Standards Eastern Automatic Computer / Standards Electronic Automatic Computer | 1950

SEAC

 


SEAC (Standards Eastern Automatic Computer or Standards Electronic Automatic Computer) was a first-generation electronic computer developed in 1950 by the National Bureau of Standards (NBS) in the United States. Initially called the NBS Temporary Computer, it was designed to be a small computer that could be quickly built and operated while NBS awaited the completion of a more powerful computer (DYSEAC). The SEAC development team was organized by Samuel N. Alexander. SEAC was demonstrated in April 1950 and dedicated in June, claiming to be the first fully operational stored-program electronic computer in the United States.

SEAC was based on EDVAC and initially used 747 vacuum tubes, later expanding to 1,500. It utilized 10,500 germanium diodes to perform all logical functions, which later increased to 16,000. SEAC was the first computer to perform most of its logic using solid-state devices. Vacuum tubes were used to amplify, invert, and store information in dynamic flip-flops. The machine employed 64 acoustic delay lines to store 512 words, with each word size being 45 bits. The clock speed was kept low at 1 MHz.

The instruction set of the computer consisted of 11 types of commands, including fixed-point addition, subtraction, multiplication, division, comparison, input, and output, later expanded to 16.

The addition time was 864 microseconds, and the multiplication time was 2,980 microseconds (close to 3 milliseconds).

The weight of the central machine was 3,000 pounds (1.5 tons; 1.4 metric tons).


이 블로그의 인기 게시물

콜러서스 컴퓨터 [Colossus computer | December 1943]

NTDS [Naval Tactical Data System | 1961]

에니악 [ENIAC | December 10, 1945]