Microphone Library for Pico

Capture audio from a microphone on your Raspberry Pi Pico or any RP2040 based board. 🎤

Hardware

• RP2040 board
  • Raspberry Pi Pico
• Microphones
  • Analog
    • Electret Microphone Amplifier - MAX9814 with Auto Gain Control
  • PDM
    • Adafruit PDM MEMS Microphone Breakout

Default Pinout

Analog Microphone

Raspberry Pi Pico / RP2040	Analog Microphone
3.3V	VCC
GND	GND
GPIO 26	OUT

PDM Microphone

Raspberry Pi Pico / RP2040	PDM Microphone
3.3V	VCC
GND	GND
GND	SEL
GPIO 2	DAT
GPIO 3	CLK

GPIO pins are configurable in examples or API.

Examples

See examples folder.

Cloning

git clone https://github.com/ArmDeveloperEcosystem/microphone-library-for-pico.git 

Building

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

export PICO_SDK_PATH=/path/to/pico-sdk

3. Create build dir, run cmake and make:

mkdir build
cd build
cmake -DPICO_BOARD=pico_w -DWIFI_SSID=<wifi_ssid> -DWIFI_PASSWORD=<wifi_password> -DSERVER=<server> -DPORT=<port> ..
make

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

nc -lup <port> > audio.pcm

6. Process

ffmpeg -f s16le -ar 16000 -ac 1 -i audio.pcm audio.wav

License

Apache-2.0 License

Acknowledgements

This project was created on behalf of the Arm Software Developers team, follow them on Twitter: @ArmSoftwareDev and YouTube: Arm Software Developers for more resources!

The OpenPDM2PCM library is used to filter raw PDM data into PCM. The TinyUSB library is used in the usb_microphone example.

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Disclaimer: This is not an official Arm product.