Pardon me for jumping in here - I have exactly the same config Tom mentions (Oncore GPS, TAPR interface board); but have been using the NMEA driver and trying to hack the Linux kernel (Ubuntu) to do PPS.
This seems like perhaps an easier way - Tom, can you post the details on the OnCore driver? Thanks in advance! Clay N7QNM > On 2009-12-28, xyz-2041 <xyz2...@gmail.com> wrote: >> Plugged in the GPS unit's serial cable into a Windows >> computer running WinOncore12 v1.0 (Build 37): >> >> http://www.google.com/#q=WinOncore12Installation.exe >> >> Seemed to work without any problems. Generated >> all sort of graphs and charts. Let it run and it >> told me exact latitude, longitude and height above >> sea level. >> >> Used an analog volt meter and from pin 5 (supposed >> to be ground), I only noticed voltage on pins 2 and 3. >> Pin 2 was going erratically negative once a second. >> I believe that this must be received data as per >> standards. Pin 3 was +5 volts, but dropping to >> -5 volts once per second. >> > You did not mention how your Oncore receiver was being interfaced to > your computer or it's model number. I use one of the TAPR boards and > Oncore UT+ combination. The NTP refclock driver for the Oncore includes > the code for receiving the PPS signal on the computer DCD pin. > >> I've changed my configs a bit, /var/log/ntp.log and >> /var/log/ntpd.log don't show any errors. >> >> However, "ntpq -c pe" still doesn't show any response: >> >> GPS_NMEA(0) .GPS. 0 l - 16 0 0.000 >> 0.000 0.001 >> PPS(0) .GPS. 0 l - 16 0 0.000 >> 0.000 0.001 >> GPS_ONCORE(0) .GPS-. 0 l - 16 0 0.000 >> 0.000 0.001 >> > You should not be using GPS_NMEA or PPS. The type 30 refclock > communicates with the receiver using Motorola Binary protocol. You may > need to use WinOncore to set your receiver communications to use the > binary protocol or even better, reset the receiver to factory defaults. > Your config files already have your position defined, so there is no > need to have anything in your receiver at startup. The almanac will be > received while NTP is settling down after startup. You will need to > configure at least 4 other NTP servers to speed up the initial startup. > The refclock code wants to have a synchronized NTP server before adding > itself to the peer selection. I find about 30 minutes after a cold > start my PPS LED will start to flash and I observe that my Oncore gets > selected. > >> - Create symbolic links: >> >> ln -s /dev/cuad0 /dev/oncore.pps.0 >> ln -s /dev/cuad0 /dev/oncore.serial.0 >> ln -s /dev/cuad0 /dev/gps0 >> ln -s /dev/cuad0 /dev/pps0d >> >> - Create /etc/devfs.conf links: >> >> link cuad0 pps0 >> link cuad0 gps0 >> link cuad0 oncore.pps.0 >> link cuad0 oncore.serial.0 >> >> > I think that you will find that the symbolic links in /dev are not > required and > only the /etc/devfs.conf entries are all you will need. You won't need > either pps0 or gps0 entries for anything. Only the oncore* stuff is > needed for the refclock type 30. > > Tom > > --- > Public Keys: > PGP KeyID = 0x5F22FDC1 > GnuPG KeyID = 0x620836CF > > _______________________________________________ > questions mailing list > questions@lists.ntp.org > https://lists.ntp.org/mailman/listinfo/questions > > _______________________________________________ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
