6.9. Audio V2 Speaker

6.9.1. Overview

This example project shows USB Audio V2 speaker device.

The audio output device is auto-detected when app.yaml declares a board_audio_codec dependency and the board declares both board_audio_codec and a board_codec_* feature. Otherwise DAO is used.
To override the auto-detection, set CONFIG_CODEC before find_package in CMakeLists.txt:
- set(CONFIG_CODEC 1) — force Codec output
- set(CONFIG_CODEC 0) — force DAO output
The Audio Codec type is automatically matched with the hardware based on the board feature (e.g., board_codec_es8389). To specify an audio codec type manually, set the following in CMakeLists.txt: set(CONFIG_CODEC_NAME "wm8960").
The USB High Speed and Full Speed service intervals are configured by EP_INTERVAL_HS and EP_INTERVAL_FS. The packets-per-second value and USB maximum packet size are derived automatically from the configured interval.

Connect a USB port on PC to the PWR DEBUG port on the development board with a USB Type-C cable
Connect a USB port on PC to one of USB port on the development board with a USB Type-C cable
Connect headphone to headphone interface (Audio Codec is the default playback device), or connect speaker to DAO interface if DAO is configured.

Download the program and run. The computer can automatically recognize and install the USB audio driver and enumerate a device with a speaker device.
Select the speaker device as the default player, and the PC will play audio through the headphone (Codec) interface or DAO interface depending on the configuration.