fairwaves / UHD-Fairwaves

Fairwaves version of the UHD drivers, tweaked to support Fairwaves UmTRX.
http://umtrx.org
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clock is drifting with timed commands #19

Open alexeyzhuchkov opened 7 years ago

alexeyzhuchkov commented 7 years ago

I have observed drift in the fpga clock. I am using tags in GNU Radio to transmit a packet on every PPS. But when I see the PPS and packet on an Oscilloscope I see that the packet is continuously moving away from PPS. Sometimes it moves away faster some time slower. What could cause this? The PPS is coming from GPSDO firefly1-A.

We are using "tx_time" tags, used in GNU Radio, for controlled transmission. Tags are working but the clock is drifting. The packet is continuously moving away from the PPS.