FPGA片上系统SOC设计1

FPGA片上系统SOC设计2009.09.12课程内容介绍FPGA的起源及发展FPGA结构比较FPGA配置FPGA厂商及设计工具FPGA与ASIC设计风格基于示意图和硬件描述语言（HDL）的设计VerilogHDL基础VerilogHDL设计基于嵌入式处理器的设计实验参考资料TheDesignWarrior’sGuidetoFPGAs（英文原版）FPGA设计指南：器件、工具和流程（中文译版）台湾清华VerilogHDL教程Xilinx公司文档IntroductionWhatareFPGAs?WhyareFPGAsofinterest?WhatcanFPGAsbeusedfor?WhatareFPGAs?Fieldprogrammablegatearrays(FPGAs)aredigitalintegratedcircuits(ICs)thatcontainconfigurableblocksoflogicalongwithconfigurableinterconnectsbetweentheseblocks.SomeFPGAsmayonlybeprogrammedasingle(OTP),whileothersmaybereprogrammedoverandoveragain.Itsprogrammingtakesplace“inthefield”.ThismaymeanthatFPGAsareconfiguredinthelaboratory,oritmayrefertomodifyingthefunctionofadeviceresidentinanelectronicsystemthathasalreadybeendeployedintheoutsideworld.Ifadeviceiscapableofbeingprogrammedwhileremainingresidentinahigher-levelsystem,itisreferredtoasbeingin-systemprogrammable(ISP).IntroductionWhatareFPGAs?WhyareFPGAsofinterest?WhatcanFPGAsbeusedfor?WhyareFPGAsofinterest?TherearemanydifferenttypesofdigitalICs.Ofparticularinteresttoushere,however,areprogrammablelogicdevices(PLDs,includingbothSPLDsandCPLDs),application-specificintegratedcircuits(ASICs),application-specificstandardparts(ASSPs),and-ofcourse-FPGAs.PLDsaredeviceswhoseinternalarchitectureispredeterminedbythemanufacturer,butwhicharecreatedinsuchawaythattheycanbeconfigured(programmed)byengineersinthefieldtoperformavarietyofdifferentfunctions.IncomparisontoanFPGA,however,thesedevicescontainarelativelylimitednumberoflogicgates,andthefunctionstheycanbeusedtoimplementaremuchsmallerandsimpler.ASICsandASSPs,cancontainhundredsofmillionsoflogicgatesandcanbeusedtocreateincrediblylargeandcomplexfunctions.Theyarebasedonthesamedesignprocessesandmanufacturingtechnologies.Botharecustom-designedtoaddressaspecificapplication,theonlydifferencebeingthatanASICisdesignedandbuilttoorderforusebyaspecificcompany,whileanASSPismarketedtomultiplecustomers.WhyareFPGAsofinterest?AlthoughASICsoffertheultimateinsize,complexity,andperformance;designingandbuildingoneisanextremelytime-consumingandexpensiveprocess,withtheaddeddisadvantagethatthefinaldesignis“frozeninsilicon”andcannotbemodified.Thus,FPGAsoccupyamiddlegroundbetweenPLDsandASICsbecausetheirfunctionalitycanbecustomizedinthefieldlikePLDs,buttheycancontainmillionsoflogicgatesandbeusedtoimplementextremelylargeandcomplexfunctionsthatpreviouslycouldberealizedonlyusingASICs.ThecostofanFPGAdesignismuchlowerthanthatofanASIC.Atthesametime,implementingdesignchangesismucheasierinFPGAs,andthetime-to-marketforsuchdesignsismuchfaster.IntroductionWhatareFPGAs?WhyareFPGAsofinterest?WhatcanFPGAsbeusedfor?WhatcanFPGAsbeusedfor?Inthemid-1980s:gluelogic,mediumcomplexitystatemachines,andrelativelylimiteddataprocessingtasks.Duringtheearly1990s:telecommunicationsandnetworkingarenas,bothofwhichinvolvedprocessinglargeblocksofdata.Towardtheendofthe1990s:theuseofFPGAsinconsumer,automotive,andindustrialapplicationsunderwentahumongousgrowthspurt.Bytheearly-2000s,high-performanceFPGAscontainingmillionsofgateshadbecomeavailable.Someofthesedevicesfeatureembeddedmicroprocessorcores,high-speedinput/output(I/O)interfaces,andthelike.Theendresultisthattoday’sFPGAscanbeusedtoimplementjustaboutanything.WhatcanFPGAsbeusedfor?ASICandcustomsilicon:Today’sFPGAsareincreasinglybeingusedtoimplementavarietyofdesignsthatcouldpreviouslyhavebeenrealizedusingonlyASICsandcustomsilicon.Digitalsignalprocessing:Today’sFPGAscancontainembeddedmultipliers,dedicatedarithmeticrouting,andlargeamountsofon-chipRAM,allofwhichfacilitateDSPoperations.WhenthesefeaturesarecoupledwiththemassiveparallelismprovidedbyFPGAs,theresultistooutperformthefastestDSPchipsbyafactorof500ormore.Embeddedmicrocontrollers:Theselowcostdevicescontainon-chipprogramandinstructionmemories,timers,andI/Operipheralswrappedaroundaprocessorcore.FPGApricesarefalling,however,andeventhesmallestdevicesnowhavemorethanenoughcapabilitytoimplementasoftprocessorcorecombinedwithaselectionofcustomI/Ofunctions.WhatcanFPGAsbeusedfor?Physicallayercommunications:Thefactthattoday’shigh-endFPGAscancontainmultiplehigh-speedtransceiversmeansthatcommunicationsandnetworkingfunctionscanbeconsolidatedintoasingledevice.Reconfigurablecomputing:ThisreferstoexploitingtheinherentparallelismandreconfigurabilityprovidedbyFPGAsto“hardwareaccelerate”softwarealgorithms.FundamentalConceptsThekeythingaboutFPGAsAsimpleprogrammablefunctionFusiblelinktechnologiesAntifusetechnologiesMask-programmeddevicesPROMsEPROM-basedtechnologiesEEPROM-basedtechnologiesFLASH-basedtechnologiesSRAM-basedtechnologiesThekeythingaboutFPGAsThethingthatreallydistinguishesanFPGAfromanASICis…thecrucialaspectthatresidesatthecoreoftheirreasonforbeingis…embodiedintheirname:Thepointisthatinordertobeprogrammable,weneedsomemechanismthatallowsustoconfigure(program)aprebuiltsiliconchip.FundamentalConceptsThekeythingaboutFPGAsAsimpleprogrammablefunctionFusiblelinktechnologiesAntifusetechnologiesMask-programmeddevicesPROMsEPROM-basedtechnologies