STM32H7S3 - Issue with USB HS CDC (Internal PHY) without VBUS sensing

[Paul-65]

Hi everyone,

I’m reaching out because I’m having trouble setting up a USB HS CDC (Communication Device Class) using the internal PHY, without VBUS sensing.
I use STM32H7S3I8T6.

My program gets stuck in the following loop before timing out:

  /* Core Soft Reset */
  USBx->GRSTCTL |= USB_OTG_GRSTCTL_CSRST;

  do
  {
    count++;

    if (count > HAL_USB_TIMEOUT)
    {
      return HAL_TIMEOUT;
    }

  } while ((USBx->GRSTCTL & USB_OTG_GRSTCTL_CSRST) == USB_OTG_GRSTCTL_CSRST);

  return HAL_OK;
}

Despite searching through various forum topics, I can't seem to get it to work.

Here is my STM32 configuration:

Clock : 

USB Clock : 

Power Regulator :

USB HS Configuration :

USB_DEVICE Configuration :

Here is my configuration.

I would be very grateful for any help you can provide.

Thanks in advance,

Paul

[Gyessine]

Hello @Paul-65 

The behavior you see (code stuck in USB_CoreReset() waiting for USB_OTG_GRSTCTL_CSRST  to clear) is a typical symptom that the USB core is not correctly initialized, often due to a hardware or clock configuration issue. Check this FAQ: Troubleshooting a USB core soft reset stuck. I'd suggest checking your configuration including clock source and PLL settings, clock...
BR
Gyessine

[Paul-65]

Hello,

Yes, I have seen this forum. Despite that, I still can’t get it to work.
I have really checked all the forums that were discussing this issue.

Best regards,
Paul