Английский язык 3 семестр ВФ (тексты + перевод) / Units 01-12

1'1

A comp\lter is a machine wilh an intricate network of electronic

circuits that operate switches or magnetize tiny metal cores. The

switches, like the cores, are capable of being in one of two possible

states, that is, on or off; magnetized or demagnetized. The machine is

capable of storing and manipulating numbers, letters, and characters.

5

The basic idea of a computer is that we can make the machine do what

we want by inputting signals that turn certain switches On and turn

others off, or that magnetize or do not magnetize the cores.

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The basic job of computers is the processing of information. For this

reason, computers can be defined as devices which accept information

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in the form of instrUctions called a program and cbaracters called data,

perform mathematical and/or logical operations on the information, and

chen supply results of these operations. The program, or part of it,

which tells the computers wbatto do and the data, which provide the

information needed to solve the problem, are kept inside the computer

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in a place called memory.

(31

Computers are thought to have many remarkable powers. However,

most computers, whether large or small have three basic capabilities.

First, computers have circuits for performing arithmetic operations,

such as: addition, subtraction, division, multiplication and

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exponentiation. Second, computers have a meanS of communicating

with the user. Mter all, if we couldn't feed information in and get

results back, these machines wouldn't be of much use. However, certain

computers (commonly minicompuier.s and microeomputer.s) are used to

control directly things such as rpbots, aircraft navigation systems,

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medical instruments, etc.

[41

Some of the most common methods of inputting information are to use

punched cards, magnetic tape, disks, and terminals. The computer's

~

Magnetic

Computer

tape

~I::::::::::IQ"OO

llllllllllfll"'numllill

Input device

1''''111'''' ..""11

1II11II1lInil.IUIU...

Magnetic

E3 disk

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[11 Let us take a look;H the hiswry of the computers that we knO\'.' today.

The vc'ry first c:Jlculaling device used was the ten fingers of a man's

hands. This, in fact) is \vhy today we still count in tens and multiples of

tens. Then the abacus wa:-i invented, ;) bead frame in which the beads

are moved from left to right. People went on using sume form of abacus

5

well into the 16th cemury, and it is still being used in some pans of the

world because it can bl.: understood \vithout kno\',.'ing how to read.

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During the 17th and 18th centuries many people tried to find easy ways

of cal:\..d8.ting. J. Napier, a Scotsman, devised .a mech.mical way of

multiplying and dividing, which is how the modern slide rule works,

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l-leIll'y Briggs used Nopic,'s ideas to produce logarithm tables which all

mathematicians usc today. Calculus, another branch of mathematics,

,vas. indepcndently invcnted by both Sir Isaac Newton, an Englishman,

and Lcibnitz, a Gcrm~!n mathematician.

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The first real cidculating machine appeared in 1820 ~lS the result of

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sc\'eral pcople's experimcnts. This type of machinc, which saves a great

deal of time and reduces the possibility of making mistakes, depenJs on

a scries of ten-toothed ge~H wheels. In 1830 Charles Babbage, an

Englishman, designed a machine that was called The Analytical

Engine'. This machine. which Babbage showed at th~ Paris Exhibition

20

in l855, was an attempt to Cllt out the human being altogether, except

for providing the machine with the necessary facts about the problem w

be solved. He never finished this work, but many of his ideas were the

basis for building tod~IY's computers.

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In 1930, the first analog computer was built by all American narneu

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"annevar Bush, This device wos used in World War 11 to help aim

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to 4 mc ,upon WlllCh several layers 0

an 1lltegrate

CIrcuit arc eldlCll

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,--.J ~. \....omputers lave n<1

a very:, lOl'l lJ,;;;l1.:1 l'y ,

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, .-::h-;" d di,. j

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comparisons is called processing. Compmers arc made up of millions of

5

electronic devices capable of storing data or moving them, at enormous

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speeds, through complex circuits witn different functions.

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12J All computers have several characreristics in common, regardless of

I

make or design. lriformation, in the form of instructions and data, is

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given to the machine, after which the machine acts on it, and a result is

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, then Tcmnied. The information presented to the machine is the input;

the internal manipUlative operations, the processing; and the resuh, the

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I

output. These three basic concepts of input, processillg, and output

occur in almost every aspect of human life \vhether at work or at play.

I

For example, in c10lhing manufacturing, the input is the pieces of cut

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~loth, the processing is the sewing wgether of these pieces, and dIe

,

output is tne finished garment.

