# Make an RGB LED Blink with micro:bit

Difficulty
Easy
Steps
11

You might have already tried your hands at making a two colour LED module blink with the micro:bit, but have you tried using an RGB LED module?

In this guide, you will learn to make an RGB LED blink and change to a variety of colours.

Complete this guide to learn the basics of programming an RGB LED!

If you're using the Micro:bit Advent Calendar, you'll need the contents of the bags labelled 2 and 25.

Parts Used in This Guide

## Step 1  The Module

Let's take a look a closer look at the RGB LED Module before we begin!

There are four pins:

• RED (R)
• GREEN (G)
• BLUE (B)
• GND: In electronics, we define a point in a circuit to be a kind of zero volts or 0V reference point, on which to base all other voltage measurements. This point is called ground or GND.
• Note: Voltage is the difference in electric potential between two points. As it is difficult to talk about voltage without a reference point, we need another point to compare it to.

As you might guess, this module is capable of emitting red, green, blue as well as a variety of colours based on how they are combined. This module has on-board resistors, so external resistors are not required here.

Let's start making the circuit!

## Step 3  Insert the Micro:bit into the Breakout board

Insert the micro:bit into the breakout board . Make sure that the micro:bit is inserted in the right orientation, with the buttons facing inward as shown.

## Step 8  Start Makecode Editor

Now let's program it with the Makecode Editor

1. Click on 'Projects' button
2. Click on 'New Project'

## Step 9  The code

1. Drag a "forever" block from the Basic section of the editor's panel
2. Click on Pins button on the editor panel, drag a "digital write pin ... to ... " block
3. Click on Basic button on editor panel and drag a "pause (ms) ... " block
4. Change  "digital write pin ... to ..." block to "digital write pin P0 to 1"
5. Change 'pause (ms) ... " block into "pause (ms) 500"
6. Repeat steps 2 and 3
7. Change  "digital write pin ... to ..." block to "digital write pin P0 to 0"
8. Change 'pause (ms) ... " block into "pause (ms) 500"
9. Repeat steps 2 and 3 again
10. Change  "digital write pin ... to ..." block to "digital write pin P1 to 1"
11. Change 'pause (ms) ... " block into "pause (ms) 500"
12. Repeat steps 2 and 3 again
13. Change  "digital write pin ... to ..." block to "digital write pin P1 to 0"
14. Change 'pause (ms) ... " block into "pause (ms) 500"
15. Repeat steps 2 and 3 once again
16. By now you might have gotten the hang of it! Change it for P2 as shown in the diagram.

## Step 10  Turn on more than one colour at a time!

Did you know? You can turn on more than one of the colours at the same time. When this happens, the overall colour of the LED will be a blend of the RGB LED colours. Let's try that out and find out what colours you get for each combination!

1. First Pin 0 is turned on which lights up the LED in RED.
2. Then 500 milliseconds passes before Pin 1 is turned on, where the LED is now shining in RED+GREEN. After you upload the code to the micro:bit, you should see a bright green with a hint of red emitting from the LED.
3. 500 milliseconds passes again. Then with Pin 0 still turned on, Pin 2 is turned on which has the LED shining RED+BLUE. After you upload the code to the micro:bit, you should see a bright purple colour emitting from the LED.

Give it a try, test out these combinations yourself:

• RED + GREEN
• RED + BLUE
• GREEN + BLUE
• RED + GREEN + BLUE

## Step 11  Upload the code to micro:bit

1. Connect a microUSB cable to the micro USB port of the micro:bit.
2. Then connect the other end of the cable to your computer or laptop's USB port.