A C wrote:
On 8/20/2011 17:41, David Lord wrote:
My config for NetBSD-5.1 on i386:
# GPS Sure serial tty00 /dev/gps2
server 127.127.20.2 mode 18 prefer
fudge 127.127.20.2 time2 0.350 refid GPSb
server 127.127.22.2
fudge 127.127.22.2 flag2 0 flag3 1 refid PPSb
The Sure output is at a higher baud rate than default hence the
use of 'mode 18'.
offset
*GPS_NMEA(2) GPSb 0 377 -80.444 6.309
oPPS(2) PPSb 0 377 -0.013 0.004
Offset is normally lower than above but peaks at 25-30us when
system is under heavy load.
I've reconfigured like yours and tried it, too (with the addition of a
minpoll to speed up the GPS):
server 127.127.20.1 minpoll 4 mode 1 prefer
fudge 127.127.20.1 time2 0.245 refid GPS
server 127.127.22.1
fudge 127.127.22.1 flag2 0 flag3 1 refid PPS
But this is what ntpq gives me after a bit:
remote refid st t when poll reach delay offset
jitter
==============================================================================
*169.229.70.183 169.229.128.214 3 u 46 64 177 36.840 -5.794
0.280
+204.9.54.119 .CDMA. 1 u 38 64 177 73.723 -1.932
1.302
+127.127.20.1 .GPS. 0 l - 16 377 0.000 -13.713
7.456
127.127.22.1 .PPS. 0 l - 64 0 0.000 0.000
0.000
And the log files:
21 Aug 01:34:44 ntpd[7159]: 169.229.70.183 8011 81 mobilize assoc 2677
21 Aug 01:34:44 ntpd[7159]: 204.9.54.119 8011 81 mobilize assoc 2678
21 Aug 01:34:44 ntpd[7159]: GPS_NMEA(1) serial /dev/gps1 open at 4800 bps
21 Aug 01:34:44 ntpd[7159]: GPS_NMEA(1) 8011 81 mobilize assoc 2679
21 Aug 01:34:44 ntpd[7159]: PPS(1) 8011 81 mobilize assoc 2680
21 Aug 01:34:44 ntpd[7159]: 0.0.0.0 c016 06 restart
21 Aug 01:34:45 ntpd[7159]: 0.0.0.0 c012 02 freq_set kernel -74.006 PPM
21 Aug 01:34:45 ntpd[7159]: 169.229.70.183 8024 84 reachable
21 Aug 01:34:47 ntpd[7159]: 204.9.54.119 8024 84 reachable
21 Aug 01:34:47 ntpd[7159]: GPS_NMEA(1) 8024 84 reachable
21 Aug 01:37:58 ntpd[7159]: 169.229.70.183 963a 8a sys_peer
21 Aug 01:37:58 ntpd[7159]: 0.0.0.0 c615 05 clock_sync
21 Aug 01:38:00 ntpd[7159]: PPS(1) 802b 8b clock_event clk_no_reply
21 Aug 01:42:06 ntpd[7159]: ntpd exiting on signal 2
No reply from the PPS clock at all.
I have another couple of settings that might be needed.
tos minsane 3
tos orphan 10
tos mindist 0.5
I've also been using different ntpd versions without problem:
4.2.4p6 stock NetBSD base
4.2.7p98 dev release
4.2.6p3
I used parallel port PPS for a while with 4.2.7p98 again
without problem other than I lost use of printer port.
The ntpd releases etc are not compatible with each other
or different kernel versions which is no big deal as I
install ntpd along with netbsd kernel and base system.
In another thread it was pointed out that the DCD pulse from
the GPS might be too short and it's worth checking with a
scope or I've used radioclkd2 debug mode which gives a list
of pulse lengths. A monostable pulse expander can be used if
you can't set pulse length it by configuration of the gps.
The gps I've tried have all given adequate pulse lengths.
David
_______________________________________________
questions mailing list
[email protected]
http://lists.ntp.org/listinfo/questions
