Download Arduino Uno I2C Pins Background. Pin a4 is the sda pin, and pin a5 is the scl pin. 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.

Introduction To Arduino Nano The Engineering Projects
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The 2 first pins side to usb connector are sda/scl according to documentation. The arduino uno pinout guide includes information you need about the different pins of the arduino uno microcontroller and their uses: The image below shows the i2c pins present in arduino uno.

With i2c there are 2 wires referred to as scl and sda.

In the arduino uno r3 version, there is another set of i2c pins near the usb socket: The 2 first pins side to usb connector are sda/scl according to documentation. To build this project, you'll need the following parts As a reference the table below shows where twi pins are located on various arduino boards.