In the previous chapter, we saw how to manage an LED within the kernel using the sysfs API; however, this was just a really simple example of kernel programming used to show you how implementing a device driver can be trivial in simple cases. Unfortunately, this technique gets complex very quickly according to the peripheral complexity.

Starting from this chapter, we are going to look in detail at how several computer's peripherals can be connected to our BeagleBone Black, and how we can manage them in order to interact with the environment from the user space. That is, we are going to show you how you can get access to some peripherals by enabling and configuring the correct driver; in this case, we don't have to write a driver from scratch but knowing how a driver works, we can try to correctly use an already written one.

In this chapter, we will present the serial ports, one of the most important peripheral classes a computer can have (at least, a...