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, ...

Since the interrupt signal comes from outside the Arduino it is called as external interrupt. Arduino Uno R3 has two external interrupts: int.0 (pin 2) and int.1 (pin 3). While connecting a RT to ...

When the blade passes in between then, the receiver shuts off a transistor connected to one of the Arduino’s external interrupt pins. He shows how to use this interrupt to measure the amount of ...