SDA SCL I2C TWI Pins on the Arduino

This post details where the SDA SCL pins used for I2C/TWI are available on Arduino’s.

I2C TWI pins on the Arduino

The SDA and SCL pins are the used for communication using the I2C/TWI protocols. These allow multiple devices to communicate the Arduino on a standard interface.

Most Arduino’s only have one set of these pins however the Due has two.

For more information, you can read the Arduino page on the Wire library.