The subtle problem of being able to set the state of a OUTPUT
pin by noise which may occur during a Read/Modify/Write to another
pin in the same port, is worth emphasising again (periodically)
so any 'newbies' don't get 'bit' by it as many of us have at
OUR time. I notice one (at least, ...) 'unmentionable' <G.>chipmaker
now adds another register to the port logic to try to avoid this.

Maybe we could all stop politic-ing long enough to but together
a 'gotchas' list. We could co-locate it with the PICList Archive.

R.Martin

"Randy A." wrote:

> As for myself, and I have been designing and fabricating electronic circuits
> for over 20 years, I wouldn't attempt to interface the Inputs and Outputs of
> ANY micro-controller or microprocessor directly to the outside world.  That
> would violate every precaution I was ever taught plus it is just plain common
> sense.  The very very minute cost of either diodes, transistors, or buffers
> ICs is just not worth destroying your project.
>
> Well, again that is my $.02 worth on the subject, nuf said by me.
>
> Randy A.