*********************************************************************************************************************/
#if SD_WriteMultiBlock_EN
INT8U SD_GetNumWRBlcoks(INT32U *blocknum)
{
    INT8U tmp[4] = {0,0,0,0},resp,ret;
  
    ret = SD_SendCmd(CMD55, tmp, CMD55_R, &resp);	  			/* 后續(xù)命令為一個(gè)應(yīng)用命令 */
    if (ret != SD_NO_ERR) 										/* command that the followed commnad is a specific application */
    	return ret;
    	 
    if (resp != 0)
    	return SD_ERR_CMD_RESP;    	
 											
   	ret = SD_SendCmd(ACMD22, tmp, ACMD22_R, &resp);  			/* 讀取正確寫入的塊數(shù)命令 */
   	if (ret != SD_NO_ERR)										/* command that read the numbers of block written correctly */
   		return ret;											    
   		 														
	if (resp != 0)
    	return SD_ERR_CMD_RESP;									/* 響應(yīng)錯(cuò)誤 response is error */
    		
    ret = SD_ReadBlockData(4, tmp);								/* 讀塊數(shù) read the numbvers of block */
    if (ret != SD_NO_ERR)
    	return ret;
    	
    *blocknum = (tmp[0] << 24) + (tmp[1] << 16) + (tmp[2] << 8) + tmp[3];	
    															/* 轉(zhuǎn)換為32位 change to 32 bits */

	return SD_NO_ERR;    										/* 返回執(zhí)行成功 return perform sucessfully */		
}
#endif

		/*********************************************************
		
		    			下面為一些數(shù)據(jù)傳輸函數(shù)
		
		**********************************************************/

/********************************************************************************************************************
** 函數(shù)名稱: INT8U SD_ReadRegister()				Name:	  INT8U SD_ReadRegister()
** 功能描述: 從SD卡讀取數(shù)據(jù)							Function: read data from SD card
** 輸　  入: INT32U len	  : 長度					Input:	  INT32U len   : length
			 INT8U *recbuf: 接收緩沖區(qū)					 	  INT8U *recbuf: receive buffer
** 輸 　 出: 0:   正確    >0:   錯(cuò)誤碼		  		Output:	  0:  right		>0:  error code
*********************************************************************************************************************/
INT8U SD_ReadRegister(INT32U len, INT8U *recbuf)
{	
	INT32U i = 0;
	INT8U resp;

    SPI_CS_Assert();
    do{    											/* 等待數(shù)據(jù)起始令牌 wait for data start token */
        resp = SPI_RecByte();
    	i++;
    }while((resp == 0xFF) && (i < SD_READREG_TIMEOUT));    
    
    if (i >= SD_READREG_TIMEOUT)
    {
    	SPI_CS_Deassert();
    	return SD_ERR_TIMEOUT_READ;					/* 超時(shí), 返回錯(cuò)誤 timeout, return error */
  	}
  	
   	if (resp != SD_TOK_READ_STARTBLOCK)				
   	{												/* 不是收到數(shù)據(jù)起始令牌 not receive data start token */
		recbuf[0] = resp;							
		i = 1;										/* 還有l(wèi)en - 1個(gè)字節(jié)要接收 still len - 1 bytes will be received */
   	}
   	else
   		i = 0;										/* 收到數(shù)據(jù)起始令牌,還有l(wèi)en個(gè)字節(jié)要接收 received data start token,still len bytes will be received */
   	  	
    for (; i < len; i++)
   		recbuf[i] = SPI_RecByte();					/* 接收數(shù)據(jù) receive data */
   		
    i = SPI_RecByte();								
    i = (i << 8) + SPI_RecByte();    				/* 讀取16位CRC get 16-bit CRC */	

#if SD_CRC_EN 
   	if (i != SD_GetCRC16(recbuf, len))
   	{												/* CRC校驗(yàn)錯(cuò)誤 CRC check is error */
   		SPI_CS_Deassert();
   		SPI_SendByte(0xFF);    						
  		return SD_ERR_DATA_CRC16;					/* 返回RCR16錯(cuò)誤  return error of CRC16 */				
  	}    
#endif   
  
