Overview

 This short cut keyboard uses an Arduino compatible to create key combo sequences. It can have up to 4 keys/buttons.

The code has key combinations for Java IDE shortcuts, but is also open source. So the code can be updated for keyboard shortcuts for any program or operating system.

Bill of Materials

Below is a list of parts and materials used in this project  

• 3D Printer Filament - to print the enclosure
• Adafruit Trinket Mini - This is the Arduino compatible that sends the keyboard shortcuts to the PC over USB.
• Switches/Buttons - this project has mounting plates for a couple of switch types. Choose one of the following key types and the matching mounting plate (see the 3D Printing section).
  
  
  • Adafruit 1009.
  • Cherry MX

Wiring

Below is the wiring diagram for this project  

Software

 The C++ source code for this project is open source and FIX THIS -->>> available on Github. <<<-- FIX THIS

The OpenSCAD source code for the 3D models is also open source and available on Github.

3D Printing

The STL files are on Thingiverse.  

Print the base and the matching mounting plate for the switches.

Assembly & Usage

Place the mounting plate in its cutout on the enclosure base. Then place the Trinket Mini on the 4 mounting studs inside the enclosure. This gives an idea of the length of the wires needed to connect the botttons to the Trinket Mini.

 Solder wires to the buttons, making sure the wires reach the Trinket Mini

I decided to put female headers on the Trinket Mini to connect the wires leading to the button. The wires can be soldered directly to the Trinket if a more permanent setup is required/wanted.

Resources

• Originally I was going to use CircuitPython, but then I found this guide that uses C++ with Trinket.