[ntp:questions] What is the NTP recovery time from 16s step in GPS server?
nomail at example.com
Tue Oct 30 19:45:12 UTC 2012
David Taylor <david-taylor at blueyonder.co.uk.invalid> wrote:
> On 30/10/2012 17:59, Rob wrote:
>> When I wrote that part of gpsd, I implemented the proper checks so
>> that the time is only put in the SHM after the GPS receiver has
>> indicated that it has a valid fix on the satellites.
> THanks for this information, Rob. In this case the GPS appears to have
> a valid fix, but it is outting GPS time and not UTC. There must be a
> flag in the Trimble TSIP which tells you this, as I've seen the same
> when monitoring with the Trimble Studio software. It takes some time
> for the switch-over to occur.
Are you using NMEA mode or TSIP mode on that receiver?
I wrote the TSIP driver and checked the original source and the
current version 3.7, and in the processing of the packet 0x41 there
is a check on the validity of the GPS-UTC offset (called leap seconds
in the comment, I believe this name is from the Trimble docs).
The time is only valid when the number of leap seconds is more than 10.
I would hope that the value is 0 as long as the real value has not yet
Can you try to set the log level to INFO and see what is going wrong?
The code is in driver_tsip.c and logs the offset as the last number
in this log line:
gpsd_report(LOG_INF, "GPS Time %f %d %f\n", f1, s1, f2);
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