目录摘要.......................................................................................................................................................................2ABSTRACT..............................................................................................................................................................3目录...................................................................................................................................................................41绪论.......................................................................................................................................................................11.1概述.................................................................................................................................................................11.2国内外发展现状.............................................................................................................................................12系统总体方案设计...............................................................................................................................................22.1设计要求.........................................................................................................................................................21）可进行距离测量。.............................................................................................................................................22）采用数码管显示距离数据。...........................................................................................................................23）可按键设置距离门限值...................................................................................................................................24）具有报警功能...................................................................................................................................................22.2方案选择.........................................................................................................................................................22.2.1单片机的选择...........................................................................................................................................23系统硬件设计.......................................................................................................................................................23.1整体方案设计.................................................................................................................................................23.1.1系统概述...................................................................................................................................................23.1.2系统框图...................................................................................................................................................33-1系统框图...........................................................................................................................................................33.2最小系统模块.................................................................................................................................................33.2.1STC89C52简介..................................................
