摘 要：随着我国经济的飞速发展，人民的生活水平提高，机动车辆的总体拥有量也逐年递增，其虽在表面上展现了我国近40年改革开放的丰硕成果，然而从深层次上看影响城市的交通安全甚至于严重制约了社会主义社会的建设。几十年来，许多设计师以改善十字路口交通为课题进行研究，设计了多种新型有效的方案，为我国的交通建设作出了杰出的贡献。现今，十字路口都大量采用了交通灯来控制车辆与路人的通行，不仅利于维护与管理，而且具有自动化这一优势。数字化、小功率、多样化、多值化、有效的协调人和车之间的关系已成为交通灯的发展趋势，如何成功缓解交通负担以及减少交通事故的发生也成为设计的重点。本设计是基于单片机AT89C51来设计智能交通灯系统，是通过在软件和硬件部分进行设计实现在不同的交通情况下采取不同的模式，正常情况下红绿黄灯按规律点亮，其中黄灯是倒计时5秒时点亮闪烁，特殊情况下十字路口红灯全部亮起，夜间模式下十字路口黄灯亮起。93162

毕业论文关键字：十字路口交通，交通灯，AT89C51单片机，倒计时

Abstract：With the rapid development of China's economy, people's living standards improve, the ownership of motor vehicles is increasing year by year, although on the surface show fruitful results in China in the past 40 years of reform and opening up, but from the deep influence of the city's traffic safety and even seriously restrict the construction of the socialist society。 For decades, many designers have done a lot of research on the improvement of crossroad traffic, designed a variety of new and effective solutions, and made outstanding contributions to the construction of traffic in china。 Today, a large number of intersections are used to control traffic lights and passers-by, not only conducive to maintenance and management, but also has the advantage of automation。 Digital, low power, multi value persification, coordinate the relationship between people and cars, effectively has already become the development trend of traffic lights, to alleviate traffic burden and reduce traffic accidents have become the focus of the design。 This design is to design the intelligent traffic light system based on single chip AT89C51, is designed by adopting different models in different traffic conditions in software and hardware, under normal circumstances, red and yellow light according to the law of light, the yellow light is the countdown 5 seconds when the light flashes, red light all the special circumstances at the crossroads at night, under the yellow light at the crossroads。

Keywords：Crossroads traffic, traffic lights, AT89C51 microcontroller, countdown

目录

1 前言 4

1。1 交通信号灯的发展历史 4

1。2 研究交通信号灯的意义 4

1。3 单片机的简介 4

2 方案设计与论证 5

2。1 供电方案 6

2。2 显示界面方案 6

2。3 输入方案 6

3 系统的硬件设计 7

3。1 总体设计 7

3。2 单片机AT89C51 7

3。2。1 单片机AT89C51主要性能参数 7

3。2。2 AT89C51功能特性 8

3。2。3 AT89C51的引脚功能 8

3。3 单片机外围电路设计