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Pier Giorgio Perotto

Abstract

Pier Giorgio Perotto (1930–2002) was the Olivetti engineer whose project was too small to be sold. When Olivetti gave up its computer division to General Electric in 1964, Perotto’s four-man team in Ivrea stayed behind because the machine they were building was classified, on paper, as a calculator. The Programma 101, shown in New York in October 1965, was a programmable computer that sat on a desk, ran from a wall socket, stored its programs on magnetic cards, and cost $3,200 at a time when a computer cost the price of a house and lived in its own room. Olivetti sold 44,000, NASA used them to plan Apollo 11, and Hewlett-Packard paid $900,000 in royalties when its 9100A copied the design. Perotto stayed at Olivetti until 1993 and spent the rest of his life arguing, correctly, that he had built the first personal computer.

P101 Team Perotto
The Programma 101 team in Ivrea, 1962–64: Perotto, Giovanni De Sandre, Gastone Garziera and Giancarlo Toppi. Image: Laboratorio-Museo Tecnologic@mente, public domain, via Wikimedia Commons.

Turin and Ivrea

Perotto was born in Turin on December 24, 1930, and took a degree in electrical engineering at the Politecnico di Torino in 1952, followed by one in aeronautical engineering. He worked at Fiat for two years and in 1957 joined Olivetti’s electronics research laboratory at Barbaricina near Pisa, directed by Mario Tchou. The company was Italy’s typewriter and calculator maker, run from Ivrea by Adriano Olivetti as an experiment in industrial humanism, and it had just decided to build computers: the ELEA 9003, delivered in 1959, was among the first transistorised commercial computers in the world (see Camillo and Adriano Olivetti). Perotto worked in the electronics division on the ELEA line.

Adriano Olivetti died on a train in February 1960, and the company that had been his lost its nerve. Banks and the Fiat-led group that rescued it in 1964 regarded the computer division as a drain, and sold it to General Electric that year. Perotto had by then moved back to Ivrea with a small team and a project of his own, and because that project was described as a calculator, it was not in the deal. (The Heinz Nixdorf MuseumsForum places the team at an Olivetti plant near Milan rather than in Ivrea.) Inside the company the machine was nicknamed the “Perottina”; a prototype ran in November 1964.

The Programma 101

The idea was a machine for a person rather than an institution: a computer that an engineer or an accountant could put on a desk, switch on, and program without a staff. Between 1962 and 1964 Perotto, Giovanni De Sandre and Gastone Garziera, joined by Giancarlo Toppi, designed it from discrete transistors and diodes, with a memory of 240 bytes on a magnetostrictive delay line, a wire in which data circulated as acoustic pulses, a keyboard of 36 keys, and a printer that put results on a paper roll. A program of up to 120 instructions was typed in, could branch on conditions, and could be saved to a plastic card with a magnetic stripe and reloaded by pushing the card into a slot, which made the machine reusable by someone who had never written the program. The programmer had fifteen instructions and ten registers, each holding a 22-digit number or up to 24 instructions; the electronics sat on about 900 small transistor modules, and the whole machine weighed 35.5 kg. Mario Bellini designed the case, and it looked like nothing else in the building.

The Programma 101 was presented in New York in mid-October 1965 (October 15 in Olivetti’s accounts, October 14 according to the HNF), at the time of the BEMA office-equipment show, where visitors could see it at the New York Coliseum from October 25 to 29. It sold in the United States from 1966 at $3,200 and in Europe from 1967; in West Germany it cost DM 16,428, against DM 21,000 for HP’s 9100A. About 44,000 were made, nine in ten of them sold in the United States, where the first customers were engineers, surveyors and universities, and where NASA bought about ten and used them for calculations on the Apollo 11 mission. The US Air Force used it in the same year for bombing missions over Vietnam. Production of the first model ended in 1971, after a more elaborate Programma 203 had joined it in 1967. When Hewlett-Packard introduced its 9100A desktop calculator in 1968, Olivetti’s patents on the magnetic-card program storage were found to cover it and HP reportedly paid about $900,000 in royalties, the sum that told the industry which machine had come first. HP’s own account of the 9100A was that it was the first personal computer; Perotto’s was that it had been the second, and the money agreed with him. The Italian story around the machine, and why Olivetti did not build on it at scale, is in Italy’s Computing Industry.

After the P101

Perotto rose to general director of projects and research at Ivrea and led the machines that followed, among them the P6040, built around an Intel 8080, and the P6060 (1975), a desktop computer with a built-in floppy-disk drive, a screen and BASIC, which was a personal computer by anyone’s definition and arrived two years before the Apple II. Olivetti under Carlo De Benedetti became Europe’s largest PC maker in the 1980s on the M24, but the personal computer as a category was named and sold from California, and the company’s own history of having built one first stayed in Italian. From 1979 he ran ELEA, a management consultancy linked to Olivetti. He received the Leonardo da Vinci Prize of Milan’s science museum in 1991, left Olivetti in 1993, became president of the consultancy FINSA in 1997, and wrote books on management and one, in 1995, on the Programma 101, whose subtitle called it the invention of the personal computer. He died in Genoa on January 23, 2002. Asteroid 12222 Perotto is named for him, and Garziera, the last of the team, spent his later years giving the demonstration Perotto had given in New York.

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