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MCM Model 70 mocrocomputer, made by Micro Computer Machines, 1974

The MCM/70 was a pioneering microcomputer first built in 1973 in Toronto, Ontario, Canada[1][2] and released the next year, making it one of the first microcomputers in the world, the second to be shipped in completed form, and the first portable computer. The MCM/70 was the product of Micro Computer Machines, one of three related companies set up in Toronto in 1971 by Mers Kutt. It is considered by some historians to be the first usable personal microcomputer system.[3][4][5]

Early history[edit]

Kutt, a professor of mathematics at Queen's University in Kingston, Ontario during the late 1960s, noted that the efficiency of computer users there was hampered by the long wait times involved in submitting programs in punched card form to be batch-processed by a shared mainframe. In 1968, Kutt and Donald Pamenter started a firm, Consolidated Computer Inc.,[6] and began to produce a data-entry device known as "Key-Edit".[7] This was a low-cost terminal, with a single line of display, which bypassed the need for key-punching.

In 1971, Kutt, no longer part of CCI, began planning a machine to support software development in the recently developed APL programming language. APL was best programmed using a custom keyboard and these were in very short supply at the time. He initially called his design the "Key-Cassette"; similar in design and concept to Key-Edit, it would offer editing capability and support for either two cassette decks or one cassette and an acoustic coupler to upload programs to other machines.[7]

MCM Model 70 microcomputer 1974 APL keyboard

The original design resembled a desktop electronic calculator; Kutt's notes of the era showed his intention to use the cover and display from an existing calculator with a modified power supply, and to include a small keyboard with 32 keys, and a display made up of either 13 or 15 segmented LEDs.[7] Kutt also created a company, Micro Computer Machines, which would later manufacture the devices.


Through his acquaintance with Intel founder Bob Noyce, Kutt had been following Intel's work on the 1201, an 8-bit microprocessor later renamed the Intel 8008. The processor was slated for to be completed in late 1971, but its release was delayed until spring. In December 1971, Kutt incorporated a technology development company, Kutt Systems. He signed an agreement with Intel to supply an Intel 4004, a SIM4- 01 development system, supporting chips from the MCS-4 chipset, and an MP7-01 EPROM programmer to his new company. This equipment was used for early development work until the 8008 was available.[7]

Kutt hired programmer Gord Ramer, and the two began work on developing Kutt's concept. In May 1972, Kutt Systems received one of the earliest SIM8-01 kits. The team, now including hardware engineer José Laraya, software engineer André Arpin, and two APL programmers, Don Genner and Morgan Smyth, started to build what was now known as the "M/C", for "microcomputer". By that time the design had expanded to include a complete keyboard, a "chiclet" design similar to the ones used on early models of the Commodore PET, and a Burroughs Self-Scan 32-character display.[7] Unlike the earlier "Key-Edit" system, the M/C would allow both entry and execution of APL programs.

Dissatisfied with the SIM8 equipment, the Kutt Systems staff built a motherboard from scratch, including an Omniport, an 8008-expansion bus. Meanwhile, work on porting an APL interpreter to the system continued, using an 8008 emulator written in Fortran known as "INTERP/8". The system, mocked up in breadboard form, was first displayed publicly on 11 November 1972 at the Kutt offices in Kingston, Ontario.[8] In May 1973, the same system was shown at the APL Users’ Conference in Toronto, now encased in fibreglass.[9] The completed design, in its new injection moulded case, was demonstrated for the press on 25 September 1973.[10]


The MCM/70, manufactured by Micro Computer Machines in Kingston, was encased in a wedge-shaped metal box about half a metre on a side, with a keyboard at the front, a cassette tape recorder(s) in the middle,[11] and a tiny one-line plasma display at the top. The MCM/70 resembled a Commodore PET with the monitor removed and replaced with the smaller display.

An APL interpreter was built into the ROM,[12] soc and the machine included a battery which allowed it time to save the "workspace" automatically when it was turned off. The MCM/70 weighed 20 pounds (9 kg)[13] and shipped with up to 8 kilobytes of RAM and zero, one or two cassette drives.[14]


The first complete systems were shipped to dealers in the autumn of 1974. The basic unit, model 720 with an 80 kHz 8008,[5] 2 kB RAM[15] and no cassette drive sold for $4,950 Canadian (at the time the dollar was about par to the US dollar).[16] The "fully loaded" 782 with 8k and two drives was $9,800, and was the only model that really sold.

