# Gamma-Omega Original

## Quick Links
- [3D Printable Case](../cases/)
- [PCB](pcb/) 
- [Ergogen Configuration](ergogen/README.md) 
- Firmwares
    - [QMK/VIAL Implementation](firmwares/QMK/gamma_omega/)
    - [ZMK Firmware](https://github.com/unspecworks/zmk-config-gamma-omega)
- [Build Guide](BUILD_GUIDE.md)

## Photos

<img alt="The original Gamma Omega keyboard" src="../images/gamma.jpg" height="200" /> <img alt="Two PCBs inside the original Gammma Omega" src="../images/gamma2.jpg" height="200" />

## PCB design

This uses two identical reversible PCBs for the two halves of the keyboard, joined at the RP2040 controller.
This means some pins cannot be used as there isn't a matching pin on the other side,
for example GP0 and GP1 are opposite voltage pins.

This diagram sketches the [GPIO usage](../images/black-raspberry-pi-pico-pins.png)
(red and blue coloring following the convention for the two sides of the PCB).

The design assumes a specific Raspberry Pi Pico variant with GPIOs on pins 35 and 37 (GP29 and GP23),
which are not available on the original board design.
However the pairs GP13/18, GP14/17, and GP15/16 at the bottom of the board are unused,
so in theory the PCB could use those instead for compatibility with the original pin allocation.