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Is a 12f output pin an open drain?

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New Member
I just saw a post that stated when a PIC pin is in output mode it's an open drain? Is this true of all the 8-bit series? I think the post was about the 16f or 18f specifically, but I was wondering about the 12f? I can't seem to find it now. :(

Nigel Goodwin

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Most Helpful Member
It's usually RA4 - which of course doesn't apply to 12F series.

The datasheet will tell you if there is one, on any PIC.

BTW - you can get exactly the same (as far as 5V levels go) on any PIC I/O pin, by setting the pin LOW and switching TRIS to input and output - my I2C routines work like that, as do most.
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Well-Known Member
For PIC12F629 and 675 (and possibly others) GP3 (pin4) is input only. In all my projects, I use this pin for inputs such as a switch. It needs an external resistor to achieve "pin change."
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