda #34 ; 2
jsr delay_a ; 25+34
;=== line 3
bit PAGE1 ; 4
; delay 54
lda #27 ; 2
jsr delay_a ; 25+27
dey ; 2
beq ground_loop_even_done ; 3
; -1
jmp ground_loop_even ; 3
ground_loop_even_done:
nop ; 2
jmp display_loop_return ; 3
.align $100
;=================================
; Display Odd
;=================================
; we have 65 cycles per line
; the first 25 are in hblank
display_odd:
; first scanline: comes in with 38
odd_first_four_lines:
; line 0-3 = 65*4 = 260
; -38
; -2
; -2
; -25
;=========================
; 193
lda #193 ; 2
jsr delay_a ; 125
ldy #4 ; 2
odd_twinkle_stars:
twinkle_loop_odd:
; page1 for 4 lines, 65 - 4 = 61 -2 = 59 - 25 = 34
; line 0
bit PAGE1 ; 4
lda #34 ; 2
jsr delay_a ; 25+34
; line 1
bit PAGE1 ; 4
lda #34 ; 2
jsr delay_a ; 25+34
; line 2
bit PAGE1 ; 4
lda #34 ; 2
jsr delay_a ; 25+34
; line 3
bit PAGE1 ; 4
lda #27 ; 2
jsr delay_a ; 25+27
dey ; 2
beq twinkle_loop_odd_done ; 3
; -1
jmp twinkle_loop_odd ; 3
twinkle_loop_odd_done:
ldy #31 ; 2
falls_loop_odd:
;=== line 0
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; falls 11
bit PAGE1 ; 4
lda YPOS ; 3
bit PAGE0 ; 4
; delay 19
nop ; 2
nop ; 2
asl DUMMY ; 6
asl DUMMY ; 6
lda YPOS ; 3
;==== line 1
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; falls 8
bit PAGE0 ; 4
lda YPOS ; 3
bit PAGE0 ; 4
; delay 19
nop ; 2
nop ; 2
asl DUMMY ; 6
asl DUMMY ; 6
lda YPOS ; 3
;=== line 2
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; falls 8
bit PAGE0 ; 4
lda YPOS ; 3
bit PAGE0 ; 4
; delay 19
nop ; 2
nop ; 2
asl DUMMY ; 6
asl DUMMY ; 6
lda YPOS ; 3
;===line 4
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; falls 11
bit PAGE1 ; 4
lda YPOS ; 3
bit PAGE0 ; 4 ; 44
; end falls
; delay 21 - 7 from loop
nop ; 2
nop ; 2
asl DUMMY ; 6
nop ; 2 ; 58
dey ; 2
beq falls_loop_odd_done ; 3
;-1
jmp falls_loop_odd ; 3
falls_loop_odd_done:
; 3
ldy #12 ; 2
ground_loop_odd:
;=== line 0
bit PAGE1 ; 4
; delay 61
lda #34 ; 2
jsr delay_a ; 25+34
;=== line 1
bit PAGE0 ; 4
; delay 61
lda #34 ; 2
jsr delay_a ; 25+34
;==== line 2
bit PAGE1 ; 4
; delay 61
lda #34 ; 2
jsr delay_a ; 25+34
;==== line 3
bit PAGE0 ; 4
; delay 54
lda #27 ; 2
jsr delay_a ; 25+27
dey ; 2
beq ground_loop_odd_done ; 3
;-1
jmp ground_loop_odd ; 3
ground_loop_odd_done:
; 3
nop ; 2
jmp display_loop_return ; 3
rts ; 6
.align $100
;=================================
; Display 3
;=================================
; we have 65 cycles per line
; the first 25 are in hblank
; we come in already 21 cycles into things
; so the first scanline is a loss (but that's OK)
; first scanline: 21+ 2 (from ldy) so need to kill 65-23 = 42
; second scanline, again kill so 65 killed
display_three:
three_first_four_lines:
; we do mockingboard here
; we have 222 cycles (65*4 = 260 - 38 = 222)
; 38
; come in with 38
; 222 - 100 = 122 to kill
; kill 122
ldx #10 ; 2
dummy_loop2:
asl DUMMY ; 6
dex ; 2
bne dummy_loop2 ; 3
; -1 exit loop
; 11 left over
nop ;2
lda XPOS ; 3
lda XPOS ; 3
lda XPOS ; 3
; high = 5 + 12+ 3 = 20
; medium = 5 + 9 + 6 = 20
; low = 5 + 9 + 6 = 20
lda XPOS ; 3
; cmp OLD_XPOS ; 3
; beq skip_mb2 ;
; 2
; sta OLD_XPOS ; 3
cmp #23 ; 2
bmi check_medium2
; 2
lda #35 ; 2
sec ; 2
sbc XPOS ; 3
sta YPOS ; (nop) ; 3
was_low2:
jmp write_volume2 ; 3
check_medium2:
; 3
nop ; 2
nop ; 2
cmp #12 ; 2
bmi was_low2
was_medium2:
; 2
lda #12 ; 2
nop ; 2
write_volume2:
; write A/noise volume
sta MB_VALUE ; 3
ldx #8 ; 2
lda #$2 ; 2
jsr write_ay_both ; 6+65
;===============
; 78
skip_mb2:
; setup loop for next section
ldy #4 ; 2
three_twinkle_stars:
twinkle_loop_three:
; line 0
bit PAGE0 ; 4
lda #34 ; 2
jsr delay_a ; 25+34
; line 1
bit PAGE1 ; 4
lda #34 ; 2
jsr delay_a ; 25+34
; line 2
