"Interrupt on RB0 of P16F877"

I have setup an external interrupt on RB0 of
P16F877-20P. On the rising edge, the controller
entered the interrupt service routine, but exited the
routine automatically after half a sencond without any
changes of the external condition.

Only the external interrupt was enabled, and the
oscillator is runing at 11MHz.

My questions are
1. Did anyone else have the similar problem?
2. Did I set it up wrong?
3. How do I fix it?

Thanks,

YUB

__________________________________________________
Do You Yahoo!?
Yahoo! Sports - live college hoops coverage
http://sports.yahoo.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