On Thu, 2009-05-21 at 22:43 -0700, Troy Kisky wrote: > Rajashekhara, Sudhakar wrote: > >> Rajashekhara, Sudhakar wrote: > >>> Troy, > >>> > >>> I tried this patch on DM644x EVM and following are my observations: > >>> > >>> 1. Playback works fine. > >>> 2. Record has some issues. Recorded stream has Loud volume on > >>> the right side, and on the left, volume is very low. > >>> 3. Loopback (arecord -f cd | aplay -f cd) has some issues. > >>> Audio is bit noisy here. I think if arecord issues are fixed, > >>> this may go away. > >>> > >>> On DM355, though arecord and aplay work fine independently. But > >>> once loopback is run, arecord records data only on one side. > >>> Loopback is noisy with intermittent overrun/underrun messages both > >>> on DM355 and DM644x EVMs. > >>> > >> Thanks for testing... Can you post the overrun/underrun messages. > > > > # arecord -f cd | aplay -f cd > > Recording WAVE 'stdin' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo > > Playing WAVE 'stdin' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo > > underrun!!! (at least 0.372 ms long) > > underrun!!! (at least 0.146 ms long) > > underrun!!! (at least 0.147 ms long) > > underrun!!! (at least 0.153 ms long) > > underrun!!! (at least 0.153 ms long) > > underrun!!! (at least 0.159 ms long) > > underrun!!! (at least 0.149 ms long) > > underrun!!! (at least 0.153 ms long) > > underrun!!! (at least 0.153 ms long) > > underrun!!! (at least 0.236 ms long) > > underrun!!! (at least 0.147 ms long) > > underrun!!! (at least 0.180 ms long) > > underrun!!! (at least 0.159 ms long) > > underrun!!! (at least 0.154 ms long) > > underrun!!! (at least 0.154 ms long) > > underrun!!! (at least 0.149 ms long) > > underrun!!! (at least 0.145 ms long) > > underrun!!! (at least 0.149 ms long) > > underrun!!! (at least 0.176 ms long) > > Aborted by signal Interrupt... > > Aborted by signal Interrupt... > > # > > > > After I stop it, if I re-run the same command as above, I am not > > getting these messages. > > > >> Which codec does the DM355 use. Is it AIC33 like DM6446 EVM? > >> > > > > Yes, DM355 is using AIC33. > > > > Regards, Sudhakar > > > > > > > > Hmm do you know if the aic33 is initialized at 44100, or is alsa arecord > converting the input > from 48000 to 44100 and then aplay converting the opposite direction.
There is a clock divide in AIC33 to support 44100 sample rate, so ALSA does not need to do any conversions. I'm curious if latency in record is causing playback underrun. Regards, Steve > > Troy > > > _______________________________________________ > Davinci-linux-open-source mailing list > [email protected] > http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source _______________________________________________ Davinci-linux-open-source mailing list [email protected] http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
