Masatoshi Shima

Professor Masatoshi Shima Dr.Eng.
嶋正利
at the Computer History Museum 2009 Fellow Awards event
Born	(1943-08-22) August 22, 1943 (age 80) Shizuoka, Shizuoka Prefecture, Japan
Citizenship	Japan
Education	B.S., Tohoku University (1967) Dr.Eng., Tsukuba University (1991)
Known for	Microprocessors: Intel 4004, 8080, Zilog Z80, Z8000 Peripheral chips: Intel 8259, 8255, 8253, 8257, 8251
Awards	Kyoto Prize (1997) Computer History Museum Fellow (2009)[1]
Scientific career
Fields	Electronic engineering Microprocessor
Institutions	Busicom (1967-1972) Intel (1972-1975) Zilog (1975-1980)[2] University of Aizu (2000)

Masatoshi Shima (嶋 正利, Shima Masatoshi, born August 22, 1943, Shizuoka) is a Japanese electronics engineer. He was one of the architects of the world's first microprocessor, the Intel 4004. In 1968, Shima worked for Busicom in Japan, and did the logic design for a specialized CPU to be translated into three-chip custom chips. In 1969, he worked with Intel's Ted Hoff and Stanley Mazor to reduce the three-chip Busicom proposal into a one-chip architecture. In 1970, that architecture was transformed into a silicon chip, the Intel 4004, by Federico Faggin, with Shima's assistance in logic design.^[3][4][5]

He later joined Intel in 1972. There, he worked with Faggin to develop the Intel 8080, released in 1974. Shima then developed several Intel peripheral chips, some used in the IBM PC, such as the 8259 interrupt controller, 8255 programmable peripheral interface chip, 8253 timer chip, 8257 direct memory access (DMA) chip and 8251 serial communication USART chip. He then joined Zilog, where he worked with Faggin to develop the Zilog Z80 (1976) and Z8000 (1979).^[2]