I've got a flow-graph with a throttled random byte source, which is a test input for a modulator:
http://www.sbrac.org/files/fm4_test_modulator.grc http://www.sbrac.org/files/fm4_test_modulator.py The source is throttled to the byte rate required to produce the correct number of symbols/second (4800). What I've noticed is that this graph only runs in "fits and starts", rather than continuously. I assume this has something to do with the Gnu Radio buffering and internal scheduler. In the case of a "real" flow-graph, taking real data in at 4800symbols/second, going to a real USRP transmitter, will it still run in "fits and starts" or will it "do the right thing"?? I realize that buffering is an important part of Gnu Radio, but how do you actually send low-rate data in something approaching correct real-time? I at first thought this was due to the throttle block, so I replaced it with an external (via a FIFO) source that produced random bytes at a 1200-bytes/second rate (2 bits/symbol), and it behaves exactly the same as a a throttled random source--the graph seems to run in "fits and starts". -- Marcus Leech Principal Investigator Shirleys Bay Radio Astronomy Consortium http://www.sbrac.org _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
