[time-nuts] 5370 processor boards available

Hal Murray hmurray at megapathdsl.net
Wed Oct 8 18:16:34 EDT 2014


jks at jks.com said:
> I made a real mistake by not running the 5370's 10 MHz oven clock, that was
> available right there on a processor board pin, to a GPIO on the Beagle so
> it could be accurately counted with the built-in event counter and software
> overflow (that clock used to drive the processor clock of the old MC6800). A
> terminating resistor and level-shift are required if I remember correctly,
> so it would be slightly more effort than a "blue wire" fix. 

Another option would be to connect it to the clock-in pin so the CPU runs in 
lock step with a good clock.

I'm assuming there is a PLL inside the chip so the exact value of the 
external clock doesn't matter as long as you are willing to patch the 
software that sets up the PLL.


-- 
These are my opinions.  I hate spam.





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