The MCM/70 is a pioneering microcomputer first built in 1973 in Toronto, Ontario, Canada, and released the next year. This makes 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.

Early history

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 for batch processing by a shared mainframe computer. In 1968, Kutt and Donald Pamenter started a firm, Consolidated Computer Inc., and began to produce a data-entry device named Key-Edit. This was a low-cost terminal, with a one-line display device, which bypassed the need for keypunching.

In 1971, Kutt, no longer part of CCI, began planning a machine to support software development in the recently developed programming language APL. APL was best programmed using a custom keyboard and these were very rare at the time. He initially named his design the Key-Cassette; similar in design and concept to Key-Edit, it would offer editing ability and support for either two cassette decks or one cassette and an acoustic coupler to upload programs to other machines. In May 1973, the same system was shown at the APL Users' Conference in Toronto, now encased in fibreglass. The completed design, in its new injection moulded case, was demonstrated for the press on 25 September 1973.

Specifications

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 compact audio cassette tape recorder(s) in the middle, and a one-line plasma display at the top. The MCM/70 had a one-line display and alphanumeric keyboard, and optionally had a second tape drive. It resembled desktop calculators of the time, such as HP 9830A.

An APL interpreter was built into the read-only memory (ROM), 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) and shipped with up to 8 kilobytes of RAM and zero, one, or two cassette drives.

Release

The first complete systems were shipped to dealers in the autumn of 1974. The basic unit, model 720 with an 800 kHz 8008, and no cassette drive sold for $4,950 Canadian (at the time the dollar was about equal to the US dollar). The fully equipped model 782 with 8 KB and two drives was $9,800, and was the only model that sold well.

At the time, the machine was already officially being called 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."

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 United States Army.

Later development

In 1975, the computer was rereleased with no changes as the MCM/700. A collection of papers, illustrations and hardware related to the device have been included in the York University Computer Museum.

See also

  • SCELBI
  • Mark-8
  • Micral
  • Datapoint 2200

References

Notes

Bibliography

  • York University Computer Museum – Includes several items from the MCM company
  • old-computers.com website info and pictures of MCM systems