Part II (colossus, eniac, edvac)
What was needed was a machine whose computing, control and memory elements were completely electrical. In this case, the speed of operation would be limited not by the speed of mechanical moving parts but by the much greater speed of moving electrons.
World War II gave impetus1 and funding to computer research. The military needed faster machines for ballistic calculations and for breaking the German secret codes.
One of the earliest electronic digital computers was called the Colossus. The machine was developed by a team led by the British engineer Tommy Flowers in 1943. Its existence was kept so secret that it was not revealed until decades after it was built. British cryptographers used this machine to crack ciphers and codes produced by the German electromechanical devices called the Enigma and the Geheimschreiber (“Secret Writer”). The machine used approximately 1800 vacuum tubes for computations. Larger and more sophisticated versions were built over the next two years.
T
he
first general-purpose all-electroniccomputer
was ENIAC
(an
acronym for Electronic
Numerical
Integrator
and
Computer).
(See Figure 2)
Designed
by two American engineers, John Mauchly and Presper Eckert, ENIAC was
put into operation at the University of Pennsylvania in 1946.
Figure 2
ENIAC
First introduced in 1946, ENIAC remained in service until 1955. A portion of the machine is now on exhibit at the Smithsonian Institution in Washington, D.C.
The 30-ton machine was 5.5 meters high and 24 meters long. It contained 18,000 vacuum tubes linked by 800 kilometers of wiring, 70,000 resistors, 10,000 capacitors, 6,000 switches and 1,500 relays. Approximately 2,000 of the computer’s vacuum tubes were replaced each month by a team of six technicians. It was the most complex electronic system developed up to that time. ENIAC was 500 times as fast as the best electromechanical computer. A problem that took one minute to solve on ENIAC required eight to ten hours on an electromechanical machine. It performed about 5,000 additions per second. Many of ENIAC’s first tasks were for military purposes, such as calculating ballistic tables and designing atomic weapons.
As ENIAC was not a stored program machine, it had to be reprogrammed for each task, a process that could take several days. The next computers were built so that programs could be stored in internal memory and could be easily changed to adapt the computer to different tasks.
EDVAC (an acronym for Electronic Discrete Variable Automatic Computer) was constructed at about the same time as ENIAC. But EDVAC was the more advanced of the two machines. Two innovations that first appeared in EDVAC have been used in every computer since. First, EDVAC used binary notation to represent numbers inside the machine. Binary notation is a system for writing numbers that uses only two digits (0 and 1), instead of the ten digits (0-9) used in the conventional decimal notation. Binary notation is now recognized as the simplest way of representing numbers in an electronic machine. Second, EDVAC's program was stored in the machine's memory, just like the data. Previous computers had stored the program externally on punched cards or punched tapes. A stored-program computer is usually called a von Neumann machine in honor of the originator of the stored-program concept.
Notes: 1to give impetus to – дать стимул к.
EXERCISES
Ex. 17. Search the text for the English equivalents to the following words and phrases:
двадцатитрёхзначные числа;
без вмешательства человека;
следует сказать, что;
не доверял (сомневался);
хранение программы в компьютере;
не был знаком c;
предвидел;
приводился в действие электричеством;
едва был собран, как устарел;
финансирование исследований в области вычислительной техники;
быстродействующие машины для баллистических расчётов;
шифровальщики;
чтобы взламывать шифры и коды;
создан примерно в то же самое время.
Ex. 18. Answer the following alternative questions to the first part of the text. Begin with: I'm sure that… or I'm not sure but I think that… . Add something to develop the situation.
Did 100 or 200 years pass before a machine similar to Babbage's Analytical Engine was actually built? ___.
Was this machine called Howard Mark I or Harvard Mark I? ___.
Did Howard Aiken or a group of IBM engineers design the Mark I computer? ___.
Could this calculating machine perform two or four arithmetical operations? ___.
Was it a small or huge machine? ___.
Did the Mark I weigh more or less than 30 tons? ___.
Were the programs stored inside or outside the computer? ___.
Were paper tapes or compact disks used for inputting data? ___.
Was the Mark I used for commercial or military purposes? ___.
Was the Mark I powered by electricity or steam? ___.
Were the electromechanical computers high-speed or low-speed machines? ___.
Did Aiken build three or four versions of the Mark I? ___.
Ex. 19. Complete the sentences. Try to do it without consulting the text.
Electromechanical computers were not fast enough as their speed was limited by ___.
The speed of electronic machines is restricted by ___.
One of the earliest electronic digital computers was called ___.
This machine was developed by ___.
British cryptographers used the computer to ___.
ENIAC was the first ___.
This machine was designed by ___ and put into operation at ___ in ___.
The ___ of ENIAC was 30 tons, its ___ was 5.5 meters, its ___ was 24 meters.
ENIAC contained 18,000 ___ linked by ___.
