Timestamp Error on Receive

GNU Radio
1

I’m getting unexplained behavior receiving timed samples in continuous
mode with yesterday’s merge. First run after boot is fine, but I get
overruns and a bizarre timestamp on subsequent runs. This occurs with
the
USRP2 and N210. Running rx_timed_samples with the following diff
reproduces the issue. Thoughts? Thanks.

Thomas

–Cold start
Begin streaming 1000 samples, 3.000000 seconds in the future…
Got packet: 362 samples, 3 full secs, 0.000000 frac secs
Got packet: 362 samples, 3 full secs, 0.000058 frac secs
Got packet: 362 samples, 3 full secs, 0.000116 frac secs

–Subsequent runs
Begin streaming 1000 samples, 3.000000 seconds in the future…
OGot packet: 362 samples, 3 full secs, 0.129991 frac secs
OGot packet: 362 samples, 3 full secs, 0.000058 frac secs
Got packet: 362 samples, 3 full secs, 0.000116 frac secs

diff --git a/host/examples/rx_timed_samples.cpp
b/host/examples/rx_timed_samples.cpp
index a19532f…e3f60ee 100644
— a/host/examples/rx_timed_samples.cpp
+++ b/host/examples/rx_timed_samples.cpp
@@ -82,8 +82,7 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){
std::cout << boost::format(
“Begin streaming %u samples, %f seconds in the future…”
) % total_num_samps % seconds_in_future << std::endl;

  • uhd::stream_cmd_t
    stream_cmd(uhd::stream_cmd_t::STREAM_MODE_NUM_SAMPS_AND_DONE);
  • stream_cmd.num_samps = total_num_samps;
  • uhd::stream_cmd_t
    stream_cmd(uhd::stream_cmd_t::STREAM_MODE_START_CONTINUOUS);
    stream_cmd.stream_now = false;
    stream_cmd.time_spec = uhd::time_spec_t(seconds_in_future);
    sdev->issue_stream_cmd(stream_cmd);
    –
    1.7.3.4