毕业设计论文 外文文献翻译 基于ARM的嵌入式系统的速成样机平台设计 中英文对照.docx

毕业设计论文 外文文献翻译 基于ARM的嵌入式系统的速成样机平台设计 中英文对照.docx

《毕业设计论文 外文文献翻译 基于ARM的嵌入式系统的速成样机平台设计 中英文对照.docx》由会员分享，可在线阅读，更多相关《毕业设计论文 外文文献翻译 基于ARM的嵌入式系统的速成样机平台设计 中英文对照.docx（18页珍藏版）》请在冰点文库上搜索。

TheDesignofaRapidPrototypePlatformforARMBased

EmbeddedSystem

G.P.HALKES,T.VANDAM.K.G.LANGENDOEN

Hardwareprototypeisavitalstepintheembeddedsystemdesign.Inthispaper,wediscussourdesignofafastprototypingplatformforARMbasedembeddedsystems,providingalow-costsolutiontomeettherequestofflexibilityandtestabilityinembeddedsystemprototypedevelopment.Italsoencouragesconcurrentdevelopmentofdifferentpartsofsystemhardwareaswellasmodulereusing.

ThoughthefastprototypingplatformisdesignedforARMbasedembeddedsystem,ourideaisgeneralandcanbeappliedtoembeddedsystemofothertypes.

LINTRODUCTION

Embeddedsystemsarefoundeverywhere,includingincellulartelephones,pagers,VCRs,camcorders,thermostats,curbsiderental-carcheck-indevices,automatedsupermarketStockers,computerizedinventorycontroldevices,digitalthermometers,telephoneansweringmachines,printers,portablevideogames,TVset-topboxes―thelistgoeson.Demandforembeddedsystemislarge,andisgrowingrapidly.

Inordertodelivercorrect-the-first-timeproductswithcomplexsystemrequirementsandtime-to-marketpressure,designverificationisvitalintheembeddedsystemdesignprocess.Apossiblechoiceforverificationistosimulatethesystembeingdesigned.Ifahigh-levelmodelforthesystemisused,simulationisfastbutmaynotbeaccurateenough,withalow-levelmodeltoomuchtimemayberequiredtoachievethedesiredlevelofconfidenceinthequalityoftheevaluation.Sincedebuggingofrealsystemshastotakeintoaccountthebehaviorofthetargetsystemaswellasitsenvironment,runtimeinformationisextremelyimportant.Therefore,staticanalysiswithsimulationmethodsistooslowandnotsufficient.Andsimulationcannotrevealdeepissuesinrealphysicalsystem.

Ahardwareprototypeisafaithfulrepresentationofthefinaldesign,guarantyingitsreal-timebehavior.Anditisalsothebasictooltofinddeepbugsinthehardware.Forthesereasons,ithasbecomeacrucialstepinthewholedesignflow.Traditionally,aprototypeisdesignedsimilarlytothetargetsystemwithalltheconnectionsfixedonthePCB（printedcircuitboards）.

Asembeddedsystemsaregettingmorecomplex,theneedsforthoroughtestingbecomeincreasinglyimportant.Advancesinsurface-mountpackagingandmultiple-layerPCBfabricationhaveresultedinsmallerboardsandmorecompactlayout,makingtraditionaltestmethods,e.g.,externaltestprobesand"bed-of-nails"testfixtures,hardertoimplement.Asaresult,acquiringsignalsonboards,whichisbeneficialtohardwaretestingandsoftwaredevelopment,becomesinfeasible,andtrackingbugsinprototypebecomesincreasinglydifficult.Thustheprototypedesignhastotakeaccountoftestability.However,simplyaddingsometestpointsisnotenough.Iferrorsontheprototypearedetected,suchasmisconnectionsofsignals,itcouldbeimpossibletocorrectthemonthemultiple-layerPCBboardwithallthecomponentsmounted.Allthesewouldleadtoanotherroundofprototypefabrication,makingdevelopmenttimeextendandcostincrease.

Besidestestability,itisimportanttomaintainhighflexibilityduringdevelopmentoftheprototypeasdesignspecificationchangesarecommon.Nowadayscomplexsystemsareoftennotbuiltfromscratchbutareassembledbyreusingpreviouslydesignedmodulesoroff-the-shelfcomponentssuchasprocessors,memoriesorperipheralcircuitryinordertocopewithmoreaggressivetime-to-marketconstraints.Followingthetop-downdesignmethodology,lotsofeffortinthedesignprocessisspentondecomposingthecustomers,requirementsintoproperfunctionalmodulesandinterfacingthemtocomposethetargetsystem.

SomepreviousresearchworkshavesuggestedthatFPLDs（fieldprogrammablelogicdevice）couldbeaddedtothefinaldesigntoprovideflexibilityasFPLDscanofferprogrammableinterconnectionsamongtheirpinsandmanymoreadvantages.However,extradevicesmayincreaseproductioncostandpowerdissipation,weakeningthemarketcompetitionpowerofthetargetsystem.Toaddresstheseproblems,therearealsosuggestionsthatFPLDscouldbeusedinhardwareprototypeasanintermediateapproachwhereasthiswouldstillbringmuchadditionalworktotheprototypedesign.Moreover,modulesontheprototypecannotbereuseddirectly.Inindustry,therehavebeencompaniesthatprovidecommercialsolutionsbasedonFPLDsforrapidprototyping[4].TheirproductsareaimedatSOC（systemonachip）functionalverificationinsteadofembeddedsystemdesignanddevelopment.

