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STM32F103C8t - CAN problem

Question asked by keshavarz.abbas on Mar 15, 2018
Latest reply on Mar 16, 2018 by T J

Hello guys!

I am new in using CAN interface, and for the first time, I started to use it in my project. I used STM32F103C8t. When I wanted to use CAN interface, there only happens time-out exception in run-time and I figured it out both in run-mode and then in debug mode. I wrote a very small project to work on it and I got the same problem. I doubted if the mcu is not working well, I changed it and still not change, I even changed the mcu with stm32f103cBt one and no change either.

I give you the simple code I created using HAL library and STM32Cube here and I hope you can help me

this is the code:

 

In this code if CAN works, the relay must toggle almost in 10HZ frequency, and if time-out happens the relay must toggle in 1Hz frequency. In practice, the relay toggles in 1Hz!!!

 

CAN_HandleTypeDef hcan;

CanTxMsgTypeDef    can_tx_msg;
CanRxMsgTypeDef    can_rx_msg;


uint8_t can_tx_buff[8];


int main(void)
{
  /* USER CODE BEGIN 1 */
    char *msg = "salam";

  /* USER CODE END 1 */

  /* 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_CAN_Init();
  /* USER CODE BEGIN 2 */
    hcan.pTxMsg = &can_tx_msg;
    hcan.pRxMsg = &can_rx_msg;

  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
        sprintf( (char *) hcan.pTxMsg->Data, "%s", msg );
        hcan.pTxMsg->DLC = strlen(msg);
        HAL_CAN_Transmit(&hcan,1000);    
        HAL_Delay(100);
        HAL_GPIO_TogglePin( relay_test_GPIO_Port, relay_test_Pin );
  /* USER CODE END WHILE */

  /* USER CODE BEGIN 3 */

  }
  /* USER CODE END 3 */

}

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{

  RCC_OscInitTypeDef RCC_OscInitStruct;
  RCC_ClkInitTypeDef RCC_ClkInitStruct;

    /**Initializes the CPU, AHB and APB busses clocks
    */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.HSICalibrationValue = 16;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI_DIV2;
  RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL16;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    _Error_Handler(__FILE__, __LINE__);
  }

    /**Initializes the CPU, AHB and APB busses clocks
    */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
  {
    _Error_Handler(__FILE__, __LINE__);
  }

    /**Configure the Systick interrupt time
    */
  HAL_SYSTICK_Config(HAL_RCC_GetHCLKFreq()/1000);

    /**Configure the Systick
    */
  HAL_SYSTICK_CLKSourceConfig(SYSTICK_CLKSOURCE_HCLK);

  /* SysTick_IRQn interrupt configuration */
  HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
}

/* CAN init function */
static void MX_CAN_Init(void)
{

  hcan.Instance = CAN1;
  hcan.Init.Prescaler = 16;
  hcan.Init.Mode = CAN_MODE_NORMAL;
  hcan.Init.SJW = CAN_SJW_1TQ;
  hcan.Init.BS1 = CAN_BS1_1TQ;
  hcan.Init.BS2 = CAN_BS2_1TQ;
  hcan.Init.TTCM = DISABLE;
  hcan.Init.ABOM = DISABLE;
  hcan.Init.AWUM = DISABLE;
  hcan.Init.NART = DISABLE;
  hcan.Init.RFLM = DISABLE;
  hcan.Init.TXFP = DISABLE;
  if (HAL_CAN_Init(&hcan) != HAL_OK)
  {
    _Error_Handler(__FILE__, __LINE__);
  }
}

/** Configure pins as
        * Analog
        * Input
        * Output
        * EVENT_OUT
        * EXTI
*/
static void MX_GPIO_Init(void)
{

  GPIO_InitTypeDef GPIO_InitStruct;

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOA_CLK_ENABLE();

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(relay_test_GPIO_Port, relay_test_Pin, GPIO_PIN_RESET);

  /*Configure GPIO pin : relay_test_Pin */
  GPIO_InitStruct.Pin = relay_test_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(relay_test_GPIO_Port, &GPIO_InitStruct);
}

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