Edvac

Information about Edvac

EDVAC (Electronic Discrete Variable Automatic Computer) was one of the earliest electronic computers. Unlike its predecessor the ENIAC, it was binary rather than decimal, and was a stored program machine.

Project origin and plan

ENIAC inventors John Mauchly and J. Presper Eckert proposed the EDVAC's construction in August 1944, and design work for the EDVAC commenced before the ENIAC was fully operational. The design would implement a number of important architectural and logical improvements conceived during the ENIAC's construction and would incorporate a high speed serial access memory^[1]. Like the ENIAC, the EDVAC was built for the U.S. Army's Ballistics Research Laboratory at the Aberdeen Proving Ground by the University of Pennsylvania's Moore School of Electrical Engineering. Eckert and Mauchly and the other ENIAC designers were joined by John von Neumann in a consulting role; von Neumann summarized and elaborated upon logical design developments in his 1945 First Draft of a Report on the EDVAC.^[2]

A contract to build the new computer was signed in April 1946 with an initial budget of US$100,000. The contract named the device the Electronic Discrete Variable Automatic Calculator. The final cost of EDVAC, however, was similar to the ENIAC's, at just under $500,000, five times the initial estimate.

Technical description

The EDVAC was a binary serial computer with automatic addition, subtraction, multiplication, programmed division and automatic checking with an ultrasonic serial memory^[1] capacity of 1,000 44-bit words (later set to 1,024 words, thus giving a memory, in modern terms, of 5.5 kilobytes).

Physically, the computer comprised the following components:

a magnetic tape reader-recorder (Wilkes 1956:36^[1] describes this as a wire recorder.)
a control unit with an oscilloscope
a dispatcher unit to receive instructions from the control and memory and direct them to other units
a computational unit to perform arithmetic operations on a pair of numbers at a time and send the result to memory after checking on a duplicate unit
a timer
a dual memory unit consisting of two sets of 64 mercury acoustic delay lines of eight words capacity on each line
three temporary tanks each holding a single word^[1]

EDVAC's addition time was 864 microseconds and its multiplication time was 2900 microseconds (2.9 milliseconds).

The computer had almost 6,000 vacuum tubes and 12,000 diodes, and consumed 56 kW of power. It covered 490 ft² (45.5 m²) of floor space and weighed 17,300 lb (7,850 kg). The full complement of operating personnel was thirty people for each eight-hour shift.

Installation and operation

EDVAC was delivered to the Ballistics Research Laboratory in August 1949. After a number of problems had been discovered and solved, the computer began operation in 1951 although only on a limited basis. Its completion was delayed because of a dispute over patent rights between Eckert and Mauchly and the University of Pennsylvania, resulting in Eckert and Mauchly's resignation and departure to form the Eckert-Mauchly Computer Corporation and taking most of the senior engineers with them.

By 1960 EDVAC was running over 20 hours a day with error-free run time averaging eight hours. EDVAC received a number of upgrades including punch-card I/O in 1953, extra memory in slower magnetic drum form in 1954, and a floating point arithmetic unit in 1958.

EDVAC ran until 1961 when it was replaced by BRLESC. During its lifetime it proved to be reliable for its time and productive.

References

1. ^ Wilkes, M. V. (1956). Automatic Digital Computers. New York: John Wiley & Sons, 305 pages. QA76.W5 1956 .
2. ^ "First Draft of a Report on the EDVAC" (PDF format) by John von Neumann, Contract No.W-670-ORD-4926, between the United States Army Ordnance Department and the University of Pennsylvania. Moore School of Electrical Engineering, University of Pennsylvania, June 30, 1945. The report is also available in Stern, Nancy (1981). From ENIAC to UNIVAC: An Appraisal of the Eckert-Mauchly Computers. Digital Press. .
3. ^ Wilkes
4. ^ Wilkes
5. ^ Wilkes

Electronics is the study of the flow of charge through various materials and devices such as, semiconductors, resistors, inductors, capacitors, nano-structures, and vacuum tubes. All applications of electronics involve the transmission of power and possibly information.
..... Click the link for more information.

computer is a machine which manipulates data according to a list of instructions.

Computers take numerous physical forms. The first devices that resemble modern computers date to the mid-20th century (around 1940 - 1941), although the computer concept and various machines
..... Click the link for more information.

ENIAC, short for Electronic Numerical Integrator And Computer,^[1] was the first large-scale, electronic, digital computer capable of being reprogrammed to solve a full range of computing problems,^[2]
..... Click the link for more information.

binary numeral system, or base-2 number system, is a numeral system that represents numeric values using two symbols, usually 0 and 1. More specifically, the usual base-2 system is a positional notation with a radix of 2.
..... Click the link for more information.

decimal (base ten or occasionally denary) numeral system has ten as its base. It is the most widely used numeral system, perhaps because humans have four fingers and a thumb on each hand, giving a total of ten digits over both hands.
..... Click the link for more information.

von Neumann architecture is a computer design model that uses a processing unit and a single separate storage structure to hold both instructions and data. It is named after mathematician and early computer scientist John von Neumann.
..... Click the link for more information.

