Table Of Content

Designing Embedded Internet Devices [This is a blank page.] [This page intentionally left blank.] Designing Embedded Internet Devices by Dan Eisenreich Brian DeMuth An imprint of Elsevier Science Amsterdam Boston London New York Oxford Paris San Diego San Francisco Singapore Sydney Tokyo Newnes is an imprint of Elsevier Science. Copyright © 2003, Elsevier Science (USA). 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. Recognizing the importance of preserving what has been written, Elsevier Science prints its books on acid-free paper whenever possible. Library of Congress Cataloging-in-Publication Data ISBN: 1-878707-98-1 British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library. The publisher offers special discounts on bulk orders of this book. For information, please contact: Manager of Special Sales Elsevier Science 200 Wheeler Road Burlington, MA 01803 Tel: 781-313-4700 Fax: 781-313-4882 For information on all Newnes publications available, contact our World Wide Web home page at: http://www.newnespress.com 10 9 8 7 6 5 4 3 2 1 Printed in the United States of America iv Acknowledgments We would like to gratefully acknowledge … the fine folks at Dallas Semiconductor for squeezing such a capable JVM on an 8-bit microcontroller. … all of the hard work proofreading and organizing the draft for the book by the folks at Newnes (Kelly, Carol, Harry). Dedication Dan To Keisha and Emily Brian To Linda, whose love and support made this possible. ....................................A...c..k..n..o..w...l.e..d..g.ments ...............................................................D...e..d..ication W.h..a..t.(cid:144)s.. .o...n.. .t.h..e.. .C...D..-..R..O...M...?.......... 1 Introduction................................................................ 1 Why should you read this book?............................................... 1 What this book will do for you ................................................... 2 How this book is laid out ........................................................... 2 How to get the most out of this book......................................... 3 What you should already know ................................................. 4 2 Computer Networks................................................... 5 A really simple network............................................................. 6 A small office and home network .............................................. 7 Connecting a LAN to the Internet (or a LAN, MAN, WAN)........ 8 Broadband connection............................................................................. 8 Alternate broadband connection.............................................................. 9 Dial up connection................................................................................... 9 The 10/100 Base- T cable......................................................... 11 Ethernet address....................................................................... 13 Internet addresses .................................................................... 14 Domain names.......................................................................... 14 Network classes........................................................................ 14 Subnetworks ............................................................................. 16 DHCP........................................................................................ 17 Protocols ................................................................................... 18 Client/server.............................................................................. 20 3 Java Essentials for Embedded Networked Devices .......................................................................... 25 For Windows............................................................................. 26 Windows 95/98........................................................................................ 26 Windows 2000, Windows NT, Windows XP............................................. 26 For Linux ................................................................................... 28 For Windows............................................................................. 31 Windows 95/98........................................................................................ 32 Windows 2000, Windows NT, Windows XP............................................. 32 For Linux ................................................................................... 34 Classes, objects, methods, constructors................................... 37 OOP diagrams .......................................................................... 39 Inheritance ................................................................................ 41 Errors, exceptions, and exception handling .............................. 51 Network Programming .............................................................. 59 Reading and writing to a socket (a simple client)..................................... 60 Reading and writing to a socket (a simple server)................................... 63 Reading and writing to a socket (a slightly less simple server)................ 67 Programming with URLs.......................................................................... 73 Threads..................................................................................... 74 Implementing threads by extending the thread class............................... 75 Implementing threads by implementing the runnable interface............... 82 Serial ports................................................................................ 85 4 Overview of Embedded Networked Devices ........... 93 5 Getting Started with TINI........................................... 101 The TINI SIMM.......................................................................... 102 The socket board ...................................................................... 103 Get your TINI running................................................................ 105 For Windows............................................................................. 107 Windows 95/98.......................................................................... 107 Windows 2000, Windows NT, Windows XP.............................. 108 Linux.......................................................................................... 108 Running JavaKit........................................................................ 109 Your first TINI program.............................................................. 114 Windows.................................................................................... 117 Windows 95/98........................................................................................ 118 Windows 2000, Windows NT, Windows XP............................................. 118 Linux.......................................................................................... 119 Hardware................................................................................... 119 First 1-Wire program ................................................................. 120 Compile from Windows, run from Windows .............................. 122 Compile from Windows, run from TINI...................................... 122 Compile from Linux, run from Linux.......................................... 124 Compile from Linux, run from TINI............................................ 124 6 The TINI Hardware ..................................................... 127 Versions .................................................................................... 128 A high-level look at TINI............................................................ 129 What(cid:144)s in a TINI stick? ............................................................................. 129 A quick look at how it works..................................................................... 130 The SIMM (Single Inline Memory Module) edge connector...... 130 The processor and oscillator module........................................ 133 Programming example: the watchdog timer............................................ 137 A few words about the TINI address space............................................. 139 The TINI memory map............................................................................. 140 Flash ROM............................................................................................... 141 Static RAM............................................................................................... 143 The RAM nonvolatizer............................................................... 144 The CPU Reset circuitry............................................................ 146 The internal 1-Wire net.............................................................. 147 The external 1-Wire I/O, or iButton interface............................. 149 The RS232 interface ................................................................. 150 The real-time clock.................................................................... 151 Programming example: using the real-time clock..................... 153 The Ethernet controller.............................................................. 155 The I2C interface....................................................................... 157 The CAN interface..................................................................... 158 What(cid:144)s in an E20 socket board? ............................................... 158 The E20 in greater detail........................................................... 160 The serial interface and DTR reset enable.............................................. 160 The external 1-Wire interface................................................................... 162 The Ethernet interface............................................................................. 162 The CAN interface................................................................................... 163 The regulated power supply..................................................................... 164 Additional FLASH..................................................................................... 164 Support for Serial2 and Serial3................................................................ 167 External interrupt selection circuitry......................................................... 168 Internal 1-Wire interface........................................................................... 169 The parallel IO section............................................................................. 169 The LCD interface from earlier versions.................................................. 172 Vinculum Technologies Group.................................................. 173 Systronix ................................................................................... 174 Additional products and vendors............................................... 174 Making a custom TINI socket.................................................... 175 7 The TINI Software....................................................... 177 Terminal .................................................................................... 