STM32 Composite Class USB Device Application (MSC + HID) based on the STM32U5

Overview

This project implements a composite USB device combining two classes:

• Mass Storage Class (MSC): allows using internal SRAM as USB storage.
• Human Interface Device (HID): emulates a user input device (mouse).

Application Description

This application demonstrates how to implement a USB device combining Mass Storage Class (MSC) and Human Interface Device (HID) functionalities on the STM32U545RE microcontroller.

It showcases the use of the STM32 USB Full-Speed Device peripheral to create a composite USB device that is simultaneously recognized by the host PC as both a removable storage drive and a HID mouse.

The NUCLEO-U545RE-Q board is used to illustrate this application, leveraging internal SRAM for mass storage and emulating a simple mouse through HID reports.

Objectives

This application aims to show how to:

• Create a composite USB device with MSC and HID interfaces.
• Provide USB mass storage functionality using internal SRAM.
• Emulate a USB HID mouse sending periodic movement reports.

Key Features

This application showcases the following features:

• USB Composite Stack: supports multiple interfaces.
• MSC Interface:
  • Implements SCSI commands for read/write.
  • Uses internal SRAM as storage medium.
• HID Interface:
  • Emulates a standard USB mouse.
  • Sends HID reports via interrupt endpoints.

Hardware and Software environment

• This application runs on STM32U545RE devices.
• This application has been tested with STMicroelectronics NUCLEO-U545RE-Q boards and can be easily tailored to any other supported device and development board.
• This application is developed in STM32CubeIDE v1.18.0.

How to use it ?

• Open and import the project into STM32CubeIDE v1.18.0 or newer.
• Rebuild all files and load your image into target memory.
• Run the application.

Additional resources

Please refer to this article for more details.

Contributing and support request

Please refer to the CONTRIBUTING.md guide.