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DYSEAC

DYSEAC was the second Standards Electronic Automatic Computer.

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DYSEAC
DYSEAC van No. 1
ManufacturerNational Bureau of Standards for the U.S. Army Signal Corps
Generation1
ReleasedApril 1954 (1954-04)
CPU900 vacuum tubes and 24,500 crystal diodes
Memory512 words of 45 bits each (plus 1 parity bit) (mercury delay-line memory)
Weight20 short tons (18 t)
PredecessorSEAC
Cross-sectional diagram of a DYSEAC van source ↗

DYSEAC was the second Standards Electronic Automatic Computer. (See SEAC.)

DYSEAC was a first-generation computer built by the National Bureau of Standards for the U.S. Army Signal Corps. It was housed in a truck, making it one of the first movable computers (perhaps the first). It went into operation in April 1954.1

DYSEAC used 900 vacuum tubes and 24,500 crystal diodes. It had a memory of 512 words of 45 bits each (plus one parity bit), using mercury delay-line memory. Memory access time was 48–384 microseconds. The addition time was 48 microseconds, and the multiplication/division time was 2112 microseconds. These times are excluding the memory-access time, which added up to approximately 1500 microseconds to those times.

DYSEAC may have been the first computer to implement interrupts for I/O.1

DYSEAC weighed about 20 US tons (18 metric tons).2

See also

See also

References

References

  1. "9. Bureau of Standards Computers – DYSEAC". Digital Computer Newsletter. 6 (4): 8. October 1954.
  2. Weik, Martin H. (March 1961). "DYSEAC". ed-thelen.org. A Third Survey of Domestic Electronic Digital Computing Systems.
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