Micro Eng wrote:

> switching gears to a diff project....
>
> I am using a 4.9152MHz crystal, and part of what I need to do is do some
> timing delays like 30 seconds, 1 hour, a day and 30 days.
>
> So I figured the easiest way is to have registers that decremented for
> minute, for hour, for day, etc.
>
> HOWEVER....looking at the prescaler values for say TMR0, if I use this
> crystal (that someone else said...use this and it will work fine) each
> state
> cycle is .813uS (approx) and if I use the 1:256 prescale I get
> 208.33mS for
> each tic for TMR0 and since its just an 8bit value, I can't get one
> second,
> best I can get is 1/32 of a second.

Setting TMR0 to count 240 gets you a nice round 50 mS.
Every 20 of these is a second....

> And of course thats fine, I get the
> TMR0 interupt and dec a register,etc.  Now also someone mentioned to me
> about using the CCP but I don't quite follow how that might help

Since you didn't mention which PIC....
No comment.

>
>
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--
  *
  |  __O    Thomas C. Sefranek  tcs@cmcorp.com
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