On Wed, Oct 6, 2010 at 09:42 AM, Venu Gopal <[email protected]> wrote: > Hello Folks, > > I tried using time1 and time2 flags but things became worse :-(. > Everything works fine with NMEA driver when using local PPSAPI. > And I don't need use time1 or time2 flags (set to 0 by default).
I believe you are conflating two separate issues. At the time the NMEA driver had its own PPSAPI code, it used a single fudge for both PPSAPI and serial end-of-line timestamp offsets. Since then, the two fudge factors were separated, to allow improved startup behavior by bringing the serial timestamp closer to the PPS that is eventually used. If you are switching back and forth between older and newer ntpd to test using NMEA-local PPSAPI code, you are also switching between the prior and current fudge behaviors. The short-term goal you should have is to experiment with "fudge 127.127.20.x time2 y" varying y to attempt to reduce the size of the step when switching from serial timestamps to PPS. Do this without hardpps, at least initially. You should within a few tries be able to get the difference between the two times in the tens of milliseconds or better. I'm pretty confident others are using the newer NMEA code, sine it has been that way for well over a year. Good luck, Dave Hart _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
