STM32F429ZI discovery board: CAN Bus Bit dominant error

[MZemz.1]

Hello,

I'm using the STM32F429ZI Discovery board to create a CAN Network.

I configured both CAN1 and CAN2 and got them working correctly in loopback mode.

But when I try running one or both in normal mode, I get the error code 5 in the LEC register

which means Bit dominant error .

I've tried several baud rates and configurations but I don't seem to find the correct solution.

Would you please help me debug this error?

My APB1 clock is at 36Mhz

My timing parameters are calculated using http://www.bittiming.can-wiki.info/ and have the following values:

Prescaler = 4 

  SyncJumpWidth = CAN_SJW_4TQ;

  TimeSeg1 = CAN_BS1_15TQ;

  TimeSeg2 = CAN_BS2_2TQ;

CAN Init functions:

static void MX_CAN1_Init(void)
{
 
  /* USER CODE BEGIN CAN1_Init 0 */
  /* USER CODE END CAN1_Init 0 */
 
  /* USER CODE BEGIN CAN1_Init 1 */
 
  /* USER CODE END CAN1_Init 1 */
  hcan1.Instance = CAN1;
  hcan1.Init.Prescaler = 4;
  hcan1.Init.Mode = CAN_MODE_NORMAL;
  hcan1.Init.SyncJumpWidth = CAN_SJW_4TQ;
  hcan1.Init.TimeSeg1 = CAN_BS1_15TQ;
  hcan1.Init.TimeSeg2 = CAN_BS2_2TQ;
  hcan1.Init.TimeTriggeredMode = DISABLE;
  hcan1.Init.AutoBusOff = ENABLE;
  hcan1.Init.AutoWakeUp = DISABLE;
  hcan1.Init.AutoRetransmission = DISABLE;
  hcan1.Init.ReceiveFifoLocked = DISABLE;
  hcan1.Init.TransmitFifoPriority = ENABLE;
  if (HAL_CAN_Init(&hcan1) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN CAN1_Init 2 */
  CAN_FilterTypeDef sFilterConfig = {0};
  /*##-2- Configure the CAN Filter ###########################################*/
  sFilterConfig.FilterBank = 0;
  sFilterConfig.FilterMode = CAN_FILTERMODE_IDMASK;
  sFilterConfig.FilterScale = CAN_FILTERSCALE_32BIT;
  sFilterConfig.FilterIdHigh = 0x0000;
  sFilterConfig.FilterIdLow = 0x0000;
  sFilterConfig.FilterMaskIdHigh = 0x0000;
  sFilterConfig.FilterMaskIdLow = 0x0000;
  sFilterConfig.FilterFIFOAssignment = CAN_RX_FIFO0;
  sFilterConfig.FilterActivation = ENABLE;
  sFilterConfig.SlaveStartFilterBank = 14;
 
  if(HAL_CAN_ConfigFilter(&hcan1, &sFilterConfig) != HAL_OK)
  {
    /* Filter configuration Error */
    Error_Handler();
  }
 
  /*##-3- Start the CAN peripheral ###########################################*/
  if (HAL_CAN_Start(&hcan1) != HAL_OK)
  {
    /* Start Error */
    Error_Handler();
  }
 
  /*##-4- Activate CAN RX notification #######################################*/
  if (HAL_CAN_ActivateNotification(&hcan1, CAN_IT_RX_FIFO0_MSG_PENDING) != HAL_OK)
  {
    /* Notification Error */
    Error_Handler();
  }
  /*##-5- Activate CAN BUSOFF notification ###################################*/
  if (HAL_CAN_ActivateNotification(&hcan1, CAN_IT_BUSOFF) != HAL_OK)
  {
	  /* Notification Error */
	  Error_Handler();
  }
 
  /* USER CODE END CAN1_Init 2 */
 
}
 
/**
  * @brief CAN2 Initialization Function
  * @param None
  * @retval None
  */
static void MX_CAN2_Init(void)
{
 
  /* USER CODE BEGIN CAN2_Init 0 */
 
  /* USER CODE END CAN2_Init 0 */
 
  /* USER CODE BEGIN CAN2_Init 1 */
 
  /* USER CODE END CAN2_Init 1 */
  hcan2.Instance = CAN2;
  hcan2.Init.Prescaler = 4;
  hcan2.Init.Mode = CAN_MODE_NORMAL;
  hcan2.Init.SyncJumpWidth = CAN_SJW_4TQ;
  hcan2.Init.TimeSeg1 = CAN_BS1_15TQ;
  hcan2.Init.TimeSeg2 = CAN_BS2_2TQ;
  hcan2.Init.TimeTriggeredMode = DISABLE;
  hcan2.Init.AutoBusOff = ENABLE;
  hcan2.Init.AutoWakeUp = DISABLE;
  hcan2.Init.AutoRetransmission = DISABLE;
  hcan2.Init.ReceiveFifoLocked = DISABLE;
  hcan2.Init.TransmitFifoPriority = ENABLE;
  if (HAL_CAN_Init(&hcan2) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN CAN2_Init 2 */
  CAN_FilterTypeDef sFilterConfig = {0};
  /*##-2- Configure the CAN Filter ###########################################*/
  sFilterConfig.FilterBank = 14;
  sFilterConfig.FilterMode = CAN_FILTERMODE_IDMASK;
  sFilterConfig.FilterScale = CAN_FILTERSCALE_32BIT;
  sFilterConfig.FilterIdHigh = 0x0000;
  sFilterConfig.FilterIdLow = 0x0000;
  sFilterConfig.FilterMaskIdHigh = 0x0000;
  sFilterConfig.FilterMaskIdLow = 0x0000;
  sFilterConfig.FilterFIFOAssignment = CAN_RX_FIFO0;
  sFilterConfig.FilterActivation = ENABLE;
  sFilterConfig.SlaveStartFilterBank = 14;
 
 
  if(HAL_CAN_ConfigFilter(&hcan2, &sFilterConfig) != HAL_OK)
  {
    /* Filter configuration Error */
    Error_Handler();
  }
 
  /*##-3- Start the CAN peripheral ###########################################*/
  if (HAL_CAN_Start(&hcan2) != HAL_OK)
  {
    /* Start Error */
    Error_Handler();
  }
  /*##-4- Activate CAN RX notification #######################################*/
  if (HAL_CAN_ActivateNotification(&hcan2, CAN_IT_RX_FIFO0_MSG_PENDING) != HAL_OK)
  {
    /* Notification Error */
    Error_Handler();
  }
  /*##-5- Activate CAN BUSOFF notification ###################################*/
  if (HAL_CAN_ActivateNotification(&hcan2, CAN_IT_BUSOFF) != HAL_OK)
  {
	  /* Notification Error */
	  Error_Handler();
  }
 
  /* USER CODE END CAN2_Init 2 */
 
}