stm32_eval_spi_sd.c

STM32的SPI1与SPI2通信

      }
    }
    /*!< Get CRC bytes (not really needed by us, but required by SD) */
    SD_WriteByte(SD_DUMMY_BYTE);
    SD_WriteByte(SD_DUMMY_BYTE);
    /*!< Set response value to success */
    rvalue = SD_RESPONSE_NO_ERROR;
  }
  /*!< SD chip select high */
  SD_CS_HIGH();
  /*!< Send dummy byte: 8 Clock pulses of delay */
  SD_WriteByte(SD_DUMMY_BYTE);

  /*!< Byte 0 */
  SD_csd->CSDStruct = (CSD_Tab[0] & 0xC0) >> 6;
  SD_csd->SysSpecVersion = (CSD_Tab[0] & 0x3C) >> 2;
  SD_csd->Reserved1 = CSD_Tab[0] & 0x03;

  /*!< Byte 1 */
  SD_csd->TAAC = CSD_Tab[1];

  /*!< Byte 2 */
  SD_csd->NSAC = CSD_Tab[2];

  /*!< Byte 3 */
  SD_csd->MaxBusClkFrec = CSD_Tab[3];

  /*!< Byte 4 */
  SD_csd->CardComdClasses = CSD_Tab[4] << 4;

  /*!< Byte 5 */
  SD_csd->CardComdClasses |= (CSD_Tab[5] & 0xF0) >> 4;
  SD_csd->RdBlockLen = CSD_Tab[5] & 0x0F;

  /*!< Byte 6 */
  SD_csd->PartBlockRead = (CSD_Tab[6] & 0x80) >> 7;
  SD_csd->WrBlockMisalign = (CSD_Tab[6] & 0x40) >> 6;
  SD_csd->RdBlockMisalign = (CSD_Tab[6] & 0x20) >> 5;
  SD_csd->DSRImpl = (CSD_Tab[6] & 0x10) >> 4;
  SD_csd->Reserved2 = 0; /*!< Reserved */

  SD_csd->DeviceSize = (CSD_Tab[6] & 0x03) << 10;

  /*!< Byte 7 */
  SD_csd->DeviceSize |= (CSD_Tab[7]) << 2;

  /*!< Byte 8 */
  SD_csd->DeviceSize |= (CSD_Tab[8] & 0xC0) >> 6;

  SD_csd->MaxRdCurrentVDDMin = (CSD_Tab[8] & 0x38) >> 3;
  SD_csd->MaxRdCurrentVDDMax = (CSD_Tab[8] & 0x07);

  /*!< Byte 9 */
  SD_csd->MaxWrCurrentVDDMin = (CSD_Tab[9] & 0xE0) >> 5;
  SD_csd->MaxWrCurrentVDDMax = (CSD_Tab[9] & 0x1C) >> 2;
  SD_csd->DeviceSizeMul = (CSD_Tab[9] & 0x03) << 1;
  /*!< Byte 10 */
  SD_csd->DeviceSizeMul |= (CSD_Tab[10] & 0x80) >> 7;
    
  SD_csd->EraseGrSize = (CSD_Tab[10] & 0x40) >> 6;
  SD_csd->EraseGrMul = (CSD_Tab[10] & 0x3F) << 1;

  /*!< Byte 11 */
  SD_csd->EraseGrMul |= (CSD_Tab[11] & 0x80) >> 7;
  SD_csd->WrProtectGrSize = (CSD_Tab[11] & 0x7F);

  /*!< Byte 12 */
  SD_csd->WrProtectGrEnable = (CSD_Tab[12] & 0x80) >> 7;
  SD_csd->ManDeflECC = (CSD_Tab[12] & 0x60) >> 5;
  SD_csd->WrSpeedFact = (CSD_Tab[12] & 0x1C) >> 2;
  SD_csd->MaxWrBlockLen = (CSD_Tab[12] & 0x03) << 2;

