Programming the BeagleBone

Yogesh Chavan

• Publisher: Packt Publishing
• Year: 2016
• ISBN:
  9781784399030
• Edition: 1
• Topic: Computer Science
• Subtopic: Hardware
• Index: Computer Science

Master BeagleBone programming by doing simple electronics and Internet of Things projectsAbout This Book• Quickly develop electronics projects that interact with Internet applications using JavaScript and Python• Learn about electronics components such as sensors and motors, and how to communicate with them by writing programs• A step-by-step guide to explore the exciting world of BeagleBone—from connecting BeagleBone to doing electronics projects and creating IoT applicationsWho This Book Is ForIf you want to learn programming on embedded systems with BeagleBone by doing simple electronics projects, this book is for you. This book is also helpful to BeagleBone owners who want to quickly implement small-scale home automation solutions. It is assumed that you have familiarity with C and Python programming. Some familiarity with electronics is helpful but not essential.What You Will Learn• Connect your BeagleBone to a computer in different ways and get the Cloud9 IDE running to quick-start programming on the BeagleBone• Get to know about BeagleBone extension pins such as GPIO and how to connect various electronics components with BeagleBone• Read and write to various electronics components such as LED, Push-button, sensors, and motors• Grasp in-depth theory on Analog, PWM, and BUS programming and the electronics components used in programs• Handle data to and from various BUS supporting modules such as UART, I2C, and SPI using the Adafruit BBIO Python library• Write real-life IoT applications in JavaScript and Python such as shooting an e-mail on overheat and controlling a servo motor remotely• Make use of online free cloud services to store and analyze sensor data collected on the BeagleBone• Discover what else can be done using the BeagleBone• Get to grips with embedded system BUS communicationIn DetailThe whole world is moving from desktop computers to smartphones and embedded systems. We are moving towards utilizing Internet of Things (IoT). An exponential rise in the demand for embedded systems and programming in the last few years is driving programmers to use embedded development boards such as Beaglebone.BeagleBone is an ultra-small, cost-effective computer that comes with a powerful hardware. It runs a full-fledged Debian Linux OS and provides numerous electronics solutions. BeagleBone is open source and comes with an Ethernet port, which allows you to deploy IoT projects without any additions to the board. It provides plenty of GPIO, Anlaog pins, and UART, I2C, SPI pins which makes it the right choice to perform electronics projects. This gives you all the benefits of Linux kernel such as multitasking, multiusers, and extensive device driver support. This allows you to do programming in many languages including high-level languages such as JavaScript and Python.This book aims to exploit the hardware and software capabilities of BeagleBone to create real-life electronics and IoT applications quickly. It is divided into two parts. The first part covers JavaScript programs. The second part provides electronics projects and IoT applications in Python.First, you will learn to use BeagleBone as tool to write useful applications on embedded systems. Starting with the basics needed to set up BeagleBone and the Cloud9 IDE, this book covers interfacing with various electronics components via simple programs. The electronics theory related to these components is then explained in depth before you use them in a program. Finally, the book helps you create some real-life IoT applications.Style and approachAn easy-to-follow guide full of real-world electronics programs and quick troubleshooting tips using BeagleBone. All the required electronics concepts are explained in detail before using them in a program and all programs are explained in depth. Most of the theory is covered in the first part; while the second part gives you some quick programs.

Programming the BeagleBone

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Table of Contents

Programming the BeagleBone

Credits

About the Author

Acknowledgment

About the Reviewers

www.PacktPub.com

Support files, eBooks, discount offers, and more

Why subscribe?

Free access for Packt account holders

Preface

What this book covers

What you need for this book

Who this book is for

Conventions

Reader feedback

Customer support

Downloading the example code

Downloading the color images of this book

Errata

Piracy

Questions

1. Cloud9 IDE

BeagleBone hardware

BeagleBone White (BBW)

BeagleBone Black (BBB)

BeagleBone Green (BBG)

Installing Debian image on SD card

Setting up BeagleBone

Direct connection to monitor and keyboard

Ethernet over USB

Troubleshooting

Ethernet port or USB Wi-Fi adapter

Troubleshooting

VNC

Troubleshooting

Serial Connection

The bone101 page

Cloud9 IDE

Hello World program

Explanation

Summary

2. Blinking Onboard LEDs

Digital I/O

Digital I/O functions - pinMode() and digitalWrite()

Program to turn onboard LED ON and OFF

Program explanation

Quick program to blink onboard LED

Program explanation

Program execution

Make our program better

Program explanation

Dancing LEDs

Program explanation

Dancing LEDs in both directions

Program explanation

Summary

3. Blinking External LEDs

What is GPIO?

