Robin Abbott wrote:
> I am surprised by the blowing of the chip on 12V applied to MCLR

You shouldn't be.  This is very clearly spelled out in the datasheet right
where you'd look for it.  The third line down under Absolute Maximum Rating=
s
specifies -300mV to 6V as the range.  Since 12V > 6V, there should be no
surprise that it goes poof at 12V.

> as all inputs are protected by static protection diodes which can
> usually handle several mA which is below the current limit of most
> programmers.

So let me get this straight.  You guess how the circuitry is implemented,
and based on that guess, you decide you know better than the PIC designers
and that the absolute maximum limits published in the datasheet are wrong!!=
?
I won't bother explain then what is wrong with your guess since I expect to
have even less credibility than the datasheet.

Or if I got this wrong I apologize, but then please do show us a copy of
your personal exemption certificate for being allowed to violate the laws o=
f
physics.


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