sd_card.h

SD卡的SD模式的读写驱动

#include "system.h"
#include "altera_avalon_pio_regs.h"
#ifndef   __SD_Card_H__
#define   __SD_Card_H__
//-------------------------------------------------------------------------
//  SD Card Set I/O Direction
#define SD_CMD_IN   IOWR(SD_CMD_BASE, 1, 0)
#define SD_CMD_OUT  IOWR(SD_CMD_BASE, 1, 1)
#define SD_DAT_IN   IOWR(SD_DAT_BASE, 1, 0x0)
#define SD_DAT_OUT  IOWR(SD_DAT_BASE, 1, 0x0f)
//  SD Card Output High/Low
#define SD_CMD_LOW  IOWR(SD_CMD_BASE, 0, 0)
#define SD_CMD_HIGH IOWR(SD_CMD_BASE, 0, 1)
#define SD_DAT_LOW  IOWR(SD_DAT_BASE, 0, 0x0)
#define SD_DAT_HIGH IOWR(SD_DAT_BASE, 0, 0x0f)
#define SD_CLK_LOW  IOWR(SD_CLK_BASE, 0, 0)
#define SD_CLK_HIGH IOWR(SD_CLK_BASE, 0, 1)
//  SD Card Input Read
#define SD_TEST_CMD IORD(SD_CMD_BASE, 0)
#define SD_TEST_DAT IORD(SD_DAT_BASE, 0)


#define SDDAT0  (1<<0)
#define SDDAT1  (1<<1)
#define SDDAT2  (1<<2)
#define SDDAT3  (1<<3)
#define PIOSET(PIN) IOWR_ALTERA_AVALON_PIO_DATA(\
                 (SD_DAT_BASE),(PIN))//方便修改位置端口
//-------------------------------------------------------------------------
#define BYTE    unsigned char
#define UINT16  unsigned int
#define UINT32  unsigned long
//-------------------------------------------------------------------------
void Ncr(void);
void Ncc(void);
BYTE response_R(BYTE);
BYTE send_cmd(BYTE *);
BYTE SD_read_lba(BYTE *,UINT32,UINT32);
BYTE SD_card_init(void);
UINT16 GetCRC16(BYTE *, UINT16);
BYTE exam_crc(void);
//unsigned int BlockCRC16Table(unsigned char *,int);
BYTE  statshift(void);
BYTE  disconnect(void);
//-------------------------------------------------------------------------
BYTE read_status;
BYTE response_buffer[20];
BYTE RCA[2];
BYTE cmd_buffer[5];
const BYTE cmd0[5]   = {0x40,0x00,0x00,0x00,0x00};
const BYTE cmd55[5]  = {0x77,0x00,0x00,0x00,0x00};
const BYTE cmd2[5]   = {0x42,0x00,0x00,0x00,0x00};
const BYTE cmd3[5]   = {0x43,0x00,0x00,0x00,0x00};
const BYTE cmd7[5]   = {0x47,0x00,0x00,0x00,0x00};
const BYTE cmd9[5]   = {0x49,0x00,0x00,0x00,0x00};
const BYTE cmd16[5]  = {0x50,0x00,0x00,0x02,0x00};
const BYTE cmd17[5]  = {0x51,0x00,0x00,0x00,0x00};
const BYTE cmd24[5]  = {0x58,0x00,0x00,0x00,0x00}; //写命令
const BYTE acmd6[5]  = {0x46,0x00,0x00,0x00,0x02};
const BYTE cmd32[5]  = {0x60,0x00,0x00,0x00,0x00};//erase block start
const BYTE cmd33[5]  = {0x61,0x00,0x00,0x00,0x00};//erase block end
const BYTE cmd38[5]  = {0x66,0x00,0x00,0x00,0x00};
const BYTE acmd41[5] = {0x69,0x0f,0xf0,0x00,0x00};
const BYTE acmd42[5] = {0x6a,0x00,0x00,0x00,0x00};
const BYTE acmd51[5] = {0x73,0x00,0x00,0x00,0x00};
/////////////////////////////////////////////////////
void N_busy(void)
{
  int i;
  SD_CMD_IN;
  for(i=0;i<6;i++)
  {
    SD_CLK_LOW;
    SD_CLK_HIGH;
  }
 
} 
////////////////////////////////////////////////////////
//-------------------------------------------------------------------------
void Ncr(void)
{
  SD_CMD_IN;
  SD_CLK_LOW;
  SD_CLK_HIGH;
  SD_CLK_LOW;
  SD_CLK_HIGH;
} 
//-------------------------------------------------------------------------
void Ncc(void)
{
  int i;
  for(i=0;i<8;i++)
  {
    SD_CLK_LOW;
    SD_CLK_HIGH;
  }
}
//-------------------------------------------------------------------------
BYTE SD_card_init(void)
{
    BYTE x,y;
    SD_DAT_OUT;
    //PIOSET(SDDAT3);
    IOWR(SD_DAT_BASE, 1, 0x8); //设置SD_DAT[3]
    IOWR(SD_DAT_BASE, 0, 0x8);
    
