On Wed, 2008-07-30 at 15:31 -0500, Eric Shattow wrote: > Correction: the Indigo IO is 2 in / 2 out; the Indigo DJ is 0 in, 4 > out > > Unless I am mistaken. > > I'm guessing that the F/OSS options are basically: > > Custom board design with PCI envy24 chipset => ALSA : JACK / ~2ms > IEEE1394 devices made by ECHO (AudioFire2/4) => FFADO : JACK / ~4ms > Cardbus devices made by ECHO (Indigo IO/DJ) => ALSA : JACK / ~4ms > USB devices (48kHz native rate) => ALSA : JACK / ~8ms
I am living this one at the moment, needing a 32 in/32 out solution on eurocards interfaced to PC104+... The Envy24 is both difficult to source in small quantities and difficult to run in multiple with accurate timing between the multiple chips BCLK and LRCLK which you really need if your backplane has a single set of these signals supporting this much IO. The current plan is to make the audio interface look like a PATA disk which just happens to have say 4 sectors each of an appropriate number of samples, the logic to support this should fit in a couple of GALs or similar, and the bandwidth (and DMA) is there, getting the IDE stack out of the way might be a good trick however. I am open to both sources of envy24s and ideas on how to get everything synchronous (The best I came up with was to clock everything from the superclock input and rig some logic so that under software control I can cause this to drop individual clock pulses to each chip, then bring all the LR and word clocks into a general purpose input and at start up spin in a tight loop tweaking these timings until everything is in sync, uggh)... Still better then trying to design a PCI bridge in a spartan or similar! Regards, Dan. _______________________________________________ Linux-audio-dev mailing list [email protected] http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
