10. Case 09: Invading Detection Device

10.1. Introduction

To make an invading detection device with the micro:bit.

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10.2. Quick Start

Materials Required

Nezha expansion board × 1

micro:bit × 1

LED-green × 1

LED-red × 1

Sonar:bit × 1

RJ11 wires × 3

Bricks details

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Connection Diagram

  • Connect the sonar:bit to J1, red LED to J2 and green LED to J3 on the Nezha expansion board as the picture shows.

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Assembly

  • Build a device as the picture shows:

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Video Reference: https://youtu.be/jw9_wlNIiHw

10.3. MakeCode Programming

Step 1

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

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For programming, we need to add a package: click “Extensions” at the bottom of the MakeCode drawer and search with “PlanetX” in the dialogue box to download it.

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Notice: If you met a tip indicating that some codebases would be deleted due to incompatibility, you may continue as the tips say or create a new project in the menu.

Step 2

Code as below:

../../_images/case_09_08.png

Reference

Link：https://makecode.microbit.org/_2zrE6AKRHbqW

You may also download it directly below:

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Result

  • While the sonar:bit detects the object, the red LED lights up and the buzzer alarms.