试用计算机英语

21世纪高等职业教育通用教材

实用计算机英语

主编饶文涛

副主编李军周天宏

主审李万华

上海交通大学出版社

内容提要

本B用英语介绍了计算机的主要硬件和一些常用软件，以及计算机网络知识。内容如卜.：硬

件知识主要包括中央处理器、主板、芯片组、显卡、声卡、多媒体、打印机、硬盘和显示器等；

软件知识包括了操作系统如DOS、Windows,Linux,常用软件AUTOCAD、FOXPRO和MATLAB

等；网络知识主要包括和Network、Internet、E-mail、BBS等方面知识。本教材所使用的材料力求

能反映当前计算机技术的新发展。

本书内容比较浅显，但覆盖的计算机知识面较广，也比较实用，适合计算机类和工科类高职

学生使用：也可以供广大计算机爱好者和读者参阅。

书名：实用计算机英语

作者：饶文涛

出版社：上海交通大学出版社

ISBN7-313-03398-2

中图分类号H687

刖百

对于高职的计算机专业英语教学而言，编写一本比较合适的教材十分必要，因此我们编

写这本作为探索。

高职的计算机英语教材该是怎样、包括哪些内容、深浅程度如何，都是我们一直在思考

的问题。我们有关的任课教师经讨论一致认为：教材一定要适合大部分高职学生的实际水平,

这包括两个方面：首先，要考虑他们的实际英语水平，希望学生借助词典就能看懂教材，不

觉得很困难；其次，所选内容必须是他们这一层次的，这样才能学以致用，而且所选的内容

一定要使学生感兴趣，学生不仅能学到专业英语词汇，而且扩大了知识面，并能获得一些有

趣的小知识。教材在内容上也应分层次，对于英语水平较高的和感兴趣的学生，应为他们收

集一定数量的有关技术的阅读材料，供他们课余时间阅读，提高他们的实际阅读能力。

本教材的使用对象是高中后受过两年高职普通英语教育的高职学生，他们已掌握相应的

基本英语词汇和常用语法。

本教材的授课时数为60〜70学时。经过学习，学生能掌握数百个科技和专业词汇，基本

上能看懂有关计算机及其零部件的说明书和广告，能基本理解各种软件的操作提示和帮助说

明，能上网浏览计算机英语世界。

本教材经过两个学期的试教，实践证明效果不错，一些学习认真的学生在100分钟的考

试中完成3页7000多词的专业翻译。现在在这基础上又做了修改，充实了许多新内容，更新

了部分陈旧、过时的内容，使可读性更强。经过测试和评估，只要学生认真学习，可以对今

后的继续深造、学习英文的原版教材和专业资料，打下一个很好的基础。

参加本书编写的有武汉职业技术学院的饶文涛、饶成，河北工、业职业技术学院的李军和

哪阳师范高等专科学校的周天宏等同志，由饶文涛统稿。

李万华同志的仔细审稿减少了许多错误，不胜感谢。

由于时间紧，教材专业性强，编者水平有限，书中难免存在错误，恳请广大同行指正。

编者

2003年5月

CONTENTS

CHAPTER1INTRODUCTION1

1.1WHATISACOMPUTERSYSTEM1

1.2DIVISIONOFCOMPUTERS4

1.3COMPUTERCODES8

CHAPTER!HARDWARE11

2.1PROCESSOR11

2.2STORAGEHIERARCHIES,RAMANDROM15

2.3INPUT/OUTPUTDEVICES,MOUSE,KEYBOARD,PRINTER19

2.4MONITOR22

2.5MAINBOARD27

2.6CHIPSET32

2.7VIDEOADAPTERCARD35

2.8AUDIOADAPTERCARD38

2.9HARDDISK40

2.10MULTIMEDIA,CDROM45

2.11BIOS48

CHAPTER3OPERATINGSYSTEM51

3.1OPERATINGSYSTEM51

3.2DOS55

3.3WINDOWS58

3.4LINUX64

CHAPTER4POPULARSOFTWARES70

4.1PROGRAMMINGLANGUAGES70

4.2AUTOCAD74

4.3FOXPRO77

4.4MATLAB82

CHAPTERSNETWORKS86

5.1COMPUTERNETWORKSSUMMARY86

5.2FOUNDATIONOFNETWORKS94

5.3EXAMPLESOFNETWORKS104

1

5.4INTERNET112

5.5APPLICATIONSOFINTERNET118

5.6VIRUS124

APPENDIXlCHINESEVERSION131

1.1计算机系统131

1.2计算机的分类132

1.3计算机编码133

2.1处理器133

2.2存储器的层次结构，RAM和ROM135

2.3输入输出设备，鼠标、键盘、打印机136

2.4显示器137

2.5主板139

2.6芯片组140

2.7显卡141

2.8声卡142

2.9硬盘143

2.10多媒体、光驱144

2.11基本输入输出系统146

3.1操作系统147

3.2DOS148

3.3WINDOWS149

3.4LINUX150

4.1编程语言152

4.2AUTOCAD154

4.3FOXPRO155

4.4MATLAB157

5.1网络概论159

5.2网络基础161

5.3网络实例166

5.4因特网168

5.5因特网的应用171

5.6计算机病毒173

APPENDIX!ACRONYMLIST177

REFERENCES188

2

CHAPTER1INTRODUCTION

1.1WHATISACOMPUTERSYSTEM

Whatissystem?”System",theterminologyiswidelyusedinactivityfieldsofscience,

technology,economy,culture,education,etc.Systemsappeareverywhere.Asocietyisasystem,a

