[Discuss-gnuradio] flow graph with feedback by using udp source/sink

[Alick Zhao]

Hi list,

I build a flow graph with both transmitter and receiver, and the forward
path works fine. Then I want to let receiver block to feedback some data
to the transmitter block, and I learn that GNU Radio does not allow the
flow graph has loops. Now I'm trying to walkaround the limitation by
using udp_sink and udp_source, but I haven't make it work.

I find that if I connect udp_source to a file_sink, the output file does
contain correct data and receiver works well. But if I connect
udp_source directly to the block in transmit path, the receiver cannot
receive any data. I guess it is due to the chicken-egg problem. Will it
help if udp_source outputs some initial value when the connecting port
has no data?  What is the right way to make feedback work?

-- 
alick
Fedora 16 (Verne) user
https://fedoraproject.org/wiki/User:Alick