Here is the diagram of my Arduino infrared close proximity sensor ... so it turns on briefly when the signal output pin goes High, providing a visual alert of when the sensor mechanism is detecting ...

A simple way to think of the sensor is a switch; the diagram below explains the ... you can write the code accordingly. PIR Pin “out” connects to Arduino Digital 2 Here is the Arduino code ...

If you are designing your own intelligent “Graden Computer” with an optional digital plant moisture sensor/water pump controller that lights an LED to alert the user when it is time to water a potted ...