circuit design - How do I build a USB joystick/button encoder board without using an Arduino or Teensy

I am making a macro keys button box and need something to convert the buttons into keyboard inputs on a PC, such as a shortcut key in a game.

Previously I have used an Arduino Pro Micro, although in order to make it more professional, I am wanting to make a custom PCB with terminals for the buttons to easily connect to. I then want to make a computer app that easily allows me to change the buttons. I am considering using a Atmega32U4 chip to control everything and then simply have terminals for buttons which go to ground and a pin on the chip.

• Is this a good way to do this and how would I actually program it?


• Would it be as simple as uploading the Arduino firmware and then uploading my own sketch to it, or is it more complicated than this?

I basically want to make a USB Joystick Encoder which I can program the buttons with my own app. Although, rather then purchasing a USB Joystick Encoder, I want to make the PCB and solder on the parts myself.