NUCLEO-H723ZG USB CDC communication not working when using FreeRTOS

[abaril_catalys]

Hello,

I'm trying to communicate with the USB FS CDC on my NUCLEO-H723ZG while using FreeRTOS and the device doesn't enumerate properly. I am using the current up-to-date software pack for STM32H7 -> 1.11.2

I use the CubeMX starting project with the NUCLEO-H723ZG and I only add the USB_OTG_HS as a Full Speed Device.

Then I add the middleware for the CDC using all default parameters.

If I use the project at this point, the USB communication with the virtual comm port works flawlessly. However, it stops working when I add the middleware FreeRTOS with its default parameters

In Windows 11 Device Manager, I am getting the error were the USB descriptor failed (Code 43)

Is there a configuration I am missing ? I would have expected the USB CDC driver to work right out of the box with FreeRTOS at this point...

I have added the .ioc used to generate the projet as well as the main with the code to send an Hello_world message to the virtual com port. The only hardware required is the NUCLEO-H723ZG with 2 USB cables.

[SofLit]

Hello,

Why are you calling CDC_Transmit_HS() from a loop in main 

  while (1)
  {
	  CDC_Transmit_HS(TxBuffer, strlen((const char *)TxBuffer));
	  	HAL_Delay(1000);
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
  }

and in StartDefaultTask() task ?:

void StartDefaultTask(void *argument)
{
  /* init code for USB_DEVICE */
  MX_USB_DEVICE_Init();
  /* USER CODE BEGIN 5 */
  /* Infinite loop */
  for(;;)
  {
	CDC_Transmit_HS(TxBuffer, strlen((const char *)TxBuffer));
    osDelay(1000);
  }
  /* USER CODE END 5 */
}

[abaril_catalys]

Hello SofLit,

The CDC_Transmit_HS I called in the while(1) is a leftover function call when I first started the project without FreeRTOS to check functionality. My bad, I should have removed it when I added FreeRTOS in CubeMX. However, this function is never called since the code only runs the default task after starting FreeRTOS so I doubt it is the problem.

The call to CDC_Transmit_HS in the StartDefaultTask is used to display an "Hello World" every 1 second when I connect a serial terminal. Well if my code worked, that would have been the expected behavior...

Sorry for the confusion this leftover code caused, but I think the root cause of the problem is else where.

Thank you and have a nice day.

[SofLit · Accepted solution]

Hello,

---

However, this function is never called since the code only runs the default task after starting FreeRTOS so I doubt it is the problem.

---

-> I agree. 

Now testing your project and I've reproduced the issue. It seems there is a hardfault with your Task RTOS configuration.

The first thing to thing about in that situation (in baremetal is OK, with RTOS: Hardfault) is the Task stack size.

Increasing the stack size from 128 to 256 makes the hardfault disappears.

Hope it does answer your question.