governmentisasystem,anenterpriseorcompanyisasystem,andaproductionlineisasystem,an

automaticmachineisasystem,andacomputerisasystem.

Asystemmeansagroupofrelatedpartsworkingtogetherinorder.Allthepartsinasystem

arelinkedwith,restricted,interactedanddependedoneachother.

Whatisacomputersystem?Itisaninformationprocessingsystem.Adigitalcomputersystem

consistsmainlyofthreeparts:theinputdevices,theoutputdevicesandthecentralprocessingunit

(CPU)whichcanaccept,storeandprocessdataorsymbolsandyieldoutputresultsfastunderthe

indicationofasetofinstructions.TheFig.1.1givesyouasimpleandperfectshowofthebasic

organizationofacomputersystem.

Fig.1.1

Ifacomputersystemwerecomparedtooneofhumanbeing,theCPUwouldbetheperson's

brain.TheCPUisthekeycoreofacomputersystem,sosomepeopleprefertocallacomputerasan

electronicbrain.Hence,theinputdeviceswouldcertainlybesenseorgansofthepersonfbrsight,

sound,touch,tasteandsmelltodelivertheinformationtothebrain.AftertheCPUprocessingthe

informationacceptedbytheinputdevices,theoutputdevicesgiveouttheresultsusersneed.

Computerworkinginorderdependsonprograms.VonNeumannproposedinitiallythe

programaccessingandcontrollingprinciples.So,theprincipleistitledVonNeumannprinciple.

Theprinciplepointsout:Theinstructionsequence(program)directingthecomputerhowtooperate,

andoriginaldatawillbefirststoredintheinternalmemorydevices.Everyinstructiondefinitely

containstheaddresswhereadatumbeinggotten,whichoperationthecomputerwillexecute,the

locationwheretheresultwillgointhememory.Whenacomputerworks,itfetchesthefirst

1

instructionfromthememory,theID(InstructionDecoder)translatestheinstruction,andittakesa

datumfromthememoryandprocessesthedatumunderthedirectionoftheinstruction.Then,it

sendstheresulttoalocationinthememory.Next,itgetsthesecondinstructionfromthememory

andrepeatsthestepsagainuntiltheprogramends.

Instructionsplaykeyrolesinaprogram.Actually,acomputerhasitsowninstructionsetthat

containsallinstructionsitcanimplement.Aninstructionconsistsoftwoparts:opcodeandoperand.

Opcodemeanswhatkindofoperationthecomputerwillcarryout.Operandrepresentsthedatumor

theaddressofthedatum.

ItistheCPUthatisthemostimportantforacomputersystem.Howdoengineersdesignand

organizetheCPUthen?TheCPUisreallydividedintothreemainpartsdependingontheir

functions:Theprimarystoragesection,thearithmetic-logicsectionandthecontrolsection.Youcan

learntheirfunctionsfromtheirnamesrespectively.

UsershardlytouchCPUs,buthaveusedtheinputdevices.InPCsystems,usersoftenwork

withkeyboards,mice,inputpens,touchscreens,microphonesandothersfordirectinput.

