[time-nuts] Tidbit for Soekris 4501 NTP users
John Ackermann N8UR
jra at febo.com
Sun Aug 19 18:15:09 UTC 2012
This is probably something that very, very few other people are going to
encounter, but thought I would note it here for posterity.
I'm using the Soekris 4501 with high-resolution Elan CPU for nanosecond
timestamps as documented at http://www.febo.com/pages/soekris. When
using a PPS-only refclock (e.g., pulse from a cesium clock with no
serial timecode), I found that the PPS signal was not being seen unless
some other process held the serial port open.
In the non-time-nuts (or even semi-time-nuts) world, you'd never see
this because the PPS is always associated with a GPS or other device
that is sending a serial timecode. But with a PPS-only setup (where the
prefer peer is a remote host), the symptom is that the PPS source is
The simple cure is to do "cat /dev/pps0 > /dev/null &" as part of the
startup script. There's probably a more elegant way, though.
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