DRESULT SD_read(BYTE lun, BYTE *buff, DWORD sector, UINT count)
{
  DRESULT res = RES_ERROR;
  uint32_t timeout;
  uint8_t ret;
#if (ENABLE_SD_DMA_CACHE_MAINTENANCE == 1)
  uint32_t alignedAddr;
#endif

  /*
  * ensure the SDCard is ready for a new operation
  */

  if (SD_CheckStatusWithTimeout(SD_TIMEOUT) < 0)
  {
    return res;
  }

#if defined(ENABLE_SCRATCH_BUFFER)
  if (!((uint32_t)buff & 0x3))
  {
#endif
    if(BSP_SD_ReadBlocks_DMA((uint32_t*)buff,
                             (uint32_t) (sector),
                             count) == MSD_OK)
    {
      ReadStatus = 0;
      /* Wait that the reading process is completed or a timeout occurs */
      timeout = HAL_GetTick();
      while((ReadStatus == 0) && ((HAL_GetTick() - timeout) < SD_TIMEOUT))
      {
      }
      /* incase of a timeout return error */
      if (ReadStatus == 0)
      {
        res = RES_ERROR;
      }
      else
      {
        ReadStatus = 0;
        timeout = HAL_GetTick();

        while((HAL_GetTick() - timeout) < SD_TIMEOUT)
        {
          if (BSP_SD_GetCardState() == SD_TRANSFER_OK)
          {
            res = RES_OK;
#if (ENABLE_SD_DMA_CACHE_MAINTENANCE == 1)
            /*
            the SCB_InvalidateDCache_by_Addr() requires a 32-Byte aligned address,
            adjust the address and the D-Cache size to invalidate accordingly.
            */
            alignedAddr = (uint32_t)buff & ~0x1F;
            SCB_InvalidateDCache_by_Addr((uint32_t*)alignedAddr, count*BLOCKSIZE + ((uint32_t)buff - alignedAddr));
#endif
            break;
          }
        }
      }
    }
#if defined(ENABLE_SCRATCH_BUFFER)
    else {
      /* Slow path, fetch each sector a part and memcpy to destination buffer */
      int i;

      for (i = 0; i < count; i++) {
        ret = BSP_SD_ReadBlocks_DMA((uint32_t*)scratch, (uint32_t)sector++, 1);
        if (ret == MSD_OK) {
          /* wait until the read is successful or a timeout occurs */

          ReadStatus = 0;
          timeout = HAL_GetTick();
          while((ReadStatus == 0) && ((HAL_GetTick() - timeout) < SD_TIMEOUT))
          {
          }
          if (ReadStatus == 0)
          {
            break;
          }


#if (ENABLE_SD_DMA_CACHE_MAINTENANCE == 1)
          /*
          *
          * invalidate the scratch buffer before the next read to get the actual data instead of the cached one
          */
          SCB_InvalidateDCache_by_Addr((uint32_t*)scratch, BLOCKSIZE);
#endif
          memcpy(buff, scratch, BLOCKSIZE);
          buff += BLOCKSIZE;
        }
        else
        {
          break;
        }
      }

      if ((i == count) && (ret == MSD_OK))
        res = RES_OK;
    }
#endif
  }

  return res;
}
/**
* @brief  Writes Sector(s)
* @param  lun : not used
* @param  *buff: Data to be written
* @param  sector: Sector address (LBA)
* @param  count: Number of sectors to write (1..128)
* @retval DRESULT: Operation result
*/
#if _USE_WRITE == 1
DRESULT SD_write(BYTE lun, const BYTE *buff, DWORD sector, UINT count)
{
  DRESULT res = RES_ERROR;
  uint32_t timeout;
  uint8_t ret;
  int i;

   WriteStatus = 0;
#if (ENABLE_SD_DMA_CACHE_MAINTENANCE == 1)
  uint32_t alignedAddr;
#endif

  if (SD_CheckStatusWithTimeout(SD_TIMEOUT) < 0)
  {
    return res;
  }

#if defined(ENABLE_SCRATCH_BUFFER)
  if (!((uint32_t)buff & 0x3))
  {
#endif
#if (ENABLE_SD_DMA_CACHE_MAINTENANCE == 1)

    /*
    the SCB_CleanDCache_by_Addr() requires a 32-Byte aligned address
    adjust the address and the D-Cache size to clean accordingly.
    */
    alignedAddr = (uint32_t)buff &  ~0x1F;
    SCB_CleanDCache_by_Addr((uint32_t*)alignedAddr, count*BLOCKSIZE + ((uint32_t)buff - alignedAddr));
#endif


    if(BSP_SD_WriteBlocks_DMA((uint32_t*)buff,
                              (uint32_t)(sector),
                              count) == MSD_OK)
    {
      /* Wait that writing process is completed or a timeout occurs */

      timeout = HAL_GetTick();
      while((WriteStatus == 0) && ((HAL_GetTick() - timeout) < SD_TIMEOUT))
      {
      }
      /* incase of a timeout return error */
      if (WriteStatus == 0)
      {
        res = RES_ERROR;
      }
      else
      {
        WriteStatus = 0;
        timeout = HAL_GetTick();

        while((HAL_GetTick() - timeout) < SD_TIMEOUT)
        {
          if (BSP_SD_GetCardState() == SD_TRANSFER_OK)
          {
            res = RES_OK;
            break;
          }
        }
      }
    }
    else
    {
      /* Slow path, fetch each sector a part and memcpy to destination buffer */
#if (ENABLE_SD_DMA_CACHE_MAINTENANCE == 1)
      /*
      * invalidate the scratch buffer before the next write to get the actual data instead of the cached one
      */
      SCB_InvalidateDCache_by_Addr((uint32_t*)scratch, BLOCKSIZE);
#endif

      for (i = 0; i < count; i++)
      {
        WriteStatus = 0;
        ret = BSP_SD_WriteBlocks_DMA((uint32_t*)scratch, (uint32_t)sector++, 1);
        if (ret == MSD_OK) {
          /* wait for a message from the queue or a timeout */
          timeout = HAL_GetTick();
          while((WriteStatus == 0) && ((HAL_GetTick() - timeout) < SD_TIMEOUT))
          {
          }
          if (WriteStatus == 0)
          {
            break;
          }

          memcpy((void *)buff, (void *)scratch, BLOCKSIZE);
          buff += BLOCKSIZE;
        }
        else
        {
          break;
        }
      }
      if ((i == count) && (ret == MSD_OK))
        res = RES_OK;
    }

  }
  return res;
}