From WikiChip

Busicom is a now-defunct Japanese high-end desktop calculator maker best known for their partnership with Intel that resulted in the world's first commercial microprocessor. Nippon Calculating Machine Corp


Japan has had a long tradition of mathematics and calculator building dating back to as early as 1902. March that year, Ryōichi Yazu applied for a patent on his mechanical calculator, Japan's first mechanical calculator. In 1906, the Japanese Ministry of Communications and Transportation built an electronic calculator.

In 1945, a company by the name Nippon Calculating Machine Corp was founded to build calculators. The company was later renamed Business Computer Corporation - Busicom in 1967. At the same time the company was also developing a brand of electronic calculators called Busicom. During the spring of 1969 Intel had a MOS team that was working on silicon-gate memory. In early 1970, Busicom contacted a Silicon Valley company called Intel to help develop a microprocessor for its high-end calculator, the 141-PF calculator. At the time Intel was only a memory company, working with Busicom on their chips was orthogonal to Intel's primary business.

At the time, Busicom was looking to develop a set of 12 specialized chips, each consisting of 3,000 to 5,000 transistors. Busicom planned on sending a team of engineers to Intel to design the chips on-site and have Intel manufacture its calculator chip sets for roughly $100,000. Busicom expected Intel to manufacture at least 60,000 of them and buy them for $50 each. The Busicom engineering group arrived in California at the end of June. Soon after arriving, the concept of 12 chips proved to be very complex - 1 chip was to be used exclusively to store values, another was to interface with the keyboard, another to interface with the screen. Marcian Hoff, an employee at Intel proposed an alternative scheme where a single general-purpose chip would do the bulk of the work. The idea was quickly turned down by the Busicom who failed to envision the idea.

Hoff's design was much more elegant, requiring just four chips, memory, a shift register, and a general purpose chip. The development was lead by a new employee, Federico Faggin, who came from Fairchild Semiconductor.