Hello @jding.1
First let me thank you for posting.
To create a USB composite device with CDC and UAC functionality, you can follow these general steps:
1- Select your target microcontroller model (e.g., STM32F479ZITx)
2- Enable the USB_OTG_FS and USB_OTG_HS by navigating to the "Connectivity" tab .

3- In the "Class For FS IP" section, select "Communication Device Class (Virtual Port)" to enable CDC functionality.
In the "Class For HS IP" section, select "Audio Class" to enable UAC functionality.
4- Configure the other settings, such as endpoints, buffer sizes, and callbacks, as needed for your application.
5- Configure the clock settings and other peripheral configurations as per your project requirements.
6- Generate the initialization code using STM32CubeMX and export the project for your chosen toolchain (e.g., STM32CubeIDE).
Thx
Ghofrane
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