[alsa-devel] USB asynchronous mode feedback format

Julian Scheel julian at jusst.de
Thu Oct 14 14:56:51 CEST 2010

Am Donnerstag, 14. Oktober 2010, 14:33:22 schrieb Daniel Mack:
> On Thu, Oct 14, 2010 at 02:30:43PM +0200, Julian Scheel wrote:
> > Am Donnerstag, 14. Oktober 2010, 14:06:41 schrieb Daniel Mack:
> > > Yes, that looks suspicious, especially because it doesn't only affect
> > > the lower bits. What do you need this sample rate converter for,
> > > anyway? Can't you feed your signals directly to the DAC? FMT0 and FMT1
> > > should both be set to 0.
> > 
> > You mean OFMT0 and OFMT1? Imho they should be 1,0 for I2S. Or did you
> > refer to the DAC? In that case FMT0 and FMT1 both are set to 0.
> Jup, I was talking about the DAC.

I have the SRC in there to be able to always feed that DAC with 192kHz, as it 
performs best in that mode and allows usage of a slow roll-off filter then.
Anyway, I tried to directly feed the DAC module as well, but it does not 
produce any output so far... Not sure what's wrong there.
As the dac is a current output dac, I am not sure whether it really does not 
output any signal, or if the current->voltage conversion does not work.


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