Hmmm, well I guess it depends on which PIC you are looking at.
manumenzella never specified. And the original post regarding RA4 as much as assumed they are ALL like that.

Paul was referencing the 16F628, which according to the most recent datasheet, Has the diode.

If you look at a 16F628A, then it doesn't.

If you look at the 18F452 datasheet from a couple years ago, it says it does, but the most recent one doesn't.
Was it a change in the datasheet, or the silicon?

Like my original comment,
"Which one are we supposed to believe?"

Personally, I'd go with the transistor.
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