[NPUi}------> [CO~PU~ER-~ @UTPUy]

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[SEc ST(lRA~

Figure 3.1

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;

PI Figure 3.1 shows schematically the fundamental hardware components

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in a computer system. The centerpiece is called either the computer) the

processor, or, usually, the central processing unit (CPU). Tne term

'computer' includes those parts of hardware in which calculations and

,

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other data manipUlations arc performed, and thc high-speed internal

memory in whkh data and calcularions are slored during actual

e:<ecutjon of programs. Attached to the CPU are the various peripneral

devices such as card readers and keyboards (two commOn examples of

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input devices). When data or p ograms need to be saved for long

periods of time, they are stored on varjous secondary memory devices

or storage devices such as magnetic tapes or magnetic disks.

141 Computers have often been thought of as exrremcly large adding

machines, but this is a very narrow view of their function. Although a

3D

computer can only respond 10 a certain numba of instructionsl it is not

a single-purpose machine si ..1ce [hese instructions can be com bined in

an infl!1ite number of sequences. Therefore, a COmpLlter has no known

limit on the kinds of things It can do; ils vcrsatility is limircd only by

the imaginalion of those using it.

3S

151

[n the late 19505 and early 1960s ·when eleclronlc compurers of the kind

in use today were being developed, they were: very expensive to own and

run. Moreover, their size and reliabiUty \vae such that a iarge number

of support personnel were needed to keep [he equipment operating.

This has all changed now that com putjug power has become portable)

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more compact) and chcaper.

[61

In only a very shan period of time, computers have greally cnanged 'hc

way in which many kind, of work are performed. Computers can

remove many of (he routine and boring tasks from our lives) thereby

Jeaving us with more time for inreresling, creauve work. It goes withom

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saying that computers have created whole new areas of work that did

not exist before their development.

U

1.

Computers have changed [he W<lY in which we live.

0

2.

All computers have an input, a processor, an outpUt and a

stora'ge device.

0

3.

Ccrmpurers have decreased mar~'S workload.

0

4.

All computers have the same basic hardw:lre components.

lllhelJ you ,.ead tile lollowillg le_([

I"c1J!I'!JIher 10 Ily alld Imderslm/(! (he

mealli"g of Hew words lmri expreSSlOllS fro'll the cOI/lext. Don't check new

words ill the diCliollmy IImil yon bail/] rend Ihe whole text. NloH of ,he 'Words

ill bold rypejilce are o.:plaillcJ In

the G/05Sll1)' al rhe end of the book.

III

Like all J]1;.Jchines, ~ compuler needs 10 be dirccleJ and cOIllrolled in

order [Q perform a taSk successfully. UmiJ such time as a program is

prepared and stored in the computer's memory, the computer 'knows'

absoJUlely nothing, nO[ even how lq accept Or reject data. Even the mosl

sophisticated computer, no n'larter ho'w cap;.Jble il is,.mus[ be wid what

s

to do. Unril (he capabilities and II\(: limitations of a computer <lre

recognized, its usefulness cannot be lhoroLighly understood.

121

In the first place, it should be recugnize"d

lhal computCfs 3re c~pable of

doing repetiliv"e operations. A COlllpllll.:r can pe~formsimilar operations

. '

.

.'f "~/I'" ... <I,

thousands 'If urnes, withom bec0\1\Ing: bored, llred, or even 'careless.

10

PI Secondly, compUlers can process inform.nioH 3.t extremely rapid rates"

For example l modern computers can solve cCriain classes of arirhmelic

problems millions of times fuster thall LI skilled m~Hhemalician.Speeds

fOf performing decision-making operations i\rC comparable lo those for

arithmetic operations bm infut-output operations) however) involve

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mechanical motion and ReAce Ir~uirc more time. On a typical computer

r,.:Jt"(

system) cards are read at an average speed of 1000 cards pe.r minute am.!

as many as 1000 lines can be printed ,H the same rate.

