Why do you say that it should be "0"?  In general though,
you should not leave the inputs floating, cause the value
seen at the port will be unpredictable, though I've found
that it tends to assume the "1" state most of the time.

You should explicitly set it to the default you want with
pull-up or -down resistors (you can use the PIC built-in
weak pull-ups).  Generally I keep the weak pull-ups on and
switch to ground, so the processor sees "1" until the switch
is pressed.

Cheers,
-Neil.



> -----Original Message-----
> From: pic microcontroller discussion list
> [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of guy
> Sent: Sunday, August 25, 2002 2:44 PM
> To: PICLIST@MITVMA.MIT.EDU
> Subject: keypad
>
>
> apology for those who received this earlier!
>
> Hi All,
>
> I recently made a pcb of 8x8 keypad with two "E"s facing eachother at each
> keypad
> point.  Somehow, the port always gives value when it is
> supposed to be "0" since there is no keypress.  Is this a capacitance or
> resistance problem?  any help greatly appreciated.
>
>
> Yansong
>
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>

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