“The complexity of the large computer machines and the complexity of the special computer languages…has till now prevented the general public from using computers directly themselves. But the simplicity of the MCM/70 and its associated computer language…make personal computer use and ownership a reality….Enjoy the privilege of having your own personal computer.”  —The MCM/70 Introductory Manual, 1973
Programming “was really slow and….every time we programmed, Don [Genner] used to smoke one cigarette and say, ‘That’s how long it takes to program a chip.’ He smoked one cigarette, and when he finished, [the chip] was programmed.” —José Laraya, MCM Engineer


In early 1972, a small group of computing professionals came together in Kingston, Canada, to design a novel computer system based on emerging microprocessor technology. The result of their work at Micro Computer Machines Inc. (MCM) was the MCM/70 personal computer. The following article details the early stages in the development of the MCM/70 microcomputer. The article is based primarily on development notes authored by Mers Kutt, the first president of MCM.

These notes, most likely written between February and May of 1972, are among the oldest records chronicling the coming of the personal microcomputer. Quotations by Kutt, Gordon Ramer, José Laraya, and Morgan Smyth were obtained through interviews by the author between March, 2001, and December, 2002.  Kutt’s notes and recordings of the interviews currently reside at the York University Computer Museum in Toronto, Canada.

Announcement of the MCM/70 during the press conference at the Royal York Hotel in Toronto, September 25, 1973. From left: Mers Kutt, Gordon Ramer, Ted Edwards, and Reg Rea. Source: Canadian Datasystems, October 1973, p. 49.


The MCM/70 computer, designed by MCM between 1972 and 1973, is possibly the earliest example of a microcomputer manufactured specifically for personal use. From the hardware and software engineering points of view it does not have much in common with early hobby computers, such as the MITS Altair 8800 or Apple I, except that these computers were microprocessor-based. By the time the Altair 8800 kit was offered to hobbyists in early 1975, with its 256 bytes of RAM memory and no high-level programming language capability, the MCM microcomputers were providing inhouse APL (A Programming Language) support for applications ranging from engineering design, modeling and simulation, to investment analysis and education. By the time the Apple I board was offered for sale in 1976, the MCM machines were being used by Chevron Oil Research Company, Firestone, Toronto Hospital for Sick Children, Mutual Life Insurance Company of New York, Ontario Hydro-Electric Power Commission, NASA Goddard Space Flight Center, and the U.S. Army, to name just a few MCM customers.

The official announcement of the MCM/70 came on September 25, 1973, in Toronto. Two days later, it was unveiled in New York and the following day in Boston. An early prototype had been demonstrated to the APL community in May of 1973 during the Fifth International APL Users’ Conference in Toronto. Another prototype was touring Europe in August and September of that year and was showcased by the MCM team in Holland, Germany, Switzerland, France, Italy, and the U.K. Other prototypes of the machine included an early refinement of the Intel SIM8-01 development board, a rack-based wirewrapped system, a desktop bare-bones system, and even a cardboard mockup.

The MCM/70 desktop bare-bones system. 3Dmodel created by André Arpin.


In the fall of 1971, just after he left his first company, Consolidated Computer Inc., Canadian inventor and entrepreneur Mers Kutt decided to develop a small desktop personal computer that could be programmed in APL. Kutt followed technological developments and market trends in the semiconductor industry closely. He personally knew Bob Noyce, then the CEO of Intel Corporation, and was meeting with Intel marketing staff and participating in Intel promotional seminars. He had a good knowledge of the technical specifications and of the developmental progress of Intel’s first 8-bit microprocessor—the 1201, later renamed the 8008. For Kutt, the near completion of the 8008 chip in late 1971 was a technological trigger point urging him to move ahead with his personal microcomputer project.

In the beginning, there were just two: Mers Kutt and Gord Ramer, whom Kutt recruited to work on the software aspect of the project. Before joining forces with Kutt, Ramer was the director of the Computing Center at St. Lawrence College in Kingston. Before that Ramer had worked at York University, then on the outskirts of Toronto, and developed the York APL dialect of Iverson’s APL language. His experience with space-efficient York APL was critical for the writing of the MCM/APL interpreter, which Ramer initiated even before the 8008 chip was available in quantity from Intel.

Mers Kutt speaking at York University, Toronto, October 2001
Photograph by Z. Stachniak

The small company was incorporated on December 28, 1971, under the name Kutt Systems Inc. On the same day, Hank Smith, who was in charge of Intel’s Micro Computer Systems Group, signed a shipment invoice for a SIM4- 01 development system, an MCS-4 chip set, and an MP7-01 EPROM programmer, together valued at $1,231, to be delivered to Kutt at no charge. The second shipment from Intel, on May 23, 1972, delivered a SIM8-01 development board and an MP7-02 programmer. By that time, the company had hired, among other people, a hardware engineer by the name of José Laraya, APL programmers Don Genner and Morgan Smyth, and software engineer André Arpin, whose main job would be to develop the virtual memory system for the MCM/70 computer.


