[time-nuts] 1PPS to 32.768 khz

Hal Murray hmurray at megapathdsl.net
Wed Oct 19 22:26:19 EDT 2016

> Here's another way to do it for a wall clock display...   set up an
> oscillator/divider (or even a 555 timer) to generate a frequency close to,
> but faster than 65536 Hz.    Setup a 16 bit counter clocked by that signal.
> When the 1PPS signal arrives, start the counter.  After 65536 pulses the
> counter will overflow... stop the counter (and set up for the next 1PPS
> trigger) when that happens.   The Q0 output (lowest bit) from the counter
> will be a burst of 32768 pulses that repeats once a second.  Use that to
> drive your clock.   The slight pause between bursts of 32768 pulses will not
> be noticed on the clock display. 

Neat hack.  Thanks.

You can do it with a tiny micro.  Some of them come with builtin R-C 
oscillators so the parts count would be really low.

These are my opinions.  I hate spam.

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