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Thirdly, complIIcrs may be progr<lll1mt.:d 10 calculate answers to

whatever level of accuracy is speciJicd b~t"9"e.programmer,In spite of

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newspaper headlines su.ch as 'Colll{)lI[er fairs') these machines arc very

accurate and reli.able especially whell lhe number of operarions they c;ln

perform every second is considereJ.. ilee-luse (hey are man-maJe

machines, they sometimes malfunclion or break down and have lO be

repaired. However, ill mos[ instances when the computer fails l it is Juc

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to human error anJ. is not the fault of the computer ar all.

i

{51 In the fourth place, general-purpose computcrs can be progr:lmmed to

solve various types of problems because of their flexibility. One of the

moSl important reasons why computers are so wiJely used roday is lhat

,Imost every big problem can be solved by solving a number of III tie

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problems - one after another.

[61 Finally, a computer, unlike a human being, has no intuitio~. A person

may suddenly find the answer to a problem without working out 100'

many of the details, but a computer can only proceed as it has been

programmed to.

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payroll. Firsr: Input informalion abOUI ~~~!1.~r~ox~esuch as wage rate,

hours worked, tax rate, unemployment Insurance, and pensIon

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I. A computer cannot do anything Ulud it has been

programmed.

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2,

A compurer is a useless macbine if its capabilides and

limitations are unknown.

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0

3,

A computer can repeat the same operarion over and over

again forever if permilled.

1"

in order to use computers effectively to solve problems in our

environment, computer systems are devised. A 'system'lrtlj11ie:a good

mixture of int~gratedparts working together to form a useful whole.

Computer systems may be discussed in two parts.

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The first part is hardware ­

the physical. elecuonic, and

5

cleclromechaniLal devices thar are thought of and recognized as

·computers'. The second pan is software - lhe programs lhal control

and coordinate lhe activities of the c'Omputer hardware and that direl:t

the processing uf data.

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_I n.,pu, -"1

Input

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~1 5.wnd.~"o'age Ej

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F'gl.lr~ 5.1 Hardware components of 8 baSIC computer system

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Figure 5.1 sh'lw"S Jiagraitunatkally the basic wmpcnents of computer

manipulations are perfonned, and to the internal memory in which data

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and instructions arc stored during the actual ex:ecuti(ln of programs. The

various peripherals, which include input and/or output devil'es, variou!'

secondary Dlemory devices, and so Oil, arc allRchcd to lhc CPU.

14 '

Computer soltware can be divided into two ve~ broad categories­

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syste;ms software and applications softwaceJl1te fOIDlcr is often

simply refen nt to as ·systems·. These, whcn brought imo intem.al

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1.

A system implies a good mixrure of pans working

log-ethel.

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0

2.

Input and output devices operate more slowly than the

decision-making devices.

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0

3.

The control unit and the <lrithuletil.>logical unit arc part

of I he prol'CSSor.

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0

4.

The 'computer'is the hardware.

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5.

Softw:uc is the programs pn cards:l.apcs and disks.

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6.

The processor is usually refl;rrct..l lU as fhe CPU.

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7.

The word 'I.:omputcr' means the processor and the

internal memory.

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8.

~ys{ems software is USU;J!ly reft.:rr('d {o as programs.

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9.

Complete hardware/software products arc callt-d Illrnkev

systems

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10.

Com pUlers process specially prepared ilcHl~ of

informillion.

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Large computer SYSten1S J or mainframes, as they are referred to i.r

t11':

'field of computet science,'3re those computer systems found in

computer inHtallatiOD& processing immense amounts of dam. 'the~~ ~

powerful CODlputers make use of very high-speed main memories L r.o

which data and programs to be dealt with are lransferred for 11lpid

,

access. TheSl: powerful ma~hines have a larger T~renoire of more

complex instructions which can be executed morc"quickly. WherU':

smaller comJluters may take several steps to perform a particuJar

operation, a iarger mach.io.e may accomplish the same thing with (.,~

1ll!uucuon.

10

[2J These computers am be of two types: digital or a.a1og. The digit..

computer or general-purpose computer as it is often known, makes uP,

about 90 per cent of the large computers now in use. It gets its name

because the data that are presented (0 it are made up of a code

consisting of digits -~s.i.ngle<hBracternumbers. The digitaJ computl~r is

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like a gigantic cash regiSter in that it can do calculatioDs in steps, one

after another at lrernendous speed and with great accuracy. :Digital

computer pr-:>gramming is by far the most commonly. used in elccrrowc

data proceS!,ing for business or stal.j,~ticaJpurpoSes.IThe analog

computer w(,rks something like: a car,Jpeedometer, in that it

2CI

continuously works oUt calculations. 'If" is used essentially for problems

involving m(uuremcnts. it can simulate, or imitate different

mC3Surements by electronic mc;ans. Both of these computer types -

r.he

digital and the analog - are made up of elccuomc components w( may

require a 1ar:se room to acc~mmoda(ethem. At present, the digital

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(."()wputer is capable of doing anything the analog once did. Mrl-c: . .er, i~

is euicr to program and cheaper to operate. A new type of scl:r.ij

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computer s:9sIaIl called the hybrid computer has now been pr<Xi.'.l

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lbat combin~the two types into one.

l3]

Really powerful computers continue to be bulky and require spec. I.!

