[ntp:questions] need help installing gps with ntp on Linux
Uwe Klein
uwe at klein-habertwedt.de
Sat Feb 11 11:09:41 UTC 2012
Ron Frazier (NTP) wrote:
> Hi all,
>
> I have recently been posting messages about my experience trying to
> install a USB GPS and wring out the maximum performance in Windows.
>
> Now I need help doing the same thing in Linux. I want to install the
> GPS using only NTPD if possible, without GPSD, to make my install
> configuration as close as possible to the way it's set up in Windows.
> Please let me know if I'm on track or not and why my GPS is not working,
> if possible.
>
> I'm running Ubuntu 11.04 and had already installed NTP version
> 1.4.2.6.p2 from the Ubuntu Natty repositories. That runs fine, polling
> from the internet.
>
> I plugged in the USB GPS and it appeared as /dev/ttyUSB0. I used the
> following configuration line to set up the port:
>
> From: http://www.satsignal.eu/ntp/Sure-GPS.htm
>
> I used: stty -F /dev/ttyUSB0 57600 igncr clocal -echo -ixon
>
> Then, I used the following command to set up a symlink to the port:
>
> ln -T /dev/ttyUSB0 /dev/gps1 (Actually, I tried gps5 first.)
>
> Then, I did cat /dev/gps1 and got the following:
>
> ron at asus-k52f-1:/etc$ cat /dev/gps1
> $GPZDA,011724.000,11,02,2012,,*54
> $GPZDA,011725.000,11,02,2012,,*55
> $GPZDA,011726.000,11,02,2012,,*56
> $GPZDA,011727.000,11,02,2012,,*57
> $GPZDA,011728.000,11,02,2012,,*58
> $GPZDA,011729.000,11,02,2012,,*59
> $GPZDA,011730.000,11,02,2012,,*51
> $GPZDA,011731.000,11,02,2012,,*50
>
> So, I know the port is working and I know the GPS is putting out data.
>
> Before editing the ntp.conf file, I stopped the service using:
>
> sudo /etc/init.d/ntp stop
>
> These are the GPS lines in /etc/ntp.conf:
>
> server 127.127.20.1 prefer minpoll 3 maxpoll 3 mode 72
> fudge 127.127.20.1 time2 0.3000 refid GPS1
last year I played around with the Sure Board.
see http://wiki.tcl.tk/28358
for me the mode keyword did not work the way it was supposed.( baudrate wise )
check what the baudrate is after ntp has started.
Look in the log : /var/log/messages or /var/log/ntp/* for errors.
I am running on SuSE, log destination tend to vary over distributions.
uwe
More information about the questions
mailing list