SSD2 Unit 3 and 4 Review Materials.docx
- 文档编号:7458572
- 上传时间:2023-01-24
- 格式:DOCX
- 页数:16
- 大小:124.37KB
SSD2 Unit 3 and 4 Review Materials.docx
《SSD2 Unit 3 and 4 Review Materials.docx》由会员分享,可在线阅读,更多相关《SSD2 Unit 3 and 4 Review Materials.docx(16页珍藏版)》请在冰豆网上搜索。
SSD2Unit3and4ReviewMaterials
1.BatchFileCreation
a.Namethefileoutput.bat
b.Thefileshouldreceiveasinputtwoparameters–acommandandafilename,andshouldredirecttheoutputofthecommandtothespecifiedfile:
outputcommandfilename
c.Theoutput.batbatchfileshoulderror-checktodetermineifafilebythenameoffilenamealreadyexists.
d.Ifafilebythenameoffilenamealreadyexists,thebatchfileshouldnotoverwritetheexistingfilebutreturnanerrormessagethatreads:
filenamealreadyexists.
Ans.Followingisthebatchfile:
@echooff
REMredirectstheoutputofacommandtoafile.
IFexist%2gotoERROR
IFnotexist%2gotoloop
:
ERROR
echo%2Alreadyexists.
gotoend
:
loop
%1>%2
gotoend
:
END
2.BatchFilesandMacros
a.WhatisaDOSbatchfile?
Ans.ADOSbatchfilecontainsasequenceofDOScommandsandnamesofprogramstoexecute.Thefilemayalsocontainflowcontrolcommandsthattellthecommandprocessortolooportohandleerrorconditionsinaparticularway.Itisaplaintextfilewithextension.BAT.Batchfileswereaddedtoeasetheworkrequiredforcertainregulartasksbyallowingtheusertosetupabatchscripttoautomatemanycommands.Whenabatchfileisrun,theshellprogramreadsthefileandexecutesitscommands,normallyline-by-line.Batchfilesareusefulforrunningasequenceofexecutablesautomaticallyandareoftenusedtoautomaterepetitiveortediousprocesses.
b.WhatisanExcelmacro?
Ans.AmacroinExcelisaseriesofExcelcommandsandfunctionsthatarestoredinaMicrosoftVisualBasicmoduleandcanberunwheneveryouneedtoperformthetask.
c.Whattypesoftaskscanabatchfileormacroperform?
Ans.Batchfileandmacroscanperformanytypeoftaskthatscriptandprogramwillsupport.
d.Whatarethebenefitsofusingbatchfilesandmacros?
Ans.Thebenefitsofusingbatchfilesandmacrosaretheabilitytoautomateroutinetasks.Tasksthatnormallyrequireseveralcommandsbutarealwayscompletedthesamewaycanbeautomated,sothatonecommandnowexecutestheentiresetofcommands,reducingmanhoursandincreasingproductivity.
e.Whatarethedrawbacksofusingbatchfilesandmacros?
Ans.Thedrawbacksofusingbatchfilesandmacrosisthattheyareautomatedandarenotalwaysabletohandleanomalousorerroneousdata.
3.BIOSandCMOS
a.ExplainthefunctionoftheBIOSROMinthebootprocess.
Ans.TheBIOSsoftwareisbuiltintothePC,andisthefirstcoderunbyaPCwhenpoweredon.TheprimaryfunctionoftheBIOSistosetupthehardwareandloadandstartanoperatingsystem.WhenthePCstartsup,thefirstjobfortheBIOSistoinitializeandidentifysystemdevicessuchasthevideodisplaycard,keyboardandmouse,harddiskdrives,opticaldiscdriveandotherhardware.TheBIOSthenlocatessoftwaregeldonaperipheraldevice,suchasaharddiskoraCD/DVD,andloadsandexecutesthatsoftware,givingitcontrolofthePC.Thisprocessisknownasbooting.
BIOSsoftwareisstoredonanon-volatileROMchipbuiltintothesystemonthemotherboard.TheBIOSsoftwareisspecificallydesignedtoworkwiththeparticulartypeofsysteminquestion,includinghavingknowledgeoftheworkingsofvariousdevicesthatmakeupthecomplementarychipsetofthesystem.Inmoderncomputersystems,theBIOSchip’scontentscanberewritten,allowingBIOSsoftwaretobeupgraded.
b.Defineflashing,withrespecttoBIOSROM.
Ans.InmodernPCstheBIOSisstoredinrewritablememory,allowingthecontentstobereplaced.Thisrewritingofthecontentsissometimestermedflashing.Thiscanbedonebyaspecialprogram,usuallyprovidedbythesystem’smanufacturer,oratPOST,withaBIOSimageinaharddriveorUSBflashdrive.Afilecontainingsuchcontentsistermed‘BIOSimage’.ABIOSmightbereflashedinordertoupgradetoanewerversiontofixbugsorprovideimprovedperformanceortosupportnewerhardware,orareflashingoperationmightbeneededtofixadamagedBIOS.ABIOSmayalsobeflashedbyputtingthefileontherootofaUSBdriveandbooting.
c.ExplainthefunctionofCMOSinthebootprocess.
Ans.TheCMOSbatteryholdsinformationofourBIOSinmemoryaswellaskeepingthesystemtime.ThebatterypowersourCMOSchip.WithoutthebatteryourPCwouldn’tstartup.ItretainstheBIOSinthememory,andifthebatterygoesflat,wewillgetabluescreensayingCMOScannotstartPC.Sowehavetochangethebattery.
d.WhatistheadvantageofhavinganunchangeableROMandachangeableCMOSduringthebootprocess?