    SD_CMD_OUT;
    SD_DAT_IN;
    SD_CLK_HIGH;
    SD_CMD_HIGH;
    SD_DAT_LOW;
    read_status=0;
    for(x=0;x<40;x++)
    Ncr();
    for(x=0;x<5;x++)
    cmd_buffer[x]=cmd0[x];
    y = send_cmd(cmd_buffer);
    do
    {
      for(x=0;x<40;x++);
      Ncc();
      for(x=0;x<5;x++)
      cmd_buffer[x]=cmd55[x];
      y = send_cmd(cmd_buffer);
      Ncr();
      if(response_R(1)>1) //response too long or crc error
      return 1;
      Ncc();
      for(x=0;x<5;x++)
      cmd_buffer[x]=acmd41[x];
      y = send_cmd(cmd_buffer);
      Ncr();      
    } while(response_R(3)==1);
    Ncc();
    for(x=0;x<5;x++)
    cmd_buffer[x]=cmd2[x];
    y = send_cmd(cmd_buffer);
    Ncr();
    if(response_R(2)>1)
    return 1;
    Ncc();
    for(x=0;x<5;x++)
    cmd_buffer[x]=cmd3[x];
    y = send_cmd(cmd_buffer);
    Ncr();
    if(response_R(6)>1)
    return 1;         
    RCA[0]=response_buffer[1];
    RCA[1]=response_buffer[2];
    Ncc();
    for(x=0;x<5;x++)
    cmd_buffer[x]=cmd9[x];
    cmd_buffer[1] = RCA[0];
    cmd_buffer[2] = RCA[1];  
    y = send_cmd(cmd_buffer);
    Ncr();
    if(response_R(2)>1)
    return 1; 
    Ncc();
    for(x=0;x<5;x++)
    cmd_buffer[x]=cmd7[x];
    cmd_buffer[1] = RCA[0];
    cmd_buffer[2] = RCA[1];
    y = send_cmd(cmd_buffer);
    Ncr();
    if(response_R(1)>1)
    return 1; 
    Ncc();
    for(x=0;x<5;x++)
    cmd_buffer[x]=cmd16[x];
    y = send_cmd(cmd_buffer);  
    Ncr();
    if(response_R(1)>1)
    return 1;
    ///////////////////////////////////
    for(x=0;x<40;x++);   // 1 to 4 line  
    Ncc();     
    for(x=0;x<5;x++)
    cmd_buffer[x]=cmd55[x];
    cmd_buffer[1] = RCA[0];
    cmd_buffer[2] = RCA[1];
    y = send_cmd(cmd_buffer);
    Ncr();    
    if(response_R(1)>1)
    return 1;
      
    Ncc();
    for(x=0;x<5;x++)
    cmd_buffer[x]=acmd6[x];
    y = send_cmd(cmd_buffer);   
    Ncr();      
    if(response_R(1)>1)
      return 1;
    
    //////////////////////////////////
  //sd card ready
   for(x=0;x<40;x++);   //  
    Ncc();     
    for(x=0;x<5;x++)
    cmd_buffer[x]=cmd55[x];
    cmd_buffer[1] = RCA[0];
    cmd_buffer[2] = RCA[1];
    y = send_cmd(cmd_buffer);
    Ncr();    
    if(response_R(1)>1)
    return 1;
      
    Ncc();
    for(x=0;x<5;x++)
    cmd_buffer[x]=acmd42[x];
    y = send_cmd(cmd_buffer);   
    Ncr();      
    if(response_R(1)>1)   
      return 1; 
    read_status =1;
    return 0;
}
//-------------------------------------------------------------------------
   
BYTE  statshift(void)
 {   BYTE x,y;
     Ncc();
    for(x=0;x<5;x++)
    cmd_buffer[x]=cmd7[x];
    cmd_buffer[1] = RCA[0];
    cmd_buffer[2] = RCA[1];
    y = send_cmd(cmd_buffer);
    Ncr();
    if(response_R(1)>1)
    return 1; 
    
