Dear Jawed,

You can impliment a timer by simply writing a couple of nested counting
routines, to "spend" the CPU's time. The general format would be as
follows:

        set initial variable1

        ww:     set initial variable2
        qq:     subtract 1 from variable2
                is it zero?
                if not go to qq

        subtract 1 from variable1
        is it zero?
        if not go to ww


You could add sufficent number of such routines to get a desired basic unit
of measurement , say 1second. You can then multiply by nesting more
routines.

Another possibility is to slow down the clock to absolute low. However that
will effect the other processes that way.

However because of the limited resources of the PICS, please don't expect
to make a timer which is able to span a large period (from seconds to
hours). For that you would need to add external hardware.

Regards
Aurangzeb Haque

----------
> From: Jawed Mateen <jawedm@PAKNET3.PTC.PK>
> To: PICLIST@MITVMA.MIT.EDU
> Subject: PIC TIMER
> Date: Friday, April 24, 1998 8:49 AM
>
> Dear fellows,
>                 I  have just started learning PIC Controllers.I want to
> make a Timer Circuit  0 to 60 minute adjustable.Can anybody help me?
>
> Jawed Mateen
>
> <jawedm@paknet3.ptc.pk>