I'm still in way over my head here but some progress:
usrp_wfm_rcv(_nogui).py runs with either the Basic Rx or TV Rx board. Since most of the FM stations are 4 to 6 miles away, it is easy to get strong signals. I get uO errors which I think means the USRP is reporting errors sending bytes in thru the USB path. I get more when running Gnome or xdm than with the nogui version. I think the following shows the USRP can send 4Mb/s but anything over 4 Mb induces overruns: ./test_usrp_standard_rx -M 1 RX d'board A: Basic Rx RX d'board B: TV Rx xfered 1.05e+06 bytes in 0.256 seconds. 4.089e+06 bytes/sec. cpu time = 0.008566 noverruns = 0 ./test_usrp_standard_rx -M 2 RX d'board A: Basic Rx RX d'board B: TV Rx xfered 2.1e+06 bytes in 0.512 seconds. 4.093e+06 bytes/sec. cpu time = 0.0179 noverruns = 0 ./test_usrp_standard_rx -M 3.9 RX d'board A: Basic Rx RX d'board B: TV Rx xfered 3.15e+06 bytes in 0.768 seconds. 4.094e+06 bytes/sec. cpu time = 0.02703 noverruns = 0 ./test_usrp_standard_rx -M 4 RX d'board A: Basic Rx RX d'board B: TV Rx rx_overrun xfered 4.19e+06 bytes in 1.02 seconds. 4.094e+06 bytes/sec. cpu time = 0.03876 noverruns = 1 ./test_usrp_standard_rx -M 7.9 RX d'board A: Basic Rx RX d'board B: TV Rx rx_overrun rx_overrun xfered 7.34e+06 bytes in 1.79 seconds. 4.095e+06 bytes/sec. cpu time = 0.06075 noverruns = 2 ./test_usrp_standard_rx -M 8 RX d'board A: Basic Rx RX d'board B: TV Rx rx_overrun rx_overrun xfered 8.39e+06 bytes in 2.05 seconds. 4.095e+06 bytes/sec. cpu time = 0.06814 noverruns = 2 Disabling the ethernet interface seems to have some small effect on the overruns while running the wfm code and listening to FM but they still do hit occasionally and can be heard in the audio. I am running the "GENERIC" kernel at the moment so there are probably a few other things turned on that need not be. The data sheet for my I82801DB chip says it should do 480MB/s using USB 2.0 but that probably really is 60 MBytes/s meaning it should do better than the obvious 4MB/s limit I see. Some of the scripts in the usrp/host/apps use #!/bin/bash and others use #!/usr/local/bin/bash instead of #!/usr/bin/env bash as done elsewhere. Progress but as always clues are welcome. -- LRK [EMAIL PROTECTED] _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
