The PIR Motion Sensor, or Passive Infrared Sensor, is a sensor that takes a snapshot
of the room and sets the alarm
pin to LOW
if it detects changes in heat.
Since this sensor is an open collector,
it needs a pull-up resistor on the alarm pin, which allows multiple motion sensors to
be connected on a single input pin. If motion is detected in this
demo, it will output "Motion Detected" on the console and will turn on the LED.
- Connect the '+' pin from the sensor to 'P9_5' of the BeagleBoard in series with a 10kohm resistor.
- Connect the '-' pin from the sensor to 'P9_1' of the BeagleBoard.
- Connect the 'AL' pin from the sensor to 'P8_19' of the BeagleBoard in series with a 10kohm resistor.
- Connect the LED with a 470ohm resistor
- Click "Run" on the code. Every 2.5 seconds, the console will tell you if there was motion detected. If there was motion detected, the LED will also turn on.