John William Mauchly (August 30 1907 – January 8 1980) was an American physicist who, along with J. Presper Eckert, designed ENIAC, the first general purpose electronic digital computer, as well as EDVAC, BINAC and UNIVAC I, the first commercial computer made in the United
..... Click the link for more information.

John Adam Presper "Pres" Eckert Jr. (born April 9, 1919 in Philadelphia, Pennsylvania; died June 3, 1995 in Bryn Mawr, Pennsylvania) was an American computer pioneer. With John Mauchly he invented the first general-purpose electronic digital computer (ENIAC), presented the first
..... Click the link for more information.

Delay line memory was a form of computer memory used on some of the earliest digital computers. Like many modern forms of electronic computer memory, delay line memory was a refreshable memory, but as opposed to modern random access memory, delay line memory was serial
..... Click the link for more information.

The United States Army is the largest and oldest branch of the armed forces of the United States. Like all armies, it has the primary responsibility for land-based military operations.
..... Click the link for more information.

The United States Army Ballistic Research Laboratory (BRL) at Aberdeen Proving Ground, Maryland was the center for the army's research efforts in interior, exterior, and terminal ballistics and vulnerability/lethality analysis.
..... Click the link for more information.

Aberdeen Proving Ground (APG) is a United States Army facility located near Aberdeen, Maryland (in Harford County).

The Army's oldest active proving ground, it was established on October 20, 1917, six months after the United States entered World War I.
..... Click the link for more information.

University of Pennsylvania (also known as Penn^[3]^[4]) is a private, coeducational research university located in Philadelphia, Pennsylvania. According to the university, it is America's first university^[5] and is the fourth-oldest
..... Click the link for more information.

The Moore School of Electrical Engineering at the University of Pennsylvania came into existence as a result of an endowment from Alfred Fitler Moore on June 4, 1923. It was granted to the Penn's School of Electrical Engineering, located in the Towne Building.
..... Click the link for more information.

John von Neumann

John von Neumann in the 1940s
Born November 28 1903
Budapest, Austria-Hungary
..... Click the link for more information.

The First Draft of a Report on the EDVAC (commonly shortened to First Draft) was an incomplete 101-page document written by John von Neumann and distributed on June 30, 1945 by Herman Goldstine, security officer on the classified ENIAC project.
..... Click the link for more information.

United States dollar
dólar estadounidense (Spanish)
dólar amerikanu (Tetum)
dólar americano
..... Click the link for more information.

A Serial computer is typified by internally operating on one bit or digit for each clock cycle. Machines with serial main storage devices such as acoustic or magnetostrictive delay lines and rotating magnetic devices were usually serial computers.
..... Click the link for more information.

word" is a term for the natural unit of data used by a particular computer design. A word is simply a fixed-sized group of bits that are handled together by the machine. The number of bits in a word (the word size or word length
..... Click the link for more information.

kilobyte (derived from the SI prefix kilo-, meaning 1,000) is a unit of information or computer storage equal to either 1,000 bytes or 1,024 bytes (2¹⁰), depending on context.
..... Click the link for more information.

Magnetic tape is a medium for magnetic recording generally consisting of a thin magnetizable coating on a long and narrow strip of plastic. Nearly all recording tape is of this type, whether used for recording audio or video or for computer data storage.
..... Click the link for more information.

Wire recording is a type of analogue audio storage in which the recording is made onto thin steel or stainless steel wire.

History

The first wire recorder was the Valdemar Poulsen Telegraphone of the late 1890s, and wire recorders for law/office dictation and telephone
..... Click the link for more information.

oscilloscope (sometimes abbreviated CRO, for cathode-ray oscilloscope, or commonly just scope or O-scope) is a type of electronic test equipment that allows signal voltages to be viewed, usually as a two-dimensional graph of one or more electrical potential
..... Click the link for more information.

2, 1
(mildly basic oxide)
Electronegativity 2.00 (scale Pauling)
Ionization energies 1st: 1007.1 kJ/mol
2nd: 1810 kJ/mol
3rd: 3300 kJ/mol
Atomic radius 150 pm
Atomic radius (calc.
..... Click the link for more information.

The term delay line has multiple meanings:

In electronics and derivative fields such as telecommunications, a delay line is a device where the input signal reaches the output of the device after a known period of time has elapsed.

..... Click the link for more information.

To help compare orders of magnitude of different times this page lists times between 10⁻⁶ seconds and 10⁻⁵ seconds (1 microsecond to 10 microseconds). A microsecond is one millionth of a second.
..... Click the link for more information.

vacuum tube, electron tube (inside North America), thermionic valve, or just valve (elsewhere); is a device used to amplify, switch, otherwise modify, or create an electrical signal by controlling the movement of electrons in a low-pressure space, often not
..... Click the link for more information.

diode is a component that restricts the directional flow of charge carriers. Essentially, a diode allows an electric current to flow in one direction, but blocks it in the opposite direction. Thus, the diode can be thought of as an electronic version of a check valve.
..... Click the link for more information.

This article is copied from an article on Wikipedia.org - the free encyclopedia created and edited by online user community. The text was not checked or edited by anyone on our staff. Although the vast majority of the wikipedia encyclopedia articles provide accurate and timely information please do not assume the accuracy of any particular article. This article is distributed under the terms of GNU Free Documentation License.

Herod_Archelaus