Apple I Replica Creation
Apple I Replica Creation: Back to the Garage
by Tom Owad
Technical Editor: Dr. John Greco
Foreword by: Steve Wozniak
"The author's style is conversational and light. Where another author might have been tempted to descend into pedantic lecturing, Tom has deftly avoided this trap. It is a rare gift to be able to teach complex subjects and keep it light. I, for one, am thankful! ... All in all a great read and highly recommended. If you are a Mac enthusiast, an electronics hobbyist or otherwise technically curious, you will enjoy it." - Will Senn, OSNews Review
From the Foreword by Steve Wozniak:
“The Apple ][ was really the computer designed from the ground up that would kick off personal computing on a large scale. But the Apple I took the biggest step of all. Some very simple concepts are very hard to do the first time. This computer told the world that small computers should never again come with geeky front panels, but rather with human keyboards, ready to type on."
1. BUILD IT
What’s a little dried blood on the breadboard? A small price to pay for having some fun with multimeters, logic probes, wire-wrap tools, soldering irons, TTL chips, circuit boards, chip pullers, and straighteners.
2. PROGRAM IT
Tough guys don’t code with Visual Studios and Object Libraries. They program their hardware the most efficient and difficult way possible: assembly language.
3. PLAY WITH IT
Once you’re done, begin writing software and modifying the hardware design. The results will both impress and scare your friends. Remember, beauty is in the eye of the beholder.
4. MODIFY IT.
McCAD EDS-SE400 is an integrated Electronic Design System which takes the designer through the complete design cycle: Schematic capture, PCB layout, and board fabrication. McCAD software gives the electronic designer the technical range needed, and at the same time provides control and flexibility. The Apple1 Replica was designed with McCAD EDS SE400.
An in-depth description of the book by author Tom Owad:
The aim of Apple I Replica Creation is to guide the reader in building, programming, and understanding the Apple I. The book begins with a history of the Apple I, but not the sort of corporate history you may be used to reading. This account is of the computer itself, the early peripherals and modifications, and the hobbyists and visionaries who bought and used the the Apple I.
The second chapter describes the tools and parts needed to complete the project and chapter 3 introduces reader to digital circuits. This chapter is very hands-on. It introduces basic logic gates and a few designs you can build with them. This chapter won't make you an engineer, but it will give you everything you need to start tinkering on your own.
In chapter 4 we get down to business with a step-by-step guide to building the Replica I kit. While advanced readers may want to use chapter 7 and the included software to design their own board, the novice will be better served by having a working replica with which to experiment while reading the rest of the chapters. Builders who run into trouble with the kit can fall back on the skills they learned in chapter 3 to diagnose the problem or may ask for guidance on the Apple I Owners Club forum at applefritter.com.
The kit assembled, it's time to learn a bit of programming. Chapter 5 is a typical introduction to programming in BASIC, but Woz's implementation of BASIC for the Apple I contains a lot of idiosyncrasies, making this chapter a valuable reference for any Apple I programmer. Chapter 6 teaches the reader how to program in assembly. This chapter explains how to use a cross-assembler and introduces the (MOS 6502) processor's assembly instructions through exercises and sample programs.
The final chapter, Understanding the Apple I, draws together everything learned in previous chapters to examine how the replica really works. Memory addressing, interactions with the bus, the functions of the processor, and in/out are all discussed. The beginner will come away from this chapter with a basic understanding of each chip on the replica's circuit board. More advanced readers will have all the information they need to make their own modified replica circuits.
The Replica I kit described in this book can be purchased from Briel Computers for $119 (a bare-bones kit is available for $60). For advanced builders, Briel sells just the specialized chips (programmed EEPROM, etc.) for $30. The book's CD includes a full version of McCAD EDS SE 400, the best schematic capture and pcb layout software for the Mac. The Replica I's schematics, pcb layout, and fabrication documents are all included on the CD. Send the included gerber files to a pcb manufacturer and get your own prototypes made or modify the schematics to design your own custom boards.