The company was aiming at a small, microprocessor-based desktop computer that would be affordable, as easy to use as a hand-held calculator, and functionally as powerful as a mainframe computer running APL. Nothing similar had ever been built before. At the time, in December 1971, the news of a CPU on a single chip was only about one month old. Furthermore, APL interpreters were not even available for minicomputers.

The size, price, and usability targets set by Kutt Systems for its microcomputer focused the attention of the company on the calculator market. “The world was full of calculators,” recollects Kutt. “They made a real Big Bang.” In his notes, Kutt entered, “Try and use existing calculator cover, display, modify power supply, and replace keyboard.” Indeed, off-the-shelf calculator components could save the company money. For instance, to package the computer into a case that would match the design elegance of a calculator cover, the case would have to be manufactured using the injection molding technique. But that was expensive: a good quality mold with sharp corners would cost around $25,000.

The Key-Cassette drawing. Source: M. Kutt’s notes

Kutt’s notes provide an early glimpse of the “computer of the future.” His drawing, entitled Key-Cassette, is among the oldest preserved sketches of a microcomputer to be manufactured for the consumer market. The name “Key- Cassette” most likely derives from “Key- Edit,” the name of the data entry system manufactured by Kutt’s former company, Consolidated Computer Inc. The drawing depicts a case in the style of a typical desktop calculator of that time. The lower part of the front panel hosts a built-in keyboard and the top part depicts a single cassette drive on the right and either an acoustic coupler or the second cassette drive on the left. A small display and some switches are placed in the middle of the panel.

A fragment of the Key-Cassette’s keyboard. Source: M. Kutt’s notes

Page two of the MCM/70 User’s Guide introduces the keyboard layout.

The annotated drawing provides enough information to grasp the basic operations of the Key-Cassette. The small 32-key keyboard of the Key-Cassette would allow the user to enter all the alphanumeric characters as well as the APL and special function symbols. To achieve such a degree of compactness, each key was designed to enter up to 5 symbols (using a combination of key strokes). The symbols on the keys would be color coded to distinguish between the symbols that can be entered directly (red symbols in the center of the keys) and those that could be entered via a combination of key strokes (black symbols placed in the corners of the keys).

The one-line display of the Key-Cassette would allow the user to view a single line of APL code, a computer output, or an error message. Using the rotate keys “→” and “←”, the displayed information could be scrolled left and right to fully reveal its contents. Using the roll keys “↓” and “↑”, one would scroll through the lines of APL code. The sketch of the Key-Cassette is augmented with two drawings of possible segmented display elements: one comprised of 13 display segments and the other of 15 segments. Finally, the tape cassette drives were to provide external storage.

The production model of the MCM/70 would be equipped with a more “user-friendly” APL keyboard (layout modeled after the keyboard of the IBM 2741 terminal), with a one-line plasma display and up to two digital cassette drives providing over 100KB of storage each. Only the sides of the case would be injection molded, while the rest of the case would be made of cheaper aluminum.


Kutt’s notes contain a detailed analysis of Intel’s MCS-4 chip set, the 8008 processor, the SIM8-01 development system, and the MP7-02 programmer. Kutt looks at the technical specifications, pricing, and second sourcing for electronic components. He looks at Intel itself, its marketing activities.

In April of 1972, Kutt paid Intel a visit  and learned from Bob Noyce and Hank Smith about the status of the 8008 chip, the availability of the SIM8-01 development board, and its supporting software. He inquired about the possibility of Intel manufacturing custom CPU boards for the MCM computer. In his notes, Kutt entered that standard 8008 prototyping boards, ones that could be used to prototype and test an MCS-8 based system without building his own board, would have a “tremendous impact.”

A month later, Kutt received the SIM8-01 board from Intel and gave it to José Laraya for the evaluation and the estimation of its potential for growing an APL machine out of it. Laraya recalls: “Mers brought it [the SIM8-01] in and said, ‘Here, see what it does.’ It was really computing, it really did things, one little chip.” The experimentation with the SIM8 board concentrated on interfacing with various devices (such as the teletype) and on the use of the MP7-02 programmer for the purpose of burning Ramer’s APL interpreter into the EPROM chips.

But this early attempt at building a microcomputer, now called the M/C prototype in the notes, was a disappointment. Kutt wrote that the
machine “is useless as is,” and has to be “drawn up, rewired, and debugged.” In the end, Laraya decided to abandon the SIM8 approach and, instead, was determined to build his own hardware from the ground up. He remembers thinking, “OK, this [SIM8-01] is fine, great, interesting, works with teletype…But now, let’s build something serious.’’ Laraya adds, “Mers got the chips and on the basis of that I developed the rack version….It was very fast from the time we had the [SIM8-01] development board.”

