[ntp:questions] Re: Please demistify the SHM driver

Piotr Trojanek ptrojane at mion.elka.pw.edu.pl
Wed Sep 24 11:19:41 UTC 2003

In article <ea26a3f3.0309240143.50ec6d6c at posting.google.com>, Paul Croome wrote:
>Well... 4.625 is not a very good value for the jitter of a GPS refclock.
>My GPS (Motorola Oncore) is currently doing:
>     remote           refid      st t when poll reach   delay   offset  jitter
>*GPS_ONCORE(0)   .GPS.            0 l    9   16  377    0.000   -0.069   0.004
>(...more stuff snipped)

Oncore driver use PPSapi, so jitter that you see in 'ntpq -p' is from
PPS signal. if you use only serial code from GPS receiver, don't expect
0.004 jitter.

Piotr Trojanek

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