Re: [Discuss-gnuradio] Problem with std.ihx

[Martin Gawecki]

Thanks George,

Increasing the decimation did fix the oscope and fft problem, I got away with using 64 and not getting those "u0"s. Do you have any advice on the FM receiver - it doesn't seem like there's an option to change the decimation for that script, and I keep getting those "aU" strings (sorry, I thought they were "uA", but they're actually "aU"). I'm not sure if this is important, but I also get a message that says:

FYI: No Powermate or Contour Knob found

And by the way - is there someplace where I can just look up what all these erroneous outputs mean?

Thanks,
~Martin

On Nov 25, 2007 3:38 PM, George Nychis <address@hidden> wrote:

> On a somewhat related question, when I do run usrp_fft.py as well as
> usrp_oscope.py, I'm not able to actually control the GUI - it seems like
> its "frozen" although I do get some waveforms. At the same time, the
> string "u0" is continually written to the terminal.
>
> I was also trying to get the FM receiver to work and encountered a
> similar problem - I get "uA" in the terminal, the GUI is non-responsive,
> and the graphs look like they're only displaying in an alternating
> fashion (2-3 seconds for the "Data from USRP" and then a few seconds for
> the "Post Demod"). I'm just running the script with one option, -f
> freq1, and I can sort-of make out some semblance of music on the
> stations I try, but the signal is pretty noisy. I am using an external 3
> foot antenna, so I'm not really sure what the problem is...
>

It seems as though your host machine is not able to keep up.  The uO
refers to USRP overrun, your machine is not keeping up with the incoming
data and some of it is being dropped.  Given this behavior, you're
likely not getting a responsive GUI for the same reason.

As a start, try running the oscope with a higher decimation rate like 256:
usrp_oscope.py -d 256

See if you still get overruns, and if the GUI is responsive.

- George