Photosensitive resistor module most sensitive to environmental light intensity is generally used to detect the ambient brightness and light intensity.
Module light conditions or light intensity reach the set threshold, DO port output high, when the external ambient light intensity exceeds a set threshold, the module D0 output low;
Digital output D0 directly connected to the MCU, and detect high or low TTL, thereby detecting ambient light intensity changes;
Digital output module DOÂ can directly drive the relay module, which can be composed of a photoelectric switch;
Analog output module AO and AD modules can be connected through the AD converter, you can get a more accurate light intensity value