> What i wish to do is to make sure that the interactions between the caller
> and PIC will end after 2 minutes.
> Watch dog is not that suitable i think, because the user response varies
> through out the whole interactions.
> Timer0 is also not suitable, since it is in the form of interrupt. my last
> resort will be to use an external timer, any
> ideas?

It sounds like timer 0 does what you want.  Even with the maximum prescaler
you won't get 2 minutes.  You have to count overflows in software to get to
2 minutes.  I don't understand your reason about it using interrupts.


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, olin@embedinc.com, http://www.embedinc.com

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics