/**
  ******************************************************************************
  * @file    stm320518_eval_spi_sd.c
  * @author  MCD Application Team
  * @version V1.1.1
  * @date    16-January-2014
  * @brief   This file provides a set of functions needed to manage the SPI SD 
  *          Card memory mounted on STM320518-EVAL board.
  *          It implements a high level communication layer for read and write 
  *          from/to this memory. The needed STM32F0xx hardware resources (SPI and 
  *          GPIO) are defined in stm320518_eval.h file, and the initialization is 
  *          performed in SD_LowLevel_Init() function declared in stm320518_eval.c 
  *          file.
  *          You can easily tailor this driver to any other development board, 
  *          by just adapting the defines for hardware resources and 
  *          SD_LowLevel_Init() function.
  *
  *          ===================================================================
  *          Notes: 
  *           - This driver is intended for STM32F0xx families devices only.
  *           - This driver doesn't support SD High Capacity cards.
  *          ===================================================================
  *
  *          +-------------------------------------------------------+
  *          |                     Pin assignment                    |
  *          +-------------------------+---------------+-------------+
  *          |  STM32F0xx SPI Pins     |     SD        |    Pin      |
  *          +-------------------------+---------------+-------------+
  *          | SD_SPI_CS_PIN           |   ChipSelect  |    1        |
  *          | SD_SPI_MOSI_PIN / MOSI  |   DataIn      |    2        |
  *          |                         |   GND         |    3 (0 V)  |
  *          |                         |   VDD         |    4 (3.3 V)|
  *          | SD_SPI_SCK_PIN / SCLK   |   Clock       |    5        |
  *          |                         |   GND         |    6 (0 V)  |
  *          | SD_SPI_MISO_PIN / MISO  |   DataOut     |    7        |
  *          +-------------------------+---------------+-------------+
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT 2014 STMicroelectronics</center></h2>
  *
  * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
  * You may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
  *
  *        http://www.st.com/software_license_agreement_liberty_v2
  *
  * Unless required by applicable law or agreed to in writing, software 
  * distributed under the License is distributed on an "AS IS" BASIS, 
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  *
  ******************************************************************************
  */

/* Includes ------------------------------------------------------------------*/
#include "stm320518_eval_spi_sd.h"

/** @addtogroup Utilities
  * @{
  */
  
/** @addtogroup STM32_EVAL
  * @{
  */

/** @addtogroup STM320518_EVAL
  * @{
  */

/** @addtogroup STM320518_EVAL_SPI_SD
  * @brief      This file includes the SD card driver of STM320518-EVAL boards.
  * @{
  */ 

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/

/** @defgroup STM320518_EVAL_SPI_SD_Private_Variables
  * @{
  */ 

/**
  * @}
  */ 


/** @defgroup STM320518_EVAL_SPI_SD_Private_Function_Prototypes
  * @{
  */
/**
  * @}
  */ 


/** @defgroup STM320518_EVAL_SPI_SD_Private_Functions
  * @{
  */ 

/**
  * @brief  DeInitializes the SD/SD communication.
  * @param  None
  * @retval None
  */
void SD_DeInit(void)
{
  SD_LowLevel_DeInit();
}

/**
  * @brief  Initializes the SD/SD communication.
  * @param  None
  * @retval The SD Response: 
  *         - SD_RESPONSE_FAILURE: Sequence failed
  *         - SD_RESPONSE_NO_ERROR: Sequence succeed
  */
SD_Error SD_Init(void)
{
  uint32_t i = 0;

  /* Initialize SD_SPI */
  SD_LowLevel_Init(); 

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

  /* Send dummy byte 0xFF, 10 times with CS high */
  /* Rise CS and MOSI for 80 clocks cycles */
  for (i = 0; i <= 9; i++)
  {
    /* Send dummy byte 0xFF */
    SD_WriteByte(SD_DUMMY_BYTE);
  }
  
  /*------------Put SD in SPI mode--------------*/
  /* SD initialized and set to SPI mode properly */
  return (SD_GoIdleState());
}

