目 录
1 绪 论 ..........................................................................................................................................1
1.1 研究背景和意义...............................................................................................................1
1.1.1 课题研究背景分析...............................................................................................1
1.1.2 课题研究意义.......................................................................................................1
1.2 本课题国内外的研究现状...............................................................................................2
1.3 本课题的研究内容...........................................................................................................3
2 LED 开关老化测试系统的主要原理............................................................................................4
2.1 LED LM-80 光通维持-寿命试验原理 ...............................................................................4
2.2 基于 PWM 脉宽调制的 LED 老化测试原理....................................................................4
3 系统硬件设计与实现...................................................................................................................8
3.1 ATmega 2560 简介 ...........................................................................................................8
3.2 CH340 USB 模块设计 .......................................................................................................9
3.3 LED 驱动模块设计..........................................................................................................11
3.4 蓝牙通讯模块设计.........................................................................................................13
3.5 加热和加湿模块.............................................................................................................14
3.6 温湿度传感器模块设计.................................................................................................15
3.7 硬件实现效果.................................................................................................................16
4 系统软件设计 ............................................................................................................................19
4.1 下位机系统设计.............................................................................................................19
4.1.1 主控函数.............................................................................................................19
4.1.2 单片机接收蓝牙数据.........................................................................................21
4.1.3 温湿度传感器数据读取.....................................................................................22
4.1.4 单片机数据返回.................................................................................................23
4.2 手机端 APP 设计 ............................................................................................................23
4.2.1 App Inventor2 开发软件介绍.............................................................................24
4.2.2 App 用户界面模块 .............................................................................................24
4.2.3 蓝牙通信模块设计.............................................................................................25
4.2.4 App 运行步骤 .....................................................................................................26
5 系统测试结果和分析.................................................................................................................28
5.1 LED 开关老化测试系统运行测试..................................................................................28
5.2 结果分析 ........................................................................................................................29
6 结 论 ........................................................................................................................................30
参考文献: ....................................................................................................................................31
致谢 ................................................................................................................................................32