MCM/70

The MCM/70 was a pioneering microcomputer first released in 1973, making it one of the first microcomputers in the world, the first to be shipped in completed form, the first portable computer, and arguably the first truly usable microcomputer system. Nevertheless this machine remains virtually unknown.

Early History

The MCM/70 was the product of Micro Computer Machines, one of three related companies set up in Toronto in 1971 by Mers Kutt. Kutt had already started another firm, Consolidated Computer Inc., to produce a data-entry system, but had recently been squeezed out and was looking for new projects. Kutt had worked at Queen's University in Kingston, Ontario during the late 1960s where he saw the frustration of computer users who were forced to submit programs in punch card form to a shared mainframe. During 1971 and 1972 he received a number of Intel 8008 CPUs from Intel, intending to produce a usable desktop machine for university professors and students running the APL programming language, then the "new thing" in computer science.

By September 1973 his first design, the MCM/70, was complete, and was officially launched in 1974. The machine consisted of a wedge-shaped metal box about half a metre on the side, with a keyboard at the front, a cassette tape recorder(s) in the middle, and a tiny one-line plasma display at the top. The MCM/70 looks quite a bit like a Commodore PET with the monitor removed and replaced with the smaller display, and it would not be surprising if it served as the inspiration for the PET's later design.

APL was built in, and the machine included a battery that automatically saved the "workspace" when it was turned off. The MCM/70 weighed 20 pounds (9 kg) and shipped in a number of versions with various amounts of RAM and zero, one or two cassette drives. The basic unit, model 720 with an 80 kHz (yes, kHz) 8008, 2 kB RAM and no cassette drive sold for $4,950 Canadian (at the time the dollar was about par to the US dollar). The "fully loaded" 782 with 8k and two drives was $9,800, and was the only model that really sold.

Versions

The machine received only minor recognition, so in 1975 it was re-released with no changes as the MCM/700. Also released that year was a punch card reader, plotter and a number of programs. The MCM/800 followed in 1976 which 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.

1978s MCM/900 was faster again, included 24 kB RAM, and added a monitor as a standard option. The MCM/1000, aka MCM Power was a re-packaged /900, and was later re-packaged again as the MCM MicroPower. The new design was to be the basis of future models, including the considerably different "next generation" A*2. 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

MCM found that the Canadian business market was unprepared to risk venture capital on the computer market, which they did not understand. By the late 1970s MCM was facing a number of advanced home computer systems with the same sort of power as their own machines, and the funding needed to make competitive machines was not available. The company was shut down in 1982 or 83.when

Rights to the A*2 design were sold to Ampex. They worked on the design for about a year before also shutting down development.

External links

* [http://www.cs.yorku.ca/museum/ York University Computer Museum] – Includes a number of items from the MCM company