sdcmd.c

周立功公司为LPC213X ARM7 编写的SD卡读写模块

/****************************************Copyright (c)**************************************************
**                               Guangzhou ZLG-MCU Development Co.,LTD.
**                                      graduate school
**                                 http://www.zlgmcu.com
**
**--------------File Info-------------------------------------------------------------------------------
** File name:			sddriver.c
** Last modified Date:	2005-1-6
** Last Version:		V1.0
** Descriptions:		sd 卡驱动软件包: SD卡物理层 ---- SD卡SPI模式支持的命令 
**						Soft Packet of SD Card Driver: commands that sd card supported in spi mode
**
**------------------------------------------------------------------------------------------------------
** Created by:			Ming Yuan Zheng
** Created date:		2005-1-6
** Version:				V1.0
** Descriptions:		The original version
**
**------------------------------------------------------------------------------------------------------
** Modified by:			
** Modified date:		
** Version:				
** Descriptions:		
**
**------------------------------------------------------------------------------------------------------
** Modified by: 
** Modified date:
** Version:	
** Descriptions: 
**
********************************************************************************************************/

#include "config.h"
#include "sdconfig.h"
#include "sdhal.h"
#include "sdcrc.h"
#include "sdcmd.h"
#include "sddriver.h"

/********************************************************************************************************************
** 函数名称: INT8U SD_SendCmd()						Name:	  INT8U SD_SendCmd()
** 功能描述: 向卡发送命令,并取得响应				Function: send command to the card,and get a response
** 输　  入: INT8U cmd	    : 命令字				Input:	  INT8U cmd	    : command byte	
			 INT8U *param	: 命令参数,长度为4字节			  INT8U *param	: command parameter,length is 4 bytes  
			 INT8U resptype : 响应类型						  INT8U resptype: response type
			 INT8U *resp	: 响应,长度为1-5字节			  INT8U *resp	: response,length is 1-5 bytes
** 输 　 出: 0:   正确    >0:   错误码		  		Output:	  0:  right		>0:  error code
********************************************************************************************************************/
INT8U SD_SendCmd(INT8U cmd, INT8U *param, INT8U resptype, INT8U *resp)
{
	INT32 i,rlen;
	INT8U tmp;
    
	SPI_CS_Assert();
   
    SPI_SendByte((cmd & 0x3F) | 0x40);				 /* 发送命令头和命令字 send command header and word */
    
    for (i = 3; i >= 0; i--)
        SPI_SendByte(param[i]);						 /* 发送参数 send parameters */

#if SD_CRC_EN
	tmp = SD_GetCmdByte6((cmd & 0x3F) | 0x40, param);
	SPI_SendByte(tmp);
#else
    SPI_SendByte(0x95);							 	 /* CRC校验码,只用于第1个命令 CRC,only used for the first command */
#endif 
    
    rlen = 0;
    switch (resptype)								 /* 根据不同的命令,得到不同的响应长度 */
    {												 /* according various command,get the various response length */
  		case R1:
   	 	case R1B: rlen = 1;  break;
       		 
    	case R2:  rlen = 2;	 break;
       		 
   		case R3:  rlen = 5;	 break;
       		 
    	default:  SPI_SendByte(0xFF);	
      		      SPI_CS_Deassert();						 
        	      return SD_ERR_CMD_RESPTYPE;		 /* 返回命令响应类型错误 return error of command response type */
    		      break;
    }
    
    i = 0;				
    do 												 /* 等待响应,响应的开始位为0 */
    {												 /* Wait for a response,a response is a start bit(zero) */ 
        tmp = SPI_RecByte();
        i++;
    }while (((tmp & 0x80) != 0) && (i < SD_CMD_TIMEOUT));
    
    if (i >= SD_CMD_TIMEOUT)
    {												 
        SPI_CS_Deassert();
        return SD_ERR_CMD_TIMEOUT;					 /* 返回命令超时 return response timeout of command */
    }
    
    for (i = rlen - 1; i >= 0; i--)
    {
        resp[i] = tmp;
        tmp = SPI_RecByte();					 	 /* 循环的最后发送8clock  at the last recycle,clock out 8 clock */
    }
      
