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The Man Who Invented The Pc

Fall 1994 | Volume 10 |  Issue 2

When I tell them I invented the personal computer, people look at me like I just stepped off a flying saucer,” says Jack Frassanito, an industrial designer in Houston, Texas. He did invent it, though. His name is on a patent, issued July 25, 1972, for a machine that is the direct lineal ancestor of the PC as we know it.

Forget Apple and IBM. For that matter, forget Silicon Valley. The first personal computer—a self-contained unit with its own processor, display, keyboard, internal memory, and mass storage of data—was born in San Antonio, Texas.

The story begins in July 1968, when two Texans, Phil Ray and Gus Roche, founded a firm called Computer Terminal Corporation (CTC). As the name implies, they did not start out making computers; instead they made terminals to use with other manufacturers’ computers. Their first product was an electronic replacement for mechanical teletypes.

In 1969 they decided to market a “smart” device that could mimic the terminal of any major computer vendor. Such an adaptable machine would have to have its own processor instead of simply passing along signals from a central unit. The company hired Frassanito to help develop the design. Since it would be used by office workers rather than engineers, CTC wanted to make it less intimidating by disguising the fact that it was a computer terminal.

“It was to have the footprint, size, and shape of an IBM Selectric typewriter,” recalls Vie Poor, then CTC’s technical director. The screen was only twelve lines high—the same size as the standard IBM punch card, since CTC also hoped to sell the new computer as a convenient electronic replacement for the mechanical card-punch machines then in use.

Poor laid out the terminal’s workings on printed circuit boards. Fitting everything into such a small space led to crowding and heat problems, and Poor thought about reducing the circuitry onto a microchip. Such chips had been used for several years to perform specific logic functions, but never before had all the circuits for a central processing unit been put on a single one. Intel and Texas Instruments (TI) agreed to try, but neither completed its chip before CTC unveiled the terminal in June 1970.

It was called the Datapoint 2200, and it had up to 8,000 bytes of internal storage, with another 300,000 on two cassette tapes. It was some 4,000 times slower than the 486-class PCs available today. The basic model cost about $5,000. The first 2200s were shipped in early 1971, and one of them went to a Pillsbury chicken-processing plant in El Dorado, Arkansas. Poor called a technician there to see how the machine was working out. Since normal telephone lines were not reliable enough for transmitting data, he asked what kind of connection the out-of-the-way plant was using to link its terminal to the mainframe, presumably at corporate headquarters in Minneapolis.

“None,” replied the technician. He had read through the terminal’s documentation and written a payroll program on the 2200 itself, using machine language. The only mainframe connection was the post office; data was periodically output onto cassettes and mailed to Minnesota. Other buyers were applying the Datapoint to accounting and process control; in fact, few of the machines were being used for the purpose they’d been designed for. Desktop computing had been born—brought into existence by resourceful users, not computer designers or marketers.

Meanwhile, TI and Intel belatedly came back with their chips, but CTC was no longer interested. Intel added the chip it had designed for CTC to its catalogue, naming it the 8008. A later upgrade, the 8080, formed the heart of the Altair and IMSAI computers of the mid-1970s; a further modification, the 8088, was used in the first IBM PC. It was, followed by the 80286, the 80386, the 80486, and the Pentium—the PC revolution’s chip dynasty. If you are using a PC, you are using a modernized Datapoint 2200.

The versatile Frassanito has since worked for NASA and designed the SaniFresh soap dispenser. Poor has retired; Roche died in 1975 and Ray in 1987. CTC became Datapoint Corporation in 1972 and pioneered office automation, inventing the local area network in 1977. Through the 1970s it continued to use in-house upgrades of the 2200’s processor boards instead of Intel’s chips. In the 1980s, however, Datapoint could not compete with the PC market and was nearly devoured by its own offspring. Today it mainly sells video teleconferencing systems.

As Frassanito observes, “Pioneers get arrows.”

We hope you enjoyed this essay.

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