摘要本系统是基于AT89C51单片机的数字式低频信号发生器。采用AT89C51单片机作为控制核心，外围采用数字/模拟转换电路（DAC0832）、运放电路（LM324）、按键和8位数码管等。通过按键控制可产生方波、三角波、正弦波等，同时用数码管指示其对应的频率。其设计简单、性能优好，可用于多种需要低频信号的场所，具有一定的实用性。各种各样的信号是通信领域的重要组成部分，其中正弦波、三角波和方波等是较为常见的信号。在科学研究及教学实验中常常需要这几种信号的发生装置。为了实验、研究方便，研制一种灵活适用、功能齐全、使用方便的信号源是十分必要的。本文介绍的是利用AT89C51单片机和数模转换器件DAC0832产生所需不同信号的低频信号源，其信号幅度和频率都是可以按要求控制的。文中简要介绍了DAC0832数模转换器的结构原理和使用方法，AT89C51的基础理论，以及与设计电路有关的各种芯片。文中着重介绍了如何利用单片机控制D/A转换器产生上述信号的硬件电路和软件编程。信号频率幅度也按要求可调。本次关于产生不同低频信号的信号源的设计方案，不仅在理论和实践上都能满足实验的要求，而且具有很强的可行性。该信号源的特点是：体积小、价格低廉、性能稳定、实现方便、功能齐全。关键词：AT89C51DAC0832LM3248位数码管显示AbstractWaveformThesystemisadigitalsignalgeneratorbasedonsinglechipcomputer.At89c51isusedasacontrolmicrocontrollercore.Thesystemiscomposedbydigital/analogcomversion(DAC0832),implycircuit,buttonandnixietube.Itcangeneratethesquare,triangleandsinewave,withnixietube.Thesystemcanbeusedforasignalsoureinthelow-frequencysignalsoure.Itisverypractical.Varioussignalsareanimportantpartofcorrespondentarea.Inthisarea,sinewave,trianglewaveandsquarewavearecommonsignals.Inscienceresearchandteachingexperiment,weoftenneedtheoccurrenceequipmentofthesesignals.Inordertomaketheexperimentandresearcheasier,todevelopasuitable,fullfunctionalandeasilyusedsignalssourceisessential.ThispaperintroducesthelowfrequencysourcesofdifferentsignalsthatareproducedbyAT89C51SCMandDAC0832.Itssignalrangeandfrequencycanbecontrolledbyrequirement.ThispaperbrieflyintroducesthestructureprincipleandusageofDAC0832,thebasictheoryofAT89C51andvariouschipswhichrelevanttodesigncircuit.thispaperemphasizedhowtouseSCMtocontrolthehardwarecircuitandsoftwareprogramofthesignalsabovewhichproducedbyDAC0832.Thesignalfrequencyrangealsocanbeadjustedbyrequirement.Thissignalsourcedesignplanconcernsonproducingdifferentlowfrequencysignals,notonlymeettherequestofexperimentintheoryandinpractice,butalsohavestrongfeasibility.Thetraitofthissignalsourceis:smallvolume,lowprice,stablefunction,easilyachievable,andfullfunction.Keywords:AT89C51,DA0832,LM324,8nixietubedisplay目录摘要...............................................................................IAbstract.....................................................................II目录............................................................................III前言..............................................................................11波形发生器概述......................................................21.1波形发生器的发展状况...................................21.2国内外波形发生器产品比较...........................42方案论证与比较......................................................52.1方案一...............................................................52.2方案二...............................................................62.3方案三...............................................................63硬件原理.......................................................
