文档介绍：论文题目基于单片机超声波测距器设计
学生姓名
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专业
班级
指导教师
2011年5月
摘要
本文介绍了一种基于STC89C52单片机的超声波液位测量系统,阐述了超声波液位测量系统的硬件电路构成、工作原理及软件设计方法。超声波发生器在某一时刻发出一个超声波信号,当超声波遇到被测液体后反射回来,就被超声波接收器所接收。这样只要计算出从发射信号到接收返回信号所用的时间,就可算出超声波发生器与反射物体之间的距离。硬件部分采用STC89C52 单片机作为主控单片机,电路部分主要有发射电路、接收电路、显示电路几部分组成。超声波发射电路主要由反向器74LS04和超声波传感器构成, 超声波接收电路主要是由集成电路CX20106A组成,显示电路用动态扫描法实现LED数字显示以及通过串口通信。设计出的超声波液位测量系统精度可达厘米数量级,电路具有结构简单、操作方便、精度高、应用广泛的特点。
关键词:超声波测距;STC89C52单片机;数字显示
ABSTRACT
The paper describes an ultrasonic measuring liquid-level system based on the STC89C52 , it described an ultrasonic measuring liquid-level system hardware circuit structure, working principle and software design methods. Ultrasonic generator at a time sent an ultrasonic signal, when the ultrasonic wave reflected back upon the detected objects encountered, they were received ultrasonic receiver. So as long as calculated from the emission signal to the receiver to return the signal used in the time, you can calculate the ultrasonic generator and the distance between the reflective object. Hardware using STC89C52 microcontroller as a master MCU, the circuit part of the main transmitter, receiver circuit, display circuit of several parts. Ultrasonic transmitter device mainly by reverse 74LS04 and the ultrasonic position, ultrasonic receiver circuit is posed of CX20106A integrated circuits, display circuits using the LED digital display at the real time. The system hardware structure is simple, reliable, good accuracy and system's accuracy could reach centimeter orders of were simply structure,easy to use,high accuracy and wide application.
KEY WORDS: Ultrasonic; measuring liquid-level;STC89C52 MCU;Digital display
目录
1 绪论 1
课题设计的目的和意义 1
课题设计的研究范围和成果 1
课题设计的任务和要求 2
2 总体设计方案 3
3 硬件电路各部分设计 5
单片机系统及显示电路 5
主控芯片STC89C52 5
数码管显示原理 8
超声波发射电路 9
超声波检测接收电路 10
超声波的硬件电路设计 12
4 系统软件设计 13
超声波测距器的算法设计 13
主程序设计 13
超声波发生子程序和接收中断程序 14
5 调试及性能分析 17
调试