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Associate II

Is their any possibilty to use CDC and DFU due to the same USB Port, by switching it by software? And is their any example for it? I tried several things but couldn't find any solution. The configuration at CubeMX Just allows one Class for USB_DEVICE Mode.


Pavel A.
Evangelist III

What do you mean by switching? Do you want only one function at any time, or both simultaneously (a composite device)?


Principal III

dual/composite device :  just an example ->

>> This application provides an example of Azure RTOS USBX stack usage on STM32H747I-DISCO board, it shows how to develop a composite USB Device communication Class "HID" and "CDC_ACM" based application.


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By switching i mean, only one function at any time. The DFU Upload mode then should be started by a defined CDC command.

Thanks for the example, but how can i migrate such a project to my hardware? I tried by creating and comparing and merging a new project for my hardware but without any success. Do you have any tip?

Associate II

I now was able to create a project including CDC_ACM and DFU and the initialization also looks well. The code is similar to the other example with CDC_ACM and HID.

Nevertheless i have problems to run it at the target device STM32H735. In the debug session that function call _tx_thread_schedule(); never returns.

Does anyone have any idea, what I'm doing wrong?

Attached I have the project.

Thanks in advance.