封面目录摘要.................................................................................................................................................1一.绪论............................................................................................................................................2二．超声波测距的原理...................................................................................................................32.1超声波的基本理论.....................................................................................................................32.2超声波测距系统原理.................................................................................................................7三.系统硬件的具体设计与实现.....................................................................................................83.1系统原理和框图........................................................................................................................83.2功能模块的设计........................................................................................................................83.2.1单片机介绍...................................................................................................................83.2.1.1STC89C52管脚说明..........................................................................................93.2.1.2STC89C52主要特性........................................................................................103.2.1.3芯片擦除..........................................................................................................113.2.2超声波测距模块HC-SR04......................................................................................113.2.2.1产品特点.........................................................................................................113.2.2.2基本原理.........................................................................................................123.2.2.3电气参数.........................................................................................................123.2.2.4超声波时序图.................................................................................................123.2.3LCD1602液晶显示....................................................................................................133.2.3.1.引脚说明.......................................................................................................133.2.3.2字符显示地址说明..........................................................................................133.2.3.3.读写时序操作...............................................................................................143.2.4DS18B20温度传感器..................................................................................................143.2.4.1.芯片简介.......................................................................................................143.2.4.2DS18B20外形和内部结构............................................................................153.2.4.3DS18B20与单片机的典型接口设计............................................................17四.系统软件设计..........................................................................................................................194.1.程序设计思路..........................................................
