[ntp:questions] proprietary hardware clock as NTP reference source

Rob Neal hundoj at comcast.net
Sun Jun 13 04:21:58 UTC 2010

On Fri, Jun 11, 2010 at 02:26:13PM -0700, apobrien wrote:
> Hello list,
> I have a set of proprietary hardware timing cards (Symmetricom
> bc635PCIe) which synchronize their clocks using a dedicated
> interconnect.  As you might imagine the timing card conditioned time
> drifts from that of the hosts they're installed in.
> What I'd like to do is make the "master" timing card's time into a NTP
> reference clock then use NTP to distribute that time to the other
> hosts in the (private) network.
> I've looked at Orphan mode and undisciplined local clocks but they
> only refer to the host's software clock if I'm not mistaken.  I've
> also searched through the archive but I'm afraid I lack the
> appropriate terminology to get meaningful results.
> Can someone point me toward (some google words maybe) creating an
> arbitrary NTP reference source (under Linux)?  I think I'm just
> missing something very basic.
> I've been looking at the LinuxPPS project as these cards output a PPS
> that I might use to condition the host clock using Linux PPS but I
> don't have a 8250 serial port on these new fangled PCs.
> TIA!
> Andy
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Symmetricomm has a kernel mode driver for the bc635/7 cards, for Linux. 
If you have a copy you can use ntp reference clock 22 (bancomm) to 
feed the time to NTP

refclock 127.127.16.u mode 2 
	in the config file, where u is whatever unit your card presents as. 

The Symmetricom driver is proprietary, they charge for it, btw. 

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