购买
下载掌阅APP,畅读海量书库
立即打开
畅读海量书库
扫码下载掌阅APP

Unit 2
The Early History of Computers
计算机史

One of the first occurrences of computer technology occurred in the USA in the 1880s. It was due to the American Constitution demanding that a survey be undertaken every 10 years .As the population in the USA increased, it took an increasing amount of time to produce the statistics. By the 1880s, it looked likely that the 1880 survey would not be complete until 1890.To overcome this, Herman Hollerith (who worked for the Government)devised a machine which accepted punch cards with information on them. These cards allowed a current to pass through a hole when there was a hole present.

Hollerith's electromechanical machine was extremely successful and used in the 1890 and 1900 Censuses. He even founded the company that would later become International Business Machines(IBM) :CTR(Computer Tabulating Recording). Unfortunately, Hollerith's business fell into financial difficulties and was saved by a young salesman at CTR, named Tom Watson, who recognized the potential of selling punch card-based calculating machines to American business. He eventually took over the company, and, in the 1920s, he renamed it International Business Machines Corporation(IBM).After this, electromechanical machines were speeded up and improved. Electromechanical computers would soon lead to electronic computers, using valves.

The first electronic computers were developed, independently, in 1943;these were the“Harvard Mk I”and Colossus . Colossus was developed in the UK and was used to crack the German coding system whereas“Harvard Mk I”was developed at Harvard University and was a general-purpose electromechanical programmable computer. These led to the first generation of computers which used electronic valves and used punched cards for their main, non-volatile storage .

The world's first large electronic computer(1946), containing 19000 values, was built at the University of Pennsylvania by John Eckert during World War II. It was called ENIAC(Electronic Numerical Integrator and Computer) and it ceased operation in 1957.By today's standards, it was a lumbering dinosaur and by the time it was dismantled it weighed over 30 tons and spread itself over 1500 square feet. Amazingly, it also consumed over 25 kw of electrical power but could perform over 100000 calculations per second(which is reasonable, even by today's standards).Unfortunately, it was unreliable, and would only work for a few hours on average, before a valve needed to be replaced. Faultfinding, though, was easier in those days, as a valve, which was working, would not glow, and would be cold to touch.

Valves were fine and were used in many applications, such as in TV sets and radios, but they were unreliable and consumed great amounts of electrical power, mainly to the heating element on the cathode . By the 1940s, several scientists at the Bell Laboratories were investigating materials called semiconductors, such as silicon and germanium. These substances only conducted electricity moderately well, but when they were doped with impurities their resistance changed. From this work, they made a crystal called a diode, which worked like a valve, but had many advantages, including the fact that it did not require a vacuum and was much smaller. It also worked well at room temperatures, required little electrical current and had no warm-up time. This was the start of microelectronics.

One of the great revolutions of all time occurred on December 1948 when William Shockley, Waiter Brattain, and John Bardeen at the Bell Labs produced a transistor that could act as a triode. It was made from a germanium crystal with a thin p-type section sandwiched between two n-type materials. Rather than release its details to the world, Bell Laboratories kept its invention secret for over seven months so that they could fully understand its operation. They soon applied for a patent for the transistor and, on 30 June 1948, they finally revealed the transistor to the world . Unfortunately, as with many other great inventions, it received little public attention and even less press coverage(the New York Times gave it 41/2 inches on page 46).It must be said that few men have made such a profound change on the world, and Shockley, Brattain, and Bardeen were deservedly awarded the Nobel Prize in 1956.

In 1959, Fairchild Semiconductor filed for a patent for the planar process of manufacturing transistors. This process made commercial production of transistors possible and led to Fairchild's introduction, in two years, of the first commercial integrated circuit . Within a few years, transistors were small enough to make hearing aids that fit into the ear, and soon within pacemakers. Companies, such as Sony, started to make transistors operate over higher frequencies and within larger temperature ranges. Eventually, they became so small that many of them could be placed on a single piece of silicon. These were referred to as microchips and they stared the microelectronics industry. The first two companies who developed the integrated circuit, were Texas Instruments and Fairchild Semiconductor. At Fairchild Semiconductor, Robert Noyce constructed an integrated circuit with components connected by aluminium lines on a silicon-oxide surface layer on a plane of silicon. He then went on to lead one of the most innovative companies in the world, the Intel Corporation.

In the same year, IBM built the first commercial transistorized computer named the IBM 7090/7094 series, which dominated the computer market for many years. In 1960, in New York, IBM went on to develop the first automatic mass-production facility for transistors. In 1963, the Digital Equipment Company(DEC) sold their first minicomputer, to Atomic Energy of Canada. DEC would become the main competitor to IBM, but eventually failed as they dismissed the growth in the personal computer market.

