【正文】 西安航空職業(yè)技術(shù)學(xué)院制 年 月 日 2 西安航空職業(yè)技術(shù)學(xué)院 畢業(yè)設(shè)計(jì)（論文）任務(wù)書 題目： 任務(wù)與要求： 時(shí)間： 年 月 日 至 年 月 日 共 周 所屬系部： 學(xué)生姓名： 學(xué) 號(hào)： 專業(yè)： 指導(dǎo)單位或教研室： 指導(dǎo)教師： 職 稱： 西安航空職業(yè)技術(shù)學(xué)院制 年 月 日 畢業(yè)設(shè)計(jì) (論文 )進(jìn)度計(jì)劃表 3 日 期 工 作 內(nèi) 容 執(zhí) 行 情 況 指導(dǎo)教師 簽 字 教師對(duì)進(jìn)度計(jì)劃實(shí)施情況總評(píng) 簽名 年 月 日 本表作評(píng)定學(xué)生平時(shí)成績的依據(jù)之一。 4 基于單片機(jī)數(shù)字秒表的設(shè)計(jì) 【 摘要 】 近年來隨著科技的飛速發(fā)展，單片機(jī)的應(yīng)用正在不斷的走向深入。本設(shè)計(jì)主要 特點(diǎn)是計(jì)時(shí)精度達(dá)到 ，解決了傳統(tǒng)的由于計(jì)時(shí)精度不夠造成的誤差和不公平性，是各種體育競賽的必備設(shè)備之一。將軟、硬件有機(jī)地結(jié)合起來，使得系統(tǒng)能夠?qū)崿F(xiàn)兩位 LED 顯示，顯示時(shí)間為 0～ 秒，計(jì)時(shí)精度為 秒，能正確地進(jìn)行計(jì)時(shí)，同時(shí)能記錄一次時(shí)間，并在下一次計(jì)時(shí)后對(duì)上一次計(jì)時(shí)時(shí)間進(jìn)行查詢。 關(guān)鍵字：單片機(jī)；數(shù)字電子秒表；仿真 I Abstract With the rapid development of science and technology in recent years, SCM applications are constantdepth manner. In this paper, based on single chip design of digital electronic stopwatch. The main characteristics of this design timing accuracy of , to solve the traditional result of a lack accuracy due to timing errors and unfair, and is a variety of sports petitions, one of the essential equipment. In addition the hardware part of the set View button on the stopwatch can be the last time to save time for user queries. The design of the multifunction stopwatch system uses STC89C52 microcontroller as the central device, and use its timer / counter timing and the count principles, bined with display circuit, LED digital tube, as well as the external interrupt circuit to design a timer. The software and hardware together anically, allowing the system to achieve two LED display shows the time from 0 to seconds, Timing accuracy of seconds, Be able to correctly time at the same time to record a time, and the next time after the last time the time to search automatically added a second in which software systems using assembly language programming, including the display program, timing, interrupt service, external interrupt service routine, delay procedures, key consumer shaking procedures, and WAVE in the missioning, operation, hardware system uses to achieve PROTEUS powerful, simple and easy to observe the cut in the simulation can be observed on the actual working condition. Keyword： LED display； Highprecision stopwatch； 8051 1 目 錄 緒 論 ..............................................................................................................................................................2 1 引言 ...............................................................................................................................................................3 秒表及其發(fā)展現(xiàn)狀 .............................................................................................................................3 設(shè)計(jì)方案 ..............................................................................................................................................3 設(shè)計(jì)內(nèi)容 .......................................................................................................................................3 設(shè)計(jì)要求 .......................................................................................................................................4 系統(tǒng)方案 ......................................................................................................................................4 2 元器件的概述及選擇 ................................................................................................................................5 單片機(jī)的選擇 .....................................................................................................................................5 AT89C51 單片機(jī)介紹 ..................................................................................................................5 74LS164 的介紹 .........................................................................................................................6 兩位 LED數(shù)碼管顯示 .................................................................................................................8 3 數(shù)字秒表硬件設(shè)計(jì) ................................................................................................................................. 10 單片機(jī)硬件設(shè)計(jì) .............................................................................................................................. 10 數(shù)字秒表電路設(shè)計(jì) .................................................................................................................... 10 電源電路 ....................................................................................................................................11 晶振電路的選擇與設(shè)計(jì) ............................................................................................................11 復(fù)位電路的選擇與設(shè)計(jì) ........................................