Quintin Beukes wrote:

> It's night time at the moment. I had a look at one of the circuits we
> do have (which is working fine), but it's MCLR is not even connected,

Then (if the PIC is configured using "internal MCLR") RA3 is an input
and should probably be connected to *something* (pullup/pulldown).

Have you tried to stress that circuit ? Like pointing/touching
the MCLR/RA3 pin with your finger ?

Now, if one do not *need* that extra input pin (RA3), there is
little reason to not use it as a regular MCLR pin. No matter
how the pin is CONFIG'ed, it should not be left "open" anyway.


-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist