Hi everyone,

Firstly, just a disclaimer. I am  particularly familiar with GnuRadio at
all. However I need to interface with a GnuRadio project.

I am trying to manually decode the output of a ZMQ PUB Sink. In other
words, I have, in a completely different non-gnuradio project, a bit of
code that uses the standard python-zmq library to subscribe to the zmq
socket.


The ZMQ PUB Sink block is sitting just before the USRP block in the Tx
chain. And what I eventually want to do is effectively replicate the
spectrum display from Gnu Radio in a web app.


In my long google searches someone said the trick to decode things from
gnuradio is to use the PMT library. Now from what I could see I should use
pmt.deserialize_string(). However that does not seem to work.

>>> pmt.deserialize_str(d)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python2.7/dist-packages/pmt/pmt_swig.py", line 3373, in
deserialize_str
    return _pmt_swig.deserialize_str(str)
RuntimeError: pmt::deserialize: malformed input stream, tag value = : 243

I thought perhaps there would be an alignment issue, but it doesn't seem to
matter where (in d) I start the deserialize command.

By the way, d above is a recording of what I saw come out of that ZMQ PUB
Sink block. I created a python-zmq socket and connected it to the ZMQ Sink
Block port and recorded everything. You can find the file here:
https://www.dropbox.com/s/9r6390lwd3kdc9o/port_5551.bin?dl=1

Any pointers would be most appreciated. Thanks in advance.

Kjetil
_______________________________________________
Discuss-gnuradio mailing list
Discuss-gnuradio@gnu.org
https://lists.gnu.org/mailman/listinfo/discuss-gnuradio

Reply via email to