cpm

CPM

(1) (Critical Path Method) A project management planning and control technique. The critical path is the series of tasks that have no built-in slack time. Any one of those tasks that takes longer to complete lengthens the total project time.

(2) (Cost Per Mille/Milli) Cost per thousand. See RPM.

(3) (Copies Per Minute) The rated speed of a printer or copy machine.

(4) (CP/M) (Control Program for Microprocessors) A single user operating system for the 8080 and Z80 microprocessors. Created by Gary Kildall of Digital Research, CP/M had its heyday in the early 1980s, and although unsophisticated, was a major contributor to the personal computer revolution. However, CP/M computer vendors never standardized a floppy disk or screen format, requiring software publishers to create and stock multiple CP/M versions. After entering this uncontrolled market in 1981, IBM readily set the personal computer standards with its PC, and some of those standards remain to this day (see IBM PC).

CP/M Might Have Become DOS
Although IBM asked Kildall to provide the operating system for its new PC, he did not agree to all of IBM's demands. IBM went to Microsoft, which purchased QDOS from Seattle Computer Products and turned it into PC-DOS and MS-DOS. The rest is history. The irony is that Microsoft's DOS was modeled after CP/M. Digital Research was later acquired by Novell and then Caldera, which later merged with The SCO Group.

The Otrona Attache

Introduced in 1982, the Attache was the smallest CP/M portable computer on the market. Weighing 17 pounds and priced at $5,000, the Attache became the elite computer in the CP/M heyday. (Image courtesy of Robin Bartlett.)

CP/M News Clips in Its Heyday

CP/M was the only OS that ran on microcomputers from different vendors. With a Z80 card, it even ran on the Apple II. A major contributor to the personal computer revolution, CP/M motivated IBM to create the PC; the most successful platform in history.

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cpm

(physics)

cycle per minute

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CPM

(systems engineering)

critical path method

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cpm

Abbr. for “cycles per minute.”

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critical path method, CPM

A system of project planning, scheduling, and control which combines all relevant information into a single master plan, permitting the establishment of the optimum sequence and duration of operations; the interrelation of all the efforts required to complete a construction project are shown; an indication is given of the efforts which are critical to timely completion of the project.

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CPM - Control Program for Microcomputers