RNNoise Examples for Pico 2

Example project to demonstrate the RNNoise audio noise suppression algorithm running on a Raspberry Pi Pico 2 board, using the RP2350's Cortex-M33 processor.

Hardware

• RP2350 board
  • Raspberry Pi Pico 2
• Microphones
  • PDM
    • Adafruit PDM MEMS Microphone Breakout

Default Pinout

PDM Microphone

Raspberry Pi Pico 2 / RP2350	PDM Microphone
3.3V	VCC
GND	GND
GND	SEL
GPIO 21	DAT
GPIO 20	CLK

Note: The GPIO pins for the microphone are configurable in the source code.

Noise Suppression Switch

To control the noise suppression feature, use GPIO18:

• RNNoise Enabled (Default): Leave GPIO18 floating or pull it high.
• RNNoise Disabled (Bypass): Connect GPIO18 to GND. This is useful for quick A/B testing or if you want to use the microphone without filtering.

Examples

See examples folder.

Cloning

git clone https://github.com/ArmDeveloperEcosystem/rnnoise-examples-for-pico-2.git

Building

1. Set up the Pico C/C++ SDK
2. Set PICO_SDK_PATH

export PICO_SDK_PATH=/path/to/pico-sdk

3. Set Correct TinyUSB Version

This is a critical step. This project is tested and confirmed to work with TinyUSB version 0.17.0. Later versions (like 0.18.0) have API changes that break the build.

4. Create build dir, run cmake and make:

mkdir build
cd build
cmake .. -DPICO_BOARD=pico2
make

5. Copy example .uf2 to Pico when in BOOT mode.

Acknowledgements

This project would not be possible without the incredible work from the open-source community.

• TinyUSB: For the robust and easy-to-use USB device stack.
• RNNoise: For the high-quality, low-footprint noise suppression library.
• ArmDeveloperEcosystem/microphone-library-for-pico: For the excellent PDM microphone driver and base examples.

License

BSD-3-Clause license

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Disclaimer: This is not an official Arm product.