WavePhoenix 0.9.0 : An Open-Source Implementation of Nintendo’s WaveBird Protocol with Silicon Labs Wireless Gecko SoC - chép game pc , ps2, ps3, ps4, ps5, switch...

26/04/2025 3 min read

The WaveBird , the Nintendo GameCube wireless controller, remains one of the most popular input devices in video game history. Wireless, with exceptional battery life and an ergonomic design, it revolutionized the concept of wireless controllers, abandoning infrared in favor of radio frequency (RF) for a stable and lag-free connection.

With production discontinued for over a decade, original receivers are becoming increasingly rare and expensive. For this reason, WavePhoenix was developed , an open-source implementation of the WaveBird protocol, based on modern Silicon Labs Wireless Gecko SoCs .

Technical Features

Modular Firmware

WavePhoenix is structured into well-defined components:

libwavebird: Implements WaveBird protocol (packet encoding/decoding, CRC, DSSS).
libsi: Handles communication with GameCube/Wii via the SI bus .
receiver: Reference firmware for a working WaveBird receiver.
bootloader: Allows firmware updates via Bluetooth.

Accessible Hardware

The project includes files to build a low-cost miniaturized receiver :

PCB designed in KiCad (compatible with Gerber production).
3D printable case for compact and robust design.
Based on RF-BM-BG22C3 (EFR32BG22) module, which is cheap and easy to find.

Reverse Engineering of the WaveBird Protocol

DSSS and Radio Modulation

The WaveBird uses a form of Direct Sequence Spread Spectrum (DSSS) with 15 chips per bit , an unusual but effective choice for reducing interference. After reviewing Sam Edwards’ documentation and conducting practical tests, I identified the correct parameters:

Center frequency : 2.485 GHz (ISM band).
Data rate : ~250 packets per second.
BCH(31,21) encoding for error correction.

Package Structure

Each package contains:

Preamble (synchronization).
Interleaved data (reduction of burst errors).
CRC-8 for integrity.

Messages include:

Input status (buttons, analog sticks).
“Original” messages (stick calibration at boot).

Challenges and Solutions

1. Find a Compatible SoC

After examining dozens of datasheets, I discovered that only the Silicon Labs EFR32FG1/EFR32BG22 natively support 15-chip DSSS, a requirement for demodulating the signal in hardware.

2. Real-time decoding

To avoid lag, I took advantage of the advanced peripherals of the SoC:

Timer + DMA to sample the SI bus at 225 kHz.
USART to generate timed responses.

3. Reception Optimization

The original receiver maintains reliability >10m distance . After months of tuning:

Sensitivity improved from 60 to 230+ packets/second at 5m.
Virtual pairing via button (automatic scanning of 16 channels).

How to Build a Receiver

Necessary Material

PCB (orderable via Gerber).
RF-BM-BG22C3 Module .
Passive components (resistors, capacitors).
JST connector for GameCube.

Firmware

Program the module via Segger J-Link .
The bootloader allows OTA updates via Bluetooth.

Detailed instructions: GitHub Wiki .

Future Implementations

Transmitter Firmware : Turn a wired controller into a wireless one.
N64 Support : SI bus is similar, minor changes needed.
USB HID Dongle : Using WaveBird on PC/Dolphin/RetroArch.

Thanks

Sam Edwards for the reverse engineering documentation.
Jeff Longo for GameCube protocol analysis.
BitBuilt community for technical support.

Conclusions

WavePhoenix proves that, with the right skills and modern hardware, it is possible to resurrect obsolete technologies while maintaining their reliability. The project is open-source: contributions and forks are welcome!

Download and source code : GitHub – WavePhoeni