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@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