About 2,000 of the computer’s vacuum tubes were replaced each month by ___.
This electronic machine was 500 times as fast as ___.
ENIAC was not a stored-program machine, that's why it ___.
EDVAC was developed ___.
If compared to ENIAC, EDVAC was ___.
Two innovations first appeared in EDVAC such as ___.
A stored-program computer is usually called ___.
Ex. 20. Memorize the following terms.
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Ex. 21. Read and translate TEXT B
FIVE GENERATIONS OF COMPUTERS
Since the development of the Harvard Mark I, the digital computing machines have progressed at a rapid pace. Computers are often divided into five generations according to a series of advances in hardware, mainly in logic circuitry. Each generation comprises a group of machines that share a common technology.
The First Generation (the 1940s – much of the 1950s)
ENIAC, along with other electronic computers built in the 1940s, marks the beginning of the so-called first-generation computers. These computers cost millions of dollars and filled entire rooms. They used thousands of vacuum tubes for calculation, control, and sometimes for memory as well. Vacuum tubes were bulky, unreliable, energy consuming devices generating large amounts of heat. The vacuum tubes of one machine consumed enough electricity to power a small town. As long as computers were tied down to vacuum tube technology, they could only be huge, heavy and expensive. Though their operations were very fast in comparison with manual calculations, they were slow by today's standards.
The Second Generation (the late 1950s – the early 1960s)
The invention of the transistor in 1947 resulted in a revolution in computer development. Germanium (later silicon) transistors were smaller, more reliable and efficient than the vacuum tubes that had been used in electronics up to that time. These semi-conductor devices generated and controlled the electric signals that operated the computer. By the late 1950s and early 1960s, vacuum tubes were no longer used in computers.
Transistors led to the creation of smaller, more powerful and faster computers known as minicomputers. They were operated by specialized technicians, who were often dressed in white lab coats and usually referred to as "computer priesthood1". The machines were expensive and difficult to use. Few people came in direct contact with them, not even their programmers. The typical interaction was as follows: a programmer coded instructions and data on preformatted paper, a keypunch operator transferred the data onto punch cards, a computer operator fed the cards into a card reader, and, finally, the computer executed the instructions or stored the cards' information for later processing.
The so-called second-generation computers, which used large numbers of transistors, were able to reduce computational time from milliseconds to microseconds or millionths of seconds. At that time, there were two types of computers. There were room-sized mainframes, costing hundreds of thousands of dollars that were built one at a time by companies such as International Business Machines Corporation and Control Data Corporation. There also were smaller (refrigerator-sized), cheaper (about 100,000 dollars), mass-produced minicomputers built by such companies as Digital Equipment Corp. and Hewlett-Packard Company for scientific research laboratories, large businesses and higher educational institutions.
Most people, however, had no direct contact with either type of computer, and the machines were popularly viewed as giant brains that threatened to eliminate jobs as a result of automation. The idea that anyone would have his or her own desktop computer was generally considered as far-fetched2.
The Third Generation (much of the 1960s – the 1970s)
The step forward in computer miniaturization came in 1958, when Jack Kilby, an American engineer, designed the first integrated circuit (IC). His prototype consisted of a germanium wafer that included hundreds of tiny transistors, diodes, resistors, and capacitors – the main components of electronic circuitry. The microchip itself was small enough to fit on the end of your finger (See Figure 1).
T
he
invention of the IC marks the beginning of the third generation of
computers. With integrated circuits, computers could be made smaller,
less expensive and more reliable. They could perform many data
processing operations in nanoseconds, which are billionths of
seconds.
Figure 1
The Integrated Circuit
The next jump in the development of computer technology came with the introduction of large-scale ICs. Using less-expensive silicon chips, engineers managed to place more and more electronic components on each chip. Whereas the older ICs contained hundred of transistors, the new ones contained thousands or tens of thousands (modern microprocessors can contain more than 40 million transistors).
It was the large-scale ICs that made possible to produce the microprocessor and the microcomputer. The price of computers then fell; more and more small businesses and individuals could afford to buy them. Microcomputers – systems no larger than portable television sets yet with large computing power – began to be called the personal computers (PCs). All these recent developments have resulted in a microprocessor revolution, which began in the middle 1970s and for which there is no end in sight.
The Fourth Generation (1980s and beyond)
By the beginning of the 1980s, integrated circuitry had advanced to very large-scale integration (VLSI). This technology greatly increased the circuit density of microprocessor, memory and support circuitry – i.e. those that serve to interface microprocessors with input-output devices. By the 1990s, some VLSI circuits had contained more than 3 million transistors on a silicon chip less than 2 square cm in area.
The digital computers using VLSI technologies are frequently referred to as fourth-generation systems. These computers are hundred times smaller than those of the first generation and a single chip is far more powerful than the whole ENIAC. They are characterized by low cost, ease of use and large capabilities.
