Hello all GnuRadio users,
I wanted to have a flowgraph without an USRP source and USRP sink, only
by using the software blocks. The objective is to transmit and receive
the BPSK modulated packets.
I attached a thread at the receiver to watch if the packets are
demodulated. When I run my flowgraph no packet has been received. After
that, to see if the packets have been decoded in my packet sink, I
changed a CC code by adding a fprintf function. When i launched the
python flow graph, I started to print a received packets.
Can you explain me why I have got this probleme ? Is it a packet queue
of my watcher in python or there are a specific problem ?
Thank you for your replay.
Hi Raf Raf,
I’m not quite sure this is what’s happening here, but:
Threading with python and GNU Radio can be a bit tricky, and even more
tricky when you use a GUI framework.
Maybe you should elaborate on what you mean with “I attached a thread”,
so we can understand your architecture better 
Greetings,
Marcus
Remove the printf. Put in “tag debug” blocks at different points in your
flowgraph to see what’s going on.