The Arduino Sketch (code) uses the external interrupt (int 0) on Arduino’s digital pin 2 (D2). This is used to read the output pulses coming from the water flow sensor. When Arduino detects the pulse, ...

Arduino pulse sensors have a small infrared ... You can usually find a guide to help you to use your sensor, but you may have to be creative to make the code work for you. You can get your hands ...

In this particular case, it’s a DIY USB polygraph-like machine by [Juangg] using an Arduino and sensors on ... complete with 3D printed enclosure and sensor elements. The polygraph may have ...