Learn to Program in Arduino™ C

287 Pages·2017·3.61 MB·English

Learn to Program
in Arduino™ C:
18 Lessons, from setup() to robots
William P. Osborne holds a BSEE and an MIT (master's degree in teaching) from
Seattle University and an MBA and an MS from Stanford University. His career has
included consulting to technology manufacturers, running a small software company,
and ten years at the Microsoft Corporation, primarily in the Windows operating sys-
tem division. He teaches computer science and engineering at a public high school.
© Copyright 2017, William P. Osborne
Earlier versions of this book were shared on the author's website, LearnCSE.com.
Printed in the United States of America
Published by Armadillo Books
Printed by CreateSpace
ISBN: 978-0-9981287-1-9
Edited by Margo Paddock
Book design by Margo Paddock
Cover design by Abby Osborne
Photographs by Abby Osborne and Caroline Osborne
Although the electronic design of the Arduino™ boards is open source (Creative Com-
mons CC-SA-BY License) the Arduino™ name, logo, and the graphic design of its
boards are protected trademarks of Arduino LLC (USA).
Introduction
The Arduino™ is an extremely popular single-board computer that can be used to make a vast va-
riety of intelligent devices. With this book you will learn how to work with the Arduino™ itself, to
identify and control common electronic components used with an Arduino,™ and, most important
of all, to write programs for the Arduino.™
This book is for you if you want to understand, program, and use the Arduino™ to make things
that work. It is also for you if you want to teach Arduino™ programming. We believe this mastery
is valuable for three reasons:
1. Industry demands and career opportunity: The key component of the Arduino™ is a mi-
crocontroller from the Atmel Corporation. Learning to program and apply an Arduino™
is also learning to program and apply a microcontroller, a skill that is in heavy demand in
industry.
2. As a basis for learning other programming languages: The Arduino™ is programmed in a
version of the C programming language. Consequently, knowledge of the syntax of Ardu-
ino™ C transfers to learning higher-level languages, including C++, C#, Java, and Python,
which are all currently used in industry.
3. Satisfaction and fun: The Arduino™ can be used as the computing component for many
different kinds of devices. Students who have completed the lessons in this book have gone
on to design, build, and program robots that walk, sensors that record and report data,
musical instruments, and quadcopters that fly, among other things.
You will guide and pace your own learning. Each lesson builds upon and extends the content of
the preceding lessons. And each lesson is constructed as it would be presented in a classroom, be-
ginning first with key concepts and ending with exercises in applying that knowledge:
Big Idea: The major concept or skill the lesson conveys. Everything else in the lesson supports
this idea.
Background: The underlying theory, and, when appropriate, the science behind the content
of the lesson. Understanding the background of new material enhances your ability to apply
that knowledge.
Vocabulary: New terms are highlighted in yellow when they introduced in text. Those terms
and their definitions are also conveniently arranged in a table (with a yellow banner heading)
for reference.
Description: Further detail of the concepts covered in the lesson and other information that
will put the lesson's procedure and exercises into the context of the Big Idea.
Goals: The specific set of concepts you will learn and skills you will develop while completing
the lesson.
Materials: A list of the electronic materials and tools used in the lesson. Each item on the list
has a number linking it to a Parts Catalog (available at LearnCSE.com), which provides infor-
mation about where the part can be purchased.
Procedure: A set of ordered steps for conducting the experiment or building the project that
illustrates the content of the lesson.
Exercise(s): A set of one or more additional experiments or projects you can do in order to
apply and reinforce what you have learned in the lesson.
Support in the form of sample programs (referred to as "sketches") for the Arduino,™ FAQs, the
Parts Catalog, new topics and projects, and a blog can be found at www.LearnCSE.com.
The lessons in this book have been classroom tested. Students have created projects of their own
designs based on what they've learned with earlier versions of these lessons. They have made model
helicopters and airplanes, elaborate rolling robots, musical instruments, light panels, keyboards to
drive synthesizers, "laser" tag games, hover boards, Segway-like vehicles, and more.
Whether you are exploring this book for yourself or to teach others, I hope you find the content
engaging and useful. I invite you to share your thoughts, suggestions, and cool projects of your
own. Visit us anytime at www.LearnCSE.com.
Learn to Program in ArduinoTM C: 18 Lessons, from setup() to robots
Lesson 1: Microcontrollers and SBCs
LELSeSsOsNonS 1 Microcontrollers and SBCs
1
The Big Idea:
This book is about computer science.
It is not about the Arduino,™ the C programming language, electronic components, or the mathe-
matics of electricity—even though we refer to them extensively in the lessons in this book.
The Arduino,™ the C programming language, electronic components, and
the mathematics of electricity are the tools this book uses to teach computer
science.
These tools allow readers to learn by doing, to learn with their hands. Every lesson is either an ex-
periment or a project. Some projects, lighting LEDs, for example, are simple. Others are complex.
Laser tag is an excellent example. But simple or complex, none of the projects does anything unless
some computer science has been applied to bring them to life.
Background: What, precisely, is computer science?
For the purposes of this text, computer science is the application of numbers and logic to make
devices, algorithms, and languages that, together, can model just about anything. This book uses
the tools listed in Table 1-1.
Table 1-1. Tools this book uses
Tool Description
devices The Arduino™ family of Single-Board Computers (SBCs).
algorithms The collection of programming techniques, tools, and libraries we use to
build our models.
language The C programming language.
Lesson 1 Microcontrollers and SBCs
The key word is model. Consider Table 1-2, examples of the uses of models in computing.
Table 1-2. Examples of models in computing
Example What is modeled How model connects to world
League of A fantasy world where Players (humans) participate by controlling
Legends characters possess mag- the actions of some of the characters. High
ical and physical powers. quality graphics and game play allow the
user to suspend disbelief and pretend the
world is real and that the player is actually
the character being controlled.
Digital medical The detailed densities of By collecting data about minute movement
imaging via Mag- the portions of the body of molecules in response to a changing
netic Resonance being scanned. magnetic field, a model of the scanned ob-
ject is created. This model is presented to
the user as startlingly detailed 2D and 3D
images of what would be found if the sub-
ject were opened surgically.
Microsoft Word The appearance of for- The user can add to and modify both the
matted text as if it were content and appearance of this text and can
typed directly onto a cause a copy of the model to be printed on
piece of paper. paper.
Aircraft Autopilot The stable flight of an air- The computer collects data (speed, direc-
craft. tion, physical orientation of the aircraft, al-
titude) and uses the model to control wing
surfaces and engine speed.
Notice that in each case the computer creates and maintains a model. That model might be some-
thing that exists in reality or something entirely fictional. And the output from the model may
be information that appears on a screen, instructions that control physical devices, or a physical
product, such as text or graphics printed on paper or plastic.
The important takeaway is this: all computer programs are models.
The lessons in this book contain experiments and projects that explore concepts and build mod-
els that control lights, make sounds, run robots, turn motors, detect and compose messages, and
more. Some of these models will collect and respond to data from their environments. Some will
provide text as their output, and others will control physical devices. But every experiment and
project is controlled by an Arduino™ running a model of what is being built. And, that model will
be written with the C programming language.
Learn to Program in ArduinoTM C: 18 Lessons, from setup() to robots
Table 1-3. Vocabulary
1
Term Definition
algorithm A means of or steps to performing a specific
task. For a computer, an algorithm is usually ex-
pressed in a set of computer program instruc-
tions.
Arduino™ A single-board computer and an open-source
electronics platform based on easy-to-use
hardware and software. It's intended for anyone
making interactive projects.
C programming language The programming language used to write sketch-
es for the Arduino™ SBC. The syntax is similar
to several other commonly used programming
languages, including C++, C#, and Java.
Integrated Development Environment A collection of computer programs used to cre-
(IDE) ate other computer programs.
microcontroller A complete self-contained computer in a chip,
including the memory for a program and its
data. This small microprocessor also contains
the necessary electronics to communicate with
external devices.
microprocessor A complex electronic integrated circuit that per-
forms the processing tasks of a computer, in-
cluding input, output, and computation.
output Information of any sort that comes out of a com-
puter.
single-board computer (SBC) An entire microcomputer on a single printed cir-
cuit board. Abbreviated SBC. Examples include
the Arduino™ and the Raspberry Pi.
sketch A computer program written for the Arduino™.
Description:
Arduino™ is a name given to a family of single-board computers (SBCs). The particular family
member used in lessons in this book is the Arduino™ Uno. All Arduinos™ contain an integrated
circuit called a microcontroller. A microcontroller is a small but complete microprocessor capable
of input, output, and computation. In addition, a microcontroller includes storage memory for a
computer program and its data.
Lesson 1 Microcontrollers and SBCs
Figure 1-1. The Arduino™ Uno

