Mohamed Othman

Unused pins for HCS12 DP512

Discussion created by Mohamed Othman on Apr 25, 2007
Latest reply on May 3, 2007 by Alban Rampon
I have question regarding the unused pins.
Since there are internal pull up resistors for most of the pins (core and PIM pins),
do I have to connect an external pull up resistor to those that already have internal one?
(the Application notes recommend to connect every unused port to one pull up resistor).
for the PORT E pins, I am not using any of them (exccpt MODA,MODB), should I connect those also
to an external pullup resistor (although they already have one)?
and what about the TEST pin?
one more thing please,
when we connect an internal pullup resistor to a pin and read it's state, it's not one. is that
why we have to connect an external pull up resistor?

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