    Ncc();
    for(x=0;x<5;x++)
    cmd_buffer[x]=cmd7[x];
    cmd_buffer[1] = RCA[0];
    cmd_buffer[2] = RCA[1];
    y = send_cmd(cmd_buffer);
    Ncr();
    if(response_R(1)>1)
    return 1; 
 }
BYTE  disconnect(void)
{
    BYTE x,y;
    Ncc();
    for(x=0;x<5;x++)
    cmd_buffer[x]=cmd7[x];
    cmd_buffer[1] = RCA[0];
    cmd_buffer[2] = RCA[1];
    y = send_cmd(cmd_buffer);
    Ncr();
    if(response_R(1)>1)
    return 1; 
}
    ////////////////////////
//-------------------------------------------------------------
BYTE SD_EraseBlock(UINT32 startaddr, UINT32 num)
{   
    BYTE i;
    startaddr+=97;
    Ncc();
    for(i=0;i<5;i++)
    cmd_buffer[0]=  cmd32[0];
    cmd_buffer[1] = (startaddr>>15)&0xff; 
    cmd_buffer[2] = (startaddr>>7)&0xff;
    cmd_buffer[3] = (startaddr<<1)&0xff;
    cmd_buffer[4] = 0;
    send_cmd(cmd_buffer);  
    Ncr();
    if(response_R(1)>1)
    return 1;
    Ncc();
    for(i=0;i<5;i++)
    cmd_buffer[0]=  cmd33[0];
    cmd_buffer[1] = ((startaddr+num-1)>>15)&0xff; 
    cmd_buffer[2] = ((startaddr+num-1)>>7)&0xff;
    cmd_buffer[3] = ((startaddr+num-1)<<1)&0xff;
    cmd_buffer[4] = 0;
    send_cmd(cmd_buffer);  
    Ncr();
    if(response_R(1)>1)
    return 1;
    Ncc();
    for(i=0;i<5;i++)
    cmd_buffer[i]=cmd38[i];
    send_cmd(cmd_buffer);  
    Ncr();
    if(response_R(1)>1)
    return 1;
    while(1)
    {
      SD_CLK_LOW;
      SD_CLK_HIGH;      
      if((IORD(SD_DAT_BASE, 0)&0x0f)!=0)////////////////////////////////////////
      break;
    }     
 }

//-------------------------------------------------------------------------
BYTE SD_read_lba(BYTE *buff,UINT32 lba,UINT32 seccnt)
{
  BYTE c=0, x,y;
  UINT32  i,j;
  lba+=97;
    //SD_CMD_OUT;  
  SD_DAT_IN;
 
  for(j=0;j<seccnt;j++)
  {
    {
      Ncc();
      cmd_buffer[0] = cmd17[0];
      cmd_buffer[1] = (lba>>15)&0xff;
      cmd_buffer[2] = (lba>>7)&0xff;
      cmd_buffer[3] = (lba<<1)&0xff;
      cmd_buffer[4] = 0;
      lba++;
      send_cmd(cmd_buffer); 
      Ncr();
      //if(response_R(1)>1)
     // return 1; 
    } 
    while(1)
    {
      SD_CLK_LOW;
      SD_CLK_HIGH;
      if((IORD(SD_DAT_BASE, 0)&0x0f)==0)//检测到起始位值为0
      break;
    }
    for(i=0;i<512;i++)
    {
      BYTE j;
      c=0;
      for(j=0;j<2;j++)
      {
        SD_CLK_LOW;
        SD_CLK_HIGH;
        c <<= 4; 
        c |= (IORD(SD_DAT_BASE, 0)&0x0f);
//if(SD_TEST_DAT)
       // c |= 0x0f;
       //SD_CLK_LOW;
       //SD_CLK_HIGH;
      } 
      *buff=c;
      buff++;
    } 
    for(i=0; i<16; i++)//16位CRC检验值不接收
    {
        SD_CLK_LOW;
        SD_CLK_HIGH;
    }
  }
  read_status = 1;  //SD data next in
  return 0;
}
//-------------------------------------------------------------------------
BYTE response_R(BYTE s)
{
  BYTE a=0,b=0,c=0,r=0,crc=0;
  BYTE i,j=6,k;
  while(1)
  {
    SD_CLK_LOW;
    SD_CLK_HIGH;
    if(!(SD_TEST_CMD))
    break;
    if(crc++ >100)
    return 2;
  } 
  crc =0;
  if(s == 2)
  j = 17;

  for(k=0; k<j; k++)
  {
    c = 0;
    if(k > 0)                      //for crc culcar
    b = response_buffer[k-1];    
    for(i=0; i<8; i++)
    {
      SD_CLK_LOW;
      if(a > 0)
      c <<= 1; 
      else
      i++; 
      a++; 
      SD_CLK_HIGH;
      if(SD_TEST_CMD)
      c |= 0x01;
      if(k > 0)
      {
        crc <<= 1;
        if((crc ^ b) & 0x80)
        crc ^= 0x09;
        b <<= 1;
        crc &= 0x7f;
      }
    }
    if(s==3)
    { 
      if( k==1 &&(!(c&0x80)))
      r=1;
    }
    response_buffer[k] = c;