Graham asked:

>I'm working on a little PIC project and out of sheer desperation I am
>appealing to you for help!
>
>I've designed a very simple alarm system for my house using the
>PIC16F84, that uses Change on Port B Interrupt to detect whether a door
>or window has opened. It then actuates a relay for an alarm and flickers
>

  Graham:

  In addition to suggestions from Jim, Bob and Zack....

  Does the PIC drive any kind of load other than LEDs? If so, can you
  temporarily disconnect them to see if that has any effect?

  What about unused pins? Do you have any, how are they treated in
  software, and are they terminated?

  Reg Neale