目 录
1 绪论..................................................................................................................................1
1.1 选题背景..................................................................................................................1
1.2 环境监测仪发展过程..............................................................................................2
1.3 环境监测仪发展前景..............................................................................................3
2 环境监测仪的工作原理及主要器件介绍......................................................................4
2.1 整体设计思路...........................................................................................................4
2.2 单片机 MSP430.......................................................................................................5
2.2.1 单片机 MSP430 简介...................................................................................5
2.2.2 单片机 MSP430 主要特点...........................................................................5
2.2.3 单片机 MSP430 工作模式...........................................................................7
2.2.4 单片机 MSP430 端口介绍...........................................................................8
2.3 温湿度传感器 SHT11 ...........................................................................................10
2.3.1 温湿度传感器 SHT11 介绍 .......................................................................10
2.3.2 温湿度传感器 SHT11 特点及应用领域 ...................................................10
2.3.3 温湿度传感器 SHT11 工作原理 ...............................................................11
2.4 气压传感器 MPX4105 .............................................................................................14
2.5 I
2
C 总线定义........................................................................................................15
3 系统硬件的设计............................................................................................................17
3.1 温湿度传感器 SHT11 电路 ...................................................................................17
3.2 气压传感器 MPX4105 ...........................................................................................18
3.3 LCD 显示................................................................................................................18
3.4 复位电路部分.........................................................................................................21
3.5 时钟电路部分.........................................................................................................22
3.6 超限处理电路.........................................................................................................25
3.7 键盘电路.................................................................................................................26
