mirror of
https://github.com/irmen/prog8.git
synced 2024-12-29 04:29:19 +00:00
257 lines
8.0 KiB
Lua
257 lines
8.0 KiB
Lua
%import textio
|
|
%import diskio
|
|
%import floats
|
|
%import adpcm
|
|
%import wavfile
|
|
%option no_sysinit
|
|
|
|
;
|
|
; This program can stream a regular .wav file from the sdcard.
|
|
; It can be uncompressed or IMA-adpcm compressed (factor 4 lossy compression).
|
|
; See the "adpcm" module source for tips how to create those files.
|
|
;
|
|
; Note that 8 bit wav files are *unsigned* values whereas Vera wants *signed* values
|
|
; so these have to be converted on the fly. 16 bit wav files are signed already.
|
|
;
|
|
; The playback is done via AFLOW irq handler that fills the audio fifo buffer
|
|
; with around 1 Kb of new audio data. (copies raw pcm data or decodes adpcm block)
|
|
; In the meantime the main program loop reads new data blocks from the wav file
|
|
; as it is being played.
|
|
;
|
|
; NOTE: stripping the wav header and just having the raw pcm data in the file
|
|
; is slightly more efficient because the data blocks are then sector-aligned on the disk
|
|
;
|
|
|
|
main {
|
|
uword vera_rate_hz
|
|
ubyte vera_rate
|
|
|
|
sub start() {
|
|
uword buffer = memory("buffer", 1024, 256)
|
|
str MUSIC_FILENAME = "?"*32
|
|
|
|
txt.print("name of .wav file to play on drive 8: ")
|
|
while 0==txt.input_chars(MUSIC_FILENAME) {
|
|
; until user types a name...
|
|
}
|
|
|
|
bool wav_ok = false
|
|
txt.print("\nchecking ")
|
|
txt.print(MUSIC_FILENAME)
|
|
txt.nl()
|
|
if diskio.f_open(MUSIC_FILENAME) {
|
|
void diskio.f_read(buffer, 128)
|
|
wav_ok = wavfile.parse_header(buffer)
|
|
diskio.f_close()
|
|
}
|
|
if not wav_ok {
|
|
error("no good wav file!")
|
|
}
|
|
|
|
calculate_vera_rate()
|
|
txt.print("wav format: ")
|
|
txt.print_ub(wavfile.wavefmt)
|
|
txt.print("\nchannels: ")
|
|
txt.print_ub(wavfile.nchannels)
|
|
txt.print("\nsample rate: ")
|
|
txt.print_uw(wavfile.sample_rate)
|
|
txt.print("\nbits per sample: ")
|
|
txt.print_uw(wavfile.bits_per_sample)
|
|
txt.print("\ndata size: ")
|
|
txt.print_uwhex(wavfile.data_size_hi, true)
|
|
txt.print_uwhex(wavfile.data_size_lo, false)
|
|
txt.print("\nvera rate: ")
|
|
txt.print_ub(vera_rate)
|
|
txt.print(" = ")
|
|
txt.print_uw(vera_rate_hz)
|
|
txt.print(" hz\n")
|
|
if wavfile.wavefmt==wavfile.WAVE_FORMAT_DVI_ADPCM {
|
|
txt.print("adpcm block size: ")
|
|
txt.print_uw(wavfile.block_align)
|
|
txt.nl()
|
|
}
|
|
|
|
if wavfile.nchannels>2 or
|
|
(wavfile.wavefmt!=wavfile.WAVE_FORMAT_DVI_ADPCM and wavfile.wavefmt!=wavfile.WAVE_FORMAT_PCM) or
|
|
wavfile.sample_rate > 48828 or
|
|
wavfile.bits_per_sample>16 {
|
|
error("unsupported format!")
|
|
}
|
|
|
|
if wavfile.wavefmt==wavfile.WAVE_FORMAT_DVI_ADPCM {
|
|
if(wavfile.block_align!=256 or wavfile.nchannels!=1) {
|
|
error("unsupported format!")
|
|
}
|
|
}
|
|
|
|
txt.print("\ngood file! playback starts!\n")
|
|
cx16.rombank(0) ; activate kernal bank for faster calls
|
|
cx16.VERA_AUDIO_RATE = 0 ; halt playback
|
|
cx16.VERA_AUDIO_CTRL = %10101111 ; mono 16 bit
|
|
if wavfile.nchannels==2
|
|
cx16.VERA_AUDIO_CTRL = %10111111 ; stereo 16 bit
|
|
if(wavfile.bits_per_sample==8)
|
|
cx16.VERA_AUDIO_CTRL &= %11011111 ; set to 8 bit instead
|
|
repeat 1024
|
|
cx16.VERA_AUDIO_DATA = 0 ; fill buffer with short silence
|
|
|
|
sys.set_irqd()
|
|
cx16.CINV = &interrupt.handler
|
|
cx16.VERA_IEN = %00001000 ; enable AFLOW only for now
|
|
sys.clear_irqd()
|
|
|
|
if diskio.f_open(MUSIC_FILENAME) {
|
|
uword block_size = 1024
|
|
if wavfile.wavefmt==wavfile.WAVE_FORMAT_DVI_ADPCM
|
|
block_size = wavfile.block_align
|
|
void diskio.f_read(buffer, wavfile.data_offset) ; skip to actual sample data start
|
|
void diskio.f_read(buffer, block_size) ; preload buffer
|
|
cx16.VERA_AUDIO_RATE = vera_rate ; start playback
|
|
repeat {
|
|
interrupt.wait_and_clear_aflow_semaphore()
|
|
;; cx16.vpoke(1,$fa00, $a0) ; paint a screen color
|
|
uword size = diskio.f_read(buffer, block_size)
|
|
;; cx16.vpoke(1,$fa00, $00) ; paint a screen color
|
|
if size<block_size
|
|
break
|
|
txt.chrout('.')
