The MUSASINO-1 was one of the earliest electronic digital

computer A computer is a machine that can be programmed to Execution (computing), carry out sequences of arithmetic or logical operations (computation) automatically. Modern digital electronic computers can perform generic sets of operations known as C ...

s built in

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

. Construction started at the Electrical Communication Laboratories of NTT at

Musashino, Tokyo is a city located in the western portion of Tokyo Metropolis, Japan. , the city had an estimated population of 147,492 in 77,779 households, and a population density of 13,000 persons per km². The total area of the city is . Based on the 2015 Ka ...

in 1952 and was completed in July 1957. The computer was used until July 1962. Saburo Muroga, a

University of Illinois The University of Illinois Urbana-Champaign (U of I, Illinois, University of Illinois, or UIUC) is a public land-grant research university in Illinois in the twin cities of Champaign and Urbana. It is the flagship institution of the University ...

visiting scholar and member of the

ILLIAC I The ILLIAC I (Illinois Automatic Computer), a pioneering computer in the ILLIAC series of computers built in 1952 by the University of Illinois, was the first computer built and owned entirely by a United States educational institution. Computer ...

team, returned to Japan and oversaw the construction of MUSASINO-1. Using 519

vacuum tube A vacuum tube, electron tube, valve (British usage), or tube (North America), is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. The type kn ...

s and 5,400

parametron Parametron is a logic circuit element invented by Eiichi Goto in 1954.Information Processing Society of Japan Parametron/ref> The parametron is essentially a resonant circuit with a nonlinear reactive element which oscillates at half the driving f ...

s, the MUSASINO-1 possessed a

magnetic core memory Magnetic-core memory was the predominant form of random-access computer memory for 20 years between about 1955 and 1975. Such memory is often just called core memory, or, informally, core. Core memory uses toroids (rings) of a hard magnetic ...

, initially of 32 (later expanded to 256)

words A word is a basic element of language that carries an objective or practical meaning, can be used on its own, and is uninterruptible. Despite the fact that language speakers often have an intuitive grasp of what a word is, there is no consen ...

. A word was composed of 40

bit The bit is the most basic unit of information in computing and digital communications. The name is a portmanteau of binary digit. The bit represents a logical state with one of two possible values. These values are most commonly represente ...

s, and two instructions could be stored in a single word. Addition time was clocked at 1,350

microsecond A microsecond is a unit of time in the International System of Units (SI) equal to one millionth (0.000001 or 10−6 or ) of a second. Its symbol is μs, sometimes simplified to us when Unicode is not available. A microsecond is equal to 1000 n ...

s, multiplication at 6,800 microseconds, and division time at 26.1

millisecond A millisecond (from '' milli-'' and second; symbol: ms) is a unit of time in the International System of Units (SI) equal to one thousandth (0.001 or 10−3 or 1/1000) of a second and to 1000 microseconds. A unit of 10 milliseconds may be called ...

s. The MUSASINO-1's

instruction set In computer science, an instruction set architecture (ISA), also called computer architecture, is an abstract model of a computer. A device that executes instructions described by that ISA, such as a central processing unit (CPU), is called an ' ...

was a

superset In mathematics, set ''A'' is a subset of a set ''B'' if all elements of ''A'' are also elements of ''B''; ''B'' is then a superset of ''A''. It is possible for ''A'' and ''B'' to be equal; if they are unequal, then ''A'' is a proper subset of ...

of the ILLIAC I's instructions, so it could generally use the latter's

software Software is a set of computer programs and associated documentation and data. This is in contrast to hardware, from which the system is built and which actually performs the work. At the lowest programming level, executable code consists ...

. However, many of the programs for the ILLIAC used some of the unused bits in the instructions to store data, and these would be interpreted as a different instructions by the MUSASINO-1 control circuitry.

References

*Raúl Rojas and Ulf Hashagen, ed. ''The First Computers: History and Architectures''. 2000, MIT Press, . *''In memory of Saburo Muroga, CS @ Illinois Alumni Magazine, Summer 2011''

See also

References

External links