Electronic – Arduino Uno R3: Controlling Tx and Rx LEDs

arduinoatmel

I am currently attempting to control the Arduino Uno's Tx and Rx LEDs.

These are connected to digital pins 0 and 1 respectively, which are AFAIK, PD4 and PD5.

They are held at +5V, so I assumed that they would switch on when PD4,5 were driven low, however this has not proven to be the case.

I would be immensely grateful if anybody could offer a solution.

The schematic I referred to is here: http://arduino.cc/en/uploads/Main/Arduino_Uno_Rev3-schematic.pdf

Best Answer

I have literally just noticed that the Tx and Rx LEDs are controlled by a second microcontroller!

Thought I was writing for the 328, happens that they're controlled by a 16U2 on the board.

Teaches me not to read all the small print.