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.

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I’d like to give a special thank you to my editors, Andy Oram and Mike Hendrickson. I’d also like to thank Jon Orwant, editor of the first edition. In the past, I have often read in prefaces how authors thank their editors for the help they gave. It is only now that I understand the depth and significance of this help.

As you have no doubt already noticed, O’Reilly publishes beautifully presented books. I would like to thank the production team, especially Sanders Kleinfeld, for their hard work. This book is as much the result of their efforts as it is mine. I’d also like to thank David Chu for all his help.

Thank you to Dallas Semiconductor, Kathy Vehorn, Don Loomis, Mike Quarles, and Moe Rubenzahl for their assistance and for allowing me access to pre-release versions of the MAXQ processor. Thank you to Peter Paine, Donna Mack and Cooper Tools, Karen Rolan and Fluke Corporation, and Tektronix for allowing me to use their images in the book. Thank you also to Rupert Baines of Picochip for his assistance.

Geoff McDonald has been a great friend and has made many helpful suggestions regarding the content of this book. He also proofread the book, and I thank him for all his help.

Thanks to Michael, Mary, Renee, and Mitchell Lees. Michael did significant proof-reading and offered many helpful comments.

I’d like to thank Dr. Jeff O’Keefe for his long friendship and support over the years. He’s been a good friend ever since we were undergrads together, blowing up integrated circuits and irradiating lecturers in second-year lab!

Thank you to Prof. Neil Bergmann, Dr. John Williams, Keith Ball, Denis Bill, Barry Bettridge, and the staff of the School of ITEE at the University of Queensland for their help and support.

I’d like to thank my friends and colleagues David Nicholls, Peter Stewart, Mark Gentile, Professor John Devlin, Richard Wiltshire, Michelle and Robert Salier, Addy and Derek Clark, Kam Tam, Phil McDonald, and Vamsi Madasu.

Finally and most importantly, I’d like to thank my extended family for their love and support. Most especially, I’d like to thank my sister Kris, and my two nephews, Andrew and James, whose love and good humor have made life worth living. I’d also like to thank Chris and Jeff Goopy for always being there, and my cousins Theo and Maree; David and Jenevieve; Michael, Andrew and Karen; Antony; and Fiona, Drew, Ashley, and Max for their care and support. A special thank you to my uncles, Vince and Dave Catsoulis, who have shown me the meaning of love, honor, and strength of character. I owe them much.