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provision fo:: their housing, refrigeration sYStems, air fihration aD:

p:>wer supplies. This is because much more space is taken up by t~l-:

input!outpu. devices - the magnetic tape and disk units and othel

periphc:t:a.l o~uipmen[ -{i1.an by the electronic com:PODents that d~

"lOt

UrUl 6 MaillfratMs

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make up the bulk of the machi I ~ in a powerful installation. The power

J5

C(lfiSumption of these machine

::i al~o Quite high) nut to iT.C"~~Gr:. th~

price that runs into hundreds ( : thousands of dollars. The future wdl

bring great developments in d'

: mechanical devices associ,aled '.nth

computer systems. For a long

i.·ne these have been the ww link, from

the point of view of both effici .n(y and reliability.

"

o

1.

Hybrid computers ar·

"combination of digital and analog

o 2.

computers.

.

Digital compucers an

l:.sed more than any other type: of

computer.

D

3.

There are three IYP'"

of mainframes.

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4.

Analog computers ca

d.o more varied work !.han digital ur

hyhrid compute".

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D'O

1.

A mainframe I

the type of compUler !.hat can Sit on top

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,

"fa desk.

2;

Mainframes 8J

: very powerful and can execute jobs very

rapidly and .. ;ily.

DO 3.

Digital compl :rrs arc used more than analog computers.

00 4.

The analog cc· nputer is far smaller than a dJgitaJ

computer ani

jl.erefore occupies very little space.

00 5.

The bybrid a

Citputer is a combination of botll the digital

and the malo

:omputer.

DO

6.

The analog c(· I1pucer does irs ca.lcularions one step at a

time.

II]

Until the mid-l%Os, digital computers wen: powerful, physically large

and expensive. What was. really needed though, were computers of iess

power, a smaller memory capacity and widlout such a large array of

peripheral equipment. This need Was partially satisfied by the tapid

improvemem .in performance of the semi-conductor devices

5

(transistors), and their incredible reduction in size, cost and power; all

of which led ro the development of me minicomputer or mini for shan.

Altbough there is no exact definition of a minicomputer, it is generally

understood to refer to a computer whose mainframe is physically small,

has a fixed word length between 8 and 32 bits and costs less than

10

U.S. $100,000 for the central processor. The IIlllOunt of primary .tor4e

available optionally in minicomputer systems ranges from 32-S12K*

bytes; bowever, some systems allow this memory to be expanded even

further.

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A larze number of peripherals have been developed especially for use in

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systems built around minicomputers; they are sometimes refened to as

rniniperipherals. These include mapetie tape cartridges and

eassettes, small disk units and a large variety of prt."lteI'S and consoles.

131 Many minicomputers an: used merely for a fixed application and run

only.a single progrnm. This is changed only when necessary either to

'"

concet errors or when a change in the design of the system is

introduced.. Since the operating environment for most minis is far less

varied and complex than large mainframes, it goes without saying that

the software and peripheral requirements differ greatly from those of a

computer which runs several hundred ever-changing jobs a day. Tbe

2S

operating systems of minis also usually provide system access to either a

.single user or to a limited number of users at a time.

purpose. For example. most minis have an interrupt feature which

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Urril 7 Milliamlputerr

73

to resume operation after it has responded 10 the interruption. Because

"

minicomputer systems have been used so often in real~timeapplicatioDs,

other aspects of their design have changed; that is, they usually IX\ssess

the hardware capability to be connected directly to a large variety of

measurement insuumentsJ to analog and digital converters, to

microprocessors, and ultimatelyJ to an even larger mainframe in order

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to analyse the collected data.

.. lK is defined as 2ID = 1024; mus 3lK == 32 x 21D = 2~ x

2w =2H = 32,768.

