Practical Raspberry Pi (Technology in Action)

Practical Raspberry Pi takes you quickly through the hardware and software basics of the Raspberry Pi. Author Brendan Horan then gets you started on a series of fun and practical projects, including a simple temperature sensor, a media center, a real-time clock, and even a security monitoring device, all of which require minimal programming experience. Along with these projects, you'll learn all about the Raspberry Pi hardware, including how it can be so powerful and still so small and inexpensive, why it's so suitable as a video player, and how you can customize it for different tasks, including running different operating systems on it, including Android and RISC OS. The Raspberry Pi is an inexpensive but relatively powerful little computer. It was designed to get kids interested in computing and programming, but it's also a great platform for hardware hackery. The projects in this book will get you deep into the hardware to show you what the Raspberry Pi can really do. What you’ll learn An overview of Raspberry Pi hardware How to get your Pi up and running with Linux How to use your Pi for sensing temperature and driving a simple character LCD How to create a media player with your Raspberry Pi How to use your Pi as a serial console server How to set up your Pi to be a security monitoring device Other operating systems for your Pi, including Gentoo, Android, and RISC OS Who this book is for Electronics enthusiasts who want to try out the Raspberry Pi, Linux fans who want to create useful projects with the Pi, or anyone interested in learning more about computing, electronics, and networking with this inexpensive and fun little computer. Table of ContentsIntroduction Power and power sources Electronics overview Tools you'll need Chapter 1: Raspberry Pi Hardware Inputs and Outputs Overview of the ARM11 CPU Overview of the Broadcom VideoCore IV GPU Headers and pin out schematics Notes on unusable headers Chapter 2: Software Overview and Installing Linux Why hard-float vs. soft-float is important Installing Fedora Optimizing Fedora to run from the SD Chapter 3: Using GPIO: A Simple Temperature Sensor Overview and warnings about Pi's GPIO Connecting the sensor Writing the code to read the temperature Chapter 4: Driving a Simple Character LCD Using an LCD controller and GPIO Writing to and controlling the LCD Chapter 5: Security Monitoring Device Chapter 6: Cross-compiling Applications for the Pi Why cross-compiling is a good idea Setting up a cross-compile environment on your desktop GCC tips and tricks Chapter 7: Media Center with Raspberry Pi Installing XBMC Setting up HDMI audio and video Chapter 8: Building a Real-time Clock Add an independent RTC to your Raspberry Pi Chapter 9: Embedded, IP-enabled Serial Console Server Accessing the Pi's UART and building a line-level converter Linux serial port server set-up Chapter 10: Appliance Automation Mains voltage warnings Building the hardware Writing the code to turn the appliance on and off Chapter 11: Other Operating Systems for the Pi Android RISC OS Plan9 Gentoo Cover; Title Page; Copyright Page; Dedication Page; Contents at a Glance; Table of Contents; About the Author; About the Technical Reviewers; Acknowledgments; Introduction; Basic Tools; Measure Twice, Cut Once; Basic Schematics and Electronics; Schematics; Electronics Concepts; Ohm's Law; Resistors; Capacitors; Diodes; Series and Parallel Circuits; Pi Power and Clean Input; The Dangers of ESD; SI Units and Measurements; What to Expect; CHAPTER 1 Hardware Overview; Pi In, Pi Out; USB Port; LAN Port; CSI Header; HDMI Port; Power to the Pi!; DSI Header; SD Card Slot; What Is SD?; What Is MMC? The Security Application CodeRunning the Security Application; Summary; CHAPTER 6 Cross Compile Environment; Introducing Cross Compiling; The Host; Crosstool-NG; Configuring crosstool-NG; Paths and Misc Options; Target Options; Tool-Chain Options; Operating System; Binary Utilities; C Compiler; C Library; Debug Facilities; Building the Tool Chain; Preconfigured Tool Chains; Your First Cross Compile; Cross Compiling with Dependencies; Optimization; Summary; CHAPTER 7 Mini Media Center; Why OpenELEC?; Using the -Ofast Optimization; Using the LTO; Using Symbols as Needed; Two Final Advantages Understanding the CFQ SchedulerUnderstanding the Noop Scheduler; Changing the Scheduler; Lighter Applications and Tools; Summary; CHAPTER 3 A Simple Temperature Sensor; Breadboards and GPIO Pins; Sensors; Introducing the DHT11; Introducing the DS18B20; The Amazing 1-Wire Bus; Building the Sensors; Building the Sensors; Using the Little Black DS1820B; Reading the DS1820B on Linux; Using the Big Blue DHT11; Reading the DHT11 in Linux; Scripting the Sensors; Summary; CHAPTER 4 Driving a Simple Character LCD; Pulling Apart the HD44780 and the Clones; Preparing the Hardware; LCD Prep Work Shift RegistersThe I2C Bus; Physical Layout; Raspberry Pi Tolerance and High-Level Voltage Input; Pull-Up Resisters and Open Drains; Addressing I2C Devices; The Bus Itself; Putting It All Together; Finding Your I2C Device; Software and LCD Clients; Server Configuration; Testing the Server; Running a Client; Displaying Text; Summary; CHAPTER 5 Security Monitoring Device; Introduction to the PIR; Introducing the Pressure Mat; Assembling the Devices; The Pressure Mat; Using the GPIO Pins; A Script for Your Mat Status; Connecting the PIR; Bring Forth the WEBrick; Welcome WEBrick What Is SDIO?GPIO Headers; Analog Video Output; JTAG Ports; Audio Output; LEDs; Pi Brains; Processor Pipeline; Caches; Memory Chips; Power States; Performance per Watt; Pi Eyes; What Happens at Power On?; Pi on Your Face; Summary; CHAPTER 2 Installing Fedora; Dissecting the Image; Using the GUI Installer; Using the Command Line; Installing the Image on Windows; Booting Your Pi; Oh No, Goes Crash!; Configure and Look Around; Updating the Firmware and Operating System; Cutting Out the Fat; Optimizing the SD Card; Thinking About Swapping; Optimizing CPU Cycles; I/O Tuning