[ntp:questions] Re: How to configure gps/pps with ntp?

Terje Mathisen terje.mathisen at hda.hydro.com
Sun Mar 26 14:36:04 UTC 2006

David J Taylor wrote:
> Richard B. Gilbert wrote:
> []
>> Keep good notes of everything you do.  There is no documentation for
>> configuring the GPS18LVC and you are being requested to write some to
>> help the next guy who needs it.
> I wrote up what I did here:
>   http://www.david-taylor.myby.co.uk/ntp/FreeBSD-GPS-PPS.htm
> and I hope it may be of some help.
> I find the Wiki almost impossible to use, so if someone more skilled than 
> I (or with a different browser?) wants to add that information in they are 
> welcome.
> As I'm not an expert, may I ask:
> - do I also need a line:
>     server prefer
> - I already have:
>     server    mode 1       prefer
>     fudge    time1 0.000  flag3 1  refid PPS

The NMEA driver has at least some PPS logic built-in, initially to 
overcome the default limit on allowable offset between the serial time 
stream and the PPS signal.

Anyway, afair my 18LVC does not use the ATOM driver...


No, I have only configured NMEA plus a single network peer, and it is 
currently rolling along with 1-2 us offset and jitter.


- <Terje.Mathisen at hda.hydro.com>
"almost all programming can be viewed as an exercise in caching"

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