prog8/examples/cx16/zsound/stream-test-zcm.p8
Irmen de Jong 08ac459a41 breaking change: sys.set_irq() and sys.set_rasterirq() no longer have useKernal parameter! The irq handler routine must return a boolean instead in the A register.
When it returns true it means run the system IRQ handler afterwards. When it returns false, the system handler is NOT ran afterwards.
2023-11-21 23:22:53 +01:00

87 lines
2.8 KiB
Lua

%import textio
%import diskio
%zpreserved $22,$2d ; zsound lib uses this region
; NOTE: this is a proof of concept to stream ZCM digi from disk while playing.
; currently there's no real streaming API / circular buffer in zsound,
; so it simply loads the whole ZCM file in chunks in memory sequentially.
; But it does so while the playback is going on in the background.
; It seems fast enough to stream + play 16khz 16bit stereo samples. (around 64 Kb/sec)
; Maybe we can go faster but 22 Khz seemed too much to keep up with.
main $0830 {
zsound_lib:
; this has to be the first statement to make sure it loads at the specified module address $0830
%asmbinary "zsound_combo-0830.bin"
; note: jump table is offset by 2 from the load address (because of prg header)
romsub $0832 = zsm_init() clobbers(A)
romsub $0835 = zsm_play() clobbers(A, X, Y)
romsub $0838 = zsm_playIRQ() clobbers(A, X, Y)
romsub $083b = zsm_start(ubyte bank @A, uword song_address @XY) clobbers(A, X, Y) -> bool @Pc
romsub $083e = zsm_stop()
romsub $0841 = zsm_setspeed(uword hz @XY) clobbers(A, X, Y)
romsub $0844 = zsm_setloop(ubyte count @A)
romsub $0847 = zsm_forceloop(ubyte count @A)
romsub $084a = zsm_noloop()
romsub $084d = zsm_setcallback(uword address @XY)
romsub $0850 = zsm_clearcallback() clobbers(A)
romsub $0853 = zsm_get_music_speed() clobbers(A) -> uword @XY
romsub $0856 = pcm_init() clobbers(A)
romsub $0859 = pcm_trigger_digi(ubyte bank @A, uword song_address @XY)
romsub $085c = pcm_play() clobbers(A, X, Y)
romsub $085f = pcm_stop() clobbers(A)
romsub $0862 = pcm_set_volume(ubyte volume @A)
const ubyte digi_bank = 1
const uword digi_address = $a000
const ubyte zcm_DIGITAB_size = 8 ; header size
const uword ram_bank_size = $2000
ubyte load_ok = false
sub prebuffer() {
txt.print("prebuffering...")
void diskio.f_read(digi_address, ram_bank_size*4)
}
sub start() {
txt.print("\nzsound digi streaming (drive 8)!\n")
if not diskio.f_open("thriller.zcm") {
txt.print("?no file\n")
return
}
cx16.rambank(digi_bank)
prebuffer()
pcm_init()
pcm_trigger_digi(digi_bank, digi_address)
sys.set_irq(&zsm_playroutine_irq)
txt.print("\nstreaming from file, playback in irq!\n")
uword size = 1
while size {
size = diskio.f_read(digi_address, ram_bank_size) ; load next bank
txt.print_ub(cx16.getrambank())
txt.spc()
sys.wait(5) ; artificial delay
}
txt.print("sound file end reached.\n")
diskio.f_close()
repeat {
}
pcm_stop() ;unreached
}
sub zsm_playroutine_irq() -> bool {
pcm_play()
return true
}
}