What is I2C?
I2C (prounouce “eye-square-see”) is a two-wire bidirectional communication interface. It was invented by Philips and they have protected this name. This is why other manufacturers use a different name for the same protocol. Atmel calls I2C “two wire interface” (TWI). Many of you might already be using I2C on their PCs without knowing it. All modern motherboards have an I2C bus to read temperatures, fan speed, information about available memory…. all kind of hardware information. This I2C bus is unfortunately not available on the outside of the PC (there is no physical connector). Therefore we will have to use something else.