|
|
}
|
|
diskio.f_close()
|
|
} else {
|
|
txt.print("load error")
|
|
}
|
|
|
|
cx16.VERA_AUDIO_RATE = 0 ; halt playback
|
|
txt.print("done!\n")
|
|
repeat {
|
|
}
|
|
}
|
|
|
|
sub calculate_vera_rate() {
|
|
const float vera_freq_factor = 25e6 / 65536.0
|
|
vera_rate = (wavfile.sample_rate as float / vera_freq_factor) + 1.0 as ubyte
|
|
vera_rate_hz = (vera_rate as float) * vera_freq_factor as uword
|
|
}
|
|
|
|
sub error(str msg) {
|
|
txt.print(msg)
|
|
repeat {
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
interrupt {
|
|
|
|
bool aflow_semaphore
|
|
|
|
asmsub wait_and_clear_aflow_semaphore() {
|
|
%asm {{
|
|
- wai
|
|
lda p8_aflow_semaphore
|
|
bne -
|
|
inc p8_aflow_semaphore
|
|
rts
|
|
}}
|
|
}
|
|
|
|
sub handler() {
|
|
if cx16.VERA_ISR & %00001000 {
|
|
; AFLOW irq occurred, refill buffer
|
|
aflow_semaphore = 0
|
|
if wavfile.wavefmt==wavfile.WAVE_FORMAT_DVI_ADPCM
|
|
adpcm_block()
|
|
else if wavfile.bits_per_sample==16
|
|
uncompressed_block_16()
|
|
else
|
|
uncompressed_block_8()
|
|
} else if cx16.VERA_ISR & %00000001 {
|
|
cx16.VERA_ISR = %00000001
|
|
; handle vsync irq here
|
|
}
|
|
|
|
%asm {{
|
|
ply
|
|
plx
|
|
pla
|
|
rti
|
|
}}
|
|
}
|
|
|
|
asmsub uncompressed_block_8() {
|
|
; optimized loop to put 1024 bytes of data into the fifo as fast as possible
|
|
; converting unsigned wav 8 bit samples to signed 8 bit on the fly
|
|
%asm {{
|
|
lda p8_main.p8_start.p8_buffer
|
|
sta cx16.r0L
|
|
lda p8_main.p8_start.p8_buffer+1
|
|
sta cx16.r0H
|
|
ldx #4
|
|
- ldy #0
|
|
- lda (cx16.r0),y
|
|
eor #$80 ; convert to signed 8-bit
|
|
sta cx16.VERA_AUDIO_DATA
|
|
iny
|
|
bne -
|
|
inc cx16.r0H
|
|
dex
|
|
bne --
|
|
rts
|
|
}}
|
|
|
|
; original prog8 code:
|
|
; uword @requirezp ptr = main.start.buffer
|
|
; ubyte @requirezp sample
|
|
; repeat 1024 {
|
|
; sample = @(ptr) - 128
|
|
; cx16.VERA_AUDIO_DATA = sample
|
|
; ptr++
|
|
; }
|
|
}
|
|
|
|
asmsub uncompressed_block_16() {
|
|
; optimized loop to put 1024 bytes of data into the fifo as fast as possible
|
|
%asm {{
|
|
lda p8_main.p8_start.p8_buffer
|
|
sta cx16.r0L
|
|
lda p8_main.p8_start.p8_buffer+1
|
|
sta cx16.r0H
|
|
ldx #4
|
|
- ldy #0
|
|
- lda (cx16.r0),y
|
|
sta cx16.VERA_AUDIO_DATA
|
|
iny
|
|
bne -
|
|
inc cx16.r0H
|
|
dex
|
|
bne --
|
|
rts
|
|
}}
|
|
; original prog8 code:
|
|
; uword @requirezp ptr = main.start.buffer
|
|
; repeat 1024 {
|
|
; cx16.VERA_AUDIO_DATA = @(ptr)
|
|
; ptr++
|
|
; }
|
|
}
|
|
|
|
sub adpcm_block() {
|
|
; refill the fifo buffer with one decoded adpcm block (1010 bytes of pcm data)
|
|
uword @requirezp nibblesptr = main.start.buffer
|
|
adpcm.init(peekw(nibblesptr), @(nibblesptr+2))
|
|
cx16.VERA_AUDIO_DATA = lsb(adpcm.predict)
|
|
cx16.VERA_AUDIO_DATA = msb(adpcm.predict)
|
|
nibblesptr += 4
|
|
repeat 252 {
|
|
ubyte @zp nibble = @(nibblesptr)
|
|
adpcm.decode_nibble(nibble & 15) ; first word
|
|
cx16.VERA_AUDIO_DATA = lsb(adpcm.predict)
|
|
cx16.VERA_AUDIO_DATA = msb(adpcm.predict)
|
|
adpcm.decode_nibble(nibble>>4) ; second word
|
|
cx16.VERA_AUDIO_DATA = lsb(adpcm.predict)
|
|
cx16.VERA_AUDIO_DATA = msb(adpcm.predict)
|
|
nibblesptr++
|
|
}
|
|
}
|
|
}
|