Regardlessoftheirdifferences.Theyarecomponentstomakeinterpretationandcommunication

betweenusersandcomputersystems.Thestoragedevices,floppydiskdrivesandharddisk

drives,arecommonlyusedfbrindirectinput.

Usershavealsoemployedavarietyofoutputdevicessuchasmonitors,printersandplotters,

whichgettheoutcomesfromtheCPUinmachine-codedformandchangethemintotheformsusers

canunderstand.Harddiskdrivesorfloppydiskdrivesoftenrecordtheresultsondisksfbrnextor

anothermachineinput.

Input/outputdevices,floppyandharddiskdrives,monitors,printers,plotters,etc,areoften

togethercalledperipheraldevices(orjustperipherals)forease.

NEWWORDS

inputdevice输入设备

centralprocessingunit中央处理器

store储存

enterprise企业

restricted限制

interacted相互作用的

indication指示

component部件

arithmetic-logicsection算术逻辑段

keyboard键盘

machine-codedform机器码形式

printer打印机

monitor显示器

instructiondecoder指令译码器

2

aseriesofinstructions一串指令

operand操作数

opcode操作码

brain大脑

Primarystoragesection基本储存段

harddiskdrive硬盘驱动器

interpretation解释，翻译

communication通信，交通

floppydiskdrive软盘驱动器

peripheral外围的

plotter绘图机

EXERCISE

1.TranslatethefollowingintoEnglish.

⑴外围设备是人机交流的桥梁。

⑵计算机分成三部分：输入设备、输出设备和中央处理器.

⑶CPU的功能是接受指令和处理数据。

(4)屏幕上的符号反映了人机对话的内容。

(5)计算机的I/O设备包括键盘、鼠标、绘图机、打印机、软盘和硬盘。

2.Writeabriefcompositionofthetexttosumitsmainideain40wordswiththefollowing

words:store,process,input,output,peripheral,floppy,hard,communication.

3

1.2DIVISIONOFCOMPUTERS

Nowadays,Computershavebeenwidelyusedinvarietiesoffields,suchasinindustry,

agriculture,medicaltreatment,science,andlife,etc.Theirapplicationsaresospacious,their

influenceissodeep,andtheirdevelopmentissofastthattheybecomeimportantsignsormarksto

measurethemodernizedlevelofanation.

Multipleapplicationsmakecomputersfallintothatofdifferentproperties,functions,shapes,

size,andevenmanufactures.Therefore,therearediversesortsofcomputersintheworld.For

managementanddevelopmentofcomputers,peoplehavetoclassifycomputersintosorts.But

differentviewpointshavedifferentresultsonthedivisionofcomputertypes.

Traditionally,computersfallintotwocategories:digitalcomputersandanalogcomputers.

Processingnumbersandsymbolsistheworkofthedigitalcomputers;theanalogcomputersonly

workonthecontrolofquantitiessuchaselectricalcurrentsorvoltages.Butnowadays,theformer

willbemorepowerfulandoccupythepositionsofthelater.

Somepeoplepreferringanewwaytoclassifycomputersaimattheirpurposes.Oneisthe

special-purposecomputerthatisdesignedtoperformauniquetask,intoorinwhichaseriesof

instructionsiswiredorpermanentlystored.Itlacksversatilitybutworksquicklyandefficiently.

Ageneral-purposecomputercanstorevarietiesofprogramsandcansobeappliedtocountless

casesorjobs.

Althoughalldigitalcomputersaresimilar,differentsizecomputersworkondifferentspeeds

andshowdifferentfunctionsaswellasacceptdifferenttasksrequiredbypeople.Ingeneral

speaking,thelargeristhecomputersize,thefasterisitsspeedandthemorepowerfulisitsfunction.

Forexamples,playinggamesorworkinginofficeonlyneedsaPC;tomonitorspaceshuttlelaunch

ortoforecasttheweatherrequiresalargeandpowerfulcomputer.Fromthispoint,Computerscan

beclassifiedintofourgroupsbytheirphysicalsizes.Thesmallestgeneral-purposecomputersare

calledmicrocomputersorPCs;thesmallcomputersystemsarenamedminicomputers;thelarge

computersaretermedmainframes;thelargestcomputershaveatitlesupercomputer.Thelargest

shouldbefastest,butitdoesnotmeanthatothersareslow.Thepropertiesandfunctionsof

computersnotonlydependontheirspeeds.

Thereareafewdevelopmentstagesinthehistoryofcomputers.Therefore,severalcomputer

generationsoccurinthehistory.

