Hail,
I am introducing myself to SDR technology and gnuradio through
whatever project documentation I find, dissecting the code and executing
simple experimental flow graphs to test understanding of concepts,
hoping to avoid forum queries (this is my first). Although the audio
sink is not critical to my ultimate use of gnuradio and a bit of a
diversion I will eventually start digging into it. However, I thought to
submit a query on whether there is something obvious I should try in
order to get it working. I am using gnu radio companion 3.8.1.0 (Python
3.6.10) and feeding the audio sink with a 1 kHz tone from the signal
source block.
(1) staring with:
:~> aplay -L
null
Discard all samples (playback) or generate zero samples (capture)
default
Default ALSA Output (currently PulseAudio Sound Server)
sysdefault:CARD=PCH
HDA Intel PCH, ALC892 Analog
Default Audio Device
front:CARD=PCH,DEV=0
HDA Intel PCH, ALC892 Analog
Front speakers
surround21:CARD=PCH,DEV=0
HDA Intel PCH, ALC892 Analog
2.1 Surround output to Front and Subwoofer speakers
(...)
hdmi:CARD=PCH,DEV=0
HDA Intel PCH, HDMI 0
HDMI Audio Output
hdmi:CARD=PCH,DEV=1
HDA Intel PCH, HDMI 1
HDMI Audio Output
hdmi:CARD=PCH,DEV=2
HDA Intel PCH, HDMI 2
HDMI Audio Output
hdmi:CARD=PCH,DEV=3
HDA Intel PCH, HDMI 3
HDMI Audio Output
hdmi:CARD=PCH,DEV=4
HDA Intel PCH, HDMI 4
HDMI Audio Output
(2) using sysdefault:CARD=PCH for the audio sink device name,
both 44.1 kS/s and 48 kS/s the following runtime error results:
(3)
gr::log :INFO: audio source - Audio sink arch: oss
audio_oss_sink: sysdefault:CARD=PCH: No such file or directory
Traceback (most recent call last):
File "/gnuradio/examples/audiotest.py", line 136, in <module>
main()
File "/gnuradio/examples/audiotest.py", line 112, in main
tb = top_block_cls()
File "/gnuradio/examples/audiotest.py", line 78, in __init__
self.audio_sink_0 = audio.sink(samp_rate, 'sysdefault:CARD=PCH', True)
File
"/usr/local/lib64/python3.6/site-packages/gnuradio/audio/audio_swig.py",
line 220, in make
return _audio_swig.sink_make(*args, **kwargs)
RuntimeError: audio_oss_sink
>>> Done (return code 1)
(4) Fixing this isn't critical and in time I will get to the bottom of
it; the forum query just removes the possibility of an obvious answer
that most everyone else knows about. My guess is that I have to disable
the Pulse audio server.
Rick