基于新信息技术的计算机英语（第二版）课件 Unit 2 Computer Hardware

Section1SituationalDialogue

Section2ReadingMaterial

Section3ExtendedReadingSection1SituationalDialogueTeensandComputersTodd:OK,Jeanna,youlikethecomputer!Jeanna:Yes,Ido.Todd:OK.Tellusaboutcomputers.Jeanna:Well,IgoonthecomputeralotandItalkwithfriendsthroughAOLinstantmessenger.AndIjustmovedfrommyhometowntoSacremento,soit'sagoodwaytokeepintouchwitholdfriends.Todd:Yeah.Doyoulearnaboutcomputersatschooloronyourown?Jeanna:IpickedmostofwhatIknow,I'vepickeditup,through,yaknow,theyears,andsomeatschool,likekeyboardingandsuch.Todd:OK.DoyouhavealaptoporaPC?Jeanna:IhaveaPC.ACompac.Todd:Doyoulikeyourcomputerordoyouwantanewone?Jeanna:IwantanewonecauseIthinkIscrewedmineupandit'salittlebitslownow.Todd:OK.Howlonghaveyouhadyourcomputer?Jeanna:I'vehaditforabout3or4years.Todd:Oh,yeah,that'sprettyoldforacomputer.Yeah,sodoyoutalktoyourfriends?Jeanna:Yeah,yesIdo.Todd:OK.Jeanna:Seegoingonandyouknowthegossip.Todd:Sonowadays,dohighschoolkidstalkbye-mailmorethancellularphone?Jeanna:Mostpeopletalkbyeithere-mailorcellularphone.Youknowalotofpeopledon'tusetheirhousephonesasmuch,andalotofpeoplehavecellularphones.Todd:OK.Thanksalot,Jeanna.Section2ReadingMaterialTheHardwareHardwarecanbecategorizedinnumerousways.Below,wewilllookatthecentralunit,orCentralProcessingUnit(CPU),andtheassociatedequipmentconsistingofauxiliarystorage,inputandoutputdevices.Alloftheunitsthatareconnectedtothecentralprocessingunitarecalledperipheraldevices.Inthissectionwewillconsidereachcomponentinturn.CPUThepartofthecomputersystemthatperformsthelogictransformationsonthedataandcontrolsalltheotherdevicesisthecentralprocessingunit,orCPU.TheCPUinterpretsandexecutestheprograminstructions.Ithasthreemaincomponents:theArithmetic-LogicUnit(ALU),thecontrolunit,andtheprimarystorageunit.Inmanypersonalcomputers,theALUandcontrolunitarefabricatedasasinglecomponentonasinglesiliconchipwiththeprimarystorageonseparatechips.Forthisreason,somepeoplerefertotheCPUasjusttheALUandcontrolunitandtreatprimarymemoryasaseparatedevice.Thecontrolunitservestocoordinateandcontroltheentireoperationofthecomputersystem.ItcontrolsthetransferofdatabetweentheCPU,primarystorage,andpossiblyotherauxiliarydevicesthatwillbediscussedlater.Thecontrolunitdecodesinstructionsandkeepstrackofwhichinstructionistobeexecutednext.Inamoderncomputingsystem,theremaybehundredsorthousandsofhardwarecomponents.Itisthefunctionofthecontrolunittocoordinatetheiractivities.AVideoDisplayTerminal(VDT)isusuallyemployedbytheusertomonitorthecomputer'sfunctionsandtosendcontrolcommandstotheCPU.Withlargesystems,thispersonwouldbearegularemployeecalledtheoperatorworkingataspecialVDTcalledaconsole.ThecontrolunitexamineseachinstructionandthenroutesthepropernumberstoALU.Thearithmetic-logicunitconsistsofthecircuitrythatperformsthespecifiedlogicalorarithmeticoperations.MemoryTheprimarystorageunit,ormainmemory,storesalldataandinstructionsthataredataandinstructionsbeforetheycantobeusedbytheCPU.MainmemoryisdividedintoalargenumberofstoragelocationsusedbytheCPU.Afixedsizeofstoragelocationsiscalledword.Eachwordcanbeaccessedbythecontrolunitbecauseithasauniqueaddress.Theword'saddressisjustlikeyourpostaladdressexceptitisasingleuniquenumber.Eachwordismadeupofafixednumberofunitscalledbytes.Inmostsystems,abytecanholdonecharacterofdata.Oftenthehardwarelogicpermitsaccesstoindividualbytesanditappearstotheuserthatthecomputeris“byteaddressable,”when,infact,afullwordhasbeenaccessedinmemory.Thesizeofacomputer'smemoryisusuallyexpressedintermsofbytes.Themetricabbreviationsforonethousand(K),onemillion(M)andonebillion(G),areusedinspecifyingmemorysize.Theseactuallystandforkilobyte,megabyteandgigabyterespectively.However,becauseofthebinarynatureoftoday'scomputers,itisusualtohaveKas210(or1,024),Mas220(or1,048,576)andGas230(