基于51单片机控制的pwm输出，，占空比可调节，负载位led灯，根据led的亮度强弱可判断pwm占空比的大小-Based on 51 MCU-controlled pwm output, duty cycle can be adjusted, the load position led lights, under the led brightness pwm duty cycle can be judged the strength of the size of the

声明此文件不是原创 qt 做的一个屏幕虚拟键盘 自己做了一个界面，模拟键盘， 将自定义的键盘按键，映射成真实键盘按键 上面还有一些bug, 不过个人觉得可以参考其思想-the project file is not myself the virtual keyboard is made in qt. the ui is user defined ui, map the user buttons to the truth keyboar