I2C is an abbreviation for “Inter-Integrated Circuit”. Times have changed, Phillips is now NXP and I2C has become a communication standard that is supported by virtually every major semiconductor manufacturer.

It was originally developed by Phillips in 1982 to allow integrated circuits within television receivers to communicate with one another. I2C is a serial protocol used on a low-speed 2-wire interface. In future articles we will see how we can build our own I2C devices, how to interface a Raspberry Pi and an Arduino using I2C and how to do some advanced I2C configurations, including using multiple masters on one I2C bus. This will be the first of four articles on I2C. We’ll also see how it can be used to exchange information between two Arduinos and how it can be used to allows one Arduino to control another one.

Today we will correct that and learn more about I2C. Although we have used many I2C sensors and displays in previous articles we have not actually looked into how I2C works and how it can be used to communicate between microcontrollers.

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