目 录
绪 论 ..........................................................................................................................................1
1 方案设计 ..............................................................................................................................2
1.1 总体框架的设计 ........................................................................................................2
1.2 单片机开发环境的选择 ............................................................................................3
1.2.1 电路图绘制软件 ..............................................................................................3
1.2.2 Keil_C 软件......................................................................................................4
2 硬件电路设计 ......................................................................................................................6
2.1 传感器的选型 ............................................................................................................6
2.2 单片机最小系统设计 ................................................................................................6
2.2.1 单片机的选型 ..................................................................................................6
2.2.2 时钟电路与复位电路 ......................................................................................8
2.2.3 单片机使用注意事项 ....................................................................................10
2.3 电流电压转换电路设计 ..........................................................................................11
2.4 模拟量采集电路设计 ..............................................................................................13
2.4.1 ADC0809 概述...............................................................................................13
2.4.2 ADC0809 与单片机接口电路.......................................................................15
2.5 显示电路设计 ..........................................................................................................16
2.5.1 LCD1602 引脚结构 .......................................................................................16
2.5.2 LCD1602 主要技术参数及特性 ...................................................................16
2.5.3 LCD1602 与单片机的接口电路 ...................................................................17
2.6 按键接口电路设计 ..................................................................................................17
2.7 报警电路设计 ..........................................................................................................18
2.8 串行口功能设计 ......................................................................................................19
2.8.1 RS-232 串行接口........................................................................................... 19
2.8.2 MAX232 简介................................................................................................20
3 软件部分设计 ....................................................................................................................22
3.1 主程序工作流程 ......................................................................................................22
3.2 A/D 转换子程序 ......................................................................................................23
3.3 数字滤波及标度变换程序设计 ..............................................................................24
III
