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TeAM YYePG Digitally signed by TeAM YYePG DN: cn=TeAM YYePG, c=US, o=TeAM YYePG, ou=TeAM YYePG, email=yyepg@msn. com Reason: I attest to the accuracy and integrity of this document Date: 2005.04.11 14:40:33 +08'00' Open-Source Robotics and Process Control Cookbook This page intentionally left blank Open-Source Robotics and Process Control Cookbook Designing and Building Robust, Dependable Real-Time Systems by Lewin A.R.W. Edwards AMSTERDAM • BOSTON • HEIDELBERG • LONDON NEW YORK • OXFORD • PARIS • SAN DIEGO SAN FRANCISCO • SINGAPORE • SYDNEY • TOKYO Newnes is an imprint of Elsevier Newnes is an imprint of Elsevier 30 Corporate Drive, Suite 400, Burlington, MA 01803, USA Linacre House, Jordan Hill, Oxford OX2 8DP, UK Copyright © 2005, Elsevier Inc. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Permissions may be sought directly from Elsevier’s Science & Technology Rights Department in Oxford, UK: phone: (+44) 1865 843830, fax: (+44) 1865 853333, e-mail: permissions@elsevier.com.uk. You may also complete your request on-line via the Elsevier homepage (http://elsevier.com), by selecting “Customer Support” and then “Obtaining Permissions.” Recognizing the importance of preserving what has been written, Elsevier prints its books on acid-free paper whenever possible. Library of Congress Cataloging-in-Publication Data (Application submitted.) British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library. ISBN: 0-7506-7778-3 For information on all Newnes publications, visit our Web site at www.books.elsevier.com 04 05 06 07 08 09 10 9 8 7 6 5 4 3 2 1 Printed in the United States of America. Dedication This book is dedicated to my wife Cristen, in recognition of her uncomplaining acceptance of yards of PVC conduit in hallways, pounds of gel-cells in the living room, and never-ending snarls of wire and motors throughout the house. v This page intentionally left blank Contents About the Author ........................................................................... xi What’s on the CD-ROM?...............................................................xii Chapter 1: Introduction ................................................................... 1 1.1 History of this Book and What You’ll Get From Reading It .........................1 1.2 Target Readership and Required Skills and Tools .........................................5 1.3 Conventions Used in the Text.......................................................................7 Chapter 2: Microcontrollers, Single-Board Computers and Development Tools .................................................................. 9 2.1 The Division of Labor ....................................................................................9 2.2 Candidate Microcontrollers for ‘Hard’ Tasks ...............................................13 2.3 The Atmel AVR and its Development Hardware Up Close .......................17 2.4 Candidate x86-based SBCs for ‘Soft’ Tasks .................................................21 2.5 The Advantech PCM-5820 Single-Board Computer Up Close .................27 2.6 Selecting an Inter-Module Communications Protocol ...............................32 Chapter 3: Some Example Sensor, Actuator and Control Applications and Circuits (Hard Tasks) ...................... 41 3.1 Introduction .................................................................................................41 3.2 E2BUS PC-Host Interface ...........................................................................44 3.3 Host-to-Module Communications Protocol ................................................49 vii Contents 3.4 Stepper Motor Controller ............................................................................52 3.5 Speed-Controlled DC Motor with Tach Feedback and Thermal Cutoff.......70 3.6 Two-Axis Attitude Sensor using MEMS Accelerometer ............................79 3.7 RS-422—Compatible Indicator Panel.........................................................90 Chapter 4: The Linux-Based Controller (A Soft Task)................... 115 4.1 A Brief Introduction to Embedding Linux on PC Hardware ....................115 4.2 Configuring the Development System and Creating Our Custom Kernel ..117 4.3 The Linux Boot Process—Creating a Bootable CompactFlash Card .......123 4.4 Creating a Root Filesystem for our Embedded System ..............................128 4.5 Creating a Bootable Linux System-Restore CD-ROM Disc .....................136 4.6 Using the Parallel Port as a General-Purpose I/O Interface in Linux .......142 4.7 Implementing Graphical Control Interfaces .............................................149 4.8 Infra-Red Remote Control in Linux Using LIRC .....................................175 4.9 Introduction to Machine Vision Using Video4Linux ...............................189 4.10 Customizing Your BIOS—The Structure of a Modern BIOS .................201 Chapter 5: Encryption and Data Security Primer .......................... 209 5.1 Introduction ...............................................................................................209 5.2 Classes of Algorithm ..................................................................................214 5.3 Protecting One-Way Control Data Streams ..............................................217 5.4 Protecting One-Way Telemetry .................................................................218 5.5 Protecting Bidirectional Control/Data Streams ........................................220 5.6 Protecting Logged Data ..............................................................................222 5.7 Where to Obtain Encryption Algorithms .................................................224 viii Contents Chapter 6: Expecting the Unexpected........................................... 227 6.1 Introduction ...............................................................................................227 6.2 Dangerous Exception Conditions and Recovering From Them ...............228 6.3 On-Chip vs. Off-Chip Watchdog Hardware .............................................230 6.4 Good Power-On Reset Practices ................................................................232 6.5 A Few Additional Considerations for Battery-Powered Applications ......235 Chapter 7: Contents of the Enclosed CD-ROM ............................ 237 Index ........................................................................................... 237 ix