  /*!< Byte 13 */
  SD_csd->MaxWrBlockLen |= (CSD_Tab[13] & 0xC0) >> 6;
  SD_csd->WriteBlockPaPartial = (CSD_Tab[13] & 0x20) >> 5;
  SD_csd->Reserved3 = 0;
  SD_csd->ContentProtectAppli = (CSD_Tab[13] & 0x01);

  /*!< Byte 14 */
  SD_csd->FileFormatGrouop = (CSD_Tab[14] & 0x80) >> 7;
  SD_csd->CopyFlag = (CSD_Tab[14] & 0x40) >> 6;
  SD_csd->PermWrProtect = (CSD_Tab[14] & 0x20) >> 5;
  SD_csd->TempWrProtect = (CSD_Tab[14] & 0x10) >> 4;
  SD_csd->FileFormat = (CSD_Tab[14] & 0x0C) >> 2;
  SD_csd->ECC = (CSD_Tab[14] & 0x03);

  /*!< Byte 15 */
  SD_csd->CSD_CRC = (CSD_Tab[15] & 0xFE) >> 1;
  SD_csd->Reserved4 = 1;

  /*!< Return the reponse */
  return rvalue;
}

/**
  * @brief  Read the CID card register.
  *         Reading the contents of the CID register in SPI mode is a simple 
  *         read-block transaction.
  * @param  SD_cid: pointer on an CID register structure
  * @retval The SD Response: 
  *         - SD_RESPONSE_FAILURE: Sequence failed
  *         - SD_RESPONSE_NO_ERROR: Sequence succeed
  */
SD_Error SD_GetCIDRegister(SD_CID* SD_cid)
{
  uint32_t i = 0;
  SD_Error rvalue = SD_RESPONSE_FAILURE;
  uint8_t CID_Tab[16];
  
  /*!< SD chip select low */
  SD_CS_LOW();
  
  /*!< Send CMD10 (CID register) */
  SD_SendCmd(SD_CMD_SEND_CID, 0, 0xFF);
  
  /*!< Wait for response in the R1 format (0x00 is no errors) */
  if (!SD_GetResponse(SD_RESPONSE_NO_ERROR))
  {
    if (!SD_GetResponse(SD_START_DATA_SINGLE_BLOCK_READ))
    {
      /*!< Store CID register value on CID_Tab */
      for (i = 0; i < 16; i++)
      {
        CID_Tab[i] = SD_ReadByte();
      }
    }
    /*!< Get CRC bytes (not really needed by us, but required by SD) */
    SD_WriteByte(SD_DUMMY_BYTE);
    SD_WriteByte(SD_DUMMY_BYTE);
    /*!< Set response value to success */
    rvalue = SD_RESPONSE_NO_ERROR;
  }
  /*!< SD chip select high */
  SD_CS_HIGH();
  /*!< Send dummy byte: 8 Clock pulses of delay */
  SD_WriteByte(SD_DUMMY_BYTE);

  /*!< Byte 0 */
  SD_cid->ManufacturerID = CID_Tab[0];

  /*!< Byte 1 */
  SD_cid->OEM_AppliID = CID_Tab[1] << 8;

  /*!< Byte 2 */
  SD_cid->OEM_AppliID |= CID_Tab[2];

  /*!< Byte 3 */
  SD_cid->ProdName1 = CID_Tab[3] << 24;

  /*!< Byte 4 */
  SD_cid->ProdName1 |= CID_Tab[4] << 16;

  /*!< Byte 5 */
  SD_cid->ProdName1 |= CID_Tab[5] << 8;

  /*!< Byte 6 */
  SD_cid->ProdName1 |= CID_Tab[6];

  /*!< Byte 7 */
  SD_cid->ProdName2 = CID_Tab[7];

  /*!< Byte 8 */
  SD_cid->ProdRev = CID_Tab[8];

  /*!< Byte 9 */
  SD_cid->ProdSN = CID_Tab[9] << 24;

  /*!< Byte 10 */
  SD_cid->ProdSN |= CID_Tab[10] << 16;

  /*!< Byte 11 */
  SD_cid->ProdSN |= CID_Tab[11] << 8;

