[Arduino UNO] How to disable pullup resistor ??

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1

Hi all!

Simple question, simple answer, i hope.
I'm using an Arduino Uno, and i'd like to globaly disable pullup resistors. How do I do that?

Thanks in advance.

2

Are you asking how to disable the internal pull-up resistors?

3

If you want to disable ALL internal pullups:

MCUSR |= _BV(PUD);

To enable again:

MCUSR &= ~_BV(PUD);

If they are external pullups, instead of connecting them to +5v, connect them all to one of the Arduino pins and use digitalWrite() to control them.

4

Guilhaz:
Hi all!

Simple question, simple answer, i hope.
I'm using an Arduino Uno, and i'd like to globaly disable pullup resistors. How do I do that?

Thanks in advance.

Unusual request as all input pin pull-ups are disabled at reset or power up. Any pull-ups you do enable should be easy to keep track of if you indeed need to disable them for some reason.

So why do you think you need this?

5

I got what I need! Thanks everyone

6

Guilhaz:
I got what I need! Thanks everyone

how did you do it @guilhaz?
i am having problems disabling the internal pull up resistors.

thank you

7

llexer:
how did you do it @guilhaz? i am having problems disabling the internal pull up resistors.

RTFM?

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