On Wed, Dec 15, 2010 at 2:04 PM, Josh Blum <[email protected]> wrote: > >> It would be really nice if the send-function in the API have a TDMA >> mode where fragments of samples are dropped when an underrun occur so >> that the majority of the samples are aligned to the >> start_of_burst_time (see above example (1) and (3)). With this >> feature it is not necessary for the programmer to know if an underrun >> has occurred and how to handle this. Instead the programmer knows >> that if an underrun occurred some samples are dropped but the rest of >> the sample are transmitted at the expected time without any offset. >> Is this doable? >> > > This should already be the case. If you timestamp every packet, then the > underflow recovery is handled by hardware. That is, the FPGA will drop > until the timestamp is <= current time, and then wait until the > timestamp == current time, so realignment is automatic.
I believe you mean timestamp is >= current time. Regardless though, this is not the case based on my observations. > Are you timestamping every packet? This calculation should be > last_time_spec + time_spec_t(0, num_samps_in_last_packet, host_sample_rate) Yes. I timestamp every packet. I also mark every packet start_of_burst. I wonder if late unmarked packets will still transmit, though this would not remove the necessity of detecting underruns on the host. Thomas _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