  /*!< Byte 12 */
  SD_cid->ProdSN |= CID_Tab[12];

  /*!< Byte 13 */
  SD_cid->Reserved1 |= (CID_Tab[13] & 0xF0) >> 4;
  SD_cid->ManufactDate = (CID_Tab[13] & 0x0F) << 8;

  /*!< Byte 14 */
  SD_cid->ManufactDate |= CID_Tab[14];

  /*!< Byte 15 */
  SD_cid->CID_CRC = (CID_Tab[15] & 0xFE) >> 1;
  SD_cid->Reserved2 = 1;

  /*!< Return the reponse */
  return rvalue;
}

/**
  * @brief  Send 5 bytes command to the SD card.
  * @param  Cmd: The user expected command to send to SD card.
  * @param  Arg: The command argument.
  * @param  Crc: The CRC.
  * @retval None
  */
void SD_SendCmd(uint8_t Cmd, uint32_t Arg, uint8_t Crc)
{
  uint32_t i = 0x00;
  
  uint8_t Frame[6];
  
  Frame[0] = (Cmd | 0x40); /*!< Construct byte 1 */
  
  Frame[1] = (uint8_t)(Arg >> 24); /*!< Construct byte 2 */
  
  Frame[2] = (uint8_t)(Arg >> 16); /*!< Construct byte 3 */
  
  Frame[3] = (uint8_t)(Arg >> 8); /*!< Construct byte 4 */
  
  Frame[4] = (uint8_t)(Arg); /*!< Construct byte 5 */
  
  Frame[5] = (Crc); /*!< Construct CRC: byte 6 */
  
  for (i = 0; i < 6; i++)
  {
    SD_WriteByte(Frame[i]); /*!< Send the Cmd bytes */
  }
}

/**
  * @brief  Get SD card data response.
  * @param  None
  * @retval The SD status: Read data response xxx0<status>1
  *         - status 010: Data accecpted
  *         - status 101: Data rejected due to a crc error
  *         - status 110: Data rejected due to a Write error.
  *         - status 111: Data rejected due to other error.
  */
uint8_t SD_GetDataResponse(void)
{
  uint32_t i = 0;
  uint8_t response, rvalue;

  while (i <= 64)
  {
    /*!< Read resonse */
    response = SD_ReadByte();
    /*!< Mask unused bits */
    response &= 0x1F;
    switch (response)
    {
      case SD_DATA_OK:
      {
        rvalue = SD_DATA_OK;
        break;
      }
      case SD_DATA_CRC_ERROR:
        return SD_DATA_CRC_ERROR;
      case SD_DATA_WRITE_ERROR:
        return SD_DATA_WRITE_ERROR;
      default:
      {
        rvalue = SD_DATA_OTHER_ERROR;
        break;
      }
    }
    /*!< Exit loop in case of data ok */
    if (rvalue == SD_DATA_OK)
      break;
    /*!< Increment loop counter */
    i++;
  }

  /*!< Wait null data */
  while (SD_ReadByte() == 0);

  /*!< Return response */
  return response;
}

/**
  * @brief  Returns the SD response.
  * @param  None
  * @retval The SD Response: 
  *         - SD_RESPONSE_FAILURE: Sequence failed
  *         - SD_RESPONSE_NO_ERROR: Sequence succeed
  */
SD_Error SD_GetResponse(uint8_t Response)
{
  uint32_t Count = 0xFFF;

  /*!< Check if response is got or a timeout is happen */
  while ((SD_ReadByte() != Response) && Count)
  {
    Count--;
  }
  if (Count == 0)
  {
    /*!< After time out */
    return SD_RESPONSE_FAILURE;
  }
  else
  {
    /*!< Right response got */
    return SD_RESPONSE_NO_ERROR;
  }
}

/**
  * @brief  Returns the SD status.
  * @param  None
  * @retval The SD status.
  */
uint16_t SD_GetStatus(void)
{
  uint16_t Status = 0;

  /*!< SD chip select low */
  SD_CS_LOW();