Laraya modularized the design of the M/C prototype. One card included the 8008-based CPU as well as the display and the keyboard interfaces. Another card contained memory. There was a specially designed APL keyboard, with the soft character generator, and a small plasma display (Burroughs Self-Scan 32-character display). The production model would have one more board with the cassette controller and the Omniport interface on it (to connect a variety of peripherals via the Omniport connector at the back of the machine).

The rack prototype of the microcomputer was good enough for Ramer and Genner to start porting their APL interpreter into it. On November 11, 1972, the prototype was demonstrated to shareholders during the Special General Meeting of the Shareholders of Kutt Systems in Kingston, Ontario. During that meeting a motion was passed to change the name of the company to Micro Computer Machines


In the early 1970s, APL was only available on mainframe computers. The development of an APL interpreter and the memory management system for an 8008-platform characterized by low speed, restricted instruction set, and small memory addressing space was the most challenging aspect of the personal computer project at MCM. The team that developed the interpreter had worked together before. In late 1960s, Gord Ramer designed a dialect of the APL/360 language that he named York APL. He implemented the language with the assistance of Don Genner while both Ramer and Genner held positions in the Computing Center at York University. J. Morgan Smyth was among the first users of the York APL and he was frequently commuting between his work place—Ryerson Polytechnic Institute in Toronto—and York University to discuss the implementation issues of York APL with Ramer and Genner. At MCM, the trio would develop one of the first high-level language interpreters for a microprocessor: Ramer would design the language, Genner would implement it, and Smyth would document it in an excellent MCM/70 User’s Guide published by MCM in 1974.

Morgan Smyth (left), Don Genner, and Gord Ramer (right) at York University, Toronto, October 2001
Photograph by Z. Stachniak

The work on the interpreter started in early 1972 even before MCM built any hardware that could be used by the software engineering group. Having only the specifications of the 8008 chip, Ramer and Genner used the IBM System/360 assembler to emulate the 8008. “The 360 assembler was written in such a way that you could use macros to generate code for any hardware,” says Ramer. “Thus [we] generated macros for each 8008 instruction and voila!” A similar emulator, the INTERP/8 (written in Fortran IV), was later available from Intel. It provided a software emulation of the 8008 chip along with some execution monitoring commands.

When the rack prototype of the microcomputer was finally working at MCM’s manufacturing facility in Kingston, the development of the APL interpreter could be done directly on the 8008-based hardware and the interpreter’s code could be burned into EPROMs using the Intel MP7-02 programmer. Programming “was really slow,” says Laraya, “and you had to program it by hand using switches….We had to put the code and set the switches and the addresses and hit ‘program’ [the EPROM]. Every time we programmed, Don [Genner] used to smoke one cigarette and say, ‘That’s how long it takes to program a chip.’ He smoked one cigarette, and when he finished, [the chip] was programmed.”

In his notes, Kutt sketches the directions for the development of the APL interpreter for the microcomputer. First, the basic, stripped-down version of APL/360 would be implemented. The description of an APL fragment that comprises single dimension vectors, some defined and some system functions, spans two pages in the notes. Then the interpreter would be extended in two directions to support the scientific and business utilization of APL. “When we came up with the APL [interpreter] for our PC,” says Kutt, “our prime target was to make it simple to use…so [the user] wouldn’t have to become embroiled in the little nitty-gritty things you have to look after in APL.” The full description of the MCM/APL interpreter for the MCM/70 computer appeared in the MCM/70 User’s Guide.


The notes disclose some urgency to prepare a viable demonstration of the M/C computer. Early demonstrations were vital to attract venture capital and finance the operations of the young company. Kutt sketches a “short-cut to demo” in his notes and estimates its completion at the early June of 1972.

The M/C demonstrator was to consist of a single CPU and memory board and a power supply packed into a desktop calculator-like case that featured a builtin keyboard and a small display. It was to be basic hardware with just enough software stored in ROM to demonstrate the way the 8008 could handle a subset of APL.

The Short-cut to demo drawing. Source: M. Kutt’s notes

It is unclear whether such a machine was ever constructed. However, a more refined portable prototype of the MCM/70 was built and shown during the Fifth International APL Users’ Conference in Toronto, in May of 1973. “I remember we had the fiberglass model there,” says Laraya. “It was heating up.” Ramer, too, remembers the event vividly: “The demo had to be interspersed with short talks to allow José [Laraya] to exchange the heat-sensitive parts and then restart the system for the next segment of the demo.”

With limited RAM and no external storage, that prototype was nothing but an advanced APL-based scientific calculator. However rudimentary, it did attract attention of the APL community and made it evident that in the near future high-level programming languages, such as APL, would be readily available on small desk-top machines. Other prototypes of the MCM/70, including one mounted in an attaché case and powered by batteries, were showcased throughout Europe and North America in the second half of 1973, attracting the attention of daily and technical press.

