Controlling an LED
The hardware equivalent of hello world
is an LED flash, which is a great test to ensure that everything is working and that you have wired it correctly. To make it a little more interesting, I've suggested using a red, blue, and green (RGB) LED, but feel free to use separate LEDs if that is all you have available.
Getting ready
You will need the following equipment:
- 4 x DuPont female-to-male patch wires
- Mini breadboard (170 tie points) or a larger one
- RGB LED (common cathode)/3 standard LEDs (ideally red, green, and blue)
- Breadboard wire (solid core)
- 3 x 470 ohm resistors
Each of the preceding components shouldn't cost many dollars and can be reused for other projects afterwards. The breadboard is a particularly useful item that allows you to try out your own circuits without needing to solder them:
![](https://static.packt-cdn.com/products/9781788629874/graphics/d3eafc68-8b19-4993-acd3-7af7b979f1b0.png)
Diagrams of an RGB LED, a standard LED, and an RGB circuit
The following diagram shows the breadboard circuitry:
![](https://static.packt-cdn.com/products/9781788629874/graphics/e49061da-b4ab-4110-81e2-a90aa6b4f8c9.png)
The wiring of an RGB LED/standard LEDs connected to the GPIO header