基于单片机的脉冲频率测量系统的设计

基于单片机的脉冲频率测量系统的设计院系：机电与自动化学院专业班：电气自动化技术1001班姓名：学号：20102822025指导教师：2013年5月基于单片机的脉冲频率测量系统的设计Pulsefrequencymeasurementsystembasedonsingle-chipdesignI摘要在电子领域内,频率是一种最基本的参数,并与其他许多电参量的测量方案和测量结果都有着十分密切的关系。由于频率信号抗干扰能力强、易于传输，可以获得较高的测量精度。因此,频率的测量就显得尤为重要，测频方法的研究越来越受到重视。频率计作为测量仪器的一种，常称为电子计数器，它的基本功能是测量信号的频率和周期频率计的应用范围很广,它不仅应用于一般的简单仪器测量,而且还广泛应用于教学、科研、高精度仪器测量、工业控制等其它领域。随着微电子技术和计算机技术的迅速发展，特别是单片机的出现和发展，使传统的电子侧量仪器在原理、功能、精度及自动化水平等方面都发生了巨大的变化，形成一种完全突破传统概念的新一代侧量仪器。频率计广泛采用了高速集成电路和大规模集成电路，使仪器在小型化、耗电、可靠性等方面都发生了重大的变化。目前,市场上有各种多功能、高精度、高频率的数字频率计,但价格不菲。为适应实际工作的需要,本次设计给出了一种较小规模和单片机(AT89C51)相结合的频率计的设计方案,不但切实可行,而且体积小、设计简单、成本低、精度高、可测频带宽，大大降低了设计成本和实现复杂度。频率计的硬件电路是用Ptotues绘图软件绘制而成，软件部分的单片机控制程序，是以KeilC做为开发工具用汇编语言编写而成，而频率计的实现则是选用Ptotues仿真软件来进行模拟和测试。关键词：单片机AT89C51频率计汇编语言IIABSTRACTIntheelectronicfield,frequencyisakindofmostbasicparameter,andalltherearecloserelationsinthemeasurementschemesofmanyotherelectricparametersandresultofmeasuring.Becausethesignalanti-interferenceabilityoffrequencyisstrong,easytotransmit,canobtainhighermeasurementprecision.So,themeasurementoffrequencyseemsparticularlyimportant,theresearchofthemethodisbeingpaidattentionto.TheFrequencymeter,asonekindofthemeasuringinstrument,oftencalledtheelectroniccounter,itsbasicfunctionisthatfrequencyandapplicationofcycleFrequencymeterofmeasuringthesignalareinaverylargerange,itnotonlyappliestogeneralsimpleinstrumentmeasurementbutalsoapplytootherfieldssuchasteaching,scientificresearch,high-accuracyinstrumentmeasuring,industrialcontrolextensively.Withtherapiddevelopmentofmicroelectrictechniqueandcomputertechnology,especiallyappearanceanddevelopmentoftheone-chipcomputer,theinstrumentshaveallchangedenormouslyinsuchaspectsasprinciple,function,precisionandautomaticleveltoenablethetraditionalelectronicsideamount,formakindofsideamountinstrumentofnewgenerationthattotallybrokethroughthetraditionalconcept.TheFrequencymeterhasadoptedthehigh-speedintegratedcircuitandlargescaleintegratedcircuitextensively,maketheinstrumentchangegreatlyinsuchaspectsasminiaturize,powerconsumptive,dependability.Atpresent,therearevariousdigitalFrequencymeterofmulti-function,highprecision,highfrequencyonthemarket,butthepriceishigh.Inordertomeettheneedoftherealwork,designandprovideonethistimeThedesignplanofFrequencymetercombiningwithone-chipcomputer(AT89C51)onasmallscale,notonlyfeasible,andsmall,designsimply,withlowcosts,theprecisionishigh,canexaminethebandwidthfrequently,havereducedthedesigncostandrealizedcomplexitygreatly.ThehardwarecircuitoftheFrequencymeterisdrawingwithPtotuesmappingsoftware,theone-chipcomputercontrolprocedureofthesoftwarepart,regardedKeilCasthedevelopinginstrumenttowriteinAssemblyLanguage,buttherealizationoftheIIIFrequencymeterwastoselecttocarryonimitatingandtestwithProtuesartificialsoftware.KeyWords：singlechipcomputerT89C51requencymeterAssemblyLanguageIV目录摘要.......................................................................................................................................IABSTRACT........................................................................................................................II绪论......................................................................................................................................11方案论证........................................................................................................................31.1数字频率计测量方法.................................................................................................31.2几种方案的优劣讨论.................................................................................................41.3本次设计采用的方案及选用依据.............................................................................52系统硬件设计................................................................................................................72.1数字频率计的工作原理.............................................................................................72.1.1一般数字式频率计的原理......................................................................................72.1.2基于单片机的数字频率计的原理..........................................................................72.2电路原理图及其主要硬件部分.................................................................................82.3放大整形电路.............................................................................................................82.4电源电路模块.............................................................................................................92.4.1电源电路的设计......................................................................................................92.5单片机.........................................................................................................................92.5.1AT89C51简介..........................................................................................................92.6显示电路...................................................................................................................132.6.1LED数码管工作原理..................................................................................