user15677: I have read some conflicting sources about what pins have internal pullup resistors available for the Attiny85 microcontroller. Can all I/O pins work with INPUT_PULLUP, or just some of them? And if so, which ones?
Thanks!

user8033: Check the datasheet, probably just search for "internal" or "pullup"  I believe there are little more pins/ports as portB, so they should all have internal pull ups.

15677: <p>I have read some conflicting sources about what pins have internal pullup resistors available for the Attiny85 microcontroller. Can all I/O pins work with INPUT_PULLUP, or just some of them? And if so, which ones?</p>

<p>Thanks!</p>
 8033: <p>Check the datasheet, probably just search for "internal" or "pullup" <img src="https://i.stack.imgur.com/KnmyK.jpg" alt="enter image description here"> I believe there are little more pins/ports as portB, so they should all have internal pull ups.</p>
