STM32N6570-DK USB UVC Not Detected – Possible USBPD/UCPD Dependency?

[saikumar]

Hello,

I'm working on implementing USB UVC on the STM32N6570-DK board. I generated a project using STM32CubeMX only for FSBL and added the following files manually from the ST USBX example project

1 . ux_device_video.c and .h
2 . ux_device_descriptors .c and .h
3 . app_usbx_device .c and .h
4 . app_azure_rtos.c and .h

All files were taken from this example:

https://github.com/STMicroelectronics/STM32CubeN6/tree/main/Projects/STM32N6570-DK/Applications/USBX/Ux_Device_Video/Appli 

However, I did not use USBPD/UCPD in my CubeMX configuration. The ST example uses both USBPD and UCPD and also includes a separate FSBL and Application.

Issue:

When I flash the my project to the STM32N6570-DK board, the USB device is not enumerating as a UVC device it does not appear in the Windows Device Manager at all.

I previously tested a similar setup on an STM32U5 device, and it worked — the UVC device was properly enumerated.

Questions:

1. Is UCPD/USBPD required for USB UVC to work on the STM32N6570-DK board?

2. Could this be the reason the USB is not being detected?

3. Could ST provide a   .ioc   file for the UX_Device_Video example project  for reference?

Any help or clarification would be greatly appreciated!

Thank you

[FBL]

Dear @saikumar 

First, did you follow the README file and flash the provided example? Does it work as-is, or not? Without regenerating the code using CubeMX?

[saikumar]

Hello ,  mr @FBL 

Yes, I followed the README instructions and flashed the provided example without regenerating any code. It worked correctly__the UVC device was properly enumerated and appear in  Windows Device Manager, and I was able to preview the video output using the Windows Camera app.

However, when I tried to generate the project using STM32CubeMX (for FSBL only) it is not working. please check the source code and .ioc provided above .

Thank you,

[FBL]

Hi @saikumar

Currently, latest CubeMX v6.14.1 does not support USB code generation for STM32N6 in USB applications. You should refer to example provided in CubeN6 as reference.

[saikumar]

Hello, mr @FBL 

Thank you for the response.

As per my understanding, currently only STM32CubeMX versions 6.14.0 and 6.14.1 support the STM32N6 series. I have tested USB configuration using both versions, but unfortunately, the issue remains the same.

Also, I would appreciate clarification on the following:

• Is it mandatory to use UCPD and USBPD configuration for USB Device classes like UVC or CDC to work properly?

• If UCPD/USBPD is not required, then could you please confirm whether my CubeMX USB configuration (as shared above in this discussion) is correct or missing any required settings?

Thank you in advance for your guidance.

[FBL · Accepted solution]

Hi @saikumar 

I assume in case, you don't use UCPD peripheral, you need to make some hardware change in schematics to pull down CC lines with 5.1KOhms and reconfigure TCPP port to type C only. Otherwise, use the second USB controller as implemented type C only.