[ntp:questions] ntpd connect gpsd shared memory driver

Rob nomail at example.com
Tue Jun 18 16:27:17 UTC 2013

Richard Cagley <rcagley at gmail.com> wrote:
> On Tue, Jun 18, 2013 at 12:22 AM, A C <agcarver+ntp at acarver.net> wrote:
>> You need -n (lower case N) to force gpsd to start collecting data
>> automatically.  It normally waits for something to connect to its TCP port
>> and enable data collection (the WATCH command as you discovered). If you
>> start with just:
>> gpsd -bn /dev/ttyO0
>> You'll find the SHMs are populated after a few seconds (once gpsd syncs
>> with the data stream from the receiver).
> Hmmm, i had tried the -n before. It doesn't seem to help. After several
> minutes there is no change to  ntpq -p. Any other ideas for something
> stupid I'm doing? Do you think it's a ntpd or gpsd issue...or something
> else?
> After several minutes, no change to ntqp -p
> ---
> / # ntpq -p
>      remote           refid      st t when poll reach   delay   offset
>  jitter
> ==============================================================================
>  SHM(0)          .SHM.            0 l    -   16    0    0.000    0.000
> 0.000
> ---

As I wrote before, your ntp config is not correct.  please copy it
from the docs.  However, that is not the cause of the problem.
(it would be the cause of severe inaccuracy once you obtain NMEA data
as you are not using PPS)

> but gpsd seems to be active...

What you posted here looks OK but is too short to diagnose the
situation.  You need to paste more logging to see if there is lock
to the satellites.

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