Vicent Colomar Prats wrote:
> But I maintain that I prefer to protec
> unused pins thru limiting resistors against leaving them unconnected
> or tied to Vcc/Gnd.

This makes no sense.  Protect against what?  What are the resistors supposed
to limit, considering these are unconnected pins in the first place?  And
it's not clear what is supposed to be on the other end of those resistors
from the PIC pin.  If you are leaving them open, then all you've done is add
antennas to the unused pins, with a little extra capacitance to unknown
parts of the circuit.

There are some legitimate reasons for pullup or pulldown resistors on unused
pins as I also mentioned in my first post on this thread, but "protection"
and "limiting" aren't included in these reasons.  Setting unused pins to
outputs and driving them low essentially connects them to ground via a few
10s of ohms.  Given that, a otherwise unconnected PIC pin is going to be
about as safe as it gets.  If something can get in there to hurt it, the
rest of the circuit is in serious trouble.


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