18. Case 17: Alarm Device

18.1. Introduction

Build an alarm device with the micro:bit.

../../_images/case_17_01.png

18.2. Quick to Start


Materials


Nezha expansion board × 1

micro:bit × 1

LED-red × 1

RJ11 wires × 1

Bricks × n

../../_images/case_17_02.png

Bricks details


../../_images/Bricks_case_17.png

Connection Diagram


  • Connect the red LED to the J1 port on Nezha expansion board.

../../_images/case_17_03.png

Bricks Build-up


  • Build a device as the pictures indicate:

../../_images/case_17_04.png

../../_images/case_17_05.png

../../_images/case_17_06.png

Video link:https://youtu.be/bYN6-6PskHQ

18.3. MakeCode Programming


Step 1


Click “Advanced” in the MakeCode drawer to see more choices.

../../_images/case_01_10.png

We need to add a package for programming. Click “Extensions” in the bottom of the drawer and search with “PlanetX” in the dialogue box to download it.

../../_images/case_01_11.png

Note: If you met a tip indicating that the codebase will be deleted due to incompatibility, you may continue as the tips say or build a new project in the menu.

Step 2


Programme as the picture shows:

../../_images/case_17_15.png

Result

  • Press button A to alarm and the red LED flashes; press it again to stop the alarming and the LED turns off.