At the time, the machine was already officially being referred to as a "personal computer". The first manuals contain a personal note from Kutt to future customers, "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."[17]

The MCM/70 was sold mainly to companies and government institutions with the need to make complex calculations and mathematical analysis. MCM's customers ranged from hospitals and insurance companies to NASA and the US Army.[18]

Later development[edit]

In 1975 the computer was re-released with no changes as the MCM/700; also released that year were a punched card reader, plotter and a number of programs. The MCM/800 followed in 1976; it was faster, included 16k RAM, and included the ability to drive an external monitor. Virtual memory was supported on all of the machines, although using cassettes for storage made it somewhat impractical.

1978's MCM/900 was faster yet, included 24 kB RAM, and an included a monitor. The MCM/1000, also called the MCM Power was a re-packaged /900, and was later re-packaged again as the MCM MicroPower. The real change for the /900 and /1000 was to support the HDS-10 disk server, which included an 8.4 MB 8 inch Shugart hard drive, an 8-inch floppy disk drive, and a 64 k Zilog Z80 to control it. Up to 8 /900's /1000's could be plugged into the HDS-10.

Demise and legacy[edit]

By the late 1970s, after selling several hundred units,[14] MCM was facing competition from a number of home computer systems with the same sort of power as their own machines. Although another more advanced microcomputer, dubbed "A*2", was in the design phase, the funding needed for rapid development was not available. By 1983 the company was no longer in operation.

Rights to the in-progress A*2 design were sold to Ampex. They worked on the design for about a year before also shutting down development. This machine, called "Sysmo", was sold in France by Sysmo company from 1975. This start-up was funded in Paris by Michel Carlier, an engineer who had invested also in MCM, with his own capital. However, the machine was sold for management applications while it was programmed with a complex scientific language (APL) much better adapted to scientific and technical fields; Sysmo company filed for bankruptcy in 1978. The stock of MCM/Sysmo was bought by French company Generale d'Electricite (later Alcatel) for its own use because of the product's mathematical computation features.[citation needed]

In 2001 York University professor Zbigniew Stachniak published a book about the development of the MCM/70, titled Inventing the PC: The MCM/70 Story.[19] A collection of papers, illustrations and hardware related to the device have been included in the York University Computer Museum.



  1. ^ "How Toronto invented the PC, then forgot about it." Spacing, April 15, 2015 | By Chris Bateman
  2. ^ "Idea nation". Canadian Business, Dec 25, 2006 Andy Holloway
  3. ^ Caroline Alphonso, "Canadian hailed as father of PC", Globe and Mail, 20 September 2003
  4. ^ Bernadette Hlubik Schell (2007). The Internet and Society: A Reference Handbook. ABC-CLIO. pp. 145–. ISBN 978-1-59884-031-5. 
  5. ^ a b John Craig (13 October 1980). "Viewpoint". InfoWorld. InfoWorld Media Group, Inc.: 9–. ISSN 0199-6649. 
  6. ^ Executive. Volume 19. Southam Business Publications. 1977. p. 38. 
  7. ^ a b c d e Stachniak 2011, pg. 9
  8. ^ Stachniak 2011, pg. 10
  9. ^ Stachniak 2011, pg. 11
  10. ^ Stachniak 2011, pg. 6
  11. ^ Electronics. Volume 46. McGraw-Hill Publishing Company. October 1973. p. 52. 
  12. ^ "Judge dismisses Canadian IT pioneer’s Intel patent suit". IT Business, Dave Webb, March 16th, 2005
  13. ^ Executive. Volume 15. Southam Business Publications. 1973. p. 28. 
  14. ^ a b "INNOVATION NATION". Steve Brearton, Globe and Mail, Aug. 26, 2005
  15. ^ "Pc Pioneer Plans Another Try". Sun Sentinel, October 6, 2003|CHRISTINE WINTER
  16. ^ Jon Peddie (13 June 2013). The History of Visual Magic in Computers: How Beautiful Images are Made in CAD, 3D, VR and AR. Springer Science & Business Media. pp. 178–. ISBN 978-1-4471-4932-3. 
  17. ^ Stachniak 2011, pg. 12
  18. ^ Zbigniew Stachniak, "The MCM/70 Microcomputer", CORE 4.1 - The Computer History Museum, September 2003, pg. 6-12
  19. ^ David C. Brock, "Inventing the PC: The MCM/70 Story (review)". Technology and Culture Volume 53, Number 2, April 2012 pp. 518-519 | 10.1353/tech.2012.0077


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