Inthispaper,wediscussourdesignofaRapidPrototypingPlatformforARMbasedEmbeddedSystem,providingalowcostsolutiontomeettherequestofflexibilityandtestabilityinembeddedsystemprototypedevelopment.Italsoencouragesconcurrentdevelopmentofdifferentpartsofsystemhardwareaswellasmodulereusing.Therestofthepaperisorganizedasfollows.Insection2,wediscussthedetailsofourrapidprototypingplatform.Section3showstheexperimentalresults,followedbyanoverallconclusioninsection4.

ILTHEDESIGNOFARAPIDPROTOTYPINGPLATFORM

A. Overview

ARMbasedembeddedprocessorsarewildlyusedinembeddedsystemsduetotheirlow-cost,low-powerconsumptionandhighperformance.AnARMbasedembeddedprocessorisahighlyintegratedSOCincludinganARMcorewithavarietyofdifferentsystemperipherals[5].Manyarmbasedembeddedprocessors,e.g.[6]-[8],adoptasimilararchitectureastheoneshowninFig.1.

Fig.1.Arm-basedembeddedprocessorblockdiagram

Theintegratedmemorycontrollerprovidesanexternalmemorybusinterfacesupportingvariousmemorychipsandvariousoperationmodes（synchronous,asynchronous,burstmodes）.Itisalsopossibletoconnectbus-extendedperipheralchipstothememorybus.Theon-chipperipheralsmayincludeinterruptcontroller,OStimer,UART,I2C,PWM,AC97,andetc.Someoftheseperipheralssignalsaremultiplexedwithgeneral-purposedigitalI/Opinstoprovideflexibilitytouserwhileotheron-chipperipherals,e.g.USBhost/client,mayhavededicatedperipheralsignalpins.Byconnectingorextendingthesepins,usermayusetheseonchipperipherals.Whentheon-chipperipheralscannotfulfilltherequirementofthetargetsystem,extraperipheralchipshavetobeextended.

ThearchitectureofanARMbasedembeddedsystemisshowninFig.2.Thewholesystemiscomposedofembeddedprocessor,memorydevices,andperipheraldevices.Toenablerapidprototyping,theplatformshouldbecapableofquicklyassemblingpartsofthesystemintoawholethroughflexibleinterconnection.OurbasicideaistoinsertareconfigurableinterconnectionmodulecomposedbyFPLDintothesystemtoprovideadjustableconnectionsbetweensignals,andtoprovidetestabilityaswell.Todeterminewheretoplacethismodule,wefirstanalyzethearchitectureofthesystem.

TheembeddedsystemshowninFig.2canbedividedintotwoparts.Oneistheminimalsystemcomposedoftheembeddedprocessorandmemorydevices.Theotherismadeupofperipheraldevicesextendeddirectlyfromon-chipperipheralinterfacesoftheembeddedprocessor,andspecificperipheralchipsandcircuitsextendedbythebus.

Theminimalsystemisthecoreoftheembeddedsystem,determiningitsprocessingcapacity.Theembeddedprocessorsarenowroutinelyavailableatclockspeedsofupto400MHz,andwillclimbstillfurther.Thespeedofthebusconnectingtheprocessorandthememorychipsisexceeding100MHz.Aspin-to-pinpropagationdelayofaFPLDisinthemagnitudeofafewnanoseconds,insertingsuchadevicewillgreatlyimpairthesystemperformance.

Theperipheralsenabletheembeddedsystemtocommunicateandinteractivewiththecircumstanceintherealworld.Ingeneral,peripheralcircuitsarehighlymodularizedandindependenttoeachother,andtherearehardlyneedsforflexibleconnectionsbetweenthem.

Hereweapplyareconfigurableinterconnectionmoduletosubstitutetheconnectionsbetweenmicrocomputerandtheperipherals,whichenablesflexibleadjustingofconnectionstofacilitateinterfacingextendedperipheralcircuitsandmodules.Asthespeedofthedatacommunicationbetweentheperipheralsandtheprocessorismuchslowerthanthatintheminimalsystem,theFPLDsolutionisfeasible.

Followingthisidea,wedesigntheRapidPrototypingPlatformasshowninFig.3.WedefinetheinterfaceICBbetweentheplatformandtheembeddedprocessorcoreboarthatholdstheminimalsystemofthetargetembeddedsystem.TheinterfaceIPBbetweentheplatformandperipheralboardsthatholdextendedperipheralcircuitsandmodulesisalsodefined.Theseenableustodevelopdifferentpartsofthetargetembeddedsystemconcurrentlyandtocomposethemintoaprototyperapidly,andencouragemodulereusingaswell.Thetwointerfacesareconnectedbyareconfigurableinterconnectmodule.Therearealsosomecommonlyusedperipheralmodules,e.g.RS232transceivermodule,busextendedEthernetmodule,AC97codec,PCMCIA/CompactFlashCardslot,andetc,ontheplatformwhichcanbeinterfacedthroughthereconfigurableinterconnectmoduletoexpeditetheembeddedsystemdevelopment.

B.ReconfigurableInterconnectModule

Withthefacilityofstate-of-artsFPLDs,wedesignareconfigureinterconnectionmoduletointerconnect,monitorandtestthebusandI/Osignalsbetweentheminimalsystemandperipherals.

Asthebusaccessingobeysspecificprotocolandhascontrolsignalstoidentifythedatadirection,theinterconnectionofthebuscanbeeasilyrealizedbydesigningacorrespondingbustransceiverintotheFPLD,whereastheinterconnectionoftheI/Osismorecomplex.AsI/Osar