Richard R. Pope wrote 2014-07-21 06:42:
> Allen,
> I understand that I am not resetting the timer and because of this
> the first 100ms can actually be anywhere from 1ms to 99ms off. This can
> cause anywhere from a 1 to 10% error rate. I thought of this while I was
> half a sleep and half a wake yesterday.

>  I don't understand how to call the interrupt routine...

*You* never do. It is "called" automaticly by the interrupt
hardware logic whenever an interrupt condition occures.


> and how to reset the timer.

TMR1H =3D 0x0B;
TMR1L =3D 0xDC;

This can be done somewhere from your main() code (or in any
function called from main() ). It makes the timer start
on a new full 0.1 sec period.

> I'm resetting the
> count variable in the for loop. I am also checking for the counter
> reaching 10 which is 1 second of time in the for loop. The incrementing
> of count is taking place in the interrupt routine. So I guess my next
> step is how do I actually use the interrupt routine?

If you have setup the interrupt logic (GIE, TMR1IF and so on),
the interrupt routine *will* be used whenever the timer1
rolls over (FFFF -> 0000).

> This routine:
>
> Do I call Interrupt()?
>

No, never. See above.

>    void Interrupt()
>             {
>                 if (TMR1IF_bit)
>                     {
>                          TMR1IF_bit =3D 0;
>                          TMR1H =3D 0x0B;
>                          TMR1L =3D 0xDC;
>                          If so, what do I put here?
> 		       count++; //This increments the count variable
> which was declared as global.
>                     }
>              }
>
> Thanks,
> rich!
>
> On 7/20/2014 4:14 PM, Allen Mulvey wrote:
>> The for loop doesn't need to increment the counter. The ISR is doing tha=
t in
>> the background. I just think more conventional coding is easier to follo=
w
>> and most compilers will probably produce the same code for either. (I
>> haven't tested this theory but past experience would cause me to be
>> surprised if it didn't..)
>>
>> Allen
>>
>>
>
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