Le 8 oct. 08 à 06:40, Hannu Savolainen a écrit : > Yair K. wrote: >> On Tuesday 07 October 2008 21:05:41 Hannu Savolainen wrote: >> >>> Stéphane Letz wrote: >>> >>>> Hi, >>>> >>>> We are implementing a full duplex backend that is using separated >>>> in/ >>>> out devices. Basically we are following what is explained in the >>>> "Using separate input and output devices" section in the following >>>> page http://manuals.opensound.com/developer/full_duplex.html. We >>>> use a >>>> single thread that is doing read/write in a loop. >>>> >>>> Everything works as expected on a HDAudio card on Solaris à 48 kHz: >>>> read is the function that blocks and drive the audio timing. But >>>> when >>>> using another sample rate values (like 44.1 kHz) on the same card, >>>> then write is blocking and read returns immediately. >>>> >>>> >>> This is probably caused by the virtual mixer (vmix) subsystem that >>> uses >>> the device at fixed 48 kHz rate. Other rates will require >>> conversions >>> which make recording and playback to work in slightly different >>> way. You >>> can bypass vmix by opening the device with the O_EXCL flag. >>> >> >> Can SNDCTL_DSP_COOKEDMODE be used instead? >> http://manuals.opensound.com/developer/fulldup.c.html#LOC8 Seems to >> do this. >> > Actually this is necessary too (in addition to O_EXCL). > > Best regards, >
Ok. Now testing with O_EXCL and SNDCTL_DSP_COOKEDMODE works, bit I see some strange of the device. The overruns/underrun detection code based on SNDCTL_DSP_GETERROR does not see underrun anymore although the sound get weird with high CPU load (Writing another buffer in the out device solve the "weird sound" problem...). The same overruns/underrun detection code was working when opening the /dev/dsp0 device (that uses vmix AFAIK) This occurs on OpenSolaris with internal HDAudio using published OSS 4.0. Are tey know problems with this card with OSS 4.0 ? Best Regards Stephane Letz _______________________________________________ oss-devel mailing list oss-devel@mailman.opensound.com http://mailman.opensound.com/mailman/listinfo/oss-devel