ThefirstelectronicdigitalcomputerwasborneinAmericain1946anditsbasicelementswere

vacuumtubes.Throughthe1950s,severalotherswerebuilt.Theywerethefirstgenerationof

computers,huge,heavy,expensiveandslow,poorlyreliable,onlyuseofmachinelanguageor

assemblelanguage,almostwithoutsoftwareconfiguration,merelyusedinscientificcomputation,as

wellasusingmuchmorepowerthantoday's,buttheystillmadegreatcontributionstocomputer

science,suchastheconceptsofstoredprograms,randomaccess.Theymadeabasicmodelof

modernelectroniccomputers.

4

Theinventionoftransistorsnotonlyproducedsmallportableradios,butalsoborethesecond

generationofcomputers,whichbecamesmall,light,lessexpensive,andbegantousesomehigh

programminglanguages,suchasBASIC,FORTRAN,ALOGOL,COBOL,etc.,andsoftware

configurationappeared,peripheralsincreasedmore,besidestheywereusedinscientificcalculation,

alsousedindataprocessandindustrialcontrol,butwerenotyetsmallandcheapenoughtoenter

families.

In1960s,integratedcircuitscame.Integratedcircuitsmeanthathugecomplicatedcircuitsand

millionsoftheirelementsareonlymadeonasmallsemiconductorchip,andtheyusheredinthe

thirdgenerationofcomputers.Thecomputersinthirdgenerationmadegreatprogressincomputer

scienceinallways.Theoperatingsystemscameout,thecommercialcomputersbegantobe

standardized,modularized,categorizedandserialized,andfurthermore,theproblemsofsoftware

compatibilityweresolvedatthattime,therefore,computersenteredmanyotherapplicationand

researchdomains.TheirtypicalmodelswereTheSystem360lineofIBMcomputers.Specially,

large-scaleintegratedcircuitscreatedmiracles:computer'sspeedhasarrivedat400000Mzmore,

andthememoryspaceisover2G,hand-heldcomputerscanbesawinmanyoffices,digital

computersaresopopularthatmostmiddleclassfamiliescouldeasilyaffordthem.Itiswhyyoucan

seePCseverywhere.

Underthedevelopmentofscienceandtechnology,biologicalcomputersandquantum

computerswillemergeoutinnearfuture.Newgenerationsofcomputerswillbeborne.Theywillbe

thenewproductsofcombinationofelectronic,opticaltechnologies,superconductorandbionics.

Newproductscanprocessknowledge,automaticallyeditandtestprograms,correcterrors,andcan

proceedtoenterandoutputnaturallanguages,graphs,soundsandcharacters.Newtechnologieswill

makecomputersystemconstructionandmodelbereformed,forexamples,data-flowcomputersand

nerve-networkcomputershavebeensuggested.

NEWWORDS

viewpoint观点

spaceshuttle航天飞机

versatility多样性

digitalcomputer数字计算机

analogcomputer模拟计算机

standardized标准化

modularized模块化

Categorizedandserialized系列化

superconductor超导体

bionics仿生学

mainframe大型机

feature特征

concept概念

5

classify分类

vacuumtube真空管

transistor晶体管

integratedcircuit集成电路

generation代

biological生物的

quantum量子

technology技术

emerge浮现

EXERCISE

1.TranslatethefollowingintoEnglish.

⑴计算机可分成模拟计算机和数字计算机两种。

⑵计算机越大，能干的事情越多。

⑶科学和技术是发展计算机的动力。

(4)集成电路标志着第三代计算机的问世。

⑸计算机的模式也可改革。

(6)光电技术的结合创造奇迹。

2.AnswerthefollowingquestionsinEnglish.

(1)Howtoassessthepropertiesandfunctionsofacomputer?

(2)Howtoclassifythegenerationsofcomputers?

(3)Incomputermarket,theysaythatthefourthgenerationcomputersexist.Isthejudgment

correct?Why?

(4)Couldyoutellthefutureofcomputers?

3.Writeabriefsummaryofin50words.

READINGMATERIAL

SUPERCOMPUTER

IBMhasinkedadealtoprovidewhatitsayswillbeoneofthe10largestsupercomputers.

TheArmonkN.Y.,companyannouncedFridaythatitwillbuildasupercomputercapableof

4.24trillioncalculationspersecondfbrtheKoreaInstituteofScience,TechnologyandInformation.

