Personal Computer Museum, Canada's Videogame Museum

Hobby Computers of the 80's (cont'd)

By Jim Butterfield

©2005 (shown here with permission)

KIM 1 Computer VIII. The KIM-1

My first microcomputer - other than a logic device powered by rubber bands that I had constructed years before - was the MOS Technology KIM-1. KIM stands for "Keyboard Input Monitor", which was the operating system of this tiny single-board machine.

The "engine" of the KIM-1 is a 6502 microprocessor. This chip was designed by a group of ex-Motorola employees, who took the design of the Motorola 6800 and introduced new concepts and improvements. Leading the team was Chuck Peddle, a name you'll hear again in this presentation.

The 6502 was a late arrival into the early microprocessor world. Motorola and Intel chips had already gained acceptance; and even though the 6502 would outperform them, its merits were not immediately recognized. So MOS Technology priced the chip well below the competition: the 6502 was $25 in single unit quantities; competitive chips were around $150 and had to be ordered in batches of 100.

After the 6502 was completed, and legal disputes settled, MOS Technology decided that they should produce an "engineering sampler" board, which would show what the chip could do. They populated the board not only with microprocessor, RAM, and input/output; they also added a teletype interface, an LED display, a 20-key keypad, a facility for audio output and input (to save programs), and an operating system called KIM. And the board was factory-assembled; all you had to do was to add a power supply and you had a complete system.

Peter Jennings Here's the important part: because the board came pre-assembled, everyone had exactly the same system. For the first time, you could swap programs with other users and be confident that they would work without being "touched up" to fit the system.

I wrote a few programs - games, amusements, utilities - and wrote MOS Technology to see if anyone wanted them. They wanted them for themselves in order to demonstrate the KIM-1, and had also heard from a fellow in the Cleveland area who was starting a newsletter. And thus began "Kim User Notes", edited by Eric Rehnke.

The newsletter acquired hundreds of subscribers. MOS Technology must have been amazed to see this intended engineering prototype become a popular home gizmo. In time, it also became widely used as a training device.

About that time, I heard from a young fellow who worked at Honeywell who said he was working on a program for the KIM-1. His name was Peter Jennings, and his project was to write a chess-playing program in the KIM's tiny 1K of RAM. He did it, too. In these days of gigabyte memory, it's sometimes refreshing to think that Peter could play chess with only a little over 1K ... even if it didn't play at a grandmaster level. Peter later went on to be one of the creators of code for Visicalc, the first microcomputer spreadsheet program.

First Book of KIM IX. Publications, and The First Book of KIM

Meanwhile, there had been a few personal-computer publications. During his time with a minicomputer firm, David Ahl had gathered together various games that users had contributed, and published "101 Basic Games". On the west coast, Bob Albrecht had formed a group called "People's Computer" and had produced a similar volume entitled "What To Do After You Hit Return." In both books, the programs were supplied in the language Basic. They could be played on time-sharing systems, or Basic could be fitted to those computers that had enough memory - not very many of them in the early days.

Meanwhile, we KIM-1 users were contributing lots of programs to be printed in KIM User Notes. I suggested to another user, Stan Ockers, that perhaps we should bundle them together and put them into a book. The editor of the Notes, Eric Rehnke joined us in the enterprise and we privately printed The First Book of KIM.

As best I recall, we estimated our market at about 600 copies. We printed 2,000, sold about 1,000, and the remaining copies burned up in a garage fire. There was still demand for the book; people got mad at us when we said we had no more copies. So a publisher picked up the demand, and many thousands more were sold. There were also two editions printed in Germany, one authorized and one pirated. The authorized publisher never sent any royalties; the pirate publisher sent us secret payments. Go figure.

Jack Tramiel X. Commodore stumbles into the computer market

In late 1976, we heard that MOS Technology had been acquired by a firm called Commodore, which was known for making office furniture and calculators. There was to be a new microcomputer system called the PET.

The KIM-1 thus became a Commodore product, which is why I sometimes say that I programmed Commodore computers before they made computers.

Jack Tramiel was the founder of Commodore Business Machines. A former inmate of Auschwitz, Tramiel had started out with a part-time typewriter repair shop in the Bronx, supplemented by driving a taxi. In 1962, he moved to Toronto and set up a typewriter manufacturing business. He soon switched to calculators, and these devices soon made the transition from mechanical devices to electronics.

In October 1976, Tramiel took over MOS Technologies, which he perceived as a manufacturer of display devices and semiconductors. He got more than he bargained for. He also got Chuck Peddle, the designer of the 6502 chip. And Peddle was determined to build a home computer.

Peddle had taken a look at a prototype version of the Apple ][, and had wondered if Commodore should buy the company. He eventually decided that Commodore should build a home computer of their own design, and quickly talked Tramiel into it. An early model of the PET was shown to Radio Shack, in the hopes that they would sell the unit; but Radio Shack, in turn, opted to build their own home computer.

Commodore had undergone some trauma in its organization and financing. As part of a new corporate financing deal, corporate headquarters was moved to the Bahamas, and administrative offices were set up in the Philadelphia area. But Tramiel's heart apparently remained in Toronto. The corporate airplane - the PET jet - was often to be seen in a hangar at Pearson airport during the many years that followed.

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