函数信号发生器的研究与实现

？？？？？？本科生毕业论文(设计)正文题目：函数发生器的研究与实现学生姓名：？？？？学号：？？？？？？专业班级：？？？？？？？？？？指导教师：？？？？完成时间：？？？年4月20日摘要函数发生器主要作为实验用信号源，是现今各种电子电路实验设计应用中必不可少的仪器设备之一。本次设计的主要目的就是为了学习基于单片机的函数发生器的工作原理，设计出一个低频的函数发生器。从事本次设计不仅可以让我对函数发生器的原理有更深的了解，而且也对单片机的知识有更深的掌握。单片机有很多种类，而且制作函数发生器的方案繁多，本次设计是以AT89C51单片机为核心，选用DAC0832为数模转换芯片，并辅以必要的模拟电路，设计出了一个基于AT89C51单片机的函数信号发生器。其设计内容主要包括单片机最小系统的设计、DA转换模块的设计、键盘控制模块的设计及LCD显示模块的设计。其中DA转换模块包括2块DAC0832芯片和OP07运放电路，第一块DA芯片的输出作为第二块DA芯片的参考电压，而第一块DA芯片的2.5V参考电压由MC1403芯片的输出来提供；键盘控制模块采用3个按键来选择波形类型及调节频率、幅值；显示模块则采用LCD1602来显示波形类型、频率及幅值；最终将设计好的函数发生器的输出接上示波器，在示波器上显示实际输出的波形。本设计最终能达到预期的效果，能实现电压步进0.1V，方波能够任意调节占空比以及在LCD1602上显示波形类型、电压和频率，并且可以通过示波器来观察其输出的波形。关键词：AT89C51单片机DAC0832LCD1602按键ABSTRACTFunctionasthemaingeneratorsbysignals.Electroniccircuitsisnowthedesignintheapplicationofthenecessaryequipment.Thedesignofthemainpurposeistolearnrevivificationfunctionofthegeneratorsworks,alowfrequencyfunctionofthegenerators.inthisdesigncouldnotonlyallowmetotheprinciplefunctionsofprogramme，thereismore,butalsoforamoremonolithicintegratedcircuitstolearn.Monolithicintegratedcircuitstherearemanyvarieties,andtheproductionfunctionofthegenerators,thedesignisAT89c51monolithicintegratedcircuitstotheselectionofamoduledac0832thechips,andsupportedbythesimulationcircuits,anddevisedafunctionofthesignalbasedonat89c51monolithicintegratedcircuitsgenerators.Thedesignincludesmonolithicintegratedcircuitstothesystemdesign,andD/Athemoduleforthedesign,thekeyboardcontrolmoduleofthedesignandLCDmodulesdisplaydesign.OneofD/Athemodulesincludingtwodollarsandop07dac0832thedischargeoftheD/A,thechipistheD/AchipofthevoltageandthefirstpieceofD/Achips5vreferenceby2.thevoltagemc1403chipoftheoutputtoprovide;keyboardcontrolinthreekeytoselectthetypeandfrequency,waveofvaluedisplaysmodulelcd1602;isusedtoindicatethetypeandfrequencyandwavebe;Eventuallywillbedesignedtofunctionofthegeneratorsoutputmeetonoscilloscope,inthewaveisvariedinthepracticaloutput.Thedesignofthewilltoachievethedesiredresultscanbeachievedstep31vvoltageandwavestoanyregulationoffreeandlcd1602thanonthetypeofsignalwave,voltageandfrequency,andmay,bythewaveisvariedtoobservetheoutput.【Keywords】AT89C51MCUDAC0832LCD1602KEY目录第1章绪论..............................................................................................................................11.1课题背景........................................................................................................................................11.2设计要求及内容...........................................................................................................................21.2.1设计要求.............................................................................................................................21.2.2设计内容.............................................................................................................................21.3方案论证........................................................................................................................................21.3.1信号发生电路方案论证...................................................................................................21.3.2单片机的选择论证...............................................................................................31.3.3显示方案论证......................................................................................................31.3.4键盘方案论证.......................................................................................................3第2章单片机概述....................................................................................................................42.1单片机的发展历史及趋势........................................................................................................42.2AT89C51单片机结构简介.........................................................................................................52.2.1AT89C51的基本特性.......................................................................................................52.2.2AT89C51单片机的外部引脚介绍................................................................................6第3章系统硬件设计................................................................................................................83.1各模块硬件设计.............................................................................................................83.1.1系统总体设计.......................................................................................................83.1.2单片机最小系统设计...........................................................................................93.1.3位DA转换器DAC0832....................................................................................103.1.42.5V基准电压模块设计....................................................................................143.1.5系统显示功能设计.............................................................................................153.1.6系统按键功能设计.............................................................................................19第4章系统软件设计.................................................................................................