  /*!< Send CMD13 (SD_SEND_STATUS) to get SD status */
  SD_SendCmd(SD_CMD_SEND_STATUS, 0, 0xFF);

  Status = SD_ReadByte();
  Status |= (uint16_t)(SD_ReadByte() << 8);

  /*!< SD chip select high */
  SD_CS_HIGH();

  /*!< Send dummy byte 0xFF */
  SD_WriteByte(SD_DUMMY_BYTE);

  return Status;
}

/**
  * @brief  Put SD in Idle state.
  * @param  None
  * @retval The SD Response: 
  *         - SD_RESPONSE_FAILURE: Sequence failed
  *         - SD_RESPONSE_NO_ERROR: Sequence succeed
  */
SD_Error SD_GoIdleState(void)
{
  /*!< SD chip select low */
  SD_CS_LOW();
  
  /*!< Send CMD0 (SD_CMD_GO_IDLE_STATE) to put SD in SPI mode */
  SD_SendCmd(SD_CMD_GO_IDLE_STATE, 0, 0x95);
  
  /*!< Wait for In Idle State Response (R1 Format) equal to 0x01 */
  if (SD_GetResponse(SD_IN_IDLE_STATE))
  {
    /*!< No Idle State Response: return response failue */
    return SD_RESPONSE_FAILURE;
  }
  /*----------Activates the card initialization process-----------*/
  do
  {
    /*!< SD chip select high */
    SD_CS_HIGH();
    
    /*!< Send Dummy byte 0xFF */
    SD_WriteByte(SD_DUMMY_BYTE);
    
    /*!< SD chip select low */
    SD_CS_LOW();
    
    /*!< Send CMD1 (Activates the card process) until response equal to 0x0 */
    SD_SendCmd(SD_CMD_SEND_OP_COND, 0, 0xFF);
    /*!< Wait for no error Response (R1 Format) equal to 0x00 */
  }
  while (SD_GetResponse(SD_RESPONSE_NO_ERROR));
  
  /*!< SD chip select high */
  SD_CS_HIGH();
  
  /*!< Send dummy byte 0xFF */
  SD_WriteByte(SD_DUMMY_BYTE);
  
  return SD_RESPONSE_NO_ERROR;
}

/**
  * @brief  Write a byte on the SD.
  * @param  Data: byte to send.
  * @retval None
  */
uint8_t SD_WriteByte(uint8_t Data)
{
  /*!< Wait until the transmit buffer is empty */
  while(SPI_I2S_GetFlagStatus(SD_SPI, SPI_I2S_FLAG_TXE) == RESET)
  {
  }
  
  /*!< Send the byte */
  SPI_I2S_SendData(SD_SPI, Data);
  
  /*!< Wait to receive a byte*/
  while(SPI_I2S_GetFlagStatus(SD_SPI, SPI_I2S_FLAG_RXNE) == RESET)
  {
  }
  
  /*!< Return the byte read from the SPI bus */ 
  return SPI_I2S_ReceiveData(SD_SPI);
}

/**
  * @brief  Read a byte from the SD.
  * @param  None
  * @retval The received byte.
  */
uint8_t SD_ReadByte(void)
{
  uint8_t Data = 0;
  
  /*!< Wait until the transmit buffer is empty */
  while (SPI_I2S_GetFlagStatus(SD_SPI, SPI_I2S_FLAG_TXE) == RESET)
  {
  }
  /*!< Send the byte */
  SPI_I2S_SendData(SD_SPI, SD_DUMMY_BYTE);

  /*!< Wait until a data is received */
  while (SPI_I2S_GetFlagStatus(SD_SPI, SPI_I2S_FLAG_RXNE) == RESET)
  {
  }
  /*!< Get the received data */
  Data = SPI_I2S_ReceiveData(SD_SPI);

  /*!< Return the shifted data */
  return Data;
}

/**
  * @}
  */


/**
  * @}
  */


/**
  * @}
  */

/**
  * @}
  */

/**
  * @}
  */  

/******************* (C) COPYRIGHT 2011 STMicroelectronics *****END OF FILE****/