BeagleBone GPIO map

Blinking external LED circuit setup

Circuit analysis

Program to blink external LED

Explanation

Troubleshooting

Dancing external LEDs circuit setup

Circuit analysis

Program to dance external LEDs in both directions

Explanation

Summary

4. Controlling LED Using a Push Button

Reading from digital components

Push button circuit setup

Circuit analysis

Program to read from push button

Explanation

Reading via interrupts

Push button LED circuit setup

Circuit analysis

Program to control LED by push button

Explanation

Summary

5. Reading from Analog Sensors

Analog I/O

Reading from analog components

TMP36 temperature sensor circuit setup

Circuit analysis

Program to print temperature

Explanation

LDR circuit setup

Circuit analysis

Program to check light intensity

Explanation

Summary

6. PWM – Writing Analog Information

What is PWM?

BeagleBone's PWM

Writing on analog components

Fading LED circuit setup

Program to fade in and fade out LED

Explanation

Micro servo motor circuit setup

Program to control a micro servo motor

Explanation

Summary

7. Internet of Things with BeagleBone

Why the Internet of Things?

What is the Internet of Things?

Program for creating new Node.js HTTP server

HTML code

JavaScript code

Explanation

Troubleshooting

Program to control an LED through web browser

HTML code

Explanation

JavaScript code

Explanation

Controlling a servo motor through LAN

HTML code

JavaScript code

Sending an e-mail on over-temperature

Explanation

Troubleshooting

What's next?

Summary

8. Physical Computing in Python

Python programming in BeagleBone

Adafruit BBIO library

Program to blink external LEDs

Explanation

Program to dance external LEDs

Explanation

Program to read from push button

Explanation

Detecting button state using interrupt

Explanation

Program to print temperature

Explanation

A Program to check light intensity

Explanation

Program to fade in and fade out LED

Explanation

Program to control micro servo motor

Explanation

Summary

9. UART, I2C, and SPI Programming

Bus and bus protocols

What is UART?

Program to read/write on UART

Explanation

Troubleshooting

I2C protocol

Program to read from ADXL345 sensor

Explanation

Troubleshooting

SPI protocol

Program to write display text on Nokia 5110 LCD

Explanation

Summary

10. Internet of Things using Python

Flask web application framework

Installation

A program to display temperature remotely

Explanation

Troubleshooting

A program to control an LED through a web browser

Explanation

A RESTful web app to control servo motor

Explanation

A program to trigger an e-mail alert on over-temperature

Explanation

Troubleshooting

Upload server data on cloud and visualize

Explanation

What's next?

Security

Summary

A. GPIO Control in Bash

Explanation

Troubleshooting

B. BeagleBone Capes

C. Pinmux and the Device Tree

What is Pinmux?

What is the device tree?

Index

Programming the BeagleBone

Copyright © 2016 Packt Publishing

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews.

Every effort has been made in the preparation of this book to ensure the accuracy of the information presented. However, the information contained in this book is sold without warranty, either express or implied. Neither the author, nor Packt Publishing, and its dealers and distributors will be held liable for any damages caused or alleged to be caused directly or indirectly by this book.

Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals. However, Packt Publishing cannot guarantee the accuracy of this information.

First published: January 2016

Production reference: 1220116

Published by Packt Publishing Ltd.

Livery Place

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Birmingham B3 2PB, UK.

ISBN 978-1-78439-001-3

www.packtpub.com

Cover image by Mr. Vipin Vikam (Silver photo studio, near Kasba Ganpati, Pune)

Credits

Author

Yogesh Chavan

Reviewers

Juan Cortez

Chris Desjardins

Michael Hirsch

Pavel Mamontov

Commissioning Editor

Amarabha Banerjee

Acquisition Editor

Kevin Colaco

Content Development Editor

Susmita Sabat

Technical Editor

Pranil Pathare

Copy Editor

Ting Baker

Project Coordinator

Milton Dsouza

Proofreader

Safis Editing

Indexer

Mariammal Chettiyar

Production Coordinator

Arvindkumar Gupta

Cover Work

Arvindkumar Gupta

About the Author

Yogesh Chavan is a Linux enthusiast and open source promoter, living in Pune, India. He has now been teaching operating systems, device drivers, and embedded systems in colleges and institutes for more than three years. These include the computer science department of Pune University, Symbiosis Institute of Computer Studies and Research (SICSR) college, and the Centre for Development of Advanced Computing (C-DAC) institute. He has about six years of experience in the software industry. His previous industrial role was of a software maintenance engineer at Red Hat Software Services.

Yogesh has overseen many engineering projects under GEEP (http://www.geeksofpune.in). He has given many talks at the annual open source event, GNUnify (http://gnunify.in).

Yogesh enjoys cutting edge technologies. He is a hardware hobbyist who likes playing with smartphones, tablets, routers, and Arduino. He is big fan of Android and various Linux distributions. He has compiled and modified kernel and firmwares for many phones and routers. He wishes to be a humble contributor to the open source world.

Acknowledgment

I would like to thank my wife fo...

Table of contents

• Programming the BeagleBone