使用4路AD中的1路检测外部模拟量输入，显示0-255数值DA输出电压用LED显示，主要用于检测环境光线，光线强，则灯亮度小，以保证整体光强稳定在一个范围，这种思路和用法主要用于自动调光，可以根据环境亮度自动调节，从而达到节能最大化-Detecting external analog input, 1 channel 4-channel AD 0-255 numerical DA output voltage LED display is mainly used to detect ambient light, light, lamp brightness, in order to ensure that the overall intensity stabilized at a range , this line of thinking and usage is mainly used for automatic dimming can be adjusted automatically according to the ambient brightness, so as to achieve the energy saving maximize