On Mon, Sep 11, 2017 at 03:01:13AM +0000, Simon Haines wrote:
> The GPS is connected through gpsd using the SHM driver, and I've confirmed
> it is working (refclock log is below). Here is my chrony.conf:
> # cat /etc/chrony.conf
> refclock PPS /dev/pps0 lock NMEA
> refclock SHM 0 offset 0.5 delay 0.2 refid NMEA noselect
Try changing the offset to 0.1. From the log below it looks like the
offset between the two refclocks is too large and prevents their
locking.
Yes, this now works as expected. I now see the log entries 'refclock pulse ignored offdiff=0.38' and understand this relates to the delta between locking clocks, and not the system time.
Please note that the second argument of makestep is number of updates
and not seconds.
OK, I had assumed one update per second from both refclocks. There is no reason to restrict the number of updates in this way for my use case, and I've extended the configuration to the default 1000 updates.
Many thanks for helping with this.
Simon.