Hello,

I've been having some problems with a 16F877 I have, it simply doesn't =
work.  The program I have it running is trivial for diagnostic purposes, =
just turn on a LED on RB5 with a pull-up resistor.  My tests have shown =
that although RB5 is low, it must be tristated because it cannot sink =
any current.  RB5 (or any other I/O pin for that matter) is incapable of =
going high as well. I have not be able to ascertain much more than that =
about the problem, because the chip behaves the same whether power is =
applied or not!  I have connected 11 and 32 to +5 and 12 and 31 to GND, =
but surprisingly the presence or absence of these connections does not =
seem to have any effect on the output,  which makes me suspicious of the =
fact that the chip is dead.  It is brand new, although I have not used =
it before.  Does anyone have any suggestions?

Thanks,
-Mike

P.S. I am not sure if the caps on the crystal meet the spec exactly, but =
it works fine on a 16F84.

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