摘要超声波拥有较强的指向性，能量消耗的速度慢，具有传播距离远等特点，因此，在利用自动控制技术和传感器技术相结合的测距方案中，超声波测距的应用十分广泛，它在汽车倒车雷达、水位检测、移动机器人避障与定位等很多领域被广泛的应用。72713

 本设计使用STC89C52单片机与HC-SR04超声波测距模块来测量到障碍物的距离，用LCD1602液晶模块来实现距离的显示，使用DS18B20温度传感器来进行温度补偿以提高测量精度，通过按键可以设置距离报警值的上限和下限，此外，本设计含有串口通信模块，通过该模块，PC机可以和单片机进行通信。本论文介绍了STC89C52单片机的基本原理和使用方法，并在研究超声波测距的理论基础之上，发现超声波测距系统测量不够准确，把温度对测距的影响考虑在内，设计出了以STC89C52单片机为核心的带温度补偿的超声波测距系统。本设计介绍了各个模块的作用和基本的编程方法，本设计的硬件成本较低，系统工作十分稳定，测距精度也可以达到很高的水平。

毕业论文关键词：单片机  串口通信  超声波测距  温度补偿  报警

Ultrasonic Ranging System Based on Serial Communication Design

Abstract Ultrasound has strong directivity, slow energy consumption, propagation distance and so has, therefore, in the use of automatic control technology and sensor technology combines ranging scheme, ultrasonic distance measurement is widely used, it is in the car reversing radar in many areas, the water level detection, mobile robot obstacle avoidance and other location being widely used。

 This design uses STC89C52 MCU and HC-SR04 ultrasonic ranging module to measure the distance to an obstacle, with the LCD1602 LCD display module to achieve the distance, use DS18B20 temperature sensor for temperature compensation to improve the measurement accuracy, you can set the alarm distance through the key upper and lower values, in addition, the design contains a serial communication module, through this module, PC machine and MCU can communicate。 This paper introduces the basic principles STC89C52 microcontroller and use, and basic research in the theory of ultrasonic ranging above, we found that ultrasonic ranging measurement system is not accurate enough, the temperature ranging impact into account, in order to design a STC89C52 microcontroller as the core temperature compensated ultrasonic ranging system。 This design introduces the role and basic programming of each module, the lower cost of the hardware design, system works very stable, ranging accuracy can achieve very high levels。

Key words: microcontroller  serial communication  ultrasonic distance measurement  temperature compensation  alarm

目录

摘要 I

Abstract II

目录 III

图清单 V

表清单 V

1 绪 论 1

1。1 研究的背景和意义 1

1。2超声波测距的发展现状趋势 2

1。3超声波原理及应用 3

1。4超声波测距原理 4

1。5主要设计内容 5

2 总体方案及芯片介绍 6

2。1电路设计思路和总体方案 6

2。2芯片介绍