    SPI_CS_Deassert();
    return SD_NO_ERR;								 /* 返回执行成功 return perform sucessfully */
}

/********************************************************************************************************************
** 函数名称: void SD_PackParam()					Name:	  void SD_PackParam()
** 功能描述: 将32位的参数转为字节形式				Function: change 32bit parameter to bytes form 
** 输　  入: INT8U *parameter: 字节参数缓冲区		Input:	  INT8U *parameter: the buffer of bytes parameter
			 INT32U value    : 32位参数						  INT32U value    : 32bit parameter
** 输 　 出: 无										Output:	  NULL
*********************************************************************************************************************/
void SD_PackParam(INT8U *parameter, INT32U value)
{
    parameter[3] = (INT8U)(value >> 24);
    parameter[2] = (INT8U)(value >> 16);
    parameter[1] = (INT8U)(value >> 8);
    parameter[0] = (INT8U)(value);
}

/********************************************************************************************************************
** 函数名称: INT8U SD_BlockCommand()				Name:	  INT8U SD_BlockCommand()
** 功能描述: 块命令									Function: command about block operation
** 输　  入: INT8U cmd	     : 命令字				Input:	  INT8U cmd	      : command byte 
			 INT8U resptype  : 响应类型						  INT8U resptype  : response type
			 INT32U parameter: 块操作参数			 		  INT32U parameter: parameter of block operation
** 输 　 出: 0:   正确    >0:   错误码		  		Output:	  0:  right		>0:  error code
*********************************************************************************************************************/
INT8U SD_BlockCommand(INT8U cmd, INT8U resptype, INT32U parameter)
{
	INT8U param[4],resp,ret;
	
	parameter <<= SD_BLOCKSIZE_NBITS;					 /* 调整地址:左移9位 adjust address: move 9 bits left */

	SD_PackParam(param, parameter);						 /* 将参数转化为字节形式 change the parameter to bytes form */	

	ret = SD_SendCmd(cmd, param, resptype, &resp);
	if (ret != SD_NO_ERR)
	   	 return ret;							 		 /* 结束数据传输失败 stop transmission operation fail */
	
	if (resp != 0)
		 return SD_ERR_CMD_RESP;		 				 /* 响应错误 response is error */
		 
	return SD_NO_ERR;
}

	/*
	************************************************
	
	 	下面为SD卡SPI命令

	************************************************
	*/
	
/********************************************************************************************************************
** 函数名称: INT8U SD_ResetSD()						Name:	  INT8U SD_ResetSD()
** 功能描述: 复位SD卡								Function: reset sd card
** 输　  入: 无										Input:	  NULL
** 输 　 出: 0:   正确    >0:   错误码		  		Output:	  0:  right		>0:  error code
*********************************************************************************************************************/
INT8U SD_ResetSD(void)
{
	INT8U param[4] = {0,0,0,0},resp;
	
    return (SD_SendCmd(CMD0, param, CMD0_R, &resp));	/* 复位命令 command that reset sd card */
}

/********************************************************************************************************************
** 函数名称: INT8U SD_ReadCSD()						Name:	  INT8U SD_ReadCSD()
** 功能描述: 读SD卡的CSD寄存器						Function: read CSD register of sd card 
** 输　  入: INT8U csdlen  : 寄存器长度(固定为16)			  INT8U csdlen  : len of register (fixed,is 16)
			 INT8U *recbuf : 接收缓冲区					      INT8U *recbuf : recbuffer	
** 输 　 出: 0:   正确    >0:   错误码		  		Output:	  0:  right		>0:  error code
*********************************************************************************************************************/
INT8U SD_ReadCSD(INT8U csdlen, INT8U *recbuf)
{
    INT8U param[4] = {0,0,0,0},resp,ret;
  
    ret = SD_SendCmd(CMD9, param, CMD9_R, &resp);		/* 读CSD寄存器命令 command that read CSD register */
    if (ret != SD_NO_ERR) 									
        return ret;									
  