McCAD EDS SE 400 is an excellent piece of software which I worked very hard to get included with the book. The full EDS-1 package retails for $1495 (the book includes a coupon for 50% off any McCAD product, by the way). This special edition of the McCAD software was written exclusively for inclusion with Apple I Replica Creation and is not available from any other source. The SE 400 version of McCAD EDS includes all the features of the full version, but limits the design's complexity so you can't design anything much more complex than a typical 8-bit microcomputer. You'll be hard pressed to find a similar software suite for under $500. The interface is without equal. While evaluating the software, I got into an argument with a McCAD programmer over the proper layout of the buttons in one of the dialog boxes, each of us backing up our position with extensive references to the Apple Human Interface Guidelines. He won (but only on a technicality!). These guys take user interface very seriously and I'm happy to say I've never used a more intuitive design package. The McCAD package is Mac OS X native, but also compatible with Mac OS 9. If you don't have a Mac, you may want to consider picking up an old $50 iMac just for this software. PC users might want to try running it in Basilisk.
Anybody interested in learning more about Apple I Replica Creation is welcome to visit my website, Applefritter. There you'll find the Apple I Owners Club and various user-contributed projects. Stop by and feel free to ask questions. We have the Apple I Owners Club forum for discussion of the Apple I and a McCAD support forum for those who have questions about the software. If there's anything you'd like to know about the book, don't hesitate to post.
Contents of this Book Include…
1: The History of the Apple 1
2: Tools and Materials
3: Digital Logic
4: Building the Replica
5: Programming in BASIC
6: Programming in Assembly
7: Understanding the Apple I
Appendix A: ASCII Codes
Appendix B: Operation Codes and Status Register
Appendix C: OpCode Matrix
Appendix D: Instructions by Category
Appendix E: Hacking Macintosh
Appendix F: Electrical Engineering Basics
About the Authors
Tom Owad is a Macintosh consultant in south-central PA and the D.C. area and vice president of Keystone MacCentral. He serves on the board of directors of the Apple I Owners Club, where he is also webmaster and archivist. Tom is owner and Webmaster of Applefritter, a Macintosh community of artists and engineers. Applefritter provides its members with discussion boards for the exchange of ideas and hosts countless member-contributed hardware hacks and other projects. Tom holds a BA in computer science and international affairs from Lafayette College, PA
John Greco (Technical Editor) is a professor of electrical and computer engineering at Lafayette College, where he has taught digital circuit and system design for 28 years. He holds a Ph.D. in electrical engineering from the City University of New York. In addition to teaching there and at the University of Petroleum and Minerals in Saudi Arabia, he has worked for GTE-Sylvania and has performed consulting work for (the former) Bell Laboratories and Moore Products.
Steve Wozniak, Foreword, A Silicon Valley icon and philanthropist for the past three decades, Steve Wozniak, Founder, Chairman and CEO of Wheels of Zeus (wOz), helped shape the computing industry with his design of Apple's first line of products the Apple I and II and influenced the popular Macintosh. For his achievements at Apple Computer, Steve was awarded the National Medal of Technology by the President of the United States in 1985, the highest honor bestowed America's leading innovators.
In 2000 Steve was inducted into the Inventors Hall of Fame and was awarded the prestigious Heinz Award for Technology, The Economy and Employment for “single-handedly designing the first personal computer and for then redirecting his lifelong passion for mathematics and electronics toward lighting the fires of excitement for education in grade school students and their teachers."
Making significant investments of both his time and resources in education, Wozniak “adopted" the Los Gatos School District, providing students and teachers with hands-on teaching and donations of state-of-the-art technology equipment. Wozniak founded the Electronic Frontier Foundation, and was the founding sponsor of the Tech Museum, Silicon Valley Ballet and Children's Discovery Museum of San Jose.
Steve is currently a member of the board of directors for Jacent, a developer of cost-effective telephony solutions, and Danger, Inc., developer of a end-to-end wireless Internet platform.