毕业设计（论文）-基于单片机和超声波模式的测距系统设计.doc

摘要 由于超声波指向性强，能量消耗缓慢，在介质中传播的距离较远，因而超声波经常用于距离的测量，如测距仪和物位测量仪等都可以通过超声波来实现。Abstract Because of ultrasonic directionality is strong, energy consumption is slow, in the medium of communication distance, so often used for the measurement of ultrasonic distance, such as rangefinder and material level measurement instrument, etc can all through the ultrasonic to achieve. Use of ultrasonic detection tend to be quickly, convenient and simple calculation, easy to do real-time control, and in the measurement precision can reach industry practical requirement, so in reverse radar system widely applied. The ultrasonic ranging system adopt modularization design circuit, by ultrasound receiving module, LCD display module, temperature detection module, alarm module. Through the software programming make hardware function through comprehensive treatment of single chip achieved get. Program has main program, launch procedure, receiving a subroutine, display procedure, etc. This design anti-interference ability is good, good real-time performance, error can achieve mm level, can effectively solve the car back to indoor temperature and the problem of perception. The system through the STC89C52 single-chip microcomputer control so as to realize the back-draft process cars and obstacles of the distance between the shows, when cars and obstacle distance to a value less than when the automatic alarm, this system also has the temperature alarm function. Through the button lowest highest temperature, when environment temperature more than cap or lower limit, control system timely alarm functions. Keywords：MCU STC89C52，ultrasonic distance sensor，temperature transmitter，Parking Distance Control 目录 摘要 Ⅰ Abstract Ⅱ 1. 绪论 1 1.1课题背景及意义 1 1.2超声波简介 1 1.3课题的主要内容 2 2. 系统的总体设计方案 3 2.1超声波传感器测距原理 3 2.2硬件子系统设计 4 2.3软件子系统设计 5 2.4超声波测距系统主要器件选定 6 3．硬件电路设计 15 3.1 单片机最小系统 15 3.2超声波发射电路设计 16 3.3超声波接收电路设计 16 3.4系统电源 18 3.5 液晶显示电路 18 3.6 键盘电路设计 19 3.7温度检测电路设计 19 3.8报警电路设计 20 4. 超声波测距系统软件设计 21 4.1 KeilμVision3简介 2