One of the most successful demonstrators that the company put together had, in fact, no hardware at all. “We had a cardboard mockup of the computer,” says Smyth. “It…was a small, slick little was just cardboard. And we went around to a law firm in downtown Toronto and met with the bunch of senior lawyers there….Mers was gonna try to get some venture capital.…These guys were quite old and, at one point [during Kutt’s presentation], actually the secretary came in with a can of candies….to perk ‘em up. And I thought, ‘man, we are wasting our time here.’”

Smyth continues, “And near the tail of our presentation, which went on for over two hours, …one of these guys said, ‘Now, just a minute. This contradicts what you said at the very beginning.’ I’m thinking, ‘What?’ They were paying attention and I was very impressed… We walked out of there with half a million dollars….It was…just cardboard….He [Kutt] is waving this around: ‘This is what it’s going to look like!’ You are talking about selling the future!”


The production model of the MCM/70 shared many technical features with the Key-Cassette and the M/C concepts. From its prototypes, the MCM/70 inherited a desktop design with built-in APL keyboard, a one-line plasma display, and cassette drives mounted on the front panel. The computer was powered by the Intel 8008 microprocessor and its ROM chips contained the MCM/APL interpreter.

But other features, not discussed in Kutt’s notes, also make the MCM/70 a truly unique piece of microcomputer engineering. The MCM/70’s 14KB of ROM contained not only the MCM/APL interpreter but also the cassette and virtual memory operating systems (called EASY and AVS, respectively). AVS, designed by André Arpin, used one of the cassette drives to provide virtual memory by swapping programs and data between the cassette and RAM. With virtual memory, the MCM/70 offered an excess of 100KB of memory. A power failure protection system built into the power supply of the computer allowed continuous operation by battery in the event of power failure. For extended power loss, the computer initiated an orderly shutdown: it automatically provided system back-up by copying the content of RAM to a cassette before shutdown. The system was automatically reinstated when power was restored and batteries were recharged.

The MCM/70. Courtesy of Harley Courtney
Photograph by Z. Stachniak

Kutt made some market analysis notes looking primarily at the IBM System/360 users who might benefit from a smaller and much less expensive
system. He calculated APL university prospects at around 15 in Canada and 75 in the U.S. And indeed, following the announcement of the MCM/70, many academics expressed interest in the MCM hardware: “APL is currently used in all of our introductory courses so that the potential for systems like yours at Yale is very high,” wrote Martin H. Schultz, Professor of Computer Science at Yale University, to MCM in November 1973. By 1976, an estimated 27.5% of the MCM systems sold in North America went to educational institutions.

The notes, however, do not make any reference to “personal computing” nor to possible marketing strategies aimed at promoting the personal utilization of MCM’s microcomputers. This is hardly a surprise as the notes were made in the very early stages of the development of the MCM/70. That situation would change with the publication of the first promotional documents by MCM in 1973. “It has been a combination of the complexity of the large computer machines and the complexity of the special computer languages,” reads the MCM/70 Introductory Manual published by MCM in 1973, “that has till now prevented the general public from using computers directly themselves. But the simplicity of the MCM/70 and its associated computer language (known as APL) make personal computer use and ownership a reality….Enjoy the privilege of having your own personal computer—It’s a privilege no computer user has ever had before the MCM/70….Good luck, and welcome to the computer age!”

It is difficult to explain unequivocally why the MCM/70 was not the commercial breakthrough to launch the personal computing industry. It is also difficult to estimate the number of MCM/70 computers sold worldwide or the scope of impact it had on the APL community and on the rise of personal computing. Even so, it was MCM’s historical role to show that with the advent of microprocessor technology, affordable personal computing was at our fingertips. It was not too farfetched to imagine that, “in the coming years the computer field is going to be made of millions of small computers and a limited number of large computers” (Mers Kutt, Boston, September 28, 1973).

Zbigniew Stachniak is an associate professor of computer science at York University in Toronto, Canada. His research concentrates on formal methods in artificial intelligence (automated reasoning, knowledge representation), on symbolic logic in computer science, history of computing, and history of logic.

The author extends his gratitude to the National Science and Engineering Research Council of Canada for supporting his research on MCM.


Chevreau, J. “The Third Coming of Mers Kutt.” Report on Business Magazine, November 1985, pp. 110-115.

Stachniak, Z. “The Making of the MCM/70 Microcomputer.” IEEE Annals of the History of Computing, May/June, 2003.
The MCM Collection at York University Computer Museum:
This article was originally published in "CORE 4.1 - The Computer History Museum" (September 2003). pp. 6--12.  It has been posted in this Web site with the permission of its author.



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