[ntp:questions] Using PPS
david-taylor at blueyonder.co.uk.invalid
Fri Dec 28 12:31:27 UTC 2012
On 28/12/2012 10:00, Joshua Small wrote:
> I've just sorted this out.
> Although I followed the guide I linked mostly, I did read this page regarding "known issues" and used the configure flags recommended there:
> That page has bad advice it appears. After recompiling with the originally recommended flags, I get the desired PPS output on ntpq.
> It does feel like a bug though. Clearly I missed the flags required for both driver 20 and 22 in my configure script. If I put 22 in my ntp.conf, I got an event telling me, and you know it's broken. With driver 20, it said "ok" and never did anything.
> David, I tried alternating 20 and 22, they both work now for me. I didn't do anything special afaik.
Good to hear you're making progress, Josh.
There is information on NTP bugs here:
although you may have to register to file the report:
I'm used to the Windows implementation of NTP, which doesn't have the
same PPS implementation. I guess that the Linux type 20 driver must
call PPS support internally. I used the type 28 ref-clock initially, as
the GPS/PPS source I had talked TSIP (Trimble) protocol over USB (not
serial), and I used gpsd to see that was working, and make it available
as NMEA messages to NTP.
Likely there are many ways of skinning this cat!
More information about the questions