Ripped by AaLl86 Designing Embedded Hardware By John Catsoulis. Publisher: O'Reilly Pub Date: May 2005 ISBN: 0-596-00755-8 Pages: 400 Table of Contents | Index | Errata Embedded computer systems literally surround us: they're in our cell phones, PDAs, cars, TVs, refrigerators, heating systems, and more. In fact, embedded systems are one of the most rapidly growing segments of the computer industry today. Along with the growing list of devices for which embedded computer systems are appropriate, interest is growing among programmers, hobbyists, and engineers of all types in how to design and build devices of their own.
Furthermore, the knowledge offered by this book into the fundamentals of these computer systems can benefit anyone who has to evaluate and apply the systems. The second edition of Designing Embedded Hardware has been updated to include information on the latest generation of processors and microcontrollers, including the new MAXQ processor. If you're new to this and don't know what a MAXQ is, don't worry--the book spells out the basics of embedded design for beginners while providing material useful for advanced systems designers. Designing Embedded Hardware steers a course between those books dedicated to writing code for particular microprocessors, and those that stress the philosophy of embedded system design without providing any practical information.
Having designed 40 embedded computer systems of his own, author John Catsoulis brings a wealth of real-world experience to show readers how to design and create entirely new embedded devices and computerized gadgets, as well as how to customize and extend off-the-shelf systems. Loaded with real examples, this book also provides a roadmap to the pitfalls and traps to avoid. Designing Embedded Hardware includes: The theory and practice of embedded systems Understanding schematics and data sheets Powering an embedded system Producing and debugging an embedded system Processors such as the PIC, Atmel AVR, and Motorola 68000-series Digital Signal Processing (DSP) architectures Protocols (SPI and I2C) used to add peripherals RS-232C, RS-422, infrared communication, and USB CAN and Ethernet networking Pulse Width Monitoring and motor control If you want to build your own embedded system, or tweak an existing one, this invaluable book gives you the understanding and practical skills you need. Designing Embedded Hardware, Second Edition by John Catsoulis Copyright © 2005 O'Reilly Media, Inc.
All rights reserved. Printed in the United States of America. Published by O'Reilly Media, Inc., 1005 Gravenstein Highway North, Sebastopol, CA 95472. O'Reilly books may be purchased for educational, business, or sales promotional use.
Online editions are also available for most titles (safari. For more information, contact our corporate/institutional sales department: (800) 998-9938 or corporate@oreilly. Editor: Andy Oram Production Editor: Sanders Kleinfeld Cover Designer: Emma Colby Interior Designer: David Futato Printing History: November 2002: First Edition. May 2005: Second Edition.
Nutshell Handbook, the Nutshell Handbook logo, and the O'Reilly logo are registered trademarks of O'Reilly Media, Inc. Designing Embedded Hardware, the image of a porcelain crab, and related trade dress are trademarks of O'Reilly Media, Inc. Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in this book, and O'Reilly Media, Inc.
was aware of a trademark claim, the designations have been printed in caps or initial caps. While every precaution has been taken in the preparation of this book, the publisher and author assume no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein. ISBN: 0-596-00755-8 Dedication This book is dedicated to my uncle, Vince Catsoulis Preface [Enlightenment] resides as comfortably in the circuits of a digital computer. as at the top of a mountain or in the petals of a flower.
Pirsig, Zen and the Art of Motorcycle Maintenance Welcome to the second edition of Designing Embedded Hardware. In these pages, I hope to give you an understanding of the design process for creating computer hardware. Just as there is beauty in well-written software, there is beauty in well-designed hardware. With embedded computers, you get to understand the machine at all levels, at once aware of currents flowing through circuit traces and software executing complex algorithms.
In fact, it is not possible to write embedded software without understanding the hardware, nor is it possible to design hardware without understanding software. You become involved with the machine to a degree beyond that which is possible with desktop computers. Best of all, it's a lot of fun. In selecting chips and designs for this book, I have tried to choose, where possible, parts that are both trivial to use yet exceptionally useful.
I have no connection, financial or otherwise, with any of the companies or businesses mentioned in this book, and I receive no benefits from them. Every component or product included in this book is there based on its own merits. You may notice a prevalence of components from certain manufacturers. This simply reflects my personal preference for using their chips, based on my experience.
Such companies produce chips that are easy to use, are reliable and robust, have great technical support, and provide thorough and comprehensive technical data. In other words, they meet all the necessary requirements for inclusion in a book for beginners. When the first edition of Designing Embedded Hardware was published, I deliberately left out software. There were two reasons for this.
First, there are many good books already written on C programming, embedded firmware development in C, porting Linux to embedded systems, coding in Python, writing Java software, and so on. (And of course, the best of these are naturally published by O'Reilly.) The second reason is that assembly language, that most basic of programming tools, is so different from processor to processor that it would not have been possible to cover all the instruction sets of the processors in the book, let alone do them justice. However, I have decided to include some software in this edition. I won't even attempt to cover the instructions of each processor in this book.
