[ladyada] has a freshly-published and amazingly thorough tutorial on passive infrared (PIR) motion sensors. Most often seen in security floodlights and automatic doors, in creative hands these ...

In the microcontroller era today, Arduino ... 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 intrusion ...

PIR motion sensors use infrared light to detect ... You can follow this Random Nerd Tutorials guide to get started with your Arduino motion sensors, but there are plenty of other guides available ...

The code is an Arduino project for the Digispark Attiny85 to turn on a light source when the PIR sensor detects something. Note that after powering the PIR sensor module, it needs about 10 to 60 ...