The multicolour LED or RGB LED (Red Green Blue Light Emitting Diode) (WS2821B) is used to alert the user with light.

Examples:

1. To show when the soil is too wet or too dry or hydrated enough.
2. Smart Traffic Light: distance sensor detects more traffic on one side and changes LED colours to let traffic move.

Pin:

• D9 pin on the SNT Kit PCB. (the multicolour LED is on the PCB and does not need other wire connections)

Colours:

This RGB colour wheel can be used to get more colours.

• Red + Green = Yellow
• Green + Blue = Cyan
• Blue + Red = Purple
• Red + Green + Blue = White.

Library:

• FastLed from the Arduino Library Manager in Arduino IDE or download from here.

Code:

• Click here for the code to test your multicolour LED