该程序实现独立按键去控制 LED灯 的亮灭，并讲叙了对按键的处理方法。 独立按键相应的IO口平时为高电平，一旦按键按下，单片机便检测到低电平。-The program implements the independent button to control the LED lights off, and spoke of the right key approach. Independent buttons corresponding IO port usually is high, once