The second generation of computers started in 1961 when the great innovator, Fairchild Semiconductor, released the first commercial integrated circuit. In the next two years, significant advances were made in the interfaces to computer systems. The first was by Teletype, who produced the Model 33 keyboard and punched-tape terminal. It was a classic design and was on many of the available systems. The other advance was by Douglas Engelbart, who received a patent for the mouse-pointing device for computers.

The production of transistors increased, and each year brought a significant decrease in their size. Gordon Moore, in 1964, plotted the growth in the number of transistors that could fit into a single microchip , and found that the number of transistors that can be fit into an integrated circuit approximately doubled every 18 months. This is now known as Moore's law , and has been surprisingly accurate ever since. In 1964, Texas Instruments also received a patent for the integrated circuit.

The third generation of computer started in 1965 with the use of integrated circuits rather than discrete transistors. IBM, again, was innovative and created the System/360 mainframe. In the course of history, it was a true classic computer. Then, in 1970 IBM introduced the System/370, which included semiconductor memories. All of the computers were very expensive(approx.$1, 000, 000), and were the great computing workhorses of the time. Most companies had to lease their computer systems, as they could not afford to purchase them. As IBM happily clung to their mainframe market, several new companies were working away to erode their share. DEC would be the first, with their minicomputer, but it would be the PC companies of the future who would finally overtake them. The beginning of their loss of market share can be traced to the development of the microprocessor, and to one company:Intel. In 1967, though, IBM again showed their leadership in the computer industry by developing the first floppy disk. The growing electronics industry started to entice new companies to specialize to key areas, such as International Research who applied for a patent for a method of constructing double-sided magnetic tape utilizing a Mumetal foil inter layer .

In 1968, Douglas C. Engelbart, of the Standford Research Institute, demonstrated the concept of computer systems using a keypad, a mouse, and windows at the Joint Computer Conference in San Francisco's Civic Center. He also demonstrated the use of a word processor, a hypertext system, and remote collaboration. His keyboard, mouse, and windows concept has since become the standard user interface to computer systems.

In 1969, Hewlett-Packard branched into the world of digital electronics with the world's desktop scientific calculator:the HP 9100A. At the time, the electronics industry was producing cheap pocket calculators, which led to the development of affordable computers, when the Japanese company, Busicom, commissioned Intel to produce a set of between 8 and 12 ICs for a calculator. Then instead of designing a complete set of ICs, Ted Hoff, at Intel, designed an integrated circuit chip that could receive instructions, and perform simple integrated functions on data. The design became the 4004 microprocessor. Intel produced a set of ICs, which could be programmed to perform different tasks. These were the first ever microprocessors and soon Intel produced a general-purpose 4-bit microprocessor, named the 4004.

The 4004 caused a revolution in the electronics industry as previous electronic systems had a fixed functionality. With this processor, the functionality could be programmed by software. Amazingly, by today's standards, it could only handle 4 bits of data at a time(a nibble), contained 2000 transistors, had 46 instructions and allowed 4KB of program code and l KB of data. From this humble start, the PC has since evolved using Intel microprocessors. Intel had previously been an innovative company, and had produced the first memory device(static RAM, which uses six transistors for each bit stored in memory), the first DRAM(dynamic memory, which uses only one transistor for each bit stored in memory)and the first EPROM(which allows data to be device, which is then permanently stored).

In 1974, Intel was a truly innovative company, and was the first to develop an 8-bit microprocessor. These devices could handle 8 bits(a byte)of data at a time. These were much more powerful than the previous 4-bit devices and were used in many early microcomputers and in applications such as electronic instruments and printers. The 8008 had a 14-bit address bus and could thus address up to 16KB of memory, and the 8080 and 8085 had 16-bit address buses, giving them limit of 64KB. At the time, Intel's main product area was memory, and microprocessors seemed like a good way of increasing sales for other product lines, especially memory.

Excited by the new 8-bit microprocessors, two kids from a private high school, Bill Gates and Paul Allen, rushed out to buy the new 8008 device. This they believed would be the beginning of the end of the large, and expensive, mainframes(such as the IBM range)and minicomputers. They bought the processors for the high price of$360(possibly, a joke at the expense of the IBM System/360 mainframe), but even they could not make it support BASIC programming. Instead, they formed the Traf-O-Data company and used the 8008 to analyze tickertape read-outs of cars passing in a street. The company would close down in the following year(1973)after it had made$20000, but from this enterprising start, one of the leading computer companies in the world would grow:Microsoft.

