【正文】 mer is introduced in detail. Hardware is mainly posed of display module, keys module, reset module, a crystal vibration circuit and so on。硬件主要由顯示模塊、按鍵模塊、復(fù)位模塊、晶振電路等組成；軟件是用 C 語言編程，再利用 Keil 軟件進(jìn)行仿真，最后將軟硬件結(jié)合起來實(shí)現(xiàn)電子計(jì)時器的功能。具有簡單易操作、時間可以任意設(shè)定等優(yōu)點(diǎn)，適合目前人們對智能小家電的需求。通過比較，本課題選擇了“基于 AT89S51 單片機(jī)的電子計(jì)時器”的設(shè)計(jì)方案。摘 要本設(shè)計(jì)是以 AT89S51 單片機(jī)為核心實(shí)現(xiàn)的一個智能電子計(jì)時器系統(tǒng)。目前市場上的電子計(jì)時器，主要有基于 NE555 的電子計(jì)時器、基于脈沖的電子計(jì)時器以及基于 AT89S51 單片機(jī)的電子計(jì)時器三種。該方案利用了 AT89S51 單片機(jī)為主控芯片，實(shí)現(xiàn)了時間顯示、定時中斷以及記錄比分等功能。本設(shè)計(jì)主要從總體設(shè)計(jì)、硬件設(shè)計(jì)、軟件設(shè)計(jì)、系統(tǒng)實(shí)現(xiàn)等方面來對智能電子計(jì)時器進(jìn)行詳細(xì)的介紹。本設(shè)計(jì)主要是完成定時時功能，該計(jì)時器系統(tǒng)簡單易操作，定時時間也較長，適合在 999 秒以內(nèi)的定時，比如豆?jié){機(jī)、榨汁機(jī)等的定時。 Software is written in C language programming, using the Keil software simulation, electronic timer function is realized by bining software and hardware.Timing of the pletion of this design is mainly the function, the timer system easy to operate, simple timing time is longer, suitable time within 999 seconds, such as timing DouJiangJi, juicer and so on.Keywords: AT89S51, LED digital tube, electronic timer, the C language目 錄第一章 緒論 ...................................................................................................................................1第二章 電子計(jì)時器及 AT89S51 單片機(jī)的簡介 ...........................................................................2 電子計(jì)時器的的功能以及工作原理 ..................................................................................2 電子計(jì)時器的功能簡述 .............................................................................................2 電子計(jì)時器的工作原理及組成 .................................................................................2 AT89S51 單片機(jī)的簡介 ........................................................................................................3 AT89S51 功能特性概述 ................................................................................................3 AT89S51 的引腳圖及說明 ............................................................................................4第三章 系統(tǒng)的總體設(shè)計(jì) .................................................................................................................8 方案比較 ...............................................................................................................................8 功能設(shè)計(jì) ............................................................................................................................10 功能實(shí)現(xiàn)流程 ....................................................................................................................10第四章 硬件設(shè)計(jì) .........................................................................................................................12 單片機(jī)最小系統(tǒng) .................................................................................................................12 電子計(jì)時的功能模塊 .........................................................................................................14 繼電器模塊 ..........................................................................................................................14 按鈕模塊 ..............................................................................................................................15 顯示模塊 ..............................................................................................................................16第五章 軟件設(shè)計(jì) .........................................................................................................................19 C 語言簡介 .........................................................................................................................19 軟件模塊規(guī)劃 ....................................................................................................................20 程序?qū)崿F(xiàn) ............................................................................................................................21 程序的功能模塊 ..........................................................................................................22 主程序設(shè)計(jì) ..................................................................................................................22 中斷程序設(shè)計(jì) ..............................................................................................................23 其他子程序的設(shè)計(jì) ......................................................................................................24第六章 系統(tǒng)實(shí)現(xiàn) ...........................................................................................................................26 硬件實(shí)現(xiàn) ............................................................................................................................26 軟件調(diào)試 ............................................................................................................................27 系統(tǒng)功能測試 .......................................................