From: Clemens L. <cl...@la...> - 2010-10-05 15:48:55
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Euan de Kock wrote: > Is the efc/fireworks stuff an implementation of the Echo proprietary > format in FFADO? Yes. > This unit is fully capable of working with this rate, and if I set the > rate from Windows it will persist, and then from Linux I can only set > the higher rates (88.2 and 96) but not the lower ones. (44.1, 48). > > Using nosy to look at the Windows traffic, this is what the Echo console > sends: (0x0BB80 = 48000, 0x17700 = 96000) > [00000009 00000001 0000239e 00000003 00000000 00000000 00000000 0000bb80 00000000] > [00000009 00000001 000023ba 00000003 00000000 00000000 00000000 00017700 00000000] Apparently, commands to this address doesn't use the FCP header (which would be just a vendor-specific AV/C command with vendor ID 000000). struct efc_header: 00000009 length (9 quadlets) 00000001 version 000023ba sequence number (increased for each command so that the command can be associated with its response) 00000003 category: CAT_HARDWARE_CONTROL 00000000 command: HWCTRL_SET_CLOCK 00000000 retval (set in responses) struct efc_clock: 00000000 clock: HW_CLOCK_INTERNAL 00017700 sample rate 00000000 index (?) > I thought SET_CLOCK referred to the clock source - Internal, SPDIF. ADAT > etc. Both clock source and sample rate. > So what path would you suggest I take ? > > Pursue a correct AV/C compliance with ECHO. AFAIK the AV/C commands are intended to be used by the built-in driver of OS X. > Get libffado to use the firecontrol/ ecc0 command set for samplerate > setting. Should be easiest. Regards, Clemens |