[ntp:questions] FreeBSD 5.3, Oncore UT+ and PPS

Dennis Spexet spexet at visi.com
Mon Dec 13 03:34:21 UTC 2004

I'm trying to get pps support working on a FreeBSD 5.3 box, and I'm not sure 
if things are working or not.  After installing FreeBSD 5.3, I built and 
installed a kernel with the PPS_SYNC option enabled.  Then I created 
symbolic links from /dev/oncore.serial.0 and /dev/oncore.pps.0 to 

Configuration files are as follows:

/etc/ntp.conf (linked to /etc/ntp/ntp.conf):

driftfile /var/ntp/ntp.drift
server prefer
server time-c.timefreq.bldrdoc.gov
server ntp1.cs.wisc.edu
server ns.nts.umn.edu
enable kernel monitor pps stats
statsdir /var/ntp/
statistics clockstats loopstats
filegen clockstats file clockstats type day enable
filegen loopstats file loopstats type day enable

/etc/ntp.oncore (linked to /etc/ntp/ntp.oncore):

LON   -92 8.73755
LAT   45 57.9901
HT    295 m
DELAY 8 ns

The "rv" command from ntpq displays the following:

ntpq> rv
status=0464 leap_none, sync_uhf_clock, 6 events, event_peer/strat_chg,
version="ntpd 4.2.0-a Thu Nov  4 22:31:34 UTC 2004 (1)",
processor="i386", system="FreeBSD/5.3-RELEASE", leap=00, stratum=1,
precision=-16, rootdelay=0.000, rootdispersion=4.620, peer=19428,
refid=GPS, reftime=c5678acd.3b726703  Sun, Dec 12 2004 21:28:13.232,
poll=4, clock=c5678ad9.6ac2962b  Sun, Dec 12 2004 21:28:25.417, state=3,
offset=0.000, frequency=0.000, jitter=4.247, stability=0.000

And the "ntptime" command displays:

spexet06# ntptime
ntp_gettime() returns code 0 (OK)
  time c5678b0e.0a52ce00  Sun, Dec 12 2004 21:29:18.040, (.040326427),
  maximum error 182516 us, estimated error 16 us, TAI offset 0
ntp_adjtime() returns code 0 (OK)
  modes 0x0 (),
  offset 0.000 us, frequency 0.000 ppm, interval 4 s,
  maximum error 182516 us, estimated error 16 us,
  status 0x2001 (PLL,NANO),
  time constant 0, precision 0.001 us, tolerance 496 ppm,
  pps frequency 0.000 ppm, stability 0.000 ppm, jitter 0.000 us,
  intervals 0, jitter exceeded 0, stability exceeded 0, errors 0.

I used to run ntpd 4.0.99 on Linux.  When I did, PPS support was indicated 
in the output of rv in the status field.  I don't see it here however, nor 
do I see it in the ntptime status field, so I don't know if pps is working 
or not.

Any help would be most appreciated.  It looks like I've almost got it 

-Dennis Spexet, spexet at visi.com

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