[STM32 read CAN FD buffer] #STM32 #embedded #CAN

stm32_read_can_buffer.c

  uint32_t GetIndex = 0;

          /* Calculate Rx FIFO 0 element index */
        GetIndex += ((hfdcan->Instance->RXF0S & FDCAN_RXF0S_F0GI) >> FDCAN_RXF0S_F0GI_Pos);

        /* Calculate Rx FIFO 0 element address */
        RxAddress = (uint32_t *)(hfdcan->msgRam.RxFIFO0SA + (GetIndex * SRAMCAN_RF0_SIZE));

            /* Retrieve IdType */
    pRxHeader->IdType = *RxAddress & FDCAN_ELEMENT_MASK_XTD;

    /* Retrieve Identifier */
    if (pRxHeader->IdType == FDCAN_STANDARD_ID) /* Standard ID element */
    {
      pRxHeader->Identifier = ((*RxAddress & FDCAN_ELEMENT_MASK_STDID) >> 18U);
    }
    else /* Extended ID element */
    {
      pRxHeader->Identifier = (*RxAddress & FDCAN_ELEMENT_MASK_EXTID);
    }

    /* Retrieve RxFrameType */
    pRxHeader->RxFrameType = (*RxAddress & FDCAN_ELEMENT_MASK_RTR);

    /* Retrieve ErrorStateIndicator */
    pRxHeader->ErrorStateIndicator = (*RxAddress & FDCAN_ELEMENT_MASK_ESI);

    /* Increment RxAddress pointer to second word of Rx FIFO element */
    RxAddress++;

    /* Retrieve RxTimestamp */
    pRxHeader->RxTimestamp = (*RxAddress & FDCAN_ELEMENT_MASK_TS);

    /* Retrieve DataLength */
    pRxHeader->DataLength = ((*RxAddress & FDCAN_ELEMENT_MASK_DLC) >> 16U);

    /* Retrieve BitRateSwitch */
    pRxHeader->BitRateSwitch = (*RxAddress & FDCAN_ELEMENT_MASK_BRS);

    /* Retrieve FDFormat */
    pRxHeader->FDFormat = (*RxAddress & FDCAN_ELEMENT_MASK_FDF);

    /* Retrieve FilterIndex */
    pRxHeader->FilterIndex = ((*RxAddress & FDCAN_ELEMENT_MASK_FIDX) >> 24U);

    /* Retrieve NonMatchingFrame */
    pRxHeader->IsFilterMatchingFrame = ((*RxAddress & FDCAN_ELEMENT_MASK_ANMF) >> 31U);

    /* Increment RxAddress pointer to payload of Rx FIFO element */
    RxAddress++;

    /* Retrieve Rx payload */
    pData = (uint8_t *)RxAddress;
    for (ByteCounter = 0; ByteCounter < DLCtoBytes[pRxHeader->DataLength]; ByteCounter++)
    {
      pRxData[ByteCounter] = pData[ByteCounter];
    }

    if (RxLocation == FDCAN_RX_FIFO0) /* Rx element is assigned to the Rx FIFO 0 */
    {
      /* Acknowledge the Rx FIFO 0 that the oldest element is read so that it increments the GetIndex */
      hfdcan->Instance->RXF0A = GetIndex;
    }
    else /* Rx element is assigned to the Rx FIFO 1 */
    {
      /* Acknowledge the Rx FIFO 1 that the oldest element is read so that it increments the GetIndex */
      hfdcan->Instance->RXF1A = GetIndex;
    }