SEAC (computer)

SEAC (computer)

SEAC ("Standards Electronic/Eastern Automatic Computer") was a first-generation electronic computer, built in 1950 by the U.S. National Bureau of Standards (NBS) and was initially called the "National Bureau of Standards Interim Computer", because it was a small-scale computer designed to be built quickly and put into operation while the NBS waited for more powerful computers to be completed. SEAC was demonstrated in April 1950, and in May 1950 it went into full production, making it the first fully functional stored-program electronic computer in the US.__NOTOC__

Description

Based on EDVAC, SEAC used only 747 vacuum tubes (a small number for the time) eventually expanded to 1500 tubes but 10,500 germanium diodes also expanded to 16,000. It also used no transistors, since all of the logic was done with diodes, making it the first computer to do all of its logic with solid-state devices. The tubes were used only for amplification and/or inversion. The machine used 64 acoustic delay lines to store 512 words of memory, with each word being 45 bits in size. The clock rate was kept low (1 MHz).

The computer's instruction set consisted of only eleven types of instructions: fixed-point addition, subtraction, multiplication, and division; comparison, and input & output eventually expanded to 16. The addition time was 864 microseconds and the multiplication time was 2980 microseconds (i.e. close to 3 milliseconds).

Applications

On some occasions SEAC was used by a remote teletype. This makes it one of the first computers to be used remotely. With many modifications, it was used until 1964. Some of the problems run on it dealt with:

* meteorology
* linear programming
* optical lenses
* a program for Los Alamos National Laboratory
* tables for Loran navigation
* statistical sampling plans
* wave function of the helium atom
* designing a proton synchrotron

ee also

* SWAC (Standards Western Automatic Computer)

References

* Williams, Michael R. (1997). "A History of Computing Technology". IEEE Computer Society.
* Metropolis, N; Howlett, J.; Rota, Gian-Carlo (editors) (1980). "A History of Computing in the Twentieth Century". Academic Press. (The chapter "Memories of the Bureau of Standards' SEAC", by Ralph J. Slutz.)Astin,A.V. (1955), "Computer Development (SEAC and DYSEAC) at the National Bureau of Standards, Washington D.C., National Bureau of Standards Circular 551, U.S. Government Printing Office, January 25, 1955

External links

* [http://museum.nist.gov/panels/seac/SEACOVER.HTM SEAC and the Start of Image Processing at the National Bureau of Standards] – At the NIST virtual museum


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • SEAC — (сокр. от англ. Standards Electronic/Eastern Automatic Computer, Стандартизированный электронный восточный автоматический компьютер)  электронный компьютер первого поколения, построенный в 1950 году Национальным бюро стандартов США …   Википедия

  • SEAC — /sēˈak/ abbrev 1. Formerly, School Examination and Assessment Council 2. South East Asia Command (in World War II) 3. Spongiform Encephalopathy Advisory Committee * * * SEAC (no periods), Standard Eastern Automatic Computer (a high speed,… …   Useful english dictionary

  • SEAC — The term SEAC can stand for: * South East Asia Command, a World War II Allied military command * Standards Electronic/Eastern Automatic Computer, a first generation electronic computer built in 1950 * Student Environmental Action Coalition, a… …   Wikipedia

  • SEAC — Standard s Eastern Automatic Computer erster Computer mit Benutzung von Transistoren, entwickelt am National Bureau of Standards …   Acronyms

  • SEAC — Standard s Eastern Automatic Computer erster Computer mit Benutzung von Transistoren, entwickelt am National Bureau of Standards …   Acronyms von A bis Z

  • SEAC — abbr. Standards Eastern Automatic Computer comp. abbr. Name of first computer to use transistors, built by National Bureau of Standards Eastern Automatic Calculator …   United dictionary of abbreviations and acronyms

  • SWAC (computer) — The SWAC (Standards Western Automatic Computer) was an early electronic digital computer built in 1950 by the U.S. National Bureau of Standards (NBS) in Los Angeles, California. It was designed by Harry Huskey. Like the SEAC, built about the same …   Wikipedia

  • Electronic Numerical Integrator and Computer — Electronic Numerical Integrator Analyser and Computer L ENIAC L ENIAC, acronyme de l anglais Electronic Numerical Integrator Analyser and Computer, est le premier ordinateur entièrement électronique construit pour être Turing complet. Il peut… …   Wikipédia en Français

  • Electronic Numerical Integrator Analyser and Computer — 39° 57′ 08″ N 75° 11′ 26″ W / 39.9522, 75.1905 …   Wikipédia en Français

  • Data buffer — In computer science, a buffer is a region of a physical memory storage used to temporarily hold data while it is being moved from one place to another. Typically, the data is stored in a buffer as it is retrieved from an input device (such as a… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”