/**
 * @brief  Detect if SD card is correctly plugged in the memory slot.
 * @param  None
 * @retval Return if SD is detected or not
 */
uint8_t SD_Detect(void)
{
  __IO uint8_t status = SD_PRESENT;

  /* Check GPIO to detect SD */
  if (GPIO_ReadInputData(SD_DETECT_GPIO_PORT) & SD_DETECT_PIN)
  {
    status = SD_NOT_PRESENT;
  }
  return status;
}

/**
  * @brief  Returns information about specific card.
  * @param  cardinfo: pointer to a SD_CardInfo structure that contains all SD 
  *         card information.
  * @retval The SD Response:
  *         - SD_RESPONSE_FAILURE: Sequence failed
  *         - SD_RESPONSE_NO_ERROR: Sequence succeed
  */
SD_Error SD_GetCardInfo(SD_CardInfo *cardinfo)
{
  SD_Error status = SD_RESPONSE_FAILURE;

  SD_GetCSDRegister(&(cardinfo->SD_csd));
  status = SD_GetCIDRegister(&(cardinfo->SD_cid));
  cardinfo->CardCapacity = (cardinfo->SD_csd.DeviceSize + 1) ;
  cardinfo->CardCapacity *= (1 << (cardinfo->SD_csd.DeviceSizeMul + 2));
  cardinfo->CardBlockSize = 1 << (cardinfo->SD_csd.RdBlockLen);
  cardinfo->CardCapacity *= cardinfo->CardBlockSize;

  /* Returns the reponse */
  return status;
}

/**
  * @brief  Reads a block of data from the SD.
  * @param  pBuffer: pointer to the buffer that receives the data read from the SD card.
  * @param  ReadAddr: SD's internal address to read from.
  * @param  BlockSize: the SD card Data block size.
  * @retval The SD Response:
  *         - SD_RESPONSE_FAILURE: Sequence failed
  *         - SD_RESPONSE_NO_ERROR: Sequence succeed
  */
SD_Error SD_ReadBlock(uint8_t* pBuffer, uint32_t ReadAddr, uint16_t BlockSize)
{
  uint32_t i = 0;
  SD_Error rvalue = SD_RESPONSE_FAILURE;
  
  /* SD chip select low */
  SD_CS_LOW();
  
  /* Send CMD17 (SD_CMD_READ_SINGLE_BLOCK) to read one block */
  SD_SendCmd(SD_CMD_READ_SINGLE_BLOCK, ReadAddr, 0xFF);
  
  /* Check if the SD acknowledged the read block command: R1 response (0x00: no errors) */
  if (!SD_GetResponse(SD_RESPONSE_NO_ERROR))
  {
    /* Now look for the data token to signify the start of the data */
    if (!SD_GetResponse(SD_START_DATA_SINGLE_BLOCK_READ))
    {
      /* Read the SD block data : read NumByteToRead data */
      for (i = 0; i < BlockSize; i++)
      {
        /* Save the received data */
        *pBuffer = SD_ReadByte();
       
        /* Point to the next location where the byte read will be saved */
        pBuffer++;
      }
      /* Get CRC bytes (not really needed by us, but required by SD) */
      SD_ReadByte();
      SD_ReadByte();
      /* 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);
  
  /* Returns the response */
  return rvalue;
}

/**
  * @brief  Reads multiple block of data from the SD.
  * @param  pBuffer: pointer to the buffer that receives the data read from the SD card.
  * @param  ReadAddr: SD's internal address to read from.
  * @param  BlockSize: the SD card Data block size.
  * @param  NumberOfBlocks: number of blocks to be read.
  * @retval The SD Response:
  *         - SD_RESPONSE_FAILURE: Sequence failed
  *         - SD_RESPONSE_NO_ERROR: Sequence succeed
  */
SD_Error SD_ReadMultiBlocks(uint8_t* pBuffer, uint32_t ReadAddr, uint16_t BlockSize, uint32_t NumberOfBlocks)
{
  uint32_t i = 0, Offset = 0;
  SD_Error rvalue = SD_RESPONSE_FAILURE;
  
