[EMAIL PROTECTED] wrote: > > With kernel 2.6.12 + "[PATCH] ehci-hcd - fix page pointer allocation in > > itd_patch()"), using jackd in realtime mode at 44.1kHz with 64 > > frames/period and 4 periods/buffer, I get a stream of xruns of about > > 0.020 ms, several per second. > > In USB, one frame == 1 msec. Most EHCI silicon using the 2.6.12 code > will get unhappy with 256 msec per ISO URB, so I hope you're using > "frame" without a necessary adjective ... ;) > ... > I discourage drivers from using more than 64 msec per ISO URB.
The URBs used by the snd-usb-audio driver are mostly independent of ALSA's period size, and use between 1 and 20 ms. > Thanks for the status info ... it's seeming that ISO-OUT through > EHCI is probably usable now. ISO-IN is a different story. :) Recording on both Edirol UA-1000 and Audigy 2 NX seems to work, and frequency feedback for the async out endpoints, too. Regards, Clemens ------------------------------------------------------- SF.Net email is sponsored by: Discover Easy Linux Migration Strategies from IBM. Find simple to follow Roadmaps, straightforward articles, informative Webcasts and more! Get everything you need to get up to speed, fast. http://ads.osdn.com/?ad_id=7477&alloc_id=16492&op=click _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
