Am 19.03.23 um 18:49 schrieb BALATON Zoltan:
On Sun, 12 Mar 2023, Volker Rümelin wrote:
Am 12.03.23 um 15:09 schrieb Rene Engel:
Tested with -audiodev coreaudio,id=audio0,out.buffer-count=1 to 12
1 is too slow the rest up to 12 has no effect
The sampling frequency of the via-ac97 driver is 48000 Hz under
AmigaOs4.1
Any other ideas?
In audio/audio_template.h in the AUD_open_ functions there is one
ldebug ("open %s, freq %d, nchannels %d, fmt %d\n",
name, as->freq, as->nchannels, as->fmt);
line. Please replace this line with
fprintf(stderr, "open %s, freq %d, nchannels %d, fmt %d\n",
name, as->freq, as->nchannels, as->fmt);
compile and start AmigaOS. Use the default out.buffer-count. I
would like to know the via-ac97 drivers idea of the sampling
frequency.
Not sure this helps but I get these with DEBUG enabled in qemu/audio
on Linux host with alsa set to 44100 Hz dmix rate with default
settings without any -audiodev options with AmigaOS guest.
With pegasos2:
audio: open via-ac97.out, freq 44100, nchannels 1, fmt
1##############] 100 %
audio: open via-ac97.out, freq 44100, nchannels 2, fmt 3
alsa: enabling voice
alsa: disabling voice
alsa: alsa_fini
or pegasos2 with ES1370:
audio: open via-ac97.out, freq 44100, nchannels 2, fmt 3
alsa: enabling voice
alsa: disabling voice
alsa: alsa_fini
this does not play as slow as with sam460ex below but maybe a bit
slow which seems to improve with try-poll=off so this may be because
of the alsa backend issue. It's a bit faster with sdl backend, not
sure if that's the right speed or too fast but at least the backend
seems to influence playback speed.
Hi,
I still don't understand how the playback speed can slow down without
changing the pitch.
With sam460ex and ES1370:
audio: open es1370.dac2, freq 44100, nchannels 1, fmt 0
audio: open es1370.adc, freq 44100, nchannels 1, fmt 0
audio: open es1370.dac2, freq 48662, nchannels 1, fmt 0
audio: open es1370.adc, freq 48662, nchannels 1, fmt 0
audio: open es1370.dac2, freq 48662, nchannels 2, fmt 3
alsa: enabling voice
alsa: disabling voice
alsa: alsa_fini
this plays definitely slow and the freq also seems to be off. I may
have different AmigaOS versions on pegasos2 and sam460ex but I they
seem to use the same driver as there were no updates to that part.
I'm not sure what the driver in AmigaOS looks like but it may be
similar to the AROS AHI SB128 one. I don't know if higher level
parts in AHI may try to measure something like you mentioned but at
least the card driver does not seem to do that.
I had a look at the AROS SB128 driver and the AHI Preferences code.
There is no code to measure the audio clock frequency. The frequency
selection of 48662Hz seems to be a AROS/AmigaOS bug. This log is from
a AROS x86 guest. I hear some faint static noise but the playback
speed is correct.
open pcspk, freq 32000, nchannels 1, fmt 0
open es1370.dac2, freq 44100, nchannels 1, fmt 0
open es1370.adc, freq 44100, nchannels 1, fmt 0
open es1370.dac2, freq 48662, nchannels 1, fmt 0
open es1370.adc, freq 48662, nchannels 1, fmt 0
open es1370.dac2, freq 48662, nchannels 2, fmt 3
open es1370.dac2, freq 44100, nchannels 2, fmt 3
open es1370.adc, freq 44100, nchannels 1, fmt 0
