Nick Veys wrote:
>
> Just double checking this.  At 4MHz, the timer will interrupt every:
> 256((2^(prescaler+1)/(2^22)) seconds.  So with a 0 prescalar you'll be
> getting an interrupt every: 256(2/(2^22)) seconds (122us)?  This appears to
> be the smallest obtainable period with this clock speed.  If anyone can
> confirm this, it'd be much appreciated!!
>
> Also, if someone has a better timer interrupt reference than the 16F84 data
> sheet, I'd appreciate that too.  The datasheet merely says 1:2 .. 1:256
> prescalars are available and I only assume that means clock/2^(prescale+1).


Hi Nick, no you can assign the prescaler to WDT,
then the timer0 will inc with every instruction,
ie, 1:1 ratio. It will interrupt on overflow
every 256 instructions.

The 16C84 manual has a lot of data not in the
16F84 or 16F84A datasheets. It has some nice
diagrams about the ints and timer0 int latency.
You can download from this page:

http://www.ezy.net.au/~fastvid/16c84_man.pdf
(right click on link to download it)
-Roman

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