[ntp:questions] What is the NTP recovery time from 16s step in GPS server?

Rob 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
been determined.

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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