摘要：交通灯的使用能够对车辆通行和人流疏导进行有效的管制与疏散，在交叉路口安置交通信号灯更是提高道路导通能力、维护道路安全与秩序的最佳方式。本系统选取AT89S51作为核心部件，搭配74HC245芯片和四个两位一体共阴数码管，硬件与软件设计相结合，通过C语言进行程序编程，设置四面红灯、四面黄灯、只允许单一通道行车和实时时间加减功能。当检测到有按钮按下时系统产生中断，停止刚才的程序转向中断执行，有效解决交通阻塞、等待时间不合理、急通车、夜间行车等实际问题。该系统结构简单合理、可靠性高、实时性好，能较好的仿真模拟出实际情景中对交通路面的控制，且安装与维护方便，具有广泛的应用前景。91487

毕业论文关键词： 单片机，交通灯，数码管

Abstract：The use of traffic lights can effectively control and evacuate vehicle traffic and traffic flow, and the placement of traffic lights at intersections is the best way to improve  road continuity and maintain road safety and order。 The system selected AT89S51 as the core components, with 74HC245 chip and four two-in-one digital tube, hardware and software design, through the C language programming, set four red, four yellow, only a single channel traffic As well as real-time time addition and subtraction function。 When a button is pressed, the system generates an interrupt and stops the program's turn to interrupt execution, it is an effective solution to traffic congestion, waiting time unreasonable, rush, night driving and other practical problems。 The system has the advantages of simple structure, high reliability, good real - time performance, easy installation and maintenance, and good simulation to simulate the control of traffic pavement in the actual situation, and has wide application prospect。

Keywords： Microcontrollers,The traffic light,LED

目 录

1 前言 4

1。1系统设计背景 4

1。2系统设计意义 4

1。3国内外现状及水平 5

2系统总体设计方案 5

2。1设计要求 5

2。2设计方案选择 5

2。3设计思路 6

2。4设计方案介绍 7

3系统硬件设计 8

3。1单片机芯片的选择 9

3。2系统构成 9

3。3AT89S51单片机的最小系统 10

3。474HC245芯片介绍 10

3。5系统的运行 11

4系统软件设计 11

4。1程序流程图 11

4。2程序语言环境 12

4。3程序的设计 13

5系统测试与分析 17

5。1系统硬件测试 17

5。2系统仿真测试 18

5。3单片机实物调试 20

结论 24

参考文献 25

致谢 26

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