Re: 3.22 not sending PPS to SHM

[Gary E. Miller]

Yo David!

On Tue, 12 Jan 2021 15:10:09 +0000
David Taylor <gm8arv@yahoo.co.uk> wrote:

> Yes, I see two PPS devices:
> 
>    pi@RasPi-22:~ $ ls /dev/pps*
>    /dev/pps0  /dev/pps1

As you should expect.

> These appear after some boot-time configuration commands.

As you provided elsewhere.

> I am only running gpsd from the command line right now.

Fine, just don't use systemd(umb) to start gpsd.

> I've had issues with 
> automating this in the past so I thought to start the easier way!

Trivial, just add the one line you use on the command line to
your start script.  On gentoo:

# echo "gpsd /dev/ttyAMA0 -s 115200 -n /dev/pps0" >> /etc/local.d/local.start


>    sudo gpsd /dev/ttyS0 -s 115200 -n -F /var/run/gpsd.sock

Uh, the serial port on a RasPi is /dev/ttyAMA0, not /dev/ttyS0.  So the
/dev/ttyS0 might be a symlink to /dv/ttyAMA0, but do not count on thar.
Use the primary device (ttyAMA0).

> so I'm unsure how gpsd knows about the PPS device.

Because you tell it.

> sudo ppstest /dev/pps0
> trying PPS source "/dev/pps0"
> found PPS source "/dev/pps0"
> ok, found 1 source(s), now start fetching data...
> source 0 - assert 1610463934.000000417, sequence: 31086 - clear  0.000000000, 
> sequence: 0

And there it is, you just forgot to tell gpsd where it was.

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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