Surrounding this microcontroller are the electronic components, connectors, and rows of sockets
necessary to bring power to the microcontroller, allow it to receive information from the outside
world, and to transmit information.
The term single-board means that the entire computer fits on a single circuit board. Different mem-
bers of the Arduino™ family have different features. Some are small and light enough to be sewn
into clothing, while others are sufficiently powerful to perform complex tasks very quickly. But
they are a family in that they are all programmed with the same language. The syntax of this lan-
guage is so very close to C that it is referred to as the C language. Mastery of this language serves as
an excellent base for other commonly used programming languages, including C++, C#, and Java.
The upcoming lessons explore most of the features of the Arduino™ Uno. This first lesson begins
with installation and testing of the set of computer programs used to write and install Arduino™
sketches. This collection of computer programs is called the Arduino™ Integrated Development
Environment (IDE). A program written for the Arduino™ is called a sketch.
Learn to Program in ArduinoTM C: 18 Lessons, from setup() to robots
Goals:
1
By the end of this lesson you will:
1. Know the purpose of an Integrated Development Environment (IDE).
2. Know how to locate, download, and install the Arduino™ IDE.
3. Be able to modify, save, upload, and run simple sketches for the Arduino.™
4. Know that sketch refers to a computer program written for the Arduino.™
Materials:
Quan- Catalog
Part Image Notes
tity Number
Single-board computer. This
board is delicate and should
1 Arduino™ Uno be handled with care. When 3102
you are not using it, keep it in
a box or plastic bag.
This is the standard USB
adapter cable with the flat
1 USB Cable connector on one end and 2301
the square connector on the
other.
Computer with at least
one USB port and ac- The operating system of this
1 cess to the Arduino™ --- computer must be Windows, ---
website, Macintosh OS/X, or Linux.
http://www.Arduino.cc
Procedure:

These instructions are for Windows and will work in most situations. For Macintosh
and Linux, refer to the instructions on the Arduino™ website:
Important http://www.Arduino.cc
Lesson 1 Microcontrollers and SBCs
Part I: Download, install, and test the Integrated Development Environment
1. Open Internet Explorer or anoth-
er Internet browser and navigate to
the Arduino™ website http://www.
Arduino.cc.
2. Locate the "Download" section of
the page and select [Windows].
This will begin the download of the
package that will install the IDE.
3. Double-click the Arduino™ icon.
A warning message may appear.
If it does, click the [Run] button.
Learn to Program in ArduinoTM C: 18 Lessons, from setup() to robots