The tap sensor module KY-031 and the digital 13 interface comes with an LED to build a simple circuit to make a tap flasher. Use the built-in LED of the digital 13 interface to connect the tap sensor to the digital 3 interface. When the tap sensor senses a tap signal, the LED flashes and glows. The tap sensor can monitor whether the object is collided. The percussion sensor is composed of a plexiglass shell and an internal spring, which can feel the vibration of small amplitude and is more sensitive than ordinary vibration sensors. Therefore, the knock sensor module can be used to make strobes, monitor knocks, and so on.

Module wiring
1. GND connects the negative pole of the power supply (the board shows -)
2. Connect VCC to the positive pole of the power supply 3.3-5V
3. DO TTL switch signal output (the board shows S)