Knife Switch with NeoPixels

Create a Cardboard Knife Switch by following the steps in this guide: Switch - Cardboard Knife Switch

Alternatively, you could create this same project using a different variation of the cardboard switch:

Cardboard Push Button

Cardboard Slide Switch

When connecting Crazy Circuits projects to paper circuits-style projects we usually stick everything down to a piece of scrap cardboard.

Attach the Knife Switch and a LEGO baseplate to the cardboard using regular tape.

The NeoPixel Strip can be connected to some LEGO technic parts and then taped down to the cardboard base to hold it in place.

Use Maker Tape to connect one side of the Knife Switch to Pin 0 and the other side of the Knife Switch to ground.

We also mixed 1/4" and 1/8" Maker Tape for our connections, but if you only have 1/8" Maker Tape that should work just fine.

The magical thing about these “Individually Addressable” LEDs is that you don’t have to connect each LED to an individual pin on your micro:bit, you just need one signal wire along with power (Positive and Negative) to light things up.

So let's get connected! If you turn the NeoPixel Strip over you'll see labels for the three pins. You should see IN, VCC, and GND.

Use the Crazy Circuits Ribbon Cable to connect the NeoPixel Strip to the Bit Board.

The end with S1, +, and - can plug directly into the Pin 13 row (make sure S1 goes into 13) and the other end should plug into the NeoPixel Strip as shown.

We only need three wires for the NeoPixel Strip so you can leave S2 (the Orange wire) unconnected.

Connect the Bit Board to the LEGO baseplate making sure that the Maker Tape paths connect to Pin 0 and Ground.

In the next step we're going to provide a link to the code for this project, but first let's look at the NeoPixel Extension for MakeCode.

The Extension has the basic blocks you'll need to set up the NeoPixel Addressable RGB LEDs and to control them with a micro:bit, and the Bit Board makes it very easy to connect things!

If you've never used a micro:bit before you'll want to check out this guide: Bit Board V2 Setup and Use

We're going to load the following code for our Knife Switch NeoPixel program: https://makecode.microbit.org/S58486-627...

Here's the result of adding our knife switch to a Bit Board project.

Now we can throw the big switch to get those NeoPixels going.

What ideas can you come up with to connect a knife switch to a Crazy Circuits project?