Rxmessage process in case of CAN1 and CAN2 for STM32F407

[Ash1]

Hi 

I want to understand Rx message process in case of can2. Rx fifo code I have tested when I used only CAN1 it is working fine. I have put RxFifoMSgpendingcallback function in IRQhandler and further code is working fine for when I used only one (CAN1) controller ,can you help me to understand what change I should do when I am using CAN1 and CAN2 both controller so that I can receive for both controller data.

/* Receive FIFO 0 message pending interrupt management *********************/
  if ((interrupts & CAN_IT_RX_FIFO0_MSG_PENDING) != 0U)
  {
    /* Check if message is still pending */
    if ((hcan->Instance->RF0R & CAN_RF0R_FMP0) != 0U)
    {
      /* Receive FIFO 0 message pending Callback */
#if USE_HAL_CAN_REGISTER_CALLBACKS == 1
      /* Call registered callback*/
      hcan->RxFifo0MsgPendingCallback(hcan);
#else
      /* Call weak (surcharged) callback */
      HAL_CAN_RxFifo0MsgPendingCallback(hcan);
#endif /* USE_HAL_CAN_REGISTER_CALLBACKS */
    }
  }



void CANRxFifo0MsgPendingCallback(CAN_HandleTypeDef *hcan)
{
	CAN_RxHeaderTypeDef rx_header;
	uint8_t rx_data[8];

	if (HAL_CAN_GetRxMessage(&hcan1, CAN_RX_FIFO0, &rx_header, rx_data) != HAL_OK)
	{
		Error_Handler();
	}


}



HAL_StatusTypeDef HAL_CAN_GetRxMessage(CAN_HandleTypeDef *hcan, uint32_t RxFifo,
                                       CAN_RxHeaderTypeDef *pHeader, uint8_t aData[])
{
  HAL_CAN_StateTypeDef state = hcan->State;

  assert_param(IS_CAN_RX_FIFO(RxFifo));

  if ((state == HAL_CAN_STATE_READY) ||
      (state == HAL_CAN_STATE_LISTENING))
  {
    /* Check the Rx FIFO */
    if (RxFifo == CAN_RX_FIFO0) /* Rx element is assigned to Rx FIFO 0 */
    {
      /* Check that the Rx FIFO 0 is not empty */
      if ((hcan->Instance->RF0R & CAN_RF0R_FMP0) == 0U)
      {
        /* Update error code */
        hcan->ErrorCode |= HAL_CAN_ERROR_PARAM;

        return HAL_ERROR;
      }
    }
    else /* Rx element is assigned to Rx FIFO 1 */
    {
      /* Check that the Rx FIFO 1 is not empty */
      if ((hcan->Instance->RF1R & CAN_RF1R_FMP1) == 0U)
      {
        /* Update error code */
        hcan->ErrorCode |= HAL_CAN_ERROR_PARAM;

        return HAL_ERROR;
      }
    }

    /* Get the header */
    pHeader->IDE = CAN_RI0R_IDE & hcan->Instance->sFIFOMailBox[RxFifo].RIR;
    if (pHeader->IDE == CAN_ID_STD)
    {
      pHeader->StdId = (CAN_RI0R_STID & hcan->Instance->sFIFOMailBox[RxFifo].RIR) >> CAN_TI0R_STID_Pos;
    }
    else
    {
      pHeader->ExtId = ((CAN_RI0R_EXID | CAN_RI0R_STID) &
                        hcan->Instance->sFIFOMailBox[RxFifo].RIR) >> CAN_RI0R_EXID_Pos;
    }
    pHeader->RTR = (CAN_RI0R_RTR & hcan->Instance->sFIFOMailBox[RxFifo].RIR);
    if (((CAN_RDT0R_DLC & hcan->Instance->sFIFOMailBox[RxFifo].RDTR) >> CAN_RDT0R_DLC_Pos) >= 8U)
    {
      /* Truncate DLC to 8 if received field is over range */
      pHeader->DLC = 8U;
    }
    else
    {
      pHeader->DLC = (CAN_RDT0R_DLC & hcan->Instance->sFIFOMailBox[RxFifo].RDTR) >> CAN_RDT0R_DLC_Pos;
    }