Supercomputersarethefastestclassofcomputers,generallytyinghundredsofprocessors

togethertotacklemathematics-intensivetaskssuchasweatherforecastingandgeneticsresearch.

Undertheagreement,worth$27million,IBMwillbegininstallingthemachinelateintheyear

andfinishearlyin2003.ThemachinebasedonIBM'sforthcomingPower4processorwillbeused

bytheinstitutestostudyphysics,chemistryandfluidmechanics,andotherthings.

6

IBMisthedominantsupercomputermaker,anditsASCIWhitenuclearweaponssimulation

machinetopsthelistoftheworld'sfastest.Thecompanyoflatehasbegunsigningcontractsto

deliversupercomputersthatusePower4.

German/sMaxPlanckSocietyfortheAdvancementoftheSciencesannouncedinMaythatit

wouldinstallaPower4supercomputer,designedtoperformupto3.8trillioncalculationsper

second.TheMunich,Germany-basedsocietywilluseittoresearchastrophysicsandbiochemistry,

amongotherthings.IBMexpectstocompletethemachinein2002.

ThePower4combinesvariousIBMchip-makingtrickswithtwo1GHzorfasterprocessor

coresinthesamechip,effectivelydoublingprocessorpower.Thechipisduelaterthisyear.IBM

willalsoofferthechipinits32-processorRegattaservers,thisfall.

TheFinnishMinistryofEducationalsohaspurchasedaPower4-basedsupercomputer,anIBM

representativesaid.

7

1.3COMPUTERCODES

Computersonlyunderstandandstoreonelanguage-machinelanguage,whichiscomposedof

stringsofbinarydigitsIsandOs.Aninstructionconsistsofdigits,characters,orsymbols.A

programismadeupofnumbers,characters,andinstructions.Howcannumbers,lettersandsymbols

berepresentedbystringsofIsandOs?Thesophisticatedwayshouldbelearntalittle.

Anynumbers,lettersorsymbolsstoredincomputersneedcodedformsdespitetheir

differences.Onlyincertainforms,thecomputerscanreallyunderstandthem.Howarethey

encoded?Thepopularwayisthebinarycodeddecimal(BCD)approach.Theapproachcan

convertadecimalnumberintoitsbinaryequivalentbutnotintoapurebinaryform.Weshowthe

BCDequivalentofsomesymbolsinFig.1.2.Toshow8and9needs4bits,soall10decimaldigits

arepresentedintheBCDby4bits.Now,wecanuseBCDtoexpressadecimalnumber:

389=001110001001or001110001001

decimalnumberBCDform

CharacterASCII

ZoneBitsNumericBits

100010Oil0000

200101Oil0001

300112Oil0010

81000A1000001

91001B1000010

Fig.1.2BCDformFig.1.3Selectedcharacters

4bitsBCDisagoodapproachbutcanonlyexpress16possibledifferentcharacters,itisnot

sufficientfbrtheuseonakeyboard.Thereare10decimaldigits,26lower-caseletters,26capital

lettersandtensofothercharactersaswellascontrolkeys,totallymorethan100keysonaPC

keyboardforinput.So,7or8bitsBCDcodesareintroduced.The7-bitAmericanStandardCode

fbrInformationInterchange(ASCII)iswidelyusedinPCanddatacommunication.Fig.1.3shows

youtheASCIIformatandthecodingusedtorepresentchosencharacters.Here,anASCIIcodeis

dividedintotwoparts:thezonebitpartandthenumericbitpart.Thezonebitparthasthreezone

bitspositions;thenumericbitpartcontains4numericbitpositions.Thezonebitpartindicatesthe

categoryofarepresentedcharacter,digit,letterorothersymbol;thelattermeanstheordinalnumber

orthebinaryequivalentofthecharacterordigitintherelatedcategory.Forexample,theASCII

codeof3isseparatedintotwoparts:Oiland0011.011iszonebitpartand0011isthebinary

equivalentof3.TheASCIIcodeofBis1000010.100isitszonebitpart,the0010isitsordinal

numberinEnglishlettercategory.Inamainframeorsupercomputersystem,8bitsBCDcodeis

accepted.

