Adventures in Raspberry Pi

About the Author v


Acknowledgments vi


Introduction 1


Adventure 1 You Have a Raspberry Pi Now What? 9


What Hardware Do You Need? 10


What Other Equipment Is Helpful? 12


Setting Up the Raspberry Pi 14


Downloading and Copying the Raspbian Operating System 14


Preparing an SD Card to Store Your Software 15


Making It Easy with NOOBS 17


Plugging in the Hardware 18


Installing and Configuring the Software 19


Logging in to Your Raspberry Pi 22


Exploring the Desktop in Raspbian 23


Shutting Down Your Raspberry Pi 25


Backing up an SD Card Image 25


Adventure 2 Taking Command of Your Raspberry Pi 27


Exploring the Terminal 29


Commands for Navigating Through Your File System 31


Understanding sudo 35


Launching Programs from the Command Line 35


Managing Files and Directories 36


Installing and Updating Applications 37


Downloading and Installing Applications 37


Learning More About an Application 38


Upgrading Your Apps 39


Editing Files 39


Using Shutdown and Restart Commands 41


Continuing Your Text Adventure 41


Adventure 3 Creating Stories and Games with Scratch 45


Getting Started with Scratch 46


The Scratch Interface 47


A Quick Hello from Scratch Cat 48


Setting the Stage 50


Creating Costumes and Original Sprites 52


Using the Scratch Sprite Image Library 52


Editing an Existing Sprite 52


Creating Your Own Original Sprites 53


Animating a Crazy Monkey 53


Creating an Adventure Role-Playing Game 59


Creating Your Sprite and Stage 59


Setting the Start Position of the Adventurer Sprite 60


Creating Variables: Including Health Points for the Adventurer Sprite 61


Controlling the Direction and Movement of the Adventurer Sprite 63


Entering a Cave and Switching Backgrounds 64


Adding a Script to Make the Adventurer Sprite Move


Between Backgrounds 64


Adding a Script to Switch the Stage 66


Creating an Enchanted Key to Exit the Cave and Giving Extra


Health Points 67


Using "if" Statements to Show and Hide Sprites 69


Creating Health-Point-Stealing Sprites 70


Improving the Movement of the Adventurer Sprite Using "if" Blocks 71


Creating a Game Over Screen 72


Ideas for Improvements to Your Game 73


Adventure 4 Programming Shapes with Turtle Graphics 77


Scratch Turtle Graphics 78


Using Pen Down and Pen Up 79


Drawing Simple Shapes 80


Using "clear" and Setting a Start Point 82


Using Variables Instead of Values 82


Changing the Size and Colour of the Pen 83


Creating Spiral Patterns 84


Using User Input to Determine the Number of Sides 86


Python Turtle Graphics 86


Introducing Python Modules 87


The IDLE Environment and the Interpreter Window 87


Using the Turtle Module in Python 88


Using a Text Editor 90


Using "for" Loops and Lists 91


The "range" Function 93


Other Python Turtle Module Commands 94


Pen Up and Pen Down 94


Setting the Pen Colour and Size 95


Stamping 95


Some Super Spirals 95


Further Adventures with Python Turtle 97


Adventure 5 Programming with Python 101


Getting Set Up for Python 102


Python Programming Language 102


The IDLE Environment 102


Programming in Python: Using a Function 103


Using a Text Editor to Create a Code File 106


Using the Python time and random Modules 108


Python Text Adventure Game 112


Getting User Input 112


Using Conditionals 113


Using a while Loop 116


Using a Variable for Health Points 118


Putting It All Together 119


Defining Functions 121


The get-input Function 121


The handle-room Function 122


Creating a Main Game Loop 122


Continuing Your Python Adventure 126


Adventure 6 Programming Minecraft Worlds on the Raspberry Pi 129


Getting Started with Minecraft Pi 130


Minecraft Pi Controls 132


Your First Minecraft Pi Python Program 133


Using Coordinates in Minecraft Pi 135


Finding the Player s Location 135


Changing the Player s Location 137


Placing a Block 138


Placing Multiple Blocks 139


Creating a Diamond Transporter 142


Sharing and Cloning Minecraft Pi Programs 145


Further Adventures with Minecraft Pi 146


Adventure 7 Coding Music with Sonic Pi 149


Getting Started with Sonic Pi 150


The Sonic Pi Interface 151


Creating Your First Sounds with Sonic Pi 153


Twinkle Twinkle Little Star 155


Repeating Lines in a Loop 158


First Electronic Track 160


Using Different Synthesizer Sounds 160


Using Prerecorded Samples 161


Creating a Surprising Tune 163


Using "rand" to Play Random Notes 163


Using Algorithms 164


Running Two Scripts at the Same Time 166


Adding Effects 167


Make a Recording of Your Music 167


Further Adventures with Sonic Pi 168


Adventure 8 Using the GPIO Pins on the Raspberry Pi 171


Using a Raspberry Leaf Diagram 172


Electronic Basics 175


Using the Python Library to Control GPIO 177


Do You Have a Rev 1 or a Rev 2 Board? 177


Making an LED Blink 179


Creating the LEDblink Python Code 180


Connecting the LEDblink Components 181


Running LEDblink.py as the Super User root 182


Using a Button to Turn on an LED 184


Creating the buttonLED Python Code 184


Connecting the buttonLED Components 185


Running buttonLED.py as the Super User root 186


The Marshmallow Challenge 187


Creating the Marshmallow Button 188


Mapping Marshmallow Input to a Keyboard Key 190


Scratch Marshmallow Game 192


Further Adventures with GPIO Pins 195


Adventure 9 The Big Adventure: Building a Raspberry Pi Jukebox 197


An Overview of the Jukebox Project 198


What You Will Need 199


Part One: Creating the LCD Screen 200


Preparing the LCD Screen by Adding Headers 200


Mounting the LCD Screen and Wiring Up the Breadboard 201


Adding Scripts to Drive the LCD Screen 203


Part Two: Downloading and Playing MP3s 205


Installing a Media Player and Getting Music Files 205


Writing a Jukebox Python Program 208


Part Three: Controlling the Jukebox with Buttons 212


Connecting the Buttons 212


Adapting Your Jukebox Program to Include GPIO Buttons 214


Part Four: Displaying Jukebox Information on the LCD screen 216


Finishing Up 221


Appendix Where to Go from Here 223


Websites 223


Clubs 225


Inspiring Projects and Tutorials 226


Videos 226


Books and Magazines 227


Glossary 229


Index 235