STM32U575 ROM bootloader - no USB enumeration on Nucleo-U575Zi-Q

[STayl.7]

I can invoke the ROM bootloader on the STM32U575ZI both by pulling PH3 to 3v3 at boot and I can then connect STM32CubeProgrammer using USART1 PA9, PA10 as described in AN2606. However the STM32U5 does not enumerate via the USB-C connector on the Nucleo board.

I have verified that VDDUSB is supplied (DVM measures 3v3 on SB30).

Does anyone have any ideas why the ROM bootloader will not enumerate with my PC ? Thanks.

I should add that the STM32U575 Nucleo enumerates with my PC just fine via the USB-C connector when my application is running on it - so I don't think that there is a fundamental electrical problem.

[STayl.7 · Accepted solution]

Quick update on this. It turns out that the Nucleo-U575Zi-Q I was given to do the evaluation were given to our CEO by ST (not purchased from ST / Digikey as I had assumed) and have pre-production silicon with a known issue in USB/DFU.

Our FAE confirmed this to be the case and confirmed that the USB bootloader enumeration works fine on the production Nucleo-U575Zi-Q.

So false alarm - it never occurred to me that I might have been given pre-production silicon to do the bring-up.

[Billy OWEN]

Hi @Community member​ 

The forum moderator had marked your post as needing a little more investigation and direct support. An online support case has been created on your behalf, please stand by for just a moment and you will hear from us.

If anyone else has similar types of questions, please feel free to open a support case directly at http://my.st.com/ols

Regards,

Billy