or1,073,741,824).Therefore,a128Mcomputerhasapproximately128,000,000bytes,orcharacters,ofmemory.Thesizeofthememoryisoneoftheparametersthatdeterminesthepowerandcostofthecomputer.AuxiliarystoragedevicesIntoday'smoderncomputingsystems,itisnecessarytohaveanotherformofmemory.Itisoftenthecasethatthemainmemoryisnotlargeenoughtoaccommodateallthedatanecessaryforaparticularapplication.Itisalsothecasethatmainmemoryisonlyusedtoholddatathatarecurrentlybeingprocessed.Whennotinuse,dataarestoredonauxiliarystoragedevices.Auxiliarystoragedevices(sometimescalledsecondarystorage)canovercomethisdifficulty.Themostcommondevicesusedaremagneticdiskdrives,CDsormagnetictapesusedforbackups.Manypersonalcomputersstilluseaflexiblediskcalledafloppy.CommonmemorysizesforpersonalcomputersareintheorderofseveraltenthsofM,whileassociatedharddiskdrivesmaycontaintenthsofgigabytesofstorage.Auxiliarystoragedevicescanstoreverylargequantitiesofdatainaneconomicalandreliablemanner.TheirmajorlimitationisthatthedataarenotavailabletotheCPUnearlyasquicklyasaredatastoredinmainmemory,andcaremustbetakentobalancetheuseofmainandauxiliarymemory.Mainmemorymaybeupto100,000fasterthanauxiliarymemory.Input/OutputdevicesInformationwenormallydealwithinourdailylives,suchasprintedmaterialwereadorvoiceinformationwehearonthetelephone,isessentiallyuselesstothecomputerintheformthatweunderstand.Devicesthatconvertdataintoaformthatthecomputercaninterpret(computer-readable)andenteritintothecomputerarecalledinputdevices.Thereisawidevarietyofinputdevices.Amongtheoneswewillconsiderarekeyboarddevices,scanningdevices,andaudioorvoicerecognitiondevices.Asinotherareasofcomputing,technologicaladvancesininputdevicescontinuetoimproveaccuracyandspeedwhilereducingcosts.Outputdevicesservetwoimportantfunctions:·Tocreatenewcomputer-readablemediathatcanbeutilizedinsubsequentdataandinformationprocessingsteps.·Totransformtheinternalinformationintoaformthatwecanunderstand,suchasprintedreportsorvoicemessages.Somefamiliaroutputdevicesincludeprintersandplotters.TheMotherboardTheMotherboardservestoconnectallofthepartsofacomputertogether.TheCPU,memory,harddrives,andotherportsandexpansioncardsallconnecttothemotherboarddirectlyorviacables.Themotherboardisthepieceofcomputerhardwarethatcanbethoughtasthe“backbone”ofthePC,ormoreappropriatelyasthe“mother”thatholdsallthepiecestogether.Phones,tabletsandothersmalldeviceshavemotherboardstoo,butthey'reoftencalledlogicboardsinstead.Theircomponentsareusuallysoldereddirectlyontotheboardtosavespace,whichmeanstherearen'texpansionslotsforupgradeslikeyouseeindesktopcomputers.TheIBMPersonalComputerthatwasreleasedin1981isconsideredtobetheveryfirstcomputermotherboard(itwascalleda“planar”atthetime).PopularmotherboardmanufacturersincludeASUS,AOpen,Intel,ABIT,MSI,Gigabyte,andBiostar.MotherboardcomponentsEverythingbehindthecomputercaseisconnectedinsomewaytothemotherboardsothatallthepiecescancommunicatewitheachother.Thisincludesvideocards,soundcards,harddrives,opticaldrives,theCPU,RAMsticks,USBports,apowersupply,etc.Onthemotherboardarealsoexpansionslots,jumpers,capacitors,devicepoweranddataconnections,fans,heatsinks,andscrewholes.ImportantmotherboardfactsDesktopmotherboards,casesandpowersuppliesallcomeindifferentsizescalledformfactors.Allthreemustbecompatibletoworkproperlytogether.Motherboardsvarygreatlywithrespecttothetypesofcomponentstheysupport.Forexample,eachmotherboardsupportsasingletypeofCPUandashortlistofmemorytypes.Additionally,somevideocards,harddrives,andotherperipheralsmaynotbecompatible.Themotherboardmanufacturershouldprovideclearguidanceonthecompatibilityofcomponents.Inlaptopsandtablets,andincreasinglyevenindesktops,themotherboardoftenincorporatesthefunctionsofthevideocardandsoundcard.Thishelpskeepthesetypesofcomputerssmallinsize.However,italsopreventsthosebuilt-incomponentsfrombeingupgraded.Poorcoolingmechanismsinplaceforthemotherboardcandamagethehardwareattachedtoit.Thisiswhyhigh-performancedevicesliketheCPUandhigh-endvideocardsareusuallycooledwithheatsinks,andintegratedsensorsareoftenusedtodetectthetemperatureandcommunicatewiththeBIOSoroperatingsystemtoregularthefanspeed.Devicesconnectedtoamotherboardoftenneeddevicedriversmanuallyinstalledinordertomakethemworkwiththeoperatingsystem.PhysicaldescriptionofamotherboardInadesktop,themotherboardismountedinsidethecase,oppositethemosteasilyaccessibleside.Itissecurelyattachedviasmallscrewsthroughpre-drilledholes.Thefrontofthemotherboardcontainsportsthatalloftheinternalcomponentsconnectto.Asinglesocket/slothousestheCPU.Multipleslotsallowforoneormorememorymodulestobeattached.Otherportsresideonthemotherboard,andtheseallowtheharddriveandopticaldrive(andfloppydriveifpresent)toconnectviadatacables.Smallwiresfromthefrontofthecomputercaseconnecttothemotherboardallowthepower,reset,andLEDlightstofunction.Powerfromthepowersupplyisdeliveredtothemotherboardbytheuseofaspeciallydesignedport.Also,onthefrontofthemotherboard,thereareanumberofperipheralcardslots.Theseslotsarewheremostvideocards,soundcards,andotherexpansioncardsareconnectedtothemotherboard.Ontheleftsideofthemotherboard(thesidethatfacesthebackendofthedesktopcase)areanumberofports.Theseportsallowmostofthecomputer'sexternalperipheralstoconnect,suchasthemonitor,keyboard,mouse,speakers,networkcable,etc.AllmodernmotherboardsalsoincludeUSBports,andincreasinglyotherportslikeHDMIandFireWire,thatallowcompatibledevicestoconnecttoyourcomputerwhenyouneedthem—deviceslikedigitalcameras,printers,etc.Thedesktopmotherboardandcasearedesignedsothatwhenperipheralcardsareused,thesidesofthecardsfitjustoutsidethebackend,makingtheirportsavailableforuse.Section3ExtendedReadingHowBluetoothIsMakingOurLivesEasierWhenyouthinkofBluetoothtechnology,youmaybethinkingoftheBluetoothheadsetsusedtotakecallswhenyouaredrivingorsimplydon'twanttohavethephoneagainstyourear.ManypeoplearenowseeingBluetoothinawholedifferentlightandarenowusingittomakethingseasiertodothaneverbefore.Bluetoothhasbroadeneditshorizonsandfounditselfalmostindispensableinmanydifferentareasoftechnologytoday.HerearefiveexamplesofhowBluetoothtechnologyismakingourliveseasier.StreamingmusictoyoursoundsystemThereissomethingincrediblyconvenientaboutbeingabletorelaxinyourbed,streamingmusicfromyourmobiletoyoursoundsystemontheothersideoftheroom.Withthepossibilitiesthatservices,suchasSpotify,offerusinproducingone-of-a-kindplaylists,itisnoweasierthanevertoenjoymusicwithoutcompromise.Bluetoothjustaddstotheexperience,whichmeanswenolongerhavetogetoutofbedtochangetheCD.ThereareevenexternalBluetoothdevicesavailabletorevampoldtraditionalspeakers,givingthemtheabilitytoacceptBluetoothsignalslikemodernBluetooth-enabledspeakers.TrackingyoureverystepIfyouwanttotrackyourchild'severystep,Bluetoothstickersmeanthatyoucanseetheireverymovementinrealtimeonyoursmartphone.Althoughthisisnotforeveryone,itisprovedtobeusefulwhenyouhaveaccidentallylosttrackofyourchildinabusyplaceorhaveamissingpetthatmayjustbeinyournext-doorneighbor'sgarden.OpeningdoorsHaveyoueverclosedthefrontdoorbehindyourselfjustmomentslatertorealizeyouleftthekeysonthekitchentableandwon'tbeabletogetbackinafterwork?Ifyouareforgetfulwithyourkeys,thenyoumayfinditinterestingtoknowthatyoucanuseaBluetooth-drivensmartphoneapptounlockdoorswithoutyourkeys.Thisisprettyusefulifyoucan'taffordtogetanewlockfittedandasetofnewkeys.Ifyoudon'twanttoleavethecar,youcanalsousetheapptoopenyourgaragedoorwhenitisraining.WirelessgamingTetheredgaminghandsetswererestrictingandmeantthatthereisalimitofhowfaryoucouldsitfromthegamingconsole.PS3andNintendoWiiarestrongadvocatesofwirelessgaming,allowingtheiruserstohaveamorerealisticgamingexperience.Astelevisionshavegotbigger,ithasbecomemoreimportanttositfurtherawayfromthescreen,withoutpullingthegamesconsoleofftheshelf.DrivingmusicJustaswealllovetheconvenienceofbeingabletostreammusicfromourbedtoourbedroomsoundsystem,thesameprincipleappliestocarsoundsystems.Whenyouaredrivingandwantmorechoicethanyourcollectionof3CDsfromyearsagoortheradio,itcanbeveryconvenienttostreamallofyourfavoritemusicfromyoursmartphonetoyourcar'ssoundsystem.ThereareonlyfivewaysinwhichBluetoothtechnologyismakingoureverydayliveseasierarelistedabove,buttherearemanymoreways.OneofthemainareasweareseeingBluetoothbeingusedtogreateffectisthehealthandfitnessindustry,withawiderangeofgadgetstomonitorouractivity.WiththetechnologysurroundingBluetoothmodulescontinuouslyevolving,whoknowswhatBluetoothwillofferusintenyears'time.AlibabaGroupWillInvest$15BintoaNewGlobal

ResearchandDevelopmentProgramAlibabaGroupannouncedtodaythatitplanstoinvestmorethan$15billionoverthenextthreeyearsintoaglobalresearchanddevelopmentinitiativecalledAlibabaDAMOAcademy.TheChinesetechgiantsaidtheprogram,whichiscurrentlyrecruiting100researchers,willhelpitreachitsgoalofservingtwobillioncustomersandcreating100millionjobsby2036,whilealso“increasingtechnologicalcollaborationworldwide”.DAMOAcademy(theinitialsstandfor“discovery,adventure,momentumandoutlook”)willbeledbyAlibabaGroupchieftechnologyofficerJeffZhangandstartbyopeninglabsinsevencitiesaroundtheworld:BeijingandHangzhouinChina;SanMateoandBellevueintheU.S.;Moscow,Russia;TelAviv,Israel;andSingapore.Alibaba’sresearcherswillcollaboratecloselywithuniversityprogramssuchasU.C.Berkeley’sRISELab,whichisdevelopingtechnologiesthatenablecomputerstomakesecuredecisionsbasedonreal-timedata.DAMOAcademy’scurrentadvisoryboardalsoincludesprofessorsfromPrinceton,Harvard,MIT,theUniversityofWashington,ColumbiaUniversity,BeijingInstituteofTechnology,PekingUniversityandZhejiangUniversity.Researchwillfocusonawidearrayofareas,includingdataintelligence,theInternetofThings,financialtech,quantumcomputingandhuman-machineinteraction.Morespecifically,AlibabaGroupsaidresearcherswilllookatmachinelearning,networksecurity,visualcomputingandnaturallanguageprocessing.AlibabajoinsothermajorChinesetechfirmsinsettinguplabsandworkingcloselywithtechnologyresearchersanduniversitiesintheU.S.andothercountries.TheseprogramsgivecompaniesthebenefitofdippingintonewtalentpoolswithouthavingtoconvincepotentialhirestomovetoChina(andalsopotentiallyluringthemawayfromrivalslikeAmazon,Facebook,GoogleandApple).Forexample,Baidu’sresearchlabinSiliconValley,whichworksonbigdata,deeplearningandartificialintelligence,isrecruitingfromtopAmericanresearchuniversities,whileTencent(themakerofWeChat)announcedplansinMaytosetupanAIresearchlabinSeattle.HuaweialsosetupanAIresearchpartnershipwithU.C.Berkeleylastyearwithinitialfundingof$1million.10WaystoMakeaComputerMoveFasterThelongeracomputerisinuse,thesloweritgets.Evenifyouhavetakenexcellentcareofit,youcannotentirelysafeguarditagainstslowingdown.However,therearequiteafewwaystoimproveitsqualityoflifebymakingitmovefaster.CleanoutsomejunkYoucanclearoutunnecessarydatastoredinyourcomputerbyremovingthecacheandcookiesinyourbrowser.IfyouuseInternetExplorer,goto“Tools”andclickonthe“InternetOptions”,thenchoosetodelete“BrowserHistory”.InMozillaFirefox,clickon“Tools”andthenclickon“ClearRecentHistory”.DefragmentUsecausesharddrivedatatoscatter.Thisdiskfragmentationwillmakeyourcomputerslowerorevencrash.RuntheWindowsDiskDefragmenterutilitytoputallthepiecesbacktogetheronyourharddriveandmakefileaccessmoreefficient.IntheStartmenu,choose“Run...”,andtype“defrag”toaccesstheapplet.VirusscanAlthoughsometimesavirusdoesnotcompletelydestroyyourcomputer,itcanmakethecomputerslow.Pleaseinstallanantivirusprogramandrunscansfrequently.Adware/SpywarescanMalici