    SPI_SendByte(0xFF);								/* 返回之前發(fā)送8個(gè)clock  clock out 8 clk before return */
    SPI_CS_Deassert();	
    	
	return SD_NO_ERR;
}	

/*******************************************************************************************************************
** 函數(shù)名稱: INT8U SD_ReadBlockData()			Name:	  INT8U SD_ReadBlockData()
** 功能描述: 從SD卡中讀取數(shù)據(jù)塊					Function: read block data from sd card
** 輸　  入: INT32U len    : 長度				Input:	  INT32U len    : length
			 INT8U *recbuf : 接收緩沖區(qū)					  INT8U *recbuf : the buffer of receive
** 輸 　 出: 0:   正確    >0:   錯(cuò)誤碼		  	Output:	  0:  right		>0:  error code
*******************************************************************************************************************/
INT8U SD_ReadBlockData(INT32U len, INT8U *recbuf)
{
    INT8U tmp;
    INT32U i = 0;
    
    SPI_CS_Assert();    
    do
    { 											    /* 等待接收數(shù)據(jù)開始令牌0xFE  wait for receiving data start token 0xFE */
        tmp = SPI_RecByte();
        i++;
     }while((tmp == 0xFF) && (i < sds.timeout_read));
	
	if (i >= sds.timeout_read)
	{
		SPI_CS_Deassert();
       	return SD_ERR_TIMEOUT_READ;					/* 返回讀超時(shí)錯(cuò)誤碼  return error timeout error code of reading */
	}
		
	if (tmp != SD_TOK_READ_STARTBLOCK)				/* 塊讀開始令牌錯(cuò)誤 read start block token is error */
	{
		SPI_SendByte(0xFF);
		SPI_CS_Deassert();
		return SD_ERR_DATA_START_TOK;
	}
	
	for (i = 0; i < len; i++)
   		recbuf[i] = SPI_RecByte();					/* 接收數(shù)據(jù) receive data */
   		
    i = SPI_RecByte();								
    i = (i << 8) + SPI_RecByte();    				/* 讀取16位CRC get 16-bit CRC */	

#if SD_CRC_EN 
   	if (i != SD_GetCRC16(recbuf, len))
   	{												/* CRC校驗(yàn)錯(cuò)誤 CRC check is error */
   		SPI_SendByte(0xFF); 
   		SPI_CS_Deassert();  						
  		return SD_ERR_DATA_CRC16;					/* 返回CRC16錯(cuò)誤  return error of CRC16 */				
  	}    
#endif   

	SPI_SendByte(0xFF); 
	SPI_CS_Deassert();

  	return SD_NO_ERR;								/* 返回函數(shù)執(zhí)行成功 return function perform sucessfully */
}

/*******************************************************************************************************************
** 函數(shù)名稱: INT8U SD_WriteBlockData()				Name:	  INT8U SD_WriteBlockData()
** 功能描述: 向sd卡寫數(shù)據(jù)塊							Function: write block data to sd card
** 輸　  入: INT8U bmulti  : 是否為多塊操作1:是0:否 Input:	  INT8U bmulti   : multi blocks operate 1:Y 0:N 
			 INT32U len    : 長度						  	  INT32U len     : length
			 INT8U *sendbuf: 發(fā)送緩沖區(qū)					 	  INT8U *sendbuf : the buffer of send
** 輸 　 出: 0:   正確    >0:   錯(cuò)誤碼		  		Output:	  0:  right		>0:  error code
********************************************************************************************************************/
INT8U SD_WriteBlockData(INT8U bmulti, INT32U len, INT8U *sendbuf)
{
	INT16U i;
	INT8U tmp;

	SPI_CS_Assert();
		
    SPI_SendByte(0xFF);								/* 開始發(fā)送數(shù)據(jù)之前發(fā)送8個(gè)clock clock out 8 clk before start */
    
    if (bmulti == 1)
        SPI_SendByte(SD_TOK_WRITE_STARTBLOCK_M);	/* 寫多塊開始令牌 start token of write multi blocks */
	else
		SPI_SendByte(SD_TOK_WRITE_STARTBLOCK);		/* 寫單塊開始令牌 start token of write single block */

	for (i = 0; i < len; i++)
        SPI_SendByte(sendbuf[i]);					/* 發(fā)送數(shù)據(jù) send data */