Becauseofdustparticlesonstoragemediaorimproperhumiditylevelsaroundthecomputer,

8

onebitinastringof7bitsmaybelostduringdatainput,processingoroutput.Anincorrect

charactercodeisproduced.Thedesignershavetofindamethodtodetectsucherrors.Themethod

isaddinganextracheckbitorparitybittothe7-bitcode.Soreally8bitsmaybestored.Seethe

following:

CharacterASCIIcodewithacheckbit

CheckbitZonebitsNumericbits

B01000010

Theprincipleofcheckorparityisthatthecomputersusethecheckbittoconfirmthatevery

validcharactercodeshouldalwayshaveanevennumberofbitIs.Thisiscalledaneven-parity

format.Butsomecomputersemployanodd-parityformat.

NEWWORDS

becomposedof由…组成

stringsof串

binarynumber二进制数

encode编码

berepresentedby由…代表

decimalnumber卜进制数

approach方法

convert...into把…转变成

zonebitposition标志位

numericbitposition数字位

category目录，类别

particle质点

improperhumiditylevel不合适的湿度

confirm确认

evenparity偶校验

format格式

EXERCISE

1.TranslatethefollowingintoEnglish.

⑴把一个二进制数变成十进制数。

⑵不适当的温度

⑶说明标志位的作用。

(4)检验错误

⑸确认有效

2.AnwerthefollowingquestionsinEnglish.

(1)Whatareabinarynumber?

(2)Whatareadecimalnumber?

9

(3)Whatdifferenceisbetweenanumberandadigit?

(4)WhatisBCDapproach?

(5)WhatisASCII?

3.WriteabriefcompositionofthetexttoshowmainideaofBCDapproachin50words.

10

CHAPTERSHARDWARE

2.1PROCESSOR

ThatCPUistheprocessorisrecognizedbymanyusers,andthejudgmentiscertainlyright.

Butfurthermore,CPUisonlyonesortofprocessors.TheyarenotalwaysmadefbrCPUs.Youcan

findmanyprocessorsinrefrigerators,air-conditionersandelevators,whicharenotCPUs.We

declarethatCPUequalsprocessorinthistextbook.ManymanufacturersalsocallthemCPUs

processors.Forexample,ifyoudetecttheinformationofyourPC,thePCmayshowyouthe

followinginformation.

Tab1e2.1HardwareInfoProgram

InfbBenchmarksTestSetupAboutQuit

SystemInformation

MainProcessorIntelCeleron,299.7MHz

MathCo-ProcessorInternal,299.7MHz

BusTypeISA+PCILocalBus(V2.10)+A.G.P.(VI.0)

MainboardModel:Unknown

MainboardChipsetVIAVT82C691ApolloPro

FirstLevelCacheInstruction16Kbytes,Data:16Kbytes

SecondLevelCacheOn-Chip:128Kbytes

SystemMemorySize640Kbytes

ExtendedMemorySize31,680Kbytes

Shadow+SpecialRAMSize448Kbytes

MachinetypeIBMPCAT

ComputerNameUnknown

BIOSManufacturerAwardModularBIOSV4.5IPG[10/27/98]

Theitem,MainProcessorintable2.1,meansamainbodyoftheCPU.

Theotheritemintable2.1willbelearnedinlatecontents.

TherearevarietiesofCPUsincomputermarkets.Aftermanyyearscompetition,threemain

CPUfamiliesoccupythecomputermarkets,theIntelseries,theAMDseriesandCyrixseriesshare

thecomputerworld..TheIntelPentiumseriesisbiggestone.

WhenyoubuyaPCoraCPU,youmustpayattentiontosomeindexesoftheCPU.

11

MainFrequencyorInternalFrequency

ThefrequencyistheworkingfrequencyoftheCPU,whichdeterminestheinternalworking

speedoftheCPU,thespeedofthesystem.ThefrequencycommonlyiscalledCPUspeedandfrom

133MHzto2GHz.

ExternalFrequency

ItisthesystembusworkingfrequencyandmanymanufacturerscallitCPUfrequency.Many

userscanseethewordFSB(FrontSideBus)inmanuals.FBSisthebusbetweenCPUandasetof

chips.TheworkingfrequencyofthebusiscalledFBSfrequencywhichisactuallyisexternal

frequency.

CPURatio

Theratioistheproportionofinternalfrequencytoexternalfrequency.Itissaidthatratio=

internalfrequency/externalfrequencyorCPUspeed/CPUfrequency.Theratiosareoften2.0,2.5,

3.0,3.5~8.0,8.5,9.0,9.5,etc.Theratiocanbechangedwithjumpertechno