S

NS

0

0

I. The rapid development of transistors led to the

development of minicomputers.

0

D

2.

A minicomputer is said to be very much the same as a

mainframe.

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0

3.

Special peripheral devices have been devdoped to go

with minicomputers.

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4.

Minicomputers can understand more man one computer

language.

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C

5.

Mainframe operating systems usuaJly provide acceSS to a

number of users at lile same time.

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0

6.

Minicomputers have spa.ialized features because of the

operations they execute.

arithmetic functions of a computer are manufactured as a single chip.

5

A complete microcomputer system is composed of a microprocessor. a

memory and peripheral equipment. The processor, memory and

electronic controls for the peripheral equipment are usually put together

on a single or on a few printed circuit boards. Systems using

microprocessors can be hooked up together to do the work that 'mtil

10

recently only minicomputer systems were capable of doing. Micros

generally have somewhat simpler and less flexible instruction sets than

minis, and are typically much slower. Different micros are available

with 4-,8-, 12-, 16-bit word lengths, and some new ones use 32-bit

chips. Similarly, minis are available with word lengths up to 32 bits,

15

Although minis can be equipped with much larger primary memory

sizes, micros are becoming more powerful and converging witll

minicomputer technology.

application for computers. Only 20 years or so ago, a central processing

unit of medium capability sold for a few hundred thousand dollars

20

(U.S.), and now some microprocessors sell for as cheaply as $10. or

course, by the time you have a usable microcomputer system, the price

will be somewhere between $200 and $5000 depending on the display

unit, secondary storage, and whatever other peripherals are need\jd.

[3] The available range of microcomputer systems is evolving more rapidly

25

than minicomputers. Because of their incredibly low price. it is now

possible to use only a small fraction of the computer's capabilit)' in a

particular system application and still be far ahead financially of any

other way of getting the job done. For example, thousands of industrial

robots are in use today, and the number is growing vel)' rapidly a, this

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relatively new industry improves the price and performance of it'

products by using the latest microcomputers.

can also be written for specialized tasks cyen as complex as na\'lgating

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rockets. Some modern micros are even c~pJ.ble t,f multi-1asldng. In

addition to their extensive use in control systems of all type",. the: arc

destined for many new uses from mort: complt:x calculator,;, to

automobile engine operation and medical diagnostics. The'} are

already used in automobile endssion control ~ystenH and are the basis

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of many TV game attachments. There is. also a rapidly growing markcl

no means been reached. There are thos~ who pl'cdi...:.t that the hom!,.': lind

45

o

I,

Microcomputers will be every \\'here in the future.

o

2.

There is no limit to what microcomputers call do,

o

3.

Microcomputers are chep. reliable and efficient

o

4.

Microcomputers for supt:rior to mmicomputers.

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o

0

1.

Microcomputers wen; developed ..~ficr plinkomputers.

o

0

2.

The processor of a microcomputer is printed on a chip.

o

0

3.

A mainframe uses more pO\Yt:r than a micrOl.'Ompul~1.

o

0

4.

Microcomputers fan do the \\'ork done by

o

minicomputers.

0

5.

Microcomputers ha\le the same memory cara~~jly a~

minicomputers and Lan he hooked to a varic!.) \)f

perpherials

IG\ Programs and the data on which lhc L:Ollllll! unil and

Ihe J\L\lll]'Cl<lIC.

j

lllwa be in illlernn( mcmory ill order III bc pn,<,:c$!;cd. ThHS, ;/ hl(;llcd

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sccond;lry l11emory dCl.'ices s\tch as Jisk$ (11 l~lP\'S,

pl~)gral11~ "Ild ~bLl

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first hladed 11110 illlerllal t1IUIli.XY.

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Tht celllr<l\ processing unit is ID;"lJe: up of lhree

CQlllpone:nts.

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2.

Tho::: CPU is rc<:;pollsiblc fQr allihe actidlies laking pltt..::c

wiLhin ~ computer_

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3.

The processor ilsdf hets three components.

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<1.

The: cOfllroluni, Jirecls Ihc flow of inform~tioll within

the processor_

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S. The arithwclic-Iogical unit of the processor is respomnbl'

fOJ !he illlerprctation of program instructions.

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6.

The: arjthme:tic-!ogical unit is also re:sponsi\:lle for

chnosing :md COlllp<tril\f;t the ~ppr(lpri<1!(, inforrl13fioll