    if (resp != 0)
        return SD_ERR_CMD_RESP;							/* 响应错误 response is error */
    
	return (SD_ReadRegister(csdlen, recbuf));
}

/*******************************************************************************************************************
** 函数名称: INT8U SD_ReadCID()						Name:	  INT8U SD_ReadCID()
** 功能描述: 读SD卡的CID寄存器						Function: read CID register of sd card
** 输　  入: INT8U cidlen  : 寄存器长度(固定为16)			  INT8U cidlen  : len of register (fixed,is 16)
			 INT8U *recbuf : 接收缓冲区					      INT8U *recbuf : recbuffer	
** 输 　 出: 0:   正确    >0:   错误码		  		Output:	  0:  right		>0:  error code
********************************************************************************************************************/
#if SD_ReadCID_EN
INT8U SD_ReadCID(INT8U cidlen, INT8U *recbuf)
{
    INT8U param[4] = {0,0,0,0},resp,ret;
 
    ret = SD_SendCmd(CMD10, param, CMD10_R, &resp);		/* 读CID寄存器命令 command that read CID register */
    if ( ret != SD_NO_ERR)
   		return ret;			  									
   
    if (resp != 0)
        return SD_ERR_CMD_RESP;							/* 响应错误 response is error */
      
  	return (SD_ReadRegister(cidlen, recbuf));
}
#endif

/********************************************************************************************************************
** 函数名称: INT8U SD_StopTransmission()			Name:	  INT8U SD_StopTransmission()
** 功能描述: 停止数据传输							Function: stop data transmission 
** 输　  入: 无								 		Input:    NULL
** 输 　 出: 0:   正确    >0:   错误码		  		Output:	  0:  right		>0:  error code
*********************************************************************************************************************/
INT8U SD_StopTransmission(void)
{
	INT8U param[4] = {0,0,0,0},resp;
	
 	return (SD_SendCmd(CMD12, param, CMD12_R, &resp));	/* 结束数据传输命令失败 stop transmission command fail */
}

/*********************************************************************************************************************
** 函数名称: INT8U SD_ReadCard_Status()				Name:	  INT8U SD_ReadCard_Status()
** 功能描述: 读SD卡的 Card Status 寄存器			Function: read Card Status register of sd card 
** 输　  入: INT8U len: 	 寄存器长度(固定为2)			  INT8U len:      len of register (fixed,is 2)
			 INT8U *recbuf : 接收缓冲区					      INT8U *recbuf : recbuffer
** 输 　 出: 0:   正确    >0:   错误码		  		Output:	  0:  right		>0:  error code
**********************************************************************************************************************/
INT8U SD_ReadCard_Status(INT8U len, INT8U *buffer)
{
    INT8U param[4] = {0,0,0,0};

    return (SD_SendCmd(CMD13, param, CMD13_R, buffer)); /* 读 Card Status 寄存器 */
    									 	 			/* read register of Card Status */
}


/********************************************************************************************************************
** 函数名称: INT8U Sd_SetBlockLen()					Name:	  INT8U Sd_SetBlockLen()
** 功能描述: 设置一个块的长度						Function: set a block len of sd card 
** 输　  入: INT32U length	: 块的长度值			Input:	  INT32U length	: the length of a block
** 输 　 出: 0:   正确    >0:   错误码		  		Output:	  0:  right		>0:  error code
*********************************************************************************************************************/
INT8U SD_SetBlockLen(INT32U length)
{
	INT8U param[4],resp,ret;
  
    SD_PackParam(param, length);					/* 将参数转化为字节形式 change the parameter to bytes form */
          												
    ret = SD_SendCmd(CMD16, param, CMD16_R, &resp);
    if (ret != SD_NO_ERR)
 		return ret;									/* 设置块的长度为length失败 set the length of block to length fail */
	
	if (resp != 0)
    	return SD_ERR_CMD_RESP;			   			/* 响应错误 response is error */
    
    return SD_NO_ERR; 								/* 返回执行成功 return perform sucessfully */			
}