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In-depth instruction and practical techniques for building with the BeagleBone embedded Linux platform

Exploring BeagleBone is a hands-on guide to bringing gadgets, gizmos, and robots to life using the popular BeagleBone embedded Linux platform. Comprehensive content and deep detail provide more than just a BeagleBone instruction manual-you´ll also learn the underlying engineering techniques that will allow you to create your own projects. The book begins with a foundational primer on essential skills, and then gradually moves into communication, control, and advanced applications using C/C++, allowing you to learn at your own pace. In addition, the book´s companion website features instructional videos, source code, discussion forums, and more, to ensure that you have everything you need.

The BeagleBone´s small size, high performance, low cost, and extreme adaptability have made it a favorite development platform, and the Linux software base allows for complex yet flexible functionality. The BeagleBone has applications in smart buildings, robot control, environmental sensing, to name a few; and, expansion boards and peripherals dramatically increase the possibilities. Exploring BeagleBone provides a reader-friendly guide to the device, including a crash course in computer engineering. While following step by step, you can:

Get up to speed on embedded Linux, electronics, and programming
Master interfacing electronic circuits, buses and modules, with practical examples
Explore the Internet-connected BeagleBone and the BeagleBone with a display
Apply the BeagleBone to sensing applications, including video and sound
Explore the BeagleBone´s Programmable Real-Time Controllers
Updated to cover the latest Beagle boards, Linux kernel versions, and Linux software releases.
Includes new content on Linux kernel development, the Linux Remote Processor Framework, CAN bus, IoT frameworks, and much more!
Hands-on learning helps ensure that your new skills stay with you, allowing you to design with electronics, modules, or peripherals even beyond the BeagleBone. Insightful guidance and online peer support help you transition from beginner to expert as you master the techniques presented in Exploring BeagleBone, the practical handbook for the popular computing platform.



TABLE OF CONTENTS
Introduction xxix

Part I Beagle Board Basics 1

Chapter 1 The Beagle Hardware Platform 3

Introduction to the Boards 3

Who Should Use the Beagle Platform 6

When to Use Beagle Boards 7

When Should You Not Use the Beagle Boards 7

BeagleBone Documentation 8

The Beagle Hardware 10

BeagleBone Versions 10

The Beagle Hardware 12

Beagle Accessories 19

Highly Recommended Accessories 19

Headers for the PocketBeagle 20

Micro-SD Card (for Booting or Flashing eMMCs) 20

External 5V Power Supply (for Peripherals) 22

Ethernet Cable (for Wired BBB Network Connection) 22

HDMI Cable (for Connection to Monitors/Televisions) 22

USB to Serial UART TTL 3.3 (for Finding Problems) 23

Optional Accessories 24

USB Hub (to Connect Several USB Devices to a USB Host) 25

Micro-HDMI to VGA Adapters (for VGA Video and Sound) 25

Wi-Fi Adapters (for Wireless Networking) 25

USB Webcam (for Capturing Images and Streaming Video) 25

USB Keyboard and Mouse (for General-Purpose Computing) 26

Capes 26

How to Destroy Your Board! 27

Summary 29

Support 29

Chapter 2 Beagle Software 31

Linux on the Beagle Boards 32

Linux Distributions for Beagle Boards 32

Create a Linux Micro-SD Card Image 33

Communicating with the Boards 34

Installing Drivers 34

Wired Network Connections 35

Internet-over-USB (All Boards) 36

Regular Ethernet (BBB and BeagleBoard Only) 39

Ethernet Crossover Cable (BBB and BeagleBoard Only) 40

Communicating with Your Board 42

Serial Connection over USB 42

Serial Connection with the USB-to-TTL 3.3 V Cable 43

Connecting Through Secure Shell 44

Secure Shell Connections Using Putty 45

Chrome Apps: Secure Shell Client 45

Transferring Files Using Putty/psftp over SSH 46

Controlling the Beagle Board 48

Basic Linux Commands 48

First Steps 49

Basic File System Commands 50

Environment Variables 52

Basic File Editing 53

What Time Is It? 54

Package Management 56

Beagle-Specific Commands 58

Expand the File System on an SD Card 59

Update the Kernel 60

Interacting with the On-Board LEDs 61

Shutdown 63

Node.js, Cloud9, and BoneScript 64

Introduction to Node.js 64

Introduction to the Cloud9 IDE 66

Introduction to BoneScript 67

Summary 69

Further Reading 69

Chapter 3 Exploring Embedded Linux Systems 71

Introducing Embedded Linux 72

Advantages and Disadvantages of Embedded Linux 73

Is Linux Open Source and Free? 74

Booting the Beagle Boards 74

Bootloaders 74

Kernel Space and User Space 83

The systemd System and Service Manager 85

Managing Linux Systems 90

The Superuser 90

System Administration 92

The Linux File System 92

Links to Files and Directories 94

Users and Groups 95

File System Permissions 98

The Linux Root Directory 102

Commands for File Systems 103

The Reliability of SD Card/eMMC File Systems 111

Linux Commands 113

Output and Input Redirection (>, >>, and <) 113

Pipes ( and tee) 114

Filter Commands (from sort to xargs) 115

echo and cat 117

diff 118

tar 119

md5sum 120

Linux Processes 121

How to Control Linux Processes 121

Foreground and Background Processes 122

Other Linux Topics 124

Using Git for Version Control 124

A Practice-Based Introduction 126

Cloning a Repository (git clone) 126

Getting the Status (git status) 128

Adding to the Staging Area (git add) 128

Committing to the Local Repository (git commit) 129

Pushing to the Remote Repository (git push) 129

Git Branching 130

Creating a Branch (git branch) 130

Merging a Branch (git merge) 132

Deleting a Branch (git branch -d) 132

Common Git Commands 133

Desktop Virtualization 134

Code for This Book 135

Summary 136

Further Reading 136

Bibliography 137

Chapter 4 Interfacing Electronics 139

Analyzing Your Circuits 140

Digital Multimeter 140

Oscilloscopes 141

Basic Circuit Principles 143

Voltage, Current, Resistance, and Ohm's Law 143

Voltage Division 145

Current Division 146

Implementing Circuits on a Breadboard 147

Digital Multimeters and Breadboards 149

Example Circuit: Voltage Regulation 150

Discrete Components 152

Diodes 152

Light-Emitting Diodes 153

Smoothing and Decoupling Capacitors 156

Transistors 158

Transistors as Switches 159

Field Effect Transistors as Switches 162

Optocouplers/Optoisolators 164

Switches and Buttons 166

Hysteresis 168

Logic Gates 169

Floating Inputs 173

Pull-Up and Pull-Down Resistors 173

Open-Collector and Open-Drain Outputs 174

Intercon