Ans.ByhavingunchangeableBIOSadefaultstartupconfigurationisalwayspossible.Sincehoweverthestartupconfigurationmaydifferfrommachinetomachine,thechangeableCMOSallowsusertospecifyexactlyhowthebootwilloccurontheirmachine,possiblychangingthestartupfromthedefault.
e.ConsiderthattheCMOShaslostpower.
i.WhathappenstothedatathatwasstoredinCMOS?
Ans.CMOSisvolatileanditlosesalldata.
ii.HowdoestheCMOSlosingpoweraffectthebootprocess?
Ans.WhenCMOSpowerfailsitnolongercontainsconfigurationdataandthereforewhenamachineisbooteditwillusethedefaultsettingscontainedintheBIOS.
f.ListtwowaystochangetheinformationintheCMOS.
Ans.
1.WindowsPlugnPlay.
2.BIOSsetupandconfigurationutility.
4.BootProcess
a.Whataretwofunctionsofthebootprocess?
Ans.Thebootprocessensuresthatcrucialcomponentsofthecomputersystemsuchasthememory,screendisplayetcisfunctional.Italsoloadstheoperatingsystemfromtheharddiskintomemorytoenablethecomputertobeoperational.
b.DescribethestepsinvolvedinaPOST.
Ans.WhenpowerisappliedtothesystemandtheBIOSbeginstoexecute,theBIOSinitiatesthePOSTsequence:
-Firstitenablesthevideocardanddisplayssomebasicinformationlikethetypeofvideocardinstalled,thenameoftheBIOSmanufacturer,andtheBIOSversionnumber.
-ItthendeterminestheamountofDRAMinstalledinthesystem,anditmayperformamemorytest.
-Then,itdetermineswhatexpansioncardsandadaptersarepresentandtheBIOSinitializesthosecardsandadapters.
-AttheconclusionofPOSTsequence,theBIOSdisplayssystemconfigurationinformation,suchasthetypeofprocessorinstalled,cachememoryinformation,thetypesofeachofthediskdrivesitfound,theaddressesofanyserialandparallelports,andalistofotherexpansioncardsitdetected.
OncethePOSTsequenceiscompleted,thenextjoboftheBIOSistoloadinaprogramthatwillinturnloadtheoperatingsystem.BIOS,thenreadsMasterBootRecord,whichthenloadsintheOSandstartsitrunning.
c.Fillinthefollowingchartbyarrangingthestepsofthebootprocessbelowinorder.
-Stepsinthebootprocess:
PowerOn
CopyBIOStoRAM
ExecuteBIOSprogram
POST
Identifyperipheraldevices
SearchforMBRandloadtheOS.
Loaddevicedrivers.
Operatingsystemfunctional.
d.Explainwhatthetermsearchordermeansinrelationtothechartinpartc.
Ans.SearchorderistheorderinwhichMBRissearchedfor.ThisorderbeginsbylookingindriveA,whichisnormallyafloppydrive.Ifthereisnodiskinthatdrive,orifthediskdoesnotcontainaMBR,thenitlooksinthedriveB,ifoneexists.Ifunsuccessfulthere,itmovestothedriveC,whichisnormallythemainharddiskdrive,andlooksforaMBRthere,andsoon.
e.Explainwhatthetermbootstraploadermeansinrelationtothechartinpartc.
Ans.AbootstraploaderisaprogramthatresidesinthecomputersEPROM,ROM,orothernon-volatilememorythatisautomaticallyexecutedbytheprocessorwhenthecomputerturnedon.Thebootstraploaderreadstheharddiskdrivesbootsectortocontinuetheprocessofloadingthecomputer’soperatingsystem.
5.Databases
a.Whatimportant,basicfunctiondoalldatabasesserve?
Ans.Theimportantfunctionsadatabaseservesare:
-Reduceddataredundancy
-Reducedupdatingerrorsandincreasedconsistency
-Greaterdataintegrityandindependencefromapplicationsprograms
-Improveddataaccesstousersthroughuseofhostandquerylanguages
-Improveddatasecurity
-Reduceddataentry,storageandretrievalcosts
-Facilitateddevelopmentofnewapplicationsprogram
b.Explaintheuseofrecordsandfieldswithinadatabse.
Ans.Fieldisthesmallestunitofmeaningfuldataandformsthebasicbuildingblockofadatafilewhereasrecordisacollectionoffieldsofdataaboutanentity.
c.Whatisprimarykey,andhowisitused?
Ans.Theprimarykeyofarelationaltableuniquelyidentifieseachrecordinthetable.Primarykeysmayconsistofasingleattributeormultipleattributesincombination.
d.Inrelationtoadatabase,whatfunctiondoesSQLserve?
Ans.SQLisadatamanipulationlanguagethatallowsuserstoenterandretrievedatafromthedatabase.
e.Listthreeexamplesofdatabasesthatyoucaninteractwithontheinternet.
Ans.Examplesofdatabasesthatyoucaninteractwithontheinternetare:
,shutterstock.co.in
6.Interrupts
a.Definehardwareinterrupt.
Ans.HardwareinterruptisatimedependentsystemalertthatsignifiesthatanI/Ocomponentneedsattention.
b.Giventhatthesystemiscurrentlyrunningaprocess,listthestepsthesystemperformstoprocessaninterruptandreturntotheoriginalprocess.
Ans.SystemstopsprocessingthecurrenttaskandcopiesittoRAM.
SystemcopiestheinterruptrequestfromRAMtotheregistersandbeginprocessingnewinstructions.
Systemfinishestheinterruptandcopiesoriginalprocessbacktotheregisters.
Systemexecutesoriginalprocessuntilfinish.
c.Whatcausesaninterrupt?
Ans.An
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- SSD2 Unit and Review Materials