>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.

But, generally, in fact most of the time, if I'm reading PORTx I don't care
what's in LATx since I'm using the port as an input, no?
Carey

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