Exploring BeagleBone: Tools and Techniques for Building with Embedded Linux

CHAPTER 8 Interfacing to the BeagleBone Buses

This chapter describes bus communication in detail, explaining and comparing the different bus types that are available on the BeagleBone. It describes how you can configure them for use, and how you can communicate with and control I²C, SPI, and UART devices, using both Linux tools and custom-developed C and C++ code. Practical examples are provided that use a low‐cost accelerometer, a serial shift register, and the Arduino microcontroller. After reading this chapter, you should have the skills necessary to interface the BeagleBone to almost all of its available bus types.

Equipment Required for This Chapter:

• BeagleBone Black (BBB)
• ADXL345 accelerometer on a breakout board
• 74HC595 shift register, LEDs, and resistors
• 3.3 V Arduino microcontroller or 5 V Arduino microcontroller and logic‐level translator

Further details on this equipment and chapter are available at www.exploringbeaglebone.com/chapter8/.

Introduction to Bus Communication

In Chapter 6, the use of GPIOs and analog I/O is discussed in detail, which makes it clear how you can connect the BBB to standalone components. This chapter examines more complex communications that can be performed using the bus interfaces that are available on the BBB. Bus communication is a mechanism that enables data to be transferred between the high‐level components of an embedded platform, using standardized communications protocols. The two most commonly used embedded systems buses ...