On Tue, 30 Dec 2008 17:24:36 GMT, "David J Taylor" <[email protected]> wrote:
>George R. Kasica wrote: >[] >> Next step....I added back GPS NEMA data without the gpsd daemon (I >> don't pass the data out to anywhere so there's no real need for it) >> >> and I see >> >> # ntpq -p >> remote refid st t when poll reach delay offset >> jitter >> ============================================================================== >> xGPS_NMEA(0) .GPS. 0 l 13 16 377 0.000 -616.37 >> 10.466 >> *SHM(0) .PPS. 0 l 14 16 377 0.000 -0.557 >> 0.712 >> eagle-local 192.168.1.7 2 u 36 64 377 0.153 -44.398 >> 0.607 >> apollo-local 192.168.1.7 3 u 24 64 377 0.250 -16.713 >> 1.912 >> -mirror 209.132.176.4 2 u 29 64 377 10.272 6.391 >> 135.974 >> +tesla.fireduck. 198.82.1.202 3 u 28 64 377 36.123 2.841 >> 115.565 >> +rikku.vrillusio 209.51.161.238 2 u 21 64 377 38.531 -3.260 >> 156.267 >> >> >> I have good PPS and am getting GPS NEMA in as well but the offset for >> the NEMA data seems quite large....what would I do to fix that?? >> >> George > >George, > >On my FreeBSD system, the ntpq -p output looks like this (some servers >omitted): > > remote refid st t when poll reach delay offset >jitter >============================================================================== >-utserv.mcc.ac.u 193.62.22.98 2 u 58 64 377 25.548 3.732 >2.715 >*GPS_NMEA(1) .PPS. 0 l 52 64 377 0.000 0.002 >0.008 > >With just the reference clock type 20, I get the accuracy needed. The PPS >line from the GBS-18 LVC is wired to the DCD line of the serial port. In >my ignorance, I don't see why you even need the SHM driver, but as I said >before, I'm no expert! I don't see why my system picks up the PPS from >just the type 20 driver, and yours does not. > Do you have the PPS kernel hack compiled in? That may be doing it for you. I can't easily add that here with the Fedora Core 9 RPM kernel I have. What are you using in your ntp.conf settings for the clock setup lines and fudge? George _______________________________________________ questions mailing list [email protected] https://lists.ntp.org/mailman/listinfo/questions
