At 09:11 PM 5/3/2005, Jinx wrote:
> > 13.15usec per half cycle.  I don't think you have enough time to
> > save and restore context and reload timer0 at 4MHz, let alone
> > keep track of other timing.
>
>Maybe put a 32kHz xtal on Timer1 and use that to measure the
>5 & 20 second intervals (T1 OSC available only if you use the
>internal osc), keeping TMR0 @ 4MHz just for the 38kHz

Close - so close.

How about putting a 38KHz crystal on TMR1, then turn it on and off as 
needed?  Those 38 KHz crystals are darned cheap - even from Digikey - and 
you have all the other resources of the '675 available for use.

dwayne

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Dwayne Reid   <dwayner@planet.eon.net>
Trinity Electronics Systems Ltd    Edmonton, AB, CANADA
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