r1temanMAR2009 (EN)

replica I Setup and Users Manual Setup and Users Manual Setup and Users Manual Setup and Users Manual MARCH 2009 TE EDITION Briel Computers Briel Computers Briel Computers Briel Computers 5392 Cornell Blvd North Ridgeville, OH 44039

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Replica 1 TE Users Manual All materials, schematics, and hardware designs provided without any warranties. Although this material has been carefully examined, Briel Computers takes no responsibility for any errors in printing. Version 3.0 Published by Briel Computers 5392 Cornell Blvd North Ridgeville, OH 44039 USA Copyright 2009 Briel Computers. All rights reserved. Printed in the United States of America.

Except as permitted under the Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher, with the exception that the program listings may be entered, stored, and executed in a computer system, but they may not be reproduced for publication. © Briel Computers 2007 page 2

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Replica 1 TE Users Manual Forward Forward Forward Forward How the replica 1 came to be Thank you for purchasing your replica 1 computer. I take pride in every kit and assembled replica that is shipped and my goal is that all kits and assembled boards work as designed. In early 2001 I was an avid collector of vintage computers. I had started with an Apple IIe because it was close to my first computer the Apple IIplus. I, like many people who get the urge to relive the yesteryears of computing looked to eBay to find my past. After receiving my first computer I found myself wanting a monitor, a disk drive, anything to make it fully functional.

I didn’t just want a mantle piece; I wanted to actually use my vintage machine. After spending some time with my Apple I remembered other computers I had seen in magazines but couldn’t afford at the time. I little searching and I was able to start a nice little collection of home computers. I was addicted to vintage computing and collecting everything I could get my hands on. I was really proud of the fact that every machine I owned, not only worked but I had software to run on them. I was fast becoming an expert in the area of software conversion from the modern computer realm back to actual vintage media like 5 ј” disk.

Feeling proud that I had a nice collection going I stumbled upon the www.applefritter.com website. I felt pretty versed with apple II hardware and I noticed a small forum there and poked in to read some of the posts. I didn’t see anything out of the ordinary but I noticed a subject right above the Apple II section labeled Apple I. Well, I had never seen an Apple I and had only herd the stories like most people about how Woz and Jobs started Apple Computers from their garage. I had to read more. I quickly learned that only about 50 Apple 1’s remained in existence from about 200 boards and they were highly collectable and way out of my price range.

I read a post where people talked about making a replica but nobody was really stepping up to the plate. I have an education in engineering so I decided to take a look into the Apple 1 hardware. In March 2002 I wrote to the Applefritter forum requesting some information on the Apple 1 and I informed the group of my intentions. I was well received and many former and current owners of Apple 1 computers gave me information and documentation to get started. With manuals and emails from owners in hand, I looked over every inch of the Apple 1. I quickly decided not to use all the original components from the Apple 1 due to their lack of ability.

Although there are chip suppliers that carry surplus components, their prices and minimum orders are just out of the question. This left me with a decision that many people questioned. I could have made the replica 1 look like the Apple 1 but in the spirit of Woz, I choose to go with more modern components and reduce the chip count as low as possible. I quickly found that I could interface 32K of RAM with no address decoding. Simply using Address line A15 as the select line, I could activate the RAM chip with A15 off. So, if the replica 1 was looking anywhere in the address range 0000-7FFF A15 would be low and RAM chip select activated.

If the replica 1 was looking at address range 8000-FFFF A15 would now be high and the RAM chip select would be deactivated. I added some logic so that the access time of the RAM write cycle was only during PHI2 of the 6502’s clock. For this I used a 74LS00 NAND gate IC. I needed to invert the R/W signal and AND in PHI2. This required 2 of the 4 NAND gates in the IC. © Briel Computers 2007 page 3

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Replica 1 TE Users Manual My next step was to add some address decoding so the replica 1 accessed the I/O chip 6821 PIA and ROM at the same addresses the Apple 1 used. I used a 74LS138 to decode addressing for both the 6821 and an 8K EEPROM. I also made sure that the space for BASIC (E000-EFFF) was EEPROM so BASIC could be stored in ROM. I now had a core CPU section replicated from the Apple 1. I still had no video section and I needed to build a prototype. After some delays I finally built a prototype on wire-wrap and tested it. It didn’t work. I needed to troubleshoot the board but my free time was very hard to come by and the replica sat on the shelf for a few months.

In November of 2002 I received an email from Leander Kahney of Wired Magazine. He had been reading on the replica project and wanted to interview me. My first reaction was, “Why me?” I had no idea the cult following that Apple had. I really was fond of Apple since the beginning but Apple has such loyal owners and they love everything that involves the history. So, here I am on the phone with Leander as he is asking me questions about why I am doing the project, and when will it be completed and what will I be selling these for? What? I didn’t have the heart to tell him that the project is on the self, that I have no idea what to sell these for even if I had a working version.

Little did Leander know that because of him, the replica 1 was pulled off the shelf and completed. I started from scratch, and created a breadboard version of the replica 1. This time it worked… Sort of… Well, the I/O chip, the 6821 was sending binary code for a “\” which means that the replica was seeing a reset and the Woz monitor was trying to output a “\” to a TV monitor. Now I needed a video solution. Right after the Wired article was released, I received an email from Greg Glawitsch. He stated his interest in the project and said that he had a “down and dirty” solution to the video problem.

His answer was to use a microcontroller to output TV text like the video terminal section of the manual. He offered to help by writing the firmware to do this and it would only require a couple external IC’s to help the microcontroller. Wow, 3 chips to do what took about 24 on the Apple 1. This was perfect. And with some work with Greg, we had a working video section. In August 2003 the first of the replica prototypes were being made. I didn’t have a name for the board yet and simply called it A1 replica. I also just put my initials on the board with the year 2003. Shortly after my first prototypes were built, I created Briel Computers.

At this stage my old high school friend Chris contacted Woz through his webmaster asking for permission to use the Apple 1 code. His approval of the project prompted another Wired article. In October 2003, the first replica 1’s was being built and thus completing a 20 year old dream to design and sell my very own computer. Thanks to Woz for being such a strong influence and great guy to give the ok for this project. Vince Briel © Briel Computers 2007 page 4

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