This fourth generation is the first in which a lot of computers are widely used in business, science, industry, medicine, education, or for home use. In addition to the common applications in digital watches, pocket calculators and personal computers, there are microprocessors in practically every machine at home or business – from microwave ovens and cellular telephones to spacecrafts and Global Positioning System3 (GPS) devices.
The Fifth Generation
The computer revolution is very dynamic. We are on the threshold4 of the fifth generation of computers. The term was devised by the Japanese to describe the powerful, intelligent computers they wanted to build by the mid-1990s. Since then it has become an umbrella term5, encompassing many research fields in the computer industry. Today researchers in the USA, Western Europe, Japan work on the problems of artificial intelligence, the application of natural languages for inputting data, ultra-large-scale integration (ULSI) technologies, etc.
Notes:1priesthood– высшая каста,сленг спецы, асы, гуру;
2far-fetched– "притянутый за уши", нереальный;
3GlobalPositioningSystem– глобальная система навигации и определения положения;
4threshold– порог, преддверие, канун;
5umbrellaterm– всеохватывающий термин (номинация).
EXERCISES
Ex. 22. Search the text for the English equivalents to the following phrases:
ряд усовершенствований в аппаратном обеспечении компьютера;
так называемый;
знаменует начало;
вырабатывающий большое количество тепла;
потребляла столько электричества, что хватило бы на энергоснабжение небольшого города;
по сравнению с;
вырабатывать электрические сигналы и управлять ими;
электронные лампы больше не использовались в компьютерах;
оператор, отвечающий за нанесение данных на перфокарты или перфоленту;
вводить перфокарты в устройство для считывания;
сохранять информацию для дальнейшей обработки;
миникомпьютеры массового (серийного) производства;
шаг вперёд;
поместиться на кончике пальца;
одна миллиардная доля секунды;
следующий скачок в усовершенствовании вычислительной техники;
именно большие интегральные схемы позволили создать;
революция, которой не видно конца;
невысокая стоимость, простота в использовании, большие возможности;
термин был придуман;
использование естественных языков для ввода данных.
Ex. 23. Before answering the questions, fill in the gaps with the required auxiliary verbs. Consult the box if necessary. (TIP: Two questions don't require any auxiliary verbs.)
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Ex. 24. Choose the required variant to complete each sentence.
Computers are divided into generations according to a number of improvements in ___.
A. operating systems C. input devices
B. logic circuitry D. application software
___ marks the beginning of the so-called first-generation computers.
A. The Analytical Engine C. ENIAC
B. The Difference Engine D. The Harvard Mark II
As long as computers were tied down to vacuum tube technology, they could only be ___.
A. large, heavy, costly C. enormous, lightweight, expensive
B. huge, heavy, cheap D. small, inexpensive, powerful
Germanium transistors ___ the electrical signals that operated the computer.
A. produced and eliminated C. generated and controlled
B. consumed and heated D. devised and developed
During the 1970s, computers were big machines requiring thousands of ___.
A. electromechanical relays C. separate transistors
B. vacuum tubes D. integrated circuits
Mass-produced minicomputers built by such companies as Digital Equipment Corp. and Hewlett-Packard Company were used in ___.
A. higher schools C. scientific research institutes
B. small businesses D. secondary schools and at homes
The third-generation computers could perform many data processing operations in ___.
A. milliseconds C. nanoseconds
B. microseconds D. picoseconds
In the 1970s, more and more people could afford to buy computers because ___.
A. the IC was invented C. the computers became faster and reliable
B. the price of computers fell D. all people became computer-literate
In the beginning of the 1980s, ___ was introduced.
A. IC C. VLSI
B. LSIC D. IBM
The term "fifth-generation computers" was devised by the Japanese to describe ___.
A. the intelligent computers they wanted to build by the mid-1990s.
B. artificial intelligence
C. the application of natural languages for inputting data
D. ultra-large-scale integration technologies
Ex. 25. Three words in each sentence should be replaced by another one. Try to do it!
The switches in the first-generation computers were bulky, reliable, time-consuming devices generating large amounts of heat.
The vacuum engineers of one machine generated enough electricity to power a huge town.
The invention of the transistor in 1947 resulted to the creation of smaller, less powerful and faster computers known as microcomputers.
Minicomputers were operated by specialized techniques, which were rarely dressed in black lab coats.
There were three types of the second-generation computers such of locomotive-sized supercomputers and refrigerator-sized minicomputers.
The invention of the integrated circuit in 1957 marks the ending of the third generation of microprocessors.
Microcomputers – systems smaller than portable television programs yet with large computing capabilities – began to be called personal mainframes.
Microprocessors are used in analogue watches, pocket calculators, ENIAC computers, steam ovens, mobile telephones, spaceships, Global Positioning System devices.
TEXT FOR ADDITIONAL READING
Ex. 26. Read the text and reconstruct the paragraphs of the text in logical sequence.