【正文】 tion chip 8255A is the central ponent designs the traffic light controller, realized has been able to act according to the actual traffic flow magnitude to establish, the green light red through 8051 chip P1 mouths burns the bright time the function。本系統(tǒng) 實(shí)用性強(qiáng) 、 操作簡(jiǎn)單 、擴(kuò)展功能強(qiáng) 。交通信號(hào)燈控制方式很多。 十字路口車輛 穿梭 ，行人熙攘，車行車道，人行人道，有條不紊。 畢業(yè)論文 基于單片機(jī)交通燈的控制 專 業(yè) ： 應(yīng)用電子技術(shù) 摘要 I 摘 要 近年來隨著科技的飛速發(fā)展，單片機(jī)的應(yīng)用正在不斷深入，同時(shí)帶動(dòng)傳統(tǒng)控制檢測(cè)技術(shù)日益更新 。在實(shí)時(shí)檢測(cè)和自動(dòng)控制的單片機(jī)應(yīng)用系統(tǒng)中，單片機(jī)往往作為一個(gè)核心部件來使用，僅單片機(jī)方面知識(shí)是不夠的，還應(yīng)根據(jù)具體硬件結(jié)構(gòu)軟 硬 件結(jié)合，加以完善?？康?就 是交通信號(hào)燈的自動(dòng)指揮系統(tǒng)來實(shí)現(xiàn)這井然秩序。本系統(tǒng)采用 MSC51系列單片機(jī) ATSC51和可編程并行 I/O接口芯片 8255A為中心器件來設(shè)計(jì)交通燈控制器，實(shí)現(xiàn)了能根據(jù)實(shí)際車流量通過 8051 芯片的 P1 口設(shè)置紅、綠燈燃亮?xí)r間的功能 ；紅綠燈循環(huán)點(diǎn)亮，倒計(jì)時(shí)剩 5 秒時(shí)黃燈閃爍警示（ 交通燈信號(hào)通過 PA 口輸出 ， 顯示時(shí)間直接通過 8255 的 PC口 輸出 至雙位數(shù)碼管） ； 車輛闖紅燈報(bào)警；綠燈時(shí)間可檢測(cè)車流量并可通過雙位數(shù)碼管顯示。 。 The traffic light circulation lightens, the countdown remains when for 5 seconds the yellow light twinkle police shows (traffic light signal through PA mouth output, demonstration time directly through 8255 PC mouth output to twoposition nixietube)。 The green light time may examine the traffic flow magnitude and may through the twoposition nixietube system usability strong, operation simple, expansion function. Keywords： monolithic integrated circuit traffic light runs a red light the examination traffic flow magnitude 目錄 III 目 錄 摘 要 ............................................................................................................................................. I ABSTRACT .................................................................................................................................. II 目 錄 .......................................................................................................................................... III 第 1 章 緒論 ...................................................................................................................................1 第 2 章 總體規(guī)劃方案 ...................................................................................................................4 規(guī)劃設(shè)計(jì)方案 .......................................................................................................................4 交通管理的方案論證 ...........................................................................................................4 第 3 章 系統(tǒng)的芯片簡(jiǎn)介 ...............................................................................................................6 MSC51 芯片簡(jiǎn)介 .................................................................................................................6 MCS51 單片機(jī)內(nèi)部 結(jié)構(gòu) ..............................................................................................6 MCS51 的引腳和功能概述 ..........................................................................................8 8255 芯片簡(jiǎn)介 ....................................................................................................................9 8255A 的內(nèi)部結(jié)構(gòu) ........................................................................................................9 8255 可編程并行接口芯片簡(jiǎn)介 .................................................................................. 11 第 4 章 系統(tǒng)硬件設(shè)計(jì) .................................................................................................................15 系統(tǒng)總框圖設(shè)計(jì) .................................................................................................................15 各個(gè)模塊電路設(shè)計(jì) .............................................................................................................16 鍵盤設(shè)置電路 ..............................................................................................................16 看門狗硬件電路 ..........................................................................................................19 顯示電路 ......................................................................................................................20 交通燈的控制電路 ......................................................................................................21 第 5 章 系統(tǒng)的軟件設(shè)計(jì) .............................................................................................................23 系 統(tǒng)總程序設(shè)計(jì) .................................................................................................................23 每秒鐘的設(shè)定 .....................................................................................................................24 計(jì)數(shù)器初值計(jì)算 ...........................................................................................................24 計(jì)算公式 ......................................................................................................................24 １秒的方法 ..................................................................................................................25 相應(yīng)程序代碼 ..............................................................................................................25 軟件延時(shí) ......................................................................................................................26 顯示程序設(shè)計(jì) .....................................................................................................................27 顯示原理 .......................................................................................................................27 8255 輸出信號(hào)與數(shù)碼管的連接 ..................................................................................27 8255 與 8051 的連接 ....................................................................................................28 第 6 章 結(jié)論 .................................................................................................................................29 參考文獻(xiàn) .......................................................................................................................................30 目錄 IV 致 謝 ........