bit PAGE1 ; 4
lda #34 ; 2
jsr delay_a ; 25+34
; line 4
bit PAGE0 ; 4
lda #27 ; 2
jsr delay_a ; 25+27
dey ; 2
beq twinkle_loop_three_done ; 3
; -1
jmp twinkle_loop_three ; 3
twinkle_loop_three_done:
ldy #31 ; 2
falls_loop_three:
;=== line 0
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; delay 11
bit PAGE1 ; 4
lda YPOS ; 3
bit PAGE0 ; 4
; delay 19
nop ; 2
nop ; 2
asl DUMMY ; 6
asl DUMMY ; 6
lda YPOS ; 3
;=== line 1
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; delay 11
bit PAGE1 ; 4
lda YPOS ; 3
bit PAGE0 ; 4
; delay 19
nop
nop
asl DUMMY ; 6
asl DUMMY ; 6
lda YPOS ; 3
;=== line 2
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; delay 11
bit PAGE0 ; 4
lda YPOS ; 3
bit PAGE0 ; 4
; delay 19
nop ; 2
nop ; 2
asl DUMMY ; 6
asl DUMMY ; 6
lda YPOS ; 3
;=== line 4
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; delay 11
bit PAGE0 ; 4
lda YPOS ; 3
bit PAGE0 ; 4 ; 44
; delay 21 - 7 from loop
nop ; 2
nop ; 2
asl DUMMY ; 6
nop ; 2 ; 58
dey ; 2
beq falls_loop_three_done ; 3
; -1
jmp falls_loop_three ; 3
falls_loop_three_done:
ldy #12 ; 2
ground_loop_three:
;=== line 0
bit PAGE1 ; 4
; delay 61
lda #34 ; 2
jsr delay_a ; 25+34
;=== line 1
bit PAGE0 ; 4
; delay 61
lda #34 ; 2
jsr delay_a ; 25+34
;=== line 2
bit PAGE1 ; 4
; delay 61
lda #34 ; 2
jsr delay_a ; 25+34
;=== line 3
bit PAGE0 ; 4
; delay 54
lda #27 ; 2
jsr delay_a ; 25+27
dey ; 2
beq ground_loop_three_done ; 3
; -1
jmp ground_loop_three ; 3
ground_loop_three_done:
nop ; 2
jmp display_loop_return ; 3
.align $100
;=================================
; Display Four
;=================================
; we have 65 cycles per line
; the first 25 are in hblank
; we come in already 21 cycles into things
; so the first scanline is a loss (but that's OK)
display_four:
; first scanline comes in with 38
four_first_four_lines:
; line 0-3 = 65*4 = 260
; -38
; -2
; -2
; -25
;=========================
; 193
lda #193 ; 2
jsr delay_a ; 25+193
ldy #4 ; 2
four_twinkle_stars:
twinkle_loop_four:
;=== line 0
bit PAGE1 ; 4
lda #34 ; 2
jsr delay_a ; 25+34
;=== line 1
bit PAGE1 ; 4
lda #34 ; 2
jsr delay_a ; 25+34
;=== line 2
bit PAGE1 ; 4
lda #34 ; 2
jsr delay_a ; 25+34
;=== line 3
bit PAGE1 ; 4
lda #27 ; 2
jsr delay_a ; 25+27
dey ; 2
beq twinkle_loop_four_done ; 3
; -1
jmp twinkle_loop_four ; 3
twinkle_loop_four_done:
ldy #31 ; 2
falls_loop_four:
;=== line 0
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; delay 11
bit PAGE0 ; 4
lda YPOS ; 3
bit PAGE0 ; 4
; delay 19
nop ; 2
nop ; 2
asl DUMMY ; 6
asl DUMMY ; 6
lda YPOS ; 3
;=== line 1
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; delay 11
bit PAGE1 ; 4
lda YPOS ; 3
bit PAGE0 ; 4
; delay 19
nop ; 2
nop ; 2
asl DUMMY ; 6
asl DUMMY ; 6
lda YPOS ; 3
;=== line 2
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; delay 11
bit PAGE1 ; 4
lda YPOS ; 3
bit PAGE0 ; 4
; delay 19
nop ; 2
nop ; 2
asl DUMMY ; 6
asl DUMMY ; 6
lda YPOS ; 3
;=== line 3
bit PAGE0 ; 4
; delay 31
lda #4 ; 2
jsr delay_a ; 25+4
; delay 11
bit PAGE0 ; 4
lda YPOS ; 3
bit PAGE0 ; 4 ; 44
; delay 21 - 7 from loop
nop ; 2
nop ; 2
asl DUMMY ; 6
nop ; 2 ; 58
dey ; 2
beq falls_loop_four_done ; 3
; -1
jmp falls_loop_four ; 3
falls_loop_four_done:
ldy #12 ; 2
ground_loop_four:
;=== line 0
bit PAGE0 ; 4
; delay 61
lda #34 ; 2
jsr delay_a ; 25+34
;=== line 1
bit PAGE1 ; 4
; delay 61
lda #34 ; 2
jsr delay_a ; 25+34
;=== line 2
bit PAGE0 ; 4
; delay 61
lda #34 ; 2
jsr delay_a ; 25+34
;=== line 3
bit PAGE1 ; 4
; delay 54
lda #27 ; 2
jsr delay_a ; 25+27
dey ; 2
beq ground_loop_four_done ; 3
; -1
jmp ground_loop_four ; 3
ground_loop_four_done:
nop ; 2
jmp display_loop_return ; 3
Reference in New Issue View Git Blame Copy Permalink