What I will do is show some simple assembly language techniques. While the instructions may be wildly different between architectures, the basic concepts are the same. Also new to this book is a chapter on the Forth programming language. Forth is a relatively old language that has faded from the forefront of software development, and as such, it's rare to find a book giving the language good coverage.
Forth is a very useful tool for embedded system development to which many engineers have yet to be exposed. The language is the basis of the Open Firmware standard and is used by design engineers at Apple, Sun, and many other manufacturers. It's a useful language to know, and it is worth taking the time to learn. Many of the designs in this book look easy, and they are.
They are intended as simple building blocks, allowing you to mix and match to achieve the embedded systems you need. I hope you will find this book useful. Once you've finished reading it, go and build something! —John Catsoulis Brisbane, Australia January 2005 jtc@embedded.au http://www.au Organization of This Book This book is informally divided into four sections. The first covers fundamental concepts and introductory material.
The second section gives an overview of assembly language and Forth. From there, we'll look at peripherals and how to add functionality to your embedded systems. Finally, we'll look at a variety of processors widely used in embedded systems, and look at the design process for integrating them into computers. Chapter 1 gives an overview of computer architectures and explains what constitutes an embedded system.
Chapters 2 and 3 explore software with assembly language and Forth. Chapter 4 provides some background electronics theory and introduces some important concepts. If you're already electronics-savvy, then you can skip on to Chapter 5, where we'll look at providing power for your embedded system. We'll also look at how to protect your embedded computer against electrical interference and other gremlins that can cause it grief.
In Chapter 6, you'll see how to physically produce and debug an embedded computer system. Chapters 7 and 8 cover SPI and I2C, two protocols that allow a wide range of small peripherals to be added to microcontrollers. Chapters 9, 10, and 11 cover serial interfaces. These give our embedded system access to host computers and to external peripherals such as modems.
We'll look at RS-232C, RS-422, Infrared communication, and USB. Networks are covered in Chapter 12, where we'll see how to add a low-cost industrial network (CAN) to our embedded computer. Also in Chapter 12, we learn how to add an Ethernet port to our embedded system, by which we can connect to other computers, servers, and gateways and, through them, to the wider Internet. In Chapter 13, we'll look at real-world interfacing.
We'll see how to convert analog signals into digital values for processing and, conversely, how to convert digital values back into analog voltages. We'll also see how to interface sensors to our embedded system, whereby we can measure temperature, light, pressure, acceleration and magnetic fields. Also in Chapter 13, we'll look at Pulse Width Modulation and motor control. We'll see how to use an embedded computer to control small electric motors.
Chapter 14 begins the microprocessor section of the book, where we'll look at the first of our embedded processor architectures, the Microchip PIC. In subsequent chapters, we'll meet a variety of processors, from tiny standalone, 8-bit microcontrollers to 32-bit, bus-based chips with some computing grunt. While it is not possible to cover every embedded processor (as there are literally many hundreds), the chips chosen are representative of various classes of processor. The skills you learn will be adaptable to whatever processor you choose for your application.
Using Code Examples This book is here to help you get your job done. In general, you may use the code in this book in your programs and documentation. You do not need to contact O'Reilly for permission unless you're reproducing a significant portion of the code. For example, writing a program that uses several chunks of code from this book does not require permission.
Selling or distributing a CD-ROM of examples from O'Reilly books does require permission. Answering a question by citing this book and quoting example code does not require permission. Incorporating a significant amount of example code from this book into your product's documentation does require permission. We appreciate, but do not require, attribution.
An attribution usually includes the title, author, publisher, and ISBN. For example: "Designing Embedded Hardware, by John Catsoulis. Copyright 2005 O'Reilly Media, Inc." If you feel your use of code examples falls outside fair use or the permission given above, feel free to contact the publisher at permissions@oreilly. Conventions The conventions used in this book are as follows: Main text Source Code Signal (active high) (active low) Hexadecimal numbers are denoted with the prefix 0x, and sometimes with the prefix $, where appropriate for certain processors.
Binary numbers are denoted by the prefix %. K is 1,024, while k is 1,000. This icon indicates a tip, suggestion, or general note. This icon designates a caution or warning.
Safari® Enabled When you see a Safari® Enabled icon on the cover of your favorite technology book, it means the book is available online through the O'Reilly Network Safari Bookshelf. Safari offers a solution that's better than e-books. It's a virtual library that lets you easily search thousands of top technology books, cut and paste code samples, download chapters, and find quick answers when you need the most accurate, current information. Try it for free at http://safari.
How to Contact Us Please address comments and questions concerning this book to the publisher: O'Reilly Media, Inc. 1005 Gravenstein Highway North Sebastopol, CA 95472 (800) 998-9938 (in the United States or Canada) (707) 829-0515 (international/local) (707) 829-0104 (fax) There is a web page for this book, which lists errata, examples, and any additional information. You can access this page at: http://www.