Connect the 5V power supply, power indicator light, sensor board does not drop when, do output is high, the switch lights off, dripping a drop of water, do output is low, the switch indicator light,brush above water droplets, has returned to the output high state. . . AO analog output can be connected to the controller detects AD mouth drops of rain in the above size.Do TTL digital outputs can also be connected to the controller detects whether there is rain.