> That's a sensible thing to do. Is r-m-w a peculiarity of the PIC ?
> The AVR, for example, is quite different. There's no mention
> of r-m-w with regard to any port operation. In fact you can
> perform two distinct reads of a port - you can either read the
> latches or use the PIN instruction to read the logical values
> present on the pins
>
Most micro's use RMW, the peculiarity with the PIC is that when such an
operation is performed on a PORT, the value read is not that in the data
latch, but rather the values on the pins.  The 18C/18F series fixed this
problem as you can read either the pins or the data latch.

Mike

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