[time-nuts] Metastability (was Brooks Shera)

[Chris Albertson]

On Mon, Mar 25, 2013 at 3:41 PM, Chris Albertson
<albertson.chris at gmail.com> wrote:

>> In normal operation, the counter is clocking back and forth across the 1024 / 24,000,000 boundary. It has to do this for the control loop to "see" anything. Put another way, if it's always 1024 / 24,000,000 the loop does nothing at all.


Yes.  the counter value never should go more than 30 counts away from
1024.  He defines a difference of over 30 as a "glitch" and as I
wrote, if this happens three times he does a reset and toggle a LED.
 I was surprized at how low the threshold is.  30 seems low but
appearenty it almost never goes that far from 1024

Chris Albertson
Redondo Beach, California