I usually setup a pic I know that's working with a simple program like
this:

movlw 0
tris PORTA
tris PORTB
CLRF PORTA
CLRF PORTB

MOVLW b'11111111'
MOVWF PORTA
MOVWF PORTB

loop
goto loop

Now when you try a working pic attach 1led to any pin on porta and
portb.  The working pic should light up each.  A dead pic won't.

For some reason if you do something odd to a pin the whole port tends to
go on the pic.  No idea why.  Anyone?  But usually if one port goes the
other is ok.

This sounds like your problem as pics can still be programed when a port
is blown.  I think this is because the i/o section is blown but I think
there is an internal multiplexer that still allows programing.

Hope this helps,
Aaron

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