Re: Multiple TPV lines per sec?

[Gary E. Miller]

Yo Tor!

On Fri, 29 Jan 2021 13:05:39 +0100
Tor Rune Skoglund <trs@fourc.eu> wrote:

> Sometimes, we get multiple TPV lines per seconds from gpsd, e.g.
> using gpspipe.

Yeah multiple TPV per cycle is common and expected.  As your NMEA
dribbles info to gpsd, gpsd can only dribble it to the client.

Solutions are to run your GNSS receiver in binary mode, or optimize
your NMEA.

> After restarting gpsd, one of the lines go away.

When gpsd starts, absent the -b or -p options, it tries to reconfigure
your receiver for better performance.

> We done some tests, but have not reached a good conclusion yet apart 
> from it helps if we delay starting/restarting gpsd too soon during
> boot or after a new GNSS device has been added to the system.

Fast restart interrupts the gpsd autodetection and reconfiguration.

> Any quick, initial pointers and ideas on under which circumstances
> gpsd => gpspipe would report more than one TPV message per sec would
> be appreciated.

Without knowing your receiver model, or how it is configured, hard to
give any guidance.

RGDS
GARY
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Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
        gem@rellim.com  Tel:+1 541 382 8588

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