摘要现在人们的生活水平在不断地提高，汽车成为人们日常出行的重要代步工具。但是夜间行车受道路状况和不当的驾驶习惯影响，传统的汽车前照灯很难满足驾驶员的视线要求，很容易导致交通事故的发生。传统前照灯的安全性受到了质疑。而新课题智能化前照灯能弥补传统前照灯的不足。所以，智能前照灯成为了汽车行业研究的主流趋势。

本文采用单片机作为主控制器，设计了一款汽车LED前向灯的智能控制系统，并且给出了总体设计框图、完成了系统硬件部分的设计和选型。系统以STC89C52单片机最小系统为核心，包含有超声波测距电路、利用PCF8591进行监测的方向盘转角检测电路、继电器前照灯方向控制电路，LCD1602显示电路等。利用PROTEL软件绘制了电路原理图，并用PROTUES进行了部分模块的仿真。然后进行软件部分的设计和C语言编程。整个系统通过对前方物体距离和方向盘转角的实时监测，对前照灯进行实时控制。最终完成的系统符合设计任务要求，有集成度高、实效性好、制造成本低廉等优点。84383

毕业论文关键词：单片机；前照灯；距离测量；LCD1602

Abstract As people's living standard has been improved these years,Cars play an important role in people's daily life。Because of the complex conditional of street and the driver’s wrong habit，the traditional car headlamps are difficult to meet the drivers’ requirements of vision,it is easy to lead to the occurrence of traffic accidents。The security of the traditional headlight system was backward。But the design of intelligent control system of automotive LED headlamps can solve these problems。Improvement an innovation system has become popular in the automotive industry。

In this paper, the intelligent control system is designed by using single chip microcomputer, and be completed with the design block diagram。Then I introduce the hardware composition 。 This system with the minimum system of the one chip computer as the core, main component is STC89C52 micro-controller ,contain the ultrasonic distance measuring circuit, the headlight lamp direction control circuit by PCF8591,relay headlight direction control circuit, LCD1602 display circuit, etc。。 Then I use PROTEL to draw a circuit diagram,the key technology is emulated by PROTUES。After this,I write program by using C++ language。 By real-time monitoring of the light intensity and steering wheel angle, the system can control the real time of the headlight。 The whole system has the advantages of high degree of collection, good real-time performance and low cost。

Keywords: Single chip microcomputer; Headlight; Light distance measurement;  LCD1602;

目录

摘要 VII

Abstract VIII

第一章 绪论 1

1。1课题研究的目的和意义 1

1。2前照灯控制系统的国内外研究现状 2

1。3 需求分析 3

第二章 汽车前照灯智能控制系统总体方案设计 6

2。1前照灯智能控制系统主要组成框图 6

2。2前照灯智能控制系统工作原理 6

2。3单片机技术选型的技术指标 7

2。3。1 STC89C52单片机的性能介绍 8

2。3。2 STC89C52单片机引脚功能介绍 8

2。3。3 STC89C52单片机复位电路介绍 9

2。3。4 STC89C52单片机时钟电路介绍