  /* SD chip select low */
  SD_CS_LOW();
  /* Data transfer */
  while (NumberOfBlocks--)
  {
    /* Send CMD17 (SD_CMD_READ_SINGLE_BLOCK) to read one block */
    SD_SendCmd (SD_CMD_READ_SINGLE_BLOCK, ReadAddr + Offset, 0xFF);
    /* Check if the SD acknowledged the read block command: R1 response (0x00: no errors) */
    if (SD_GetResponse(SD_RESPONSE_NO_ERROR))
    {
      return  SD_RESPONSE_FAILURE;
    }
    /* Now look for the data token to signify the start of the data */
    if (!SD_GetResponse(SD_START_DATA_SINGLE_BLOCK_READ))
    {
      /* Read the SD block data : read NumByteToRead data */
      for (i = 0; i < BlockSize; i++)
      {
        /* Read the pointed data */
        *pBuffer = SD_ReadByte();
        /* Point to the next location where the byte read will be saved */
        pBuffer++;
      }
      /* Set next read address*/
      Offset += 512;
      /* get CRC bytes (not really needed by us, but required by SD) */
      SD_ReadByte();
      SD_ReadByte();
      /* Set response value to success */
      rvalue = SD_RESPONSE_NO_ERROR;
    }
    else
    {
      /* Set response value to failure */
      rvalue = SD_RESPONSE_FAILURE;
    }
  }
  /* SD chip select high */
  SD_CS_HIGH();
  /* Send dummy byte: 8 Clock pulses of delay */
  SD_WriteByte(SD_DUMMY_BYTE);
  /* Returns the response */
  return rvalue;
}

/**
  * @brief  Writes a block on the SD
  * @param  pBuffer: pointer to the buffer containing the data to be written on
  *         the SD card.
  * @param  WriteAddr: address to write on.
  * @param  BlockSize: the SD card Data block size.
  * @retval The SD Response: 
  *         - SD_RESPONSE_FAILURE: Sequence failed
  *         - SD_RESPONSE_NO_ERROR: Sequence succeed
  */
SD_Error SD_WriteBlock(uint8_t* pBuffer, uint32_t WriteAddr, uint16_t BlockSize)
{
  uint32_t i = 0;
  SD_Error rvalue = SD_RESPONSE_FAILURE;

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

  /* Send CMD24 (SD_CMD_WRITE_SINGLE_BLOCK) to write multiple block */
  SD_SendCmd(SD_CMD_WRITE_SINGLE_BLOCK, WriteAddr, 0xFF);
  
  /* Check if the SD acknowledged the write block command: R1 response (0x00: no errors) */
  if (!SD_GetResponse(SD_RESPONSE_NO_ERROR))
  {
    /* Send a dummy byte */
    SD_WriteByte(SD_DUMMY_BYTE);

    /* Send the data token to signify the start of the data */
    SD_WriteByte(0xFE);

    /* Write the block data to SD : write count data by block */
    for (i = 0; i < BlockSize; i++)
    {
      /* Send the pointed byte */
      SD_WriteByte(*pBuffer);
      /* Point to the next location where the byte read will be saved */
      pBuffer++;
    }
    /* Put CRC bytes (not really needed by us, but required by SD) */
    SD_ReadByte();
    SD_ReadByte();
    /* Read data response */
    if (SD_GetDataResponse() == SD_DATA_OK)
    {
      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);

  /* Returns the response */
  return rvalue;
}

/**
  * @brief  Writes many blocks on the SD
  * @param  pBuffer: pointer to the buffer containing the data to be written on 
  *         the SD card.
  * @param  WriteAddr: address to write on.
  * @param  BlockSize: the SD card Data block size.
  * @param  NumberOfBlocks: number of blocks to be written.
  * @retval The SD Response: 
  *         - SD_RESPONSE_FAILURE: Sequence failed
  *         - SD_RESPONSE_NO_ERROR: Sequence succeed
  */
SD_Error SD_WriteMultiBlocks(uint8_t* pBuffer, uint32_t WriteAddr, uint16_t BlockSize, uint32_t NumberOfBlocks)
{
  uint32_t i = 0, Offset = 0;
  SD_Error rvalue = SD_RESPONSE_FAILURE;

