Hi The gotcha is that the jitter on the base pps output is high enough in this case that doing a reasonable check (roll over … ) is not as simple as it should be. Best guess is that uBlox has a bug in their GPS side of things. Pretty much par for the course on something this new.
Bob > On Feb 16, 2019, at 3:59 PM, Achim Gratz <[email protected]> wrote: > > Mark Sims writes: >> For all the receivers that I have tested there is only one combination >> that jumps out as being the correct one. However, for the new Ublox >> F9P, there are two combinations that produce virtually identical >> measurements and statistics (add current sawtooth or subtract previous >> sawtooth). Any ideas on how to determine which combination is the >> "correct" one? > > I don't think that uBlox changed the defaults over their previous > generation, so whatever worked for the M8 series should be applicable > here. If you're using the UBX-TIM-TP message data, this always applies > to the TIMEPULSE0 output following the message. The message and the > measurement rate as well as the PPS frequency need to match up for this > to work as expected. > > Now, if you want to check, I think you need to wait for a clear > wraparound to appear in the sawtooth correction, which should coincide > with a cycle slip on the next PPS pulse (not the previous one). > > > Regards, > Achim. > -- > +<[Q+ Matrix-12 WAVE#46+305 Neuron microQkb Andromeda XTk Blofeld]>+ > > Waldorf MIDI Implementation & additional documentation: > http://Synth.Stromeko.net/Downloads.html#WaldorfDocs > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
