Carey Fisher - NCS

> If you always read from PORTx and always write to LATx, you
> won't get bit by the Read-Modify-Write situation.
> Right?

Well, yes, but note that some instructions
both reads and write to the same FSR in the same
instruction, like BCF/BSF. If you concider those
as "write-only" instructions, then yes. :-)

And, you still might have the case of capacitive loading
on (output) pins that makes the READ from PORTx reading
the wrong state (that is, not what's in LATx). If you
have this rece condition, you might still need the
shadow register to hold a "copy" of your output status.

Jan-Erik.

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