STM32H753ZI Nucleo board with USB_OTG_FS communication

[HMsDobby2]

I'm using the STM32H753ZI Nucleo board with USB_OTG_FS communication,

and I have enabled VBUS_SENSING.

I would like to detect when the physical connection is lost,

but I am not sure how to do it.

Could you kindly provide any reference materials or guidance on the best approach?

[FBL · Accepted solution]

Hi @HMsDobby2 

Which stack are you using? If it is USBX x-cube-azrtos-h7, in order to implement detection of USB cable removal, you can add the following in app_usbx_device.c file.

static UINT USBD_ChangeFunction(ULONG Device_State)
{
 UINT status = UX_SUCCESS;
 
/* USER CODE BEGIN USBD_ChangeFunction0 */
 
/* USER CODE END USBD_ChangeFunction0 */
 
switch (Device_State)
{
  case UX_DEVICE_ATTACHED:
 
    /* USER CODE BEGIN UX_DEVICE_ATTACHED */
 
    /* USER CODE END UX_DEVICE_ATTACHED */
 
    break;
 
  case UX_DEVICE_REMOVED:
 
    /* USER CODE BEGIN UX_DEVICE_REMOVED */
 
    /* USER CODE END UX_DEVICE_REMOVED */
 
    break;
 
  case UX_DCD_STM32_DEVICE_CONNECTED:
 
    /* USER CODE BEGIN UX_DCD_STM32_DEVICE_CONNECTED */
 
    /* USER CODE END UX_DCD_STM32_DEVICE_CONNECTED */
 
    break;
 
  case UX_DCD_STM32_DEVICE_DISCONNECTED:
 
    /* USER CODE BEGIN UX_DCD_STM32_DEVICE_DISCONNECTED */
 
      HAL_PCD_DisconnectCallback(&hpcd_USB_OTG_HS);
 
      /* USER CODE END UX_DCD_STM32_DEVICE_DISCONNECTED */
 
    break;
 
  case UX_DCD_STM32_DEVICE_SUSPENDED:
 
    /* USER CODE BEGIN UX_DCD_STM32_DEVICE_SUSPENDED */
 
    /* USER CODE END UX_DCD_STM32_DEVICE_SUSPENDED */
 
    break;
 
  case UX_DCD_STM32_DEVICE_RESUMED:
 
    /* USER CODE BEGIN UX_DCD_STM32_DEVICE_RESUMED */
 
    /* USER CODE END UX_DCD_STM32_DEVICE_RESUMED */
 
    break;
 
  case UX_DCD_STM32_SOF_RECEIVED:
 
    /* USER CODE BEGIN UX_DCD_STM32_SOF_RECEIVED */
 
    /* USER CODE END UX_DCD_STM32_SOF_RECEIVED */
 
    break;
 
  default:
 
    /* USER CODE BEGIN DEFAULT */
 
    /* USER CODE END DEFAULT */
 
    break;
 
}

And update this call

/* Install the device portion of USBX */
if (ux_device_stack_initialize(device_framework_high_speed,
device_framework_hs_length,
device_framework_full_speed,
device_framework_fs_length,
string_framework,
string_framework_length,
language_id_framework,
language_id_framework_length,
USBD_ChangeFunction) != UX_SUCCESS)