2. Case 01: Traffic Lights

2.1. Introduction

To make a traffic lights system controlled by the micro:bit.

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2.2. Quick Start


Materials Required


Nezha expansion board × 1

micro:bit × 1

LED-red × 1

LED-green × 1

LED-yellow × 1

RJ11 wires × 3

Bricks details

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Connection Diagram


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

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Assembly


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Video reference:https://youtu.be/TmsDDWLcgcs

2.3. 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:

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Reference

Link:https://makecode.microbit.org/_M6RiKA642WPP

You may also download it directly below:

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Result

  • The red LED lights on for 5 seconds and then lights off; the yellow LED lights on for 2 seconds and off then; the green LED lights on for 5 seconds and off then.