[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Discuss-gnuradio] audio_alsa: problem with "valve" at head of audio

From: Alexandru Csete
Subject: Re: [Discuss-gnuradio] audio_alsa: problem with "valve" at head of audio_alsa sink sub-graph
Date: Fri, 5 Nov 2010 13:55:45 +0100

On Mon, Oct 25, 2010 at 7:43 PM, Marcus D. Leech <address@hidden> wrote:
On 10/25/2010 11:25 AM, Almohanad Fayez wrote:
Marcus, this is a problem with the gnuradio/gr-audio-alsa/src/audio_alsa_source.cc.  I ran into a few weeks ago and i managed to find a quick and dirty fix for.  

I'm assuming that you're stopping the flow graph and restarting it again. if you look into the "check_topology" method.  There's a FIXME there, what I beleieve is happening, is that when you try to restart the flowgraph after stopping it GNU Radio is trying to reset  your sound card and it thinks that it's in a corrupt state. 

My fix was to add a "static bool" variable that skips the "snd_pcm_hw_params(d_pcm_handle, d_hw_params);" function call.  the flag is "static" just so you can detect your first entry.  After that run make and make install and things should work fine.


I'm not actually stopping/restarting the flow-graph.  I'm simply opening a 'valve' block that's
  at the head of the sub-graph that feeds the audio sink.   I'll look at the "check_topology'
  method as you suggest, though.

This happens as soon as I "open" (stop data flow) the valve block.

I have also started to encounter this problem, both when using a Selector block in GRC or when performing lock/reconfigure/unlock in python code. The trick with the static bool conditional works well for me. Thanks for the tip.


reply via email to

[Prev in Thread] Current Thread [Next in Thread]