Re: [chrony-users] Using gpsd

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William G. Unruh __| Canadian Institute for|____ Tel: +1(604)822-3273
Physics&Astronomy _|___ Advanced Research _|____ Fax: +1(604)822-5324
UBC, Vancouver,BC _|_ Program in Cosmology |____ unruh@xxxxxxxxxxxxxx
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On Tue, 19 Mar 2024, David Campbell wrote:

[CAUTION: Non-UBC Email]

I missed the "For example" bit, thanks for the clarification.

Reading the documentation again, I only can get the first example to work, so there
is no delay or offset.

# First option
refclock SOCK /var/run/chrony.ttyS0.sock refid GPS

On my system, /var/run is a link to /run. I think it was at least 5 years ago
that it was switeched from /var/run to /run

# Second option
refclock PPS /dev/pps0 lock NMEA refid GPS
refclock SOCK /var/run/chrony.clk.ttyS0.sock offset 0.5 delay 0.1 refid NMEA nosele

That says that the system is .5 sec out? Hard to believe. Maybe you are using
the wrong part of the pulse (clear rather than assert?)

What makes you think you need the offset and delay set?

On 3/19/24 17:39, Bill Unruh wrote:

      On Tue, 19 Mar 2024, David Campbell wrote:

            [CAUTION: Non-UBC Email]

            Also, the device path given by chrony is out of date and
            the one given by gpsd works: that is
            "/run/chrony.XXXX.sock" instead of
            "/var/run/chrony.clk.XXXX.sock". If I am wrong about the
            paths, I don't know how chrony works, but only the former
            works for me.

      man chrony.conf

                     Unix domain socket driver. It is similar to the SHM
      driver, but
                     samples are received from a Unix domain socket instead
      of shared
                     memory and the messages have a different format. The
      parameter is the
                     path to the socket, which chronyd creates on start. An
      advantage over
                     the SHM driver is that SOCK does not require polling and
      it can
                     receive PPS samples with incomplete time. The format of
      the messages
                     is described in the refclock_sock.c file in the chrony
      source code.

                     An application which supports the SOCK protocol is the
      gpsd daemon.
                     The path where gpsd expects the socket to be created is
      described in
                     the gpsd(8) man page. For example:

                         refclock SOCK /var/run/chrony.ttyS0.sock

      See the words "For example:? Ie, the man page says to use what gpsd
      says the the
      path is.

      Note that path could well be different for different versions of Linux.

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