mirror of https://github.com/a2-4am/4cade.git
69 lines
1.4 KiB
Plaintext
69 lines
1.4 KiB
Plaintext
;license:MIT
|
|
;(c) 2021 by Frank M.
|
|
|
|
!cpu 6502
|
|
!to "res/DEMO/GALAXIAN",plain
|
|
*=$300
|
|
|
|
!source "src/constants.a" ; no code in these
|
|
!source "src/macros.a"
|
|
|
|
+READ_RAM2_WRITE_RAM2
|
|
jsr EnableAccelerator
|
|
+LOAD_FILE_AT title, $00
|
|
|
|
lda #$60
|
|
sta $5813
|
|
jsr $5800 ; decompress
|
|
|
|
ldx #0
|
|
stx $83F
|
|
inx
|
|
stx $847 ; reset vector fix
|
|
|
|
lda #$2C
|
|
sta $1909
|
|
sta $190C ; ignore joystick buttons
|
|
|
|
ldx #5-1
|
|
- lda patch1, x
|
|
sta $8E5, x
|
|
dex
|
|
bpl - ; exit on keypress during title screen
|
|
|
|
ldx #5-1
|
|
- lda patch2, x
|
|
sta $E50, x
|
|
dex
|
|
bpl - ; exit on keypress during demo
|
|
|
|
lda #<callback
|
|
sta $8FF+1
|
|
lda #>callback
|
|
sta $8FF+2 ; set exit at end of demo cycle
|
|
|
|
+DISABLE_ACCEL
|
|
jmp $800
|
|
|
|
callback dec count
|
|
bne +
|
|
lda #0
|
|
sta $8FF+1
|
|
lda #1
|
|
sta $8FF+2 ; exit after 3 times
|
|
+ jmp $A00
|
|
|
|
count !byte $03
|
|
|
|
patch1 !byte $10,$05,$4C,$00,$01
|
|
|
|
patch2 !byte $10,$49,$4C,$00,$01
|
|
|
|
title !byte x_e-x_b
|
|
x_b !text "X/GALAXIAN/GALAXIAN"
|
|
x_e
|
|
|
|
!if * > $3F0 {
|
|
!error "code is too large, ends at ", *
|
|
}
|