  /* SD chip select low */
  SD_CS_LOW();
  /* Data transfer */
  while (NumberOfBlocks--)
  {
    /* Send CMD24 (SD_CMD_WRITE_SINGLE_BLOCK) to write blocks */
    SD_SendCmd(SD_CMD_WRITE_SINGLE_BLOCK, WriteAddr + Offset, 0xFF);
    /* Check if the SD acknowledged the write block command: R1 response (0x00: no errors) */
    if (SD_GetResponse(SD_RESPONSE_NO_ERROR))
    {
      return SD_RESPONSE_FAILURE;
    }
    /* Send dummy byte */
    SD_WriteByte(SD_DUMMY_BYTE);
    /* Send the data token to signify the start of the data */
    SD_WriteByte(SD_START_DATA_SINGLE_BLOCK_WRITE);
    /* Write the block data to SD : write count data by block */
    for (i = 0; i < BlockSize; i++)
    {
      /* Send the pointed byte */
      SD_WriteByte(*pBuffer);
      /* Point to the next location where the byte read will be saved */
      pBuffer++;
    }
    /* Set next write address */
    Offset += 512;
    /* Put CRC bytes (not really needed by us, but required by SD) */
    SD_ReadByte();
    SD_ReadByte();
    /* Read data response */
    if (SD_GetDataResponse() == SD_DATA_OK)
    {
      /* Set response value to success */
      rvalue = SD_RESPONSE_NO_ERROR;
    }
    else
    {
      /* Set response value to failure */
      rvalue = SD_RESPONSE_FAILURE;
    }
  }
  /* SD chip select high */
  SD_CS_HIGH();
  /* Send dummy byte: 8 Clock pulses of delay */
  SD_WriteByte(SD_DUMMY_BYTE);
  /* Returns the response */
  return rvalue;
}

/**
  * @brief  Read the CSD card register.
  * @note   Reading the contents of the CSD register in SPI mode is a simple 
  *         read-block transaction.
  * @param  SD_csd: pointer on an SCD register structure
  * @retval The SD Response: 
  *         - SD_RESPONSE_FAILURE: Sequence failed
  *         - SD_RESPONSE_NO_ERROR: Sequence succeed
  */
SD_Error SD_GetCSDRegister(SD_CSD* SD_csd)
{
  uint32_t i = 0;
  SD_Error rvalue = SD_RESPONSE_FAILURE;
  uint8_t CSD_Tab[16];

  /* SD chip select low */
  SD_CS_LOW();
  /* Send CMD9 (CSD register) or CMD10(CSD register) */
  SD_SendCmd(SD_CMD_SEND_CSD, 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))
    {
      for (i = 0; i < 16; i++)
      {
        /* Store CSD register value on CSD_Tab */
        CSD_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_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 response */
  return rvalue;
}

/**
  * @brief  Read the CID card register.
  * @note   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 response */
  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 accepted
  *         - 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 response */
    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 failure */
    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_SendData8(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_ReceiveData8(SD_SPI);
}

/**
  * @brief  Read a byte from the SD.
  * @param  None
  * @retval The received byte.
  */
uint8_t SD_ReadByte(void)
{
  /* Wait until the transmit buffer is empty */
  while (SPI_I2S_GetFlagStatus(SD_SPI, SPI_I2S_FLAG_TXE) == RESET)
  {
  }
  /* Send the byte */
  SPI_SendData8(SD_SPI, SD_DUMMY_BYTE);

  /* Wait until a data is received */
  while (SPI_I2S_GetFlagStatus(SD_SPI, SPI_I2S_FLAG_RXNE) == RESET)
  {
  }

  /* Return the shifted data */
  return SPI_ReceiveData8(SD_SPI);;
}

/**
  * @}
  */


/**
  * @}
  */


/**
  * @}
  */

/**
  * @}
  */

/**
  * @}
  */

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