Andre: You have it slightly backwards. The portb pull-up does *not* turn the
port into an open-collector type. The output is push-pull whether the
pull-up is enabled or not. The portb pullup is useful when the port is
configured as an input. You would enable the pullup when the device you have
attached to the port is itself open collector (for example, a comparator.)
Does this answer your question?

Brian

-----Original Message-----
From: Andre Abelian <andre@compufire.com>
To: PICLIST@MITVMA.MIT.EDU <PICLIST@MITVMA.MIT.EDU>
Date: Tuesday, December 16, 1997 7:04 PM
Subject: portb pull-up


>Hi to all engineers.
>I am currently working on pic16c62a.
>I know portb has optional pull-up resistors to turn on and off and
>default is on
>but what I do not know what if you make portb as input then what
>happens? do we still have pull-up on or it is only
>for output to make open collector.
>
>Andre                                            thank you
>