In 1975, Micro-soft(as it was known before the hyphen was dropped)realized the potential of BASIC for the newly developed 8-bit computer and used it to produce the first programming language for the PC. Their first product was BASIC for the Altair, and licensed it to MITS, their first customer. The MITS, Altair 8800 was a truly innovative system and sold for$375 and had 1 KB memory. Soon Microsoft BASIC 2.0, for the Altair 8800, was available in 4K and 8K editions. The Altair was an instant success, and MITS began to work on a Motorola 6800-based system. Even its bus became a standard:the S100 bus.

The third generation of microprocessors began, in June 1976, with the launch of the 16-bit processors, and it was on May 1978 that Intel released the 8086 microprocessor. This processor was mainly an extension to the original 8080 processor and thus retained a degree of software compatibility.

1985 was the year that Microsoft released their first version of Windows, at a price of$100.It was hardly starting, and would take another two versions before it completely dominated the market. It could not multitask, and still used DOS. Another major failing was that it did not use the full capabilities of the new 32-bit processor(80386)or the enhanced 16-bit processor(80286), and could thus only access up 1 MB of memory.

Microsoft had over the past few years initiated many new products for both the IBM PC, and the Apple Macintosh. In 1985, they consolidated their market with new versions of the successful software, such as MS-DOS 3.2 and Microsoft Word 3.0.In MS-DOS 3.2, support was added for 3.5-inch 720 KB floppy disk drives(these disks were much more reliable than the older, “floppy”, 5-inch floppy disk, as they had a hard case to protect them).The initial investment of time, and energy, for those involved in Microsoft was rewarded when, for the first time, Microsoft sold its shares to public. When floated, each share was worth$21, which raised$61 million for Microsoft, and made Bill Gates the world's youngest billionaire.

Exercises

I. Choose the best answer :

1. Herman Hollerith devised an electromechanical machine in order to_____.

A. save time

B. accept punch cards

C. allow a current to pass through a hole

D. produce the statistics of the population

2. From the second paragraph, we know_____.

A. Hollerith was a good businessman

B. International Business Machines was the original name of the company Hollerith set up

C. Watson was business-minded

D. Hollerith's machine found little use in the 1890 census

3. What does ENIAC as an acronym stand for?

A. Electronic Numerical Integrator and Computer

B. Electronic Number Interface Analysis Computer

C. Electronic Number Interface and Computer

D. Electronic Numerical Interchange and Computer

4. What was not true of the first electronic computers?

A. Harvard MK I was general-purpose electromechanical programmable computer.

B. Colossus used electronic valves.

C. They used punched cards for their main, non-volatile storage.

D. Scientists in the U. K.and the U. S.A worked together in 1943 to develop the first electronic computers.

5. The world's first large electronic computer(1946)_____.

A. was built after the World War II

B. was used for over 10 years

C. contained 25000 valves

D. could perform only 10000 calculations per second

6. One of the great revolutions of all time that occurred in 1948 was_____.

A. the invention of a transistor

B. the discovery of silicon

C. the production of a crystal called a diode working like a valve

D. the beginning of the start of microelectronics

7. Which of the following is not true?

A. In 1959, IBM made its first commercial transistorized computer.

B. In 1961, the first commercial integrated circuit came into being.

C. In 1962, the second generation of computers started.

D. In 1963, the first advance was the production of the Model 33 keyboard.

8. Gordon Moore_____.

A. fit a number of transistors onto a single chip

B. put forward his law, that is, the number of transistors fitted onto an integrated circuit approximately doubles every 18 years

C. received a patent for the integrated circuit

D. found his law surprisingly accurate

9. Which of the following is true?

A. The third generation of computer started in 1966.

B. Intel devised the System 370 that contained semiconductor memories in 1970.

C. IBM developed the first floppy disk.

D. Since 1969, keyboard, mouse and windows concepts have become the standard user interface to computer systems.

10. From the text, we learn that in 1985_____.

A. Microsoft released their first version of Windows at$100

B. Microsoft gave another version of MS-DOS 3.2

C. Microsoft sold its shares to the public first

D. All of the above

II. Answer the following questions :

1. When did computer technology first occur and why did it happen?

2. When was International Business Machines founded?

3. Why was the world's first electronic computer called a lumbering dinosaur?

4. What were the disadvantages of valves?

5. What achievements were made at the Bell Labs in 1948?

6. When did the second generation of computers start?

7. What were the differences between the second generation of computers and the third?

8. What made Bill Gates the world's youngest billionaire? +RYO8WHpGvjNW+qSHQ7Q9XI7jm0sH93M1HHSSr01PfJhXm8sjaEGIbRcBk7Z839L

点击中间区域
呼出菜单
上一章
目录
下一章
×