-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I'm running some experiments with my two USRP2's - as I want to get synchronized samples out of them. I have the clock's locked to my external 10Mhz, and they sync_to_pps correctly (i.e. the timestamp resets on the next PPS). However, the difference between timestamps from the two USRP2's does not seem to be a constant at low data rates: they are constant between subsequent received frames (i.e. USRP2 A vs. USRP2 B) - but each time I start my application, or even if I send sync_to_pps commands while streaming, the difference changes. I'm trying to figure out if this is due to some non-deterministic timing on the USRP2, or some other source. At higher data rates (e.g. decimation <= 16), the difference between timestamps from the two USRP2's gets more erratic, and tends to fluctuate (quite wildly down at -d 4). My plan has been to setup buffers to align samples based on timestamp - but with such variations it looks to me like it could be quite difficult to implement. Or at the very least, I'd need very large buffers, and could end up needing/wanting to change their size often. Any suggestions on how to best deal with this? Should I be looking into the USRP2 firmware code to try to get some more predictable behavior out of it? Thanks, Doug
- -- Doug Geiger Research Assistant Communications and Signal Processing Lab Oklahoma State University http://cspl.okstate.edu douglas.gei...@okstate.edu doug.gei...@ieee.org -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (Cygwin) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFJ5OHKgfOzzR5bXIgRAlkzAJ9PJBBrzXgvgi7ZxFaFz96IZal28ACghE+D LtLDt7yvoHqnThKVUGv2CQ8= =j2wh -----END PGP SIGNATURE----- _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
