> On 19/02/2016, at 12:07 PM, Tomalak Geret'kal <t...@kera.name> wrote: > > On 18/02/2016 22:48, Deven Hickingbotham wrote: >> >>> $cat /sys/class/pps/pps0/assert >>> 1455831692.018636856#178 >>> >>> Are you seeing those? >>> >> >> Yes, but just one timestamp per execution: >> >> pi@gps ~ $ cat /sys/class/pps/pps0/assert >> 1455835119.289108505#4272 >> pi@gps ~ $ cat /sys/class/pps/pps0/assert >> 1455835154.690359907#4305 >> pi@gps ~ $ cat /sys/class/pps/pps0/assert >> 1455835157.936493770#4308 >> pi@gps ~ $ cat /sys/class/pps/pps0/assert >> 1455835160.102904599#4310 >> > > Okay so your PPS looks fine. > > I think what's happening (and I'm half guessing but I did the following in > the past to solve the same problem) is that you have two separate refclocks. > One is your GPS NMEA (which is working), and the other is your PPS source ... > which is only providing timing, not time. > > I believe you need to make it so that the PPS refclock is treated as a sort > of extension of the GPS refclock, then prevent the GPS refclock from being > selected on its own: > > refclock SHM 0 refid GPS precision 1e-1 offset 0.9999 delay 0.2 noselect > refclock SOCK /var/run/chrony.ttyAMA0.sock refid PPS lock GPS > > I'm not sure why you see "PP" in the "chronyc sources" output - double-check > your file on disk for dodgy line endings perhaps? Bit of a concern if the > trailing "S" now gets truncated in my example above. > > Anyway, give that a try. > > Cheers > Tom
I have this config working on a RP 2 - different PPP device but substituting your device for mine and adjusting the offsets to suit your device may work. I got this config from the gpsd web site # SHM0 from gpsd is the NEMA data at 4800bps, so is not very accurate refclock SHM 0 precision 1e-1 offset -0.135 delay 0.5 refid NEMA # SHM1 from gpsd (if present) is from the kernel PPS_LDISC # module. It includes PPS and will be accurate to a few ns refclock SHM 1 offset 0.00135 delay 0.1 refid PPS # SOCK protocol also includes PPS data and # it also provides time within a few ns refclock SOCK /var/run/chrony.ttyUSB0.sock offset 0.00135 delay 0.0 refid SOCK Bryan Christianson br...@whatroute.net -- To unsubscribe email chrony-users-requ...@chrony.tuxfamily.org with "unsubscribe" in the subject. For help email chrony-users-requ...@chrony.tuxfamily.org with "help" in the subject. Trouble? Email listmas...@chrony.tuxfamily.org.
