Here is an ultra simple Arduino Night Alarm project ... at its sensor input port. As indicated, our system requires a “Logic High (H)” level input to wake up. The best sensor you can use to detect an ...

When something passes in front of a PIR sensor ... to Arduino gnd Other side of 10K Resistor connects to PIR Pin “Alarm” PIR Pin “Alarm” connects to Arduino Digital 2 The code for the ...