[LAU] HDSP 9632 - Just pcm0p !?

Giso Grimm gg3137 at vegri.net
Mon Oct 26 10:23:31 EDT 2009


Hi Klaus,

the ALSA hardware device is just a single 18 channel (or whatever number
of channels you have) device. The ALSA plughw-device does some mapping,
which allows playback of different channel count on your multichannel
card. The signal routing can be controlled in the ALSA settings (see
'route_policy').

To simultaneously access the single device with different applications
you should define a 'dmix' software device. I am not an expert on dmix
settings, it is described on

http://www.alsa-project.org/main/index.php/Asoundrc

However, I did not find a documentation on how to setup multiple stereo
devices with different output channels.

All this is no problem at all with jack, simply connect any client to
the channels you want (or route from client to client). Most
applications support jack, so it should not be a problem. No GUI is
needed (for headless setups).

--
Giso


Klaus Schulz wrote:
> Hi folks.
> 
> On my quest to get  more then two channels from Alsa out to the 9632
> I stepped over this:
> 
> I figured that there is just a  pcm0p  under /proc/asound/card0.
> 
> Shouldn't there be pcm0p...pcm7p reflecting the 8 Alsa stereo channels
> on the HDSP?
> 
> What am I mixing up here?




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