Re: gpsd losing connection to ublox

[Gary E. Miller]

Yo Niall!

On Mon, 8 Nov 2021 12:38:24 -0800
Niall Parker <stuff@npengineering.ca> wrote:

> I've setup gpsd and ntpsec as per the GPSD Time Service HOWTO, using
> a locally compiled gpsd v 3.23.1 instead of distribution version
> (Nvidia Jetson with Ubuntu 18.04). Managed to get PPS working after
> sorting the device tree and the system seems to work as expected
> initially.

Cool.  But you do not mention your GPS receiver model.

You can get it this way:

$ ubxtool -p MON-VER

The results may look like this:

UBX-MON-VER:
  swVersion 6.02 (36023)
  hwVersion 00040007


> After running for a short period of time though, gpsd seems to lose 
> connection to the GPS (a ublox module connected to /dev/ttyTHS1). It 
> will get a few updates then nothing for a minute or more, then maybe
> a couple more updates and another delay. Often cgps will fail with a
> timeout.

Hard to say without seeing a -D4 log.

You could try forcing the port speed (-s) or updating to git head.

> I've confirmed no delays or lost packets when just looking at serial 
> output from GPS without gpsd running. I don't think power management
> is the issue,

Easy to spot, I assume no lightning bolt on your HDMI?

> the board is moderately busy running 30-40% CPU most of
> the time. Could it be too busy for gpsd ???

That should be OK.

> Any hints on how to trace the loss of connection would be
> appreciated, thanks.

You can grab a log and send it here, as root:

# gpsd -nND 4 /dev/ttyS0 > tmp.log 2>&1

Let it run until it fails.  Then send tmp.log here.

RGDS
GARY
---------------------------------------------------------------------------
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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