Re: [Discuss-gnuradio] Problem feeding garbage to GNU Radio

[Philip Balister]

On Sat, Oct 11, 2008 at 12:06 PM, Eric Blossom <address@hidden> wrote:
> On Fri, Oct 10, 2008 at 02:59:33PM -0400, Philip Balister wrote:
>> I'm working on a flow graph that reads samples from a file and feeds
>> them to the wfm demod block. I managed to get this working, but along
>> the way I ran across a problem ....
>>
>> My data file is 16bit complex shorts in big-endian format. It looks
>> like the file source block reads data from the file and sends it to
>> the fm demod which is expecting a complex float data. I attempted a
>> quick test by using the original data file (wrong format) which caused
>> the flow graph to crash with a seg fault. After converting the data to
>> a complex float representation the flowgraph works.
>>
>> Do people view this as a problem? It seems like the file source block
>> should attempt  some form of sanity checking on incoming data. If you
>> aren't expecting a problem, I could see this being hard for people new
>> to GNU Radio to debug.
>>
>> Philip
>
> It shouldn't segfault regardless of the input.
>
> Can you send or post a link to the flow graph and the test data that
> reproduces the problem?
>
> A gdb stack trace would let us know where it's blowing up.
> From there the bug should be easy to find and fix.

I've attached the flow graph.

The data file is here:

http://ossie.wireless.vt.edu/~balister/capture/npr_iq_sample.dat

Right now I'm working through figuring out how many python modules are
needed to run the flow graph, if I have a chance I'll try and get a
stack trace. I'm assuming you gsb python and run the flow graph? Arg,
how do I get the python interpreter to load and run top_block.py .....

Philip

top_block.py
Description: Text Data