2.3 Service BellΒΆ

For this project we used a microswitch and an active buzzer to create a service bell. Tap the switch and the buzzer makes a sound.

Micro Switch is also a 3-pin device, the sequence of the 3 pins are C (common pin), NO (normally open) and NC (normally closed).

When the micro switch is not pressed, 1 (C) and 3 (NC) are connected together, when pressed 1 (C) and 2 (NO) are connected together.




  • By default, pins 1 and 3 of the Micro Switch are connected together and GP14 is low. When the Micro Switch is pressed, GP14 is high.

  • GP15 outputs high to make the buzzer sound.



  • You can refer to the image below to write code by dragging and dropping.

  • Import 2.3_service_bell.png from the path of euler-kit\piper. For detailed tutorials, please refer to Import the Code.


After connecting Pico, click the Start button and the code starts to run. Tap the switch and the buzzer makes a sound.


This project code is exactly the same as the previous project 2.2 Button.