emailler/client/examples/sidplay.s

230 lines
3.4 KiB
ArmAsm

.include "../inc/common.i"
.include "../inc/commonprint.i"
.import cfg_get_configuration_ptr
.import copymem
.importzp copy_src
.importzp copy_dest
.import ascii_to_native
.zeropage
.segment "STARTUP" ;this is what gets put at the start of the file on the C64
.word basicstub ; load address
basicstub:
.word @nextline
.word 2003
.byte $9e
.byte <(((init / 1000) .mod 10) + $30)
.byte <(((init / 100 ) .mod 10) + $30)
.byte <(((init / 10 ) .mod 10) + $30)
.byte <(((init ) .mod 10) + $30)
.byte 0
@nextline:
.word 0
init:
lda #14
jsr print_a
ldax #included_sid_length
stax sidfile_length
ldax #sid_data
jsr load_sid
bcc @ok
ldax #error
jmp print
@ok:
lda default_song
jsr init_song
jsr install_irq_handler
@loop:
jmp @loop
rts
load_sid:
stax sidfile_address
stax copy_src
ldy #1
lda (copy_src),y
cmp #'S' ;make sure the file starts with 'PSID' or 'RSID'
beq @ok
sec
rts
@ok:
ldy #7
lda (copy_src),y
sta header_length
inc header_length
inc header_length
tay
;y now points to the start of the real c64 file
lda (copy_src),y
sta copy_dest
iny
lda (copy_src),y
sta copy_dest+1
ldy #$0a
lda (copy_src),y
sta init_song+2
iny
lda (copy_src),y
sta init_song+1
iny
lda (copy_src),y
sta play_song+2
iny
lda (copy_src),y
sta play_song+1
ldy #$0f
lda (copy_src),y
sta number_of_songs
ldy #$11
lda (copy_src),y
sta default_song
ldy #$16
jsr print_ascii_string
ldy #$36
jsr print_ascii_string
ldy #$56
jsr print_ascii_string
ldax #songs
jsr print
lda number_of_songs
jsr print_hex
jsr print_cr
ldax #init_address
jsr print
lda init_song+2
jsr print_hex
lda init_song+1
jsr print_hex
jsr print_cr
ldax #play_address
jsr print
lda play_song+2
jsr print_hex
lda play_song+1
jsr print_hex
jsr print_cr
ldax sidfile_address
stax copy_src
clc
lda sidfile_address
adc header_length
pha
lda sidfile_address+1
adc #0
tax
pla
stax copy_src
sec
lda sidfile_length
sbc header_length
pha
lda sidfile_length+1
sbc #0
tax
pla
jsr copymem
clc
rts
install_irq_handler:
ldax $314 ;previous IRQ handler
stax jmp_old_irq+1
sei ;don't want any interrupts while we fiddle with the vector
ldax #irq_handler
stax $314 ;previous IRQ handler
sta irq_handler_installed_flag
cli
rts
irq_handler:
lda $d012
cmp #100
bne irq_handler
lda $01
pha
lda #$35
sta $01
inc $d020
jsr play_song
dec $d020
pla
sta $01
jmp jmp_old_irq
print_ascii_string:
:
lda (copy_src),y
beq :+
jsr ascii_to_native
jsr print_a
iny
bne :-
:
jmp print_cr
.bss
number_of_songs: .res 1
default_song: .res 1
sidfile_address: .res 2
header_length: .res 1
sidfile_length: .res 2
.rodata
songs:
.byte "SONGS $",0
error:
.byte "ERROR",13,0
init_address:
.byte "LOAD ADDRESS $",0
play_address:
.byte "PLAY ADDRESS $",0
sid_data:
;.incbin "Melonix.sid"
; .incbin "Power_Train.sid"
; .incbin "Y-Out.sid"
.incbin "outlaw.sid"
included_sid_length=*-sid_data
.data
irq_handler_installed_flag: .byte 0
init_song:
jmp $ffff
play_song:
jmp $ffff
jmp_old_irq:
jmp $ffff