Tony.N wrote:
..........
>I guess it comes down to a bit of common sense. Xtal speed VS pin
>capactiance, and because writes followed by reads take less than a clock
>cycle for the data recognition, probably closer to a Q cycle, I guess
>the NOP helps a bit - but as you mention not in every case :-)
........


Yeah, you have to trade the NOP time [eie, xtal value] off against
"exactly" what is hanging off the port. I really don't think the
implications of what is going on here are all that "obvious".

Just for the heck of it, I checked the piclist archives, and found
171 msgs related to read-modify-write in the past year or so. I
think it really is fairly easy to get burned by this - and I'll
bet most people here have fallen into the trap at least once.

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics