Download Arduino Pinout I2C Gallery. I see on arduino uno there is twice sda and sdl: The 2 first pins side to usb connector are sda/scl according to documentation.

I2c Keypad Hackster Io from hackster.imgix.net

You probably think (as i did and as the guys laying out the pinout once you wire it up correctly, this arduino i2c scanner will let you know you have proper connectivity and the address for the device I2c is an interesting protocol. For both boards they are connected to the correct pins.

Here one arduino will act as master and another one will act as slave.

In this arduino i2c tutorial we will use i2c communication between two arduino boards and send (0 to 127) values to each other by using potentiometer. The arduino uno pinout guide includes information you need about the different pins of the arduino uno microcontroller and their uses: If you did, please share it. Hello there is a lack of clarity on the documentation page for arduino nano regarding pins designated for i2c comms.