Now we are ready to manage the real I²C devices. We can find tons of supported devices in the Linux kernel tree, which are usually grouped according to their specific operations; so, for instance, all the I²C real-time clock chips are under the drivers/rtc/ directory, while the I²C EEPROMs are under the drivers/misc/eeprom/ directory, and so on.

For example, we're going to use the following development board that carries five I²C devices:

On this board, we have an EEPROM, an ADC, a DAC, a temperature sensor, and an I/O expander, so it's perfect to show you how the I²C bus works, and how the preceding device classes can be accessed within our BeagleBone Black.

First of all, we must complete the electrical connections; so, in the following table, I reported the connection between the BeagleBone Black's pins and the I²C developing board's pins: