STM32H723: Window WatchDog (WWDG)

[jowakar122]

I am using STM32H723 and have implemented WWDG. Below is my configuration: 

Are there possibility that when the system resets due to watchdog it would not trigger its ISR. 

[LCE]

Not sure, never used WWDG, but why not 

NVIC_DisableIRQ(WWDG_IRQn);

?

[TDK]

The EWI interrupt will function as intended.

There exist scenarios in which it will not be called. For example, if interrupts are disabled, it won't be called.

[jowakar122]

@TDK I am not disabling its interrupts. Even if I disable the interrupt it will still reset but without triggering its ISR

[LCE]

> Are there possibility that when the system resets due to watchdog it would not trigger its ISR.

...

> Even if I disable the interrupt it will still reset but without triggering its ISR

Isn't that what you asked for? Scratch head...

[TDK]

Show your code.

[jowakar122]

@TDK I am using FREERTOS and have a 2 tasks running. Task A looks out for the messages coming from the TCP server and acts accordingly. For OTA when the TCP client (my module) I do this:

				case BLE_Command_Request_OTA 		:
													if(BLE_Request_OTA() != 0)
													{
														char str[50];
														uint16_t count = 0;

														HAL_TIM_Base_Stop(&htim3);
														HAL_TIM_Base_Stop(&htim15);
														HAL_TIM_Base_Stop(&htim16);
														HAL_TIM_Base_Stop(&htim1);

														HAL_NVIC_DisableIRQ(EXTI9_5_IRQn);   	//Z
														HAL_NVIC_DisableIRQ(ADC_IRQn);			//ADC
														HAL_NVIC_DisableIRQ(TIM3_IRQn);			//ENCODER
														HAL_NVIC_DisableIRQ(TIM1_UP_IRQn);		//5 mS Timer

														Flag_BLE_Enable 		= 0;
														Flag_BLE_Read_ON 		= 0;
														Read_Input_Group_Mode 	= 0;
														Flag_BLE_Graph_ON		= 0;
														Flag_Job_Name_Received 	= 0;

														uint16_t temp_loop = 0,ref_count = 0;

														//Time around 2 sec so that any ongoing process gets completed
														for(ref_count = 0; ref_count < 10; ref_count++)
														{
															count = (hwwdg1.Instance->CR & 0x7F);
															for(temp_loop = 0; temp_loop <200; temp_loop++)
															{
																osDelay(1);
															}
															sprintf(str, "Count: %d\n", count);
															Send_String_UART_232((uint8_t*)str);
															HAL_IWDG_Refresh(&hiwdg1);
															HAL_WWDG_Refresh(&hwwdg1);
														}
														alt_second_ms = 0;
														Flag_Time_Second = 0;

														//Making All Digital Outputs Idle
														HAL_GPIO_WritePin(DO_1_GPIO_Port, DO_1_Pin,Pulse_Level_Idle);
														HAL_GPIO_WritePin(DO_2_GPIO_Port, DO_2_Pin,Pulse_Level_Idle);
														HAL_GPIO_WritePin(DO_3_GPIO_Port, DO_3_Pin,Pulse_Level_Idle);
														HAL_GPIO_WritePin(DO_4_GPIO_Port, DO_4_Pin,Pulse_Level_Idle);
														HAL_GPIO_WritePin(DO_5_GPIO_Port, DO_5_Pin,Pulse_Level_Idle);
														HAL_GPIO_WritePin(DO_6_GPIO_Port, DO_6_Pin,Pulse_Level_Idle);
														HAL_GPIO_WritePin(DO_7_GPIO_Port, DO_7_Pin,Pulse_Level_Idle);
														HAL_GPIO_WritePin(DO_8_GPIO_Port, DO_8_Pin,Pulse_Level_Idle);

														Flag_DMA_ON = 0;
														File_Name_Send_String();
//														Send_New_Data(Resp_Bytes,Resp_Length);
														BLE_Push_Data_DMA_Tx_Buffer(Resp_Bytes,Resp_Length);	//Added 30.09.25

														for(temp_loop = 0; temp_loop < 100; temp_loop++)
														{
															osDelay(1);
														}
														Transmit_Page_ID(Page_OTA);

														Flag_OTA_Request_Received = 1;


														temp_loop = 0;
														while(1)
														{
															  temp_loop++;
															  if(temp_loop >= 250)
															  {
																  temp_loop = 0;
																  count = (hwwdg1.Instance->CR & 0x7F);

																  HAL_GPIO_TogglePin(LED_RED_GPIO_Port,LED_RED_Pin);
//																  //Refresh @ everey 250 mS
																  sprintf(str, "WD: %d\n", count);
																  Send_String_UART_232((uint8_t*)str);
																  HAL_IWDG_Refresh(&hiwdg1);
																  HAL_WWDG_Refresh(&hwwdg1);
															  }
															  osDelay(1);
														}
													}
													break;

Here WD is printed couple of times and my system resets due to watchdog without its ISR being triggered. In he other tasks I initialize TFTP client as the file transfer is done using TFTP.

[jowakar122]

I had a doubt about RTOS blocking the WWDG ISR. So I have implemented without RTOS and the issue persists. 

int main(void)
{

  /* USER CODE BEGIN 1 */

  /* USER CODE END 1 */

  /* MPU Configuration--------------------------------------------------------*/
  MPU_Config();

  /* Enable the CPU Cache */

  /* Enable I-Cache---------------------------------------------------------*/
  SCB_EnableICache();

  /* Enable D-Cache---------------------------------------------------------*/
  SCB_EnableDCache();

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_USART3_UART_Init();
  MX_TIM24_Init();
  MX_LWIP_Init();
  MX_WWDG1_Init();
  /* USER CODE BEGIN 2 */
  HAL_UART_Transmit(&huart3, "OS Starts\n", 10, 10);
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
	  HAL_WWDG_Refresh(&hwwdg1);
	  HAL_GPIO_TogglePin(GPIOB, LED_GREEN_Pin);
	  MX_LWIP_Process();
	  if(!FLAG_OTA)
	  {
		  if((FLAG_LINK) && (!FLAG_TCP_CONNECTED))
		  {
			  tcp_client_init();
		  }
	  }
	  else
	  {
		  if(!FLAG_TFTP_CON)
		  {
			  HAL_UART_Transmit(&huart3, "TFTP\n", 5, 5);
			  tftp_init_client();
//			  HAL_Delay(10);
		  }

		  if(FLAG_TFTP_CON) { if(!OACK_RECV) { send_rrq_periodic(); } }

		  if(Flag_TFTP_Error) { HAL_UART_Transmit(&huart3, "ERROR\n", 6, 5); /*NVIC_SystemReset();*/ }

		  if(Flag_FILE_RECVED)
		  {
			  uint32_t t_buf[1] = {tsize};
			  if(FLASH_If_Erase(ADDR_FLASH_SECTOR_7_BANK1, 1) == FLASHIF_OK)
			  {
				  if((FLASH_If_Write(ADDR_FLASH_SECTOR_7_BANK1, t_buf, 1)) != FLASHIF_OK)
				  {
					  strcpy(debug_string, "\r------>ERROR: Writing file size in flash<------\n");
					  HAL_UART_Transmit(&huart3, (uint8_t*)debug_string, strlen(debug_string), 10);
				  }
			  }
			  Flag_FILE_RECVED = 0;
//			  NVIC_SystemReset();
		  }
		}
		HAL_Delay(100);
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */

  }
  /* USER CODE END 3 */
}

This is what was printed in my log:

[jowakar122 · Accepted solution]

For now I am using a timer to refresh the WWDG when file transfer is happening and it is working fine. But couldn't figure out the reason behind the above mentioned unusual condition.