2011/9/14 Clemens Ladisch clemens@ladisch.de:
Raymond Yau wrote:
Is 256 frames/period in s16 stereo since the card support mono , stereo , U8 and S16 ,
The hardware uses S16 stereo at 48 kHz internally; everything else is converted and resampled to that.
using ubuntu 11.04 Live CD
After select "Mono Duplex" profile in gnome sound preference , gnome speaker-test crash
What is the meaning of SNDRV_PCM_INFO_BLOCK_TRANSFER
That the card transfers samples in blocks.
since the rewind_safeguard of PA server is 256 bytes ?
A block in the native format has 1024 bytes.
Do you mean hardware pointer is only updated every 5.333ms ?
similar to usb audio using 5 urbs
and this is why the driver force the application to use 3 periods per buffer
help since minimum period time of snd_ymfpci is 5.333ms but alsa-pulse plugin announce a lower value 128 bytes (period_bytes_min) to the alsa application ?
Doesn't PA assume that the hardware has accurate pointer positions? Without this, smaller periods do not make sense unless PA can interpolate from the period interrupts.
PA server use the value from snd_pcm_available() to determine the sleep time , You have to ask PA developer whether PA can interpolate from the period interrupts
e.g. hda , emu10k1 and au88x0 use the values from hardware register as the playback position in pointer callback