At 1:05 AM 1/29/97, Scott Reynolds wrote:
>On Tue, 28 Jan 1997, Christopher R. Bowman wrote:
>> So what we want to do is monkey with the variable that we add to the system
>> clock so that the RTC time which is relatively stable but of poor
>> resolution, and the system time which is of better resolution but not so
>> good stability converge.  Kinda like a phase locked loop.
>
>Well, there's a third option, if someone wants to take a look at it.
>
>There is a 1Hz interrupt on VIA1 on all of the machines listed in the
>GMFH.  Setting it up properly should be pretty trivial.  I suspect we
>could harness this interrupt to discipline the clock, as it's far less
>likely to be lost...  any takers?
>

Just my $.02:  What you guys are talking about is basically NTP with a 1PPS
time reference derived from the VIA1.  It sounds pretty easy in theory.

Since NTP tries to compute a drift rate for the system clock and the drift
isn't constant it won't work *well* without some nonstandard tuning IMHO.

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