From: Dien Nguyen <[email protected]> Reply-To: "[email protected]" <[email protected]> Date: Sunday, November 30, 2014 at 9:37 PM To: "[email protected]" <[email protected]> Subject: Re: [beagleboard] Audio capture issue with BeagleBone Black and Audio Cape Rev B
> Hi John, > > Did you solve the issue yet, may you please share how to fix it? We also tried > with 3.18 and the issue is still there. I never really looked into the issue because it wasn¹t important to me. As long as I could record and playback on the BBB, I was OK, but I did notice the issue when I recorded on the BBB and then played back on my Ubuntu desktop. I looked at the schematics and I see that GPIO3_21 (AUD_MCLK) is driven by either Y4 (24.576MHz) or MCASP0_AHCLKX. So I did a few measurements and AUD_MCLK is always 24MHz no matter what the sampling rate. In the DTS the codec-clock-rate is shown as 12000000 so this doesn¹t make any sense. Perhaps the MCASP code isn¹t reading this number correctly and is defaulting to 24MHz. Regards, John > > Thanks, > Dustin > > On Mon, Dec 1, 2014 at 12:29 PM, John Syn <[email protected]> wrote: >> >> From: Dien Nguyen <[email protected]> >> Reply-To: "[email protected]" <[email protected]> >> Date: Sunday, November 30, 2014 at 7:14 PM >> To: "[email protected]" <[email protected]> >> Subject: [beagleboard] Audio capture issue with BeagleBone Black and Audio >> Cape Rev B >> >>> >>> Hi All, >>> >>> We tried the Audio Cape Rev B with BeagleBone Black. The kernel version is >>> 3.14.17 (https://github.com/RobertCNelson/bb-kernel.git branch am33x-v3.14) >>> >>> We was able to play and record via the Audio Cape. If we record and play the >>> file via the Audio Cape, it works fine. But when we move the recorded file >>> to other machine or play it via the USB Sound Card, the speed of the >>> recorded file seems 1.5 time slower than it really is. >>> >>> On the board, we recorded the audio with >>> arecord -t raw -f S16_LE -r 44100 /tmp/1.raw >>> >>> Then, we playback the file with command >>> aplay -t raw -f S16_LE -r 44100 /tmp/1.raw >>> >>> 1/ On x86 machine, the voice become very slow. If we change the sampling >>> rate to 63000, it is played close to the real voice we recorded. >>> 2/ Trying with a USB Sound Card plugged directly to the board. >>> aplay -t raw -f S16_LE -r 44100 -D plughw:1,0 /tmp/1.raw >>> We saw the same issue as seen on x86 machine >>> >>> It seems that there is something wrong with the sampling rate clock. May >>> anyone please give some suggestions >> I¹ve seen the same problem when recording on the BBB and then playing the >> same file on my Ubuntu Desktop. Not sure why this happens. I¹m using >> 3.15.10-bone8. >> >> Regards, >> John >>> >>> Thanks >>> -- >>> For more options, visit http://beagleboard.org/discuss >>> --- >>> You received this message because you are subscribed to the Google Groups >>> "BeagleBoard" group. >>> To unsubscribe from this group and stop receiving emails from it, send an >>> email to [email protected]. >>> For more options, visit https://groups.google.com/d/optout. >> -- >> For more options, visit http://beagleboard.org/discuss >> --- >> You received this message because you are subscribed to a topic in the Google >> Groups "BeagleBoard" group. >> To unsubscribe from this topic, visit >> https://groups.google.com/d/topic/beagleboard/XmMg5DjJvsk/unsubscribe. >> To unsubscribe from this group and all its topics, send an email to >> [email protected]. >> For more options, visit https://groups.google.com/d/optout. > > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
