# 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
ct
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?
...