Hello Bob,

>A typical circuit uses two resistors in series and adds silicon diodes
>to clamp the junction of the resistors to Gnd and Vdd, thus limiting that
>junction to the range Vss-0.6 to Vdd+0.6 or so. This is _still_ out of
>specification for the PIC pin!

in this case you have cascaded R-2D, R-2D (the second 2D inside the chip),
so the second R has limit only 0.3V from 0.6V at the first stage. If this
isn't o.k. you can still choose schottky. But the questions should be :
which voltage are you protecting the pins from? Depending on the answer, you
should go different ways.

Andrej


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