[ntp:questions] need help installing gps with ntp on Linux
Ron Frazier (NTP)
timekeepingntplist at c3energy.com
Sat Feb 11 01:39:41 UTC 2012
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
$GPZDA,011731.000,11,02,2012,,*50
So, I know the port is working and I know the GPS is putting out data.
Before editing the ntp.conf file, I stopped the service using:
sudo /etc/init.d/ntp stop
These are the GPS lines in /etc/ntp.conf:
server 127.127.20.1 prefer minpoll 3 maxpoll 3 mode 72
fudge 127.127.20.1 time2 0.3000 refid GPS1
This is the same thing that works in Windows, except for the port number.
Then, I restarted NTPD with:
sudo /etc/init.d/ntp start
When I do ntpq -p, I get:
ron at asus-k52f-1:/etc$ ntpq -p
remote refid st t when poll reach delay offset
jitter
==============================================================================
*nist1-ny.ustimi .ACTS. 1 u 18 512 1 59.006 -3.796
2.559
-216.119.63.113 .ACTS. 1 u 15 512 1 60.587 12.887
2.619
-india.colorado. .ACTS. 1 u 21 512 1 58.931 -10.283
1.089
#ping-audit-207- .ACTS. 1 u 18 512 1 83.298 -42.531
1.240
-alice.ziaspace. 209.51.161.238 2 u 21 512 1 51.124 -3.522
2.379
-clock01.mifl01. 128.118.25.5 2 u 16 512 1 69.476 5.781
2.733
-jtsage.com 127.67.113.92 2 u 15 512 1 54.499 -2.492
1.918
+clock-b.develoo 164.67.62.199 2 u 14 512 1 82.772 -4.697
1.941
+ntp2.Rescomp.Be 128.32.206.55 2 u 13 512 1 93.910 -5.478
2.941
-guinness.mcguyv 216.218.254.202 2 u 12 512 1 84.256 -3.343
1.944
-mailman.pittsbu 127.67.113.92 2 u 11 512 1 46.289 -7.461
2.583
#ip-173-201-38-8 198.153.152.52 2 u 11 512 1 94.652 -15.700
3.057
europium.canoni .INIT. 16 u - 512 0 0.000
0.000 0.000
Unfortunately, there is no sign of my GPS anywhere.
Can anyone tell me what's wrong?
Thanks in advance.
Sincerely,
Ron
--
(PS - If you email me and don't get a quick response, don't be concerned.
I get about 300 emails per day from alternate energy mailing lists and
such. I don't always see new messages very quickly. If you need a
reply and have not heard from me in 1 - 2 weeks, send your message again.)
Ron Frazier
timekeepingdude AT c3energy.com
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