目录
1 绪论....................................................................................................................5
1.1 研究的背景及意义.................................................................................5
1.2 现状及发展趋势.....................................................................................7
1.3 主要工作.................................................................................................9
1.4 本章小结..................................................................................................9
2 系统方案设计..................................................................................................10
2.1 系统总体方案.......................................................................................10
2.2 硬件系统方案.......................................................................................10
2.3 软件系统方案.......................................................................................11
2.4 本章小结................................................................................................11
3 硬件系统设计..................................................................................................12
3.1 单片机模块...........................................................................................12
3.1.1 STC90C516RD 的参数及特点 ..................................................12
3.1.2 单片机各引脚及功能................................................................13
3.1.3 单片机最小系统模块................................................................15
3.2 甲醛传感器模块...................................................................................16
3.2.1 传感器的选择............................................................................16
3.2.2 传感器原理及参数....................................................................16
3.2.3 传感器模块引脚........................................................................17
3.2.4 甲醛传感器模块的串口通信协议............................................18
3.3 串口 WiFi 模块.....................................................................................19
3.3.1 WiFi 模块特性............................................................................19
3.3.2 WiFi 模块的基本参数................................................................20
3.3.3 WiFi 模块的 AT 指令 ................................................................22
3.3.4 WiFi 模块的云端通信................................................................23
3.4 液晶显示模块........................................................................................24
3.4.1 液晶显示模块的概述................................................................24
3.4.2 显示模块引脚说明....................................................................25
3.4.3 显示模块操作............................................................................25
3.4.4 RAM 映射表及字库对照表.......................................................28
3.5 蜂鸣器模块...........................................................................................30
3.6 电源降压模块.......................................................................................30
