基于单片机的简易计时器设计

南华大学电气工程学院课程设计i摘要：单片机自70年代问世以来得到蓬勃发展，目前单片机功能正日渐完善：单片机集成越来越多资源，内部储存资源日益丰富，用户不需要扩充资源就可以完成项目开发，不仅是开发简单，产品小巧美观，同时抗干扰能力强，系统也更加稳定，使它更适合工业控制领域，具有更广阔的市场前景；提供在线编程能力，加速了产品的开发进程，为企业产品上市赢得了宝贵时间。本设计通过STC89C51单片机以及单片机最小系统和三极管驱动以及外围的按键和数码管显示等部件，设计一个基于单片机的简易计时器。设计通过四位一体共阳极数码管显示，并能通过按键对秒进行设置。关键词：STC89C51单片机，驱动，四位一体数码管南华大学电气工程学院课程设计iiAbstract：SCMbeboomingsincesincethe70s,MCUfunctionsareincreasinglyperfectatpresent:singlechipmicrocomputerintegratedmoreandmoreresources,internalstorageresourceincreasinglyrich,usersdonotneedtoexpandresourcescancompletetheprojectdevelopment,isnotonlythedevelopmentofsimple,smallbeautifulproducts,atthesametime,stronganti-jammingcapability,systemismorestable,makeitmoresuitableforindustrialcontrolfield,hasabroadmarketprospect;Provideonlineprogrammingability,speededuptheprocessofproductdevelopment,productfortheenterprisetowintheprecioustime.ThisdesignandtriodedrivenbySTC89C51microcontrollerandthesinglechipmicrocomputerminimumsystemandperipheralkeysanddigitaltubedisplaycomponents,designasimpletimerbasedonsinglechipmicrocomputer.Designthroughthefourdigitaltubedisplay,atotalofanode,andcanthroughthebuttontosettheseconds.Keywords:STC89C51microcontroller,drive,Fourdigitaltube南华大学电气工程学院课程设计iii目录引言...................................................................................................................................11.设计任务及基本要求.......................................................................................................22.系统基本方案选择与论证...............................................................................................22.1单片机选择............................................................................................................22.2显示模块选择方案和论证：................................................................................23.主要元件介绍...................................................................................................................33.1STC89C51介绍.......................................................................................................33.1.1STC89C51主要功能及DIP封装................................................................33.1.2STC89C51引脚介绍....................................................................................43.2数码管介绍............................................................................................................73.2.1四位一体数码管概述.................................................................................73.2.2四位一体数码管引脚图.............................................................................73.3自锁开关说明.........................................................................................................83.4上拉电阻介绍.........................................................................................................83.5三极管介绍.............................................................................................................93.6按键介绍............................................................................................................114.系统硬件设计.................................................................................................................124.1电路设计框图......................................................................................................124.2系统硬件概述......................................................................................................125.系统软件设计.................................................................................................................126.调试.................................................................................................................................146.1硬件调试..............................................................................................................146.2软件调试..............................................................................................................157.结论.............................................................................................................................15参考文献.............................................................................................................................16附录1原理图....................................................................................................................17附录2源程序....................................................................................................................18附录3元件清单................................................................................................................20南华大学电气工程学院课程设计iv附录4实物图....................................................................................................................21南华大学电气工程学院课程设计第1页共21页引言时钟，自从它发明的那天起，就成为人类的朋友，但随着时间的推移，科学技术的不断发展，人们对时间计量的精度要求越来越高，应用越来越广。怎样让时钟更好的为人民服务，怎样让我们的老朋友焕发青春呢？这就要求人们不断设计出新型时钟。现今，高精度的计时工具大多数都使用了石英晶体振荡器，由于电子钟，石英表，石英钟都采用了石英技术，因此走时精度高，稳定性好，使用方便，不需要经常调校，数字式电子钟用集成电路计时时，译码代替机械式传动，用LED显示器代替显示器代替指针显示进而显示时间，减小了计时误差，这种表具有时，分，秒显示时间的功能，还可以进行时和分的校对，片选的灵活性好。一、时间被认为是最宝贵的资源，为了对时间有更深刻的了解，同时也在电子方面有更深刻的认识，通过学习，本次设计主要介绍用单片机内部的定时/计数器来实现电子秒表的方法，本设计由单片机STC89C5