One thing I've run into deals with programming, specifically ICSP. The
LVP enable pin is different between the 16f877 and the 18f452. If you
are doing ICSP, regardless of whether or not it is LVP or HVP, you may
run into problems if the LVP enable pin isn't tied low.

This could just be a peculiarity to my circuit, but I think it's
universal.

Josh
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Larry Bradley wrote:
>
> I have a project using a 16F877 - the board is all laid out, etc. I now
> have a couple of 18F452's, which are pin-for-pin compatible with the '877
> as far as pinout is concerned. Are there any potential problems in
> replacing the 877 with a 452? (I know that I have to change the programming
> - that's not an issue - it's just an electrical issue, I think).

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