    pHeader->FilterMatchIndex = (CAN_RDT0R_FMI & hcan->Instance->sFIFOMailBox[RxFifo].RDTR) >> CAN_RDT0R_FMI_Pos;
    pHeader->Timestamp = (CAN_RDT0R_TIME & hcan->Instance->sFIFOMailBox[RxFifo].RDTR) >> CAN_RDT0R_TIME_Pos;

    /* Get the data */
    aData[0] = (uint8_t)((CAN_RDL0R_DATA0 & hcan->Instance->sFIFOMailBox[RxFifo].RDLR) >> CAN_RDL0R_DATA0_Pos);
    aData[1] = (uint8_t)((CAN_RDL0R_DATA1 & hcan->Instance->sFIFOMailBox[RxFifo].RDLR) >> CAN_RDL0R_DATA1_Pos);
    aData[2] = (uint8_t)((CAN_RDL0R_DATA2 & hcan->Instance->sFIFOMailBox[RxFifo].RDLR) >> CAN_RDL0R_DATA2_Pos);
    aData[3] = (uint8_t)((CAN_RDL0R_DATA3 & hcan->Instance->sFIFOMailBox[RxFifo].RDLR) >> CAN_RDL0R_DATA3_Pos);
    aData[4] = (uint8_t)((CAN_RDH0R_DATA4 & hcan->Instance->sFIFOMailBox[RxFifo].RDHR) >> CAN_RDH0R_DATA4_Pos);
    aData[5] = (uint8_t)((CAN_RDH0R_DATA5 & hcan->Instance->sFIFOMailBox[RxFifo].RDHR) >> CAN_RDH0R_DATA5_Pos);
    aData[6] = (uint8_t)((CAN_RDH0R_DATA6 & hcan->Instance->sFIFOMailBox[RxFifo].RDHR) >> CAN_RDH0R_DATA6_Pos);
    aData[7] = (uint8_t)((CAN_RDH0R_DATA7 & hcan->Instance->sFIFOMailBox[RxFifo].RDHR) >> CAN_RDH0R_DATA7_Pos);

    /* Release the FIFO */
    if (RxFifo == CAN_RX_FIFO0) /* Rx element is assigned to Rx FIFO 0 */
    {
      /* Release RX FIFO 0 */
      SET_BIT(hcan->Instance->RF0R, CAN_RF0R_RFOM0);
    }
    else /* Rx element is assigned to Rx FIFO 1 */
    {
      /* Release RX FIFO 1 */
      SET_BIT(hcan->Instance->RF1R, CAN_RF1R_RFOM1);
    }

    /* Return function status */
    return HAL_OK;
  }
  else
  {
    /* Update error code */
    hcan->ErrorCode |= HAL_CAN_ERROR_NOT_INITIALIZED;

    return HAL_ERROR;
  }
}

[SofLit · Accepted solution]

Hello,

In the Rx callback you need to test on the CAN instance that received the message and read it using HAL_CAN_GetRxMessage():

void HAL_CAN_RxFifo0MsgPendingCallback(CAN_HandleTypeDef *hcan)
{
  /* Get RX message */
  if(hcan->Instance == CAN1)
  {
    if (HAL_CAN_GetRxMessage(hcan, CAN_RX_FIFO0, &CAN1_RxHeader, CAN1_RxData) != HAL_OK)
      {
         /* Reception Error */
         Error_Handler();
      }
  }
  else if(hcan->Instance == CAN2) 
  {
     if (HAL_CAN_GetRxMessage(hcan, CAN_RX_FIFO0, &CAN2_RxHeader, CAN2_RxData) != HAL_OK)
      {
         /* Reception Error */
         Error_Handler();
      }
  }    

}

 Hope that answered your question.