180 Starting slush ............................................................................ 191 Slush commands....................................................................... 193 Managing programs and files................................................................... 194 Managing users....................................................................................... 196 Managing connectivity............................................................................. 196 Miscellaneous slush commands.............................................................. 198 Optional slush commands........................................................................ 198 Slush files and environment...................................................... 199 passwd..................................................................................................... 199 startup file................................................................................................ 200 tininet file.................................................................................................. 201 User Home............................................................................................... 201 login file.................................................................................................... 202 Servers in slush....................................................................................... 202 Tips for your programs.............................................................. 205 Threads.................................................................................................... 205 Memory.................................................................................................... 205 Networking............................................................................................... 206 Good ideas............................................................................................... 206 Java classes/methods (API 1.02d).......................................................... 206 File system............................................................................................... 207 TINIConvertor............................................................................ 208 BuildDependency...................................................................... 209 A TINI example ......................................................................... 211 Modifying slush ......................................................................... 219 Recompiling Slush................................................................................... 219 Modifying the slush command set............................................................ 224 Adding optional commands to slush........................................................ 226 Adding new commands to slush.............................................................. 227 Utilities....................................................................................... 232 Using DOS batch files.............................................................................. 232 Using FTP................................................................................................ 235 Using the DOS command window........................................................... 236 GNUmake ................................................................................. 237 Linux.......................................................................................... 237 Windows.................................................................................... 237 JEdit.......................................................................................... 240 TiniHttpServer........................................................................... 242 TiniInstaller................................................................................ 242 TINIAnt...................................................................................... 242 8 Enhancing TINI........................................................... 245 Adding data bus buffer.............................................................. 256 The address decoder ................................................................ 256 Adding an LCD display.............................................................. 260 Adding buttons.......................................................................... 273 Adding a keypad ....................................................................... 280 Add an LED display................................................................... 286 9 TINI Serial and Parallel I/O ........................................ 295 A few serial port details............................................................. 296 The UART................................................................................................ 296 Flow control, parity, stop bits, data format............................................... 296 Serial line voltages................................................................................... 298 Cables and connectors............................................................................ 300 TINI serial ports......................................................................... 305 Serial0...................................................................................................... 307 Serial1...................................................................................................... 309 Serial2, 3.................................................................................................. 310 Serial communication software (API)........................................ 311 A serial example........................................................................ 313 Serial0...................................................................................................... 313 Serial1...................................................................................................... 321 Serial2 and serial3................................................................................... 328 A parting word on serial ports ................................................... 330 TINI parallel ports...................................................................... 332 Port control............................................................................................... 332 Parallel I/O buffers/drivers....................................................................... 332 Parallel communication software (API)..................................... 334 A simple parallel device example.............................................. 337 Another example....................................................................... 341 Other ways of handling parallel I/O........................................... 344 10 Wire Basics for TINI................................................. 345 Wire Reset Details .................................................................... 350 Wire Data Communication Details............................................ 350 The Read ROM command........................................................ 354 The Search ROM command ..................................................... 356 Match ROM............................................................................... 358 Skip ROM.................................................................................. 358 Memory commands................................................................... 359 DS2405 Addressable Switch ROM commands......................... 363 The DS2405 Match ROM command......................................... 364 The DS2405 Search ROM command ....................................... 364 The Active Only Search ROM command................................................. 364 DS1920 ROM commands......................................................... 367 The DS1920 Alarm Search command ...................................... 367 Communication ports on the PC ............................................... 371 The RS232 or serial (COM) ports............................................................ 372 The parallel or printer port........................................................................ 375 PC universal serial bus, or USB............................................................... 377 Cables and connectors............................................................................ 378 The 1-Wire Java API, TMEX drivers, and these mysterious things called port adapters........................................................ 380 Example: finding all 1-Wire devices on a specific port.............. 382 The DSPortAdapter class........................................................................ 383 The OneWireAccessProvider class......................................................... 384 The Enumeration class............................................................................ 385 The OneWireContainer class................................................................... 385 Example: Finding devices by family on a specific port.............. 394 Example: Identifying all software port adapters present ........... 396 Example: Finding the default adapter ....................................... 398 Example: Finding all 1-Wire devices on any port...................... 400 Example: Controlling the DS2405 addressable switch ............. 401 The OneWireContainer05 class............................................................... 402 Example: Measuring temperature with a DS1920 temperature iButton................................................................... 411 The OneWireContainer10 class............................................................... 411 The TINI external 1-Wire bus.................................................... 419 The TINI internal 1-Wire bus..................................................... 420 TINI port adapter objects........................................................... 420 The TINI API ............................................................................. 421 Example: A Java program for TINI that identifies port adapters.............. 421 Example: Determining the default port on TINI........................................ 421 Example: Determining the ROM ID for all 1-Wire devices attached to TINI.......................................................................................................... 422 Example: Another way of determining the ROM ID for all 1- Wire devices attached to TINI................................................... 425 Example: Yet another way of determining the ROM ID for all 1- Wire devices attached to TINI.......................................... 428 Example: Controlling a DS2405 addressable switch from TINI ........................................................................................... 430 Example: Using a temperature iButton with TINI...................... 430 11 The I2C Bus.............................................................. 433 The master/slave concept in I2C............................................... 434 The I2C data format .................................................................. 435