#if SD_CRC_EN	
	i = SD_GetCRC16(sendbuf,len);					/* 計(jì)算CRC16 calculate CRC16 */
#endif

	SPI_SendByte((i >> 8) & 0xFF);
	SPI_SendByte(i & 0xFF); 						/* 發(fā)送CRC16校驗(yàn)碼 send CRC16 check code */
			    
	tmp = SPI_RecByte();
  	if ((tmp & SD_RESP_DATA_MSK) != SD_RESP_DATA_ACCETPTED)	
  	{		
   		SPI_SendByte(0xFF);							/* 返回之前發(fā)送8個(gè)clock  clock out 8 clk before return */
   		SPI_CS_Deassert();
   		return SD_ERR_DATA_RESP;					/* 數(shù)據(jù)響應(yīng)錯(cuò)誤 data response error */
    }
        
    SPI_CS_Deassert();
     		
    if (SD_WaitBusy(SD_WAIT_WRITE) != SD_NO_ERR)			
    	return SD_ERR_TIMEOUT_WRITE;				/* 寫入超時(shí) write time out */
    else
    	return SD_NO_ERR; 							/* 寫入正確 write right */
 }

/*******************************************************************************************************************
** 函數(shù)名稱: void SD_StopMultiToken()				Name:	  void SD_StopMultiToken(void)
** 功能描述: 發(fā)送多塊寫停止令牌						Function: send the token that stop multiple block write
** 輸　  入: 無									    Input:	  NULL
** 輸 　 出: 無										Output:	  NULL
********************************************************************************************************************/
void SD_StopMultiToken(void)
{
	SPI_CS_Assert();
	
	SPI_SendByte(0xFF);								/* 先發(fā)送8個(gè)clock send 8 clock first */
	SPI_SendByte(SD_TOK_STOP_MULTI);				/* 發(fā)送停止數(shù)據(jù)傳輸令牌 send stop transmission token */
	SPI_RecByte();
	
    SPI_CS_Deassert();
}


/********************************************************************************************************************
** 函數(shù)名稱: void SD_WaitBusy()						Name:	  void SD_WaitBusy()
** 功能描述: 查詢SD卡是否處于忙狀態(tài)					Function: poll SD Card wheather it is busy
** 輸　  入: INT32U waittype: 超時(shí)類型				Input:	  INT32U timeout: time out type
** 輸 　 出: 0: 未超時(shí)  >0: 錯(cuò)誤碼					Output:	  0: not time out   > 0: error code
*********************************************************************************************************************/
INT8U SD_WaitBusy(INT8U waittype)
{
    INT32U timeout, i = 0;
    INT8U tmp;
    
    if (waittype == SD_WAIT_WRITE)
    	timeout = sds.timeout_write;
    else
    	timeout = sds.timeout_erase;

	SPI_CS_Assert();
   	do
   	{ 												/* 等待忙結(jié)束 wait for being busy end */
        tmp = SPI_RecByte();
        i++;
    }while ((tmp != 0xFF) && (i < timeout));		/* 忙時(shí)收到的值為0xFF always receive 0xFF when card is busy */    
	SPI_CS_Deassert();								/* 有錯(cuò) */
	
	if(i < timeout) 
		return SD_NO_ERR;							/* 返回0,表示沒超時(shí) return 0 indicate that operation is not time out */
	else 
		return SD_ERR_TIMEOUT_WAIT;					/* 返回錯(cuò)誤碼,表示超時(shí) return error code indicate that operation is time out */
}

/********************************************************************************************************************
** 函數(shù)名稱: void SD_SPIDelay()						Name:	  void SD_SPIDelay()
** 功能描述: SPI總線延時(shí)							Function: SPI Bus delay 
** 輸　  入: INT8U value: 延時(shí)值,不超過255		    Input:	  INT8U value : delay value,do not beyond 255
** 輸 　 出: 無										Output:	  NULL
*********************************************************************************************************************/
void SD_SPIDelay(INT8U value)
{
    INT8U i;

    for (i = 0; i < value; i++)
        SPI_SendByte(0xFF);						 	/* 發(fā)送0xFF clock out 0xFF */
}