Moses McKnight wrote:

> Unless I pull the pin low before I change it to an input the
> line stays high.

Never design anything like that.

> - I guess due to the board traces and maybe the switch
> acting as a capacitor and storing a charge.

Or, in other words, "undefined", which is the last
thing you want, right ? :-)

> What did you mean by open inputs?  A pin tied to
 > nothing and set as an input?

Yes!
Never, ever do that !
The pin will pick up electromagnetic "noice" from the
environment and act as a 50 (or 60) Hz generator and
create all sorts of non-wanted effects.

So, *never* leave an CMOS input pin un-connected.
This is true for *any* CMOS circuit, not only
PICs and not only microcontrollers.

Well, besides those IC where the data sheet clearly
says that there are internal pull up/down restors,
of course. But that's a special case...

Jan-Erik.
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