Can tx and rx pins on the uno be used like regular digital pins?

Question

The uno has digital pins marked 0-13.

0 is marked as rx and 1 is marked as tx. Can these two pins be used as regular digital pins if i am short of digital pins?

If you are short of digital pins you can aways use the analog pins. They also work as digital pins. — Mikael Patel, May 15 '18 at 15:44

jfpoilpret · Accepted Answer · 2014-08-13T20:43:47.370

11

Yes you can perfectly use these 2 pins as long as your program does not use Serial.

EDIT: Serial data over USB goes through copper traces connected to the rx and tx pins, connecting them to the USB to serial converter chip.

edited Aug 13 '14 at 20:43

answered Aug 13 '14 at 20:20

jfpoilpret

My program is using serial, but pumping it through the usb. Not out of the rxtx pins. Is this still a problem? – c_breeez Aug 13 '14 at 20:37
4

It is the same: USB data is passing through RX/TX pins :-( – jfpoilpret Aug 13 '14 at 20:39
Ok thanks for your great answer and clarifying these points – c_breeez Aug 13 '14 at 21:06

score 3 · Answer 2 · answered Aug 21 '14 at 14:49

3

Also you will probably want to ensure these wires are not connected when programming the Arduino. Otherwise you may have problems.

answered Aug 21 '14 at 14:49

sdcharle

score -1 · Answer 3 · answered May 14 '18 at 01:28

-1

You can, but it will disable the serial port.

answered May 14 '18 at 01:28

BobTheAverage

1

No, it's the other way around: the serial port has higher priority. When you enable it with `Serial.begin()`, you are disabling the normal port operation (`pinMode()`, `digitalRead()` and `digitalWrite()`). With one exception: you can set the RX pin to `INPUT_PULLUP`, rather than `INPUT`, which is the default. C.f. the datasheet of the ATmega328P, especially the sections _Alternate Port Functions_, _Data Transmission – The USART Transmitter_ and _Data Reception – The USART Receiver_. – Edgar Bonet May 14 '18 at 07:57

3 Answers3