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
