Re: Adafruit USB and PPS

[Gary E. Miller]

Yo Neal!

On Tue, 26 Nov 2019 08:44:17 +0000
Neal Dillman <address@hidden> wrote:

> That device purports to support PPS output on RI (Ring Indicator)
> serial control pin via USB (3rd bullet down in the description).
> That is what I would like to take advantage of.

Sorry, I missed that.  Almost no GPS over USB support PPS, so I jumped
to that conclusion.

>  My impression is
> that gpsd should be able to work with that.  No?

Yup, works fine.  I have several GR-601W (Navisis GPS/PPS over USB)
running all the time  Zero configuration needed.

As Anders Wallin point out:

    ppstest and ppswatch should show if your hardware (and kernel?)
    configuration is working, something like this:
    https://lists.nongnu.org/archive/html/gpsd-users/2019-10/msg00025.html

To verify your GPS, with gpsd not running:

     ~ # ppscheck /dev/ttyUSB0
     # Seconds  nanoSecs   Signals
     1574796652.735051267 TIOCM_CD
     1574796652.999830288
     1574796653.099824781 TIOCM_CD
     1574796653.999830052
     1574796654.099836884 TIOCM_CD

Be sure your gpsd is compiled with KPPS support.

Also interesting is to send the list the first 40 lines of:

        # gpsd -D 5 -N -n /dev/pps0 /dev/ttyUSB0 |& fgrep PPS

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

            Veritas liberabit vos. -- Quid est veritas?
    "If you can't measure it, you can't improve it." - Lord Kelvin

pgpwsUixfRex2.pgp
Description: OpenPGP digital signature