Easy DIY 3 Button Macro Pad

Used Parts

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• Waveshare RP2040-Zero
• Gateron Switches
• DSA Keycaps
• M3x5x4.2 Brass Inserts
• M3x6mm Screws

Printing the housing

There are three types of files: STL, STEP and FCStd.
PrusaSlicer can handle STEP or STL so chose what you prefer. The FCStd file is the source model. It was modeled in FreeCad (RealThunder Fork).

The model is designed with 0.2mm layer height and a 0.4mm nozzle in mind. Different settings might work but were not tested. Ironing the top surface worked well for me. Adaptive layers for the top rounding head a good effect. This model needs no support for printing.

There are two different files for the top, one designed for threaded inserts and one for M3 straight into the plastic. If you chose to use Inserts, add them after printing before soldering.

 Getting CircuitPython onto the RP2040-Zero

• Download the CircuitPython Image: https://circuitpython.org/board/waveshare_rp2040_zero/ 
• Hold down the Boot button and connect it via USB to the PC.
• A new drive should appear, let go of the boot button and copy the UF2 file onto this drive.
• The drive disappears and a drive with name “CIRCUITPYTHON” emerges.
• The board is prepared.

Soldering

If the following instructions are unclear have a look at the video ;)

• Put your switches of choice into the housing.
• One pin of every switch has to be connected to GND, you can just connect them all together and then to GND.
• Solder the other pin of the buttons to pin 10, 11 and 12 on the RP2040-Zero.
• That's it, soldering done. Congratulations!

Code

There are three things to copy (see code.zip):

• lib folder: Contains libraries needed for the code just copy the hole folder to the drive and replace the existing lib folder
• code.py: This contains the main code. Here you can edit your macros (see the video). Copy it to the main directory of the drive (replace existing)
• boot.py: When you copy this file to the drive, the next time you connect the macro pad the drive will not appear! Unless you press down the button connected to pin 10 while connecting it via USB! You don't need this file if you don't mind the drive.

Final assembly

It's always a good idea to test things first before screwing them together, so do that ;)
Pop the board into his place (USB down). This is designed to be snap fit so you should not need anything else to hold it in place. Now add the M3x6mm screws and you are done!

If you have any questions, just ask. Here or under the YouTube video. (It is likely that you'll get a faster answer if you comment under the video since I get a notification if you do so)