David Woolley schrieb: > Nicola Berndt wrote: > >> I have now successfully set up my machine to use a usb-gpd-mouse to set >> > > Not a good idea. USB serial ports have high latency and jitter and NMEA > feeds also tend to have high jitter, as they are designed for > navigation, not for time. You need a PPS signal on an ISA or PCI serial > port interface. > > I konw, but setting up pps failed due to noise on my pps line, wich I had not time to really investigate yet. There is a thread connected to that some days earlier on this list. I need the nmea-time for now, in order to get things started.. PPS will follow very soon.. >> the time. Strangely every time I reboot I get results like this, wich >> settle down after a (not so short) while: >> >> remote refid st t when poll reach delay offset >> jitter >> ============================================================================== >> GPS_NMEA(0) .GPS. 0 l 9 64 37 0.000 -580.75 >> 3965.19 >> > > You've not had your first 8 samples yet. You haven't actually had > enough for ntpd to act on the data. You can speed that up with iburst, > but ntpd will still take a long time to get a very tight lock. jitter > will reduce as you get to the eight samples. The good? think, is that > you are more than 128ms out, so that ntpd will step the time, to zero > the offset, once it gets enough samples. > > Thx for the iburs hint, I will try that.
Still very strange is that offset, wich also occurs when using network-server from a ntp-pool.. >> The problem is, that this takes rather long and the computer's job >> actually is, to provide exact time outdoors right after booting.. >> > > It is possible to get within about 10ms in two or three minutes. > > _______________________________________________ > questions mailing list > [email protected] > https://lists.ntp.org/mailman/listinfo/questions > _______________________________________________ questions mailing list [email protected] https://lists.ntp.org/mailman/listinfo/questions
