SD模块测试程序

XJzy

#include "REG52.H"
////////////////////////****************/
unsigned char *SDInfo1="SD Init Success.";
unsigned char *SDInfo2="SD Init Fail.";
unsigned int xdata ReadBuffer[128]  ;
unsigned int xdata WriteBuffer[128] ;
unsigned int BlockSize;
unsigned long int BlockNR;
//sbit sd_clk=P3^2;
//sbit sd_cse=P3^0;
//sbit sd_dai=P3^3; //Do
//sbit sd_dao=P3^1;  //DI
sbit sd_cse=P1^0;
sbit sd_dao=P1^1;//DI
sbit sd_clk=P1^2;
sbit sd_dai=P1^3;//Do
void Delay5us()
{
unsigned char a=0;
for(a=0;a<40;a++)
;
}
//********************************************
void SD_2Byte_Write(unsigned int IOData)
{
unsigned char BitCounter;
  
for (BitCounter=0;BitCounter<16;BitCounter++)
{
  sd_clk=0;//CLK Low
  
  if(IOData&0x8000)//If the MSB of IOData is 1, then Do=1, else Do=0.
   sd_dao=1;//Do High
  else
   sd_dao=0;//Do Low
   
  sd_clk=1;//CLK High
  Delay5us();
  
  IOData=IOData<<1;//Because the MSB is transmitted firstly, shift to next lower bit.
}
}
//********************************************
void SD_Write(unsigned int IOData)
{
unsigned char BitCounter;
IOData=IOData<<8;

for (BitCounter=0;BitCounter<8;BitCounter++)
{
  sd_clk=0;//CLK Low
  
  if(IOData&0x8000)//If the MSB of IOData is 1, then Do=1, else Do=0.
   sd_dao=1;//Do High
  else
   sd_dao=0;//Do Low
   
  sd_clk=1;//CLK High
  Delay5us();
  
  IOData=IOData<<1;//Because the MSB is transmitted firstly, shift to next lower bit.
}
}
//********************************************
unsigned int SD_2Byte_Read()
{
unsigned int Buffer;
unsigned char BitCounter;
Buffer=0;

for (BitCounter=0;BitCounter<16;BitCounter++)
{
  sd_clk=0;//CLK Low
  Delay5us();
  sd_clk=1;//CLK High
  Buffer=Buffer<<1;//Because the MSB is transmitted firstly, shift to next lower bit.
                   //Because the LSB will be damaged, we can not put this line under next line.
  if(sd_dai)
   Buffer++;//If SPI_Din=1 then the LSB_of_Buffer=1.  
}

return Buffer;
}
//********************************************
unsigned int SD_Read()
{
unsigned int Buffer;
unsigned char BitCounter;
Buffer=0xffff;

for (BitCounter=0;BitCounter<8;BitCounter++)
{
  sd_clk=0;//CLK Low
  Delay5us();
  sd_clk=1;//CLK High
  Buffer=Buffer<<1;//Because the MSB is transmitted firstly, shift to next lower bit.
                   //Because the LSB will be damaged, we can not put this line under next line.
  if(sd_dai)
   Buffer++;//If SPI_Din=1 then the LSB_of_Buffer=1.  
}

return Buffer;
}
//********************************************
unsigned int SD_CMD_Write(unsigned int CMDIndex,unsigned long CMDArg,unsigned int ResType,unsigned int CSLowRSV)//ResType:Response Type, send 1 for R1; send 2 for R1b; send 3 for R2.
{ //There are 7 steps need to do.(marked by [1]-[7])
unsigned int temp,Response,Response2,CRC,MaximumTimes;
Response2=0;
MaximumTimes=10;
CRC=0x0095;//0x0095 is only valid for CMD0
if (CMDIndex!=0) CRC=0x00ff;

sd_cse=0;//[1] CS Low

SD_2Byte_Write(((CMDIndex|0x0040)<<8)+(CMDArg>>24));//[2] Transmit Command_Index & 1st Byte of Command_Argument.
SD_2Byte_Write((CMDArg&0x00ffff00)>>8);    //[2] 2nd & 3rd Byte of Command_Argument
SD_2Byte_Write(((CMDArg&0x000000ff)<<8)+CRC);  //[2] 4th Byte of Command_Argument & CRC only for CMD0

sd_dao=1;//[3] Do High
      //[3] Restore Do to High Level

  for (temp=0;temp<8;temp++)//[4] Provide 8 extra clock after CMD
{
  sd_clk=0;//CLK Low
  Delay5us();
  sd_clk=1;//CLK High
  Delay5us();
}

switch (ResType)//[5] wait response
{
  case 1://R1
    {
     do
      Response=SD_Read();
     while (Response==0xffff);
     break;
    }
  case 2://R1b
    {
     do
      Response=SD_Read();
     while (Response==0xffff);//Read R1 firstly
     
     do
      Response2=SD_Read()-0xff00;
     while (Response2!=0);//Wait until the Busy_Signal_Token is non-zero
     break;
    }
  case 3: Response=SD_2Byte_Read();break;//R2
}

if (CSLowRSV==0) sd_cse=1;//[6] CS High (if the CMD has data block response CS should be kept low)
  
  for (temp=0;temp<8;temp++)//[7] Provide 8 extra clock after card response
{
  sd_clk=0;//CLK Low
  Delay5us();
  sd_clk=1;//CLK High
  Delay5us();
}
return Response;
}
//********************************************
unsigned int SD_Reset_Card()
{
unsigned int temp,MaximumTimes;
MaximumTimes=10;

for (temp=0;temp<80;temp++)//Send 74+ Clocks
{
  sd_clk=0;//CLK Low
  Delay5us();
  sd_clk=1;//CLK High
  Delay5us();
}
  
return SD_CMD_Write(0x0000,0x00000000,1,0);//Send CMD0
}
//********************************************
unsigned int SD_Initiate_Card()//Polling the card after reset
{
unsigned int temp,Response,MaximumTimes;
MaximumTimes=50;

for(temp=0;temp<MaximumTimes;temp++)
{
  Response=SD_CMD_Write(0x0037,0x00000000,1,0);//Send CMD55
  Response=SD_CMD_Write(0x0029,0x00000000,1,0);//Send ACMD41
  if (Response==0xff00)
   temp=MaximumTimes;
}
return Response;
}
//********************************************
unsigned int SD_Get_CardInfo()//Read CSD register
{
unsigned int temp,Response,MaximumTimes;
MaximumTimes=50;

for(temp=0;temp<MaximumTimes;temp++)
{
  Response=SD_CMD_Write(9,0x00