CubeMx clock resolver chooses the wrong USB clock frequency

[TechGuyMike]

I'm using CubeIDE 1.15 with CubeMx plugin 6.11 to develop code for STM32H745.

The clock resolve chooses 64MHz for USB:

whereas the correct USB clock frequency is 48MHz:

I would expect the clock configuration GUI to flag this issue for me and set up the correct frequency of 48MHz for USB when running the clock resolver.

 

Just in case this is relevant, this is what my USB setup looks like:

 

[STTwo-32]

Hello @TechGuyMike 

I've tried to reproduce that issue but each time the USB Clock is generated correctly:

 

 

Can you add more details (are you starting your project from an MCU or a board, what are the Steps to reproduce ,...).

Best Regards.

STTwo-32

[TechGuyMike]

Sure, here's a repro scenario:

Start with STM32CubeIDE 1.15 and CubeMx plugin 6.11.0.

Choose MCU STM32H745IIK6 when creating a new project.

Agree to apply the default configuration of the MPU.

Enable support for HF/LF crystal oscillators and enable USB FS device mode:

 

Enable HSE and set the input frequency to 16 MHz:

 

Choose PLLCLK and set MCU core frequency to 320 MHz:

Once the clock tree is automatically updated, "to USB" frequency is automatically set to 64 MHz:

 

[FBL]

Hello @TechGuyMike 

I confirm CubeMX should not exceed the required value for the controller as detailed in datasheet. Internal PHY clock is running at 48MHz whatever the speed is. An internal ticket 179358 is submitted to dedicated team.

[Jacob WOODRUFF]

Hi All,

 

This post has been escalated to the ST Online Support Team for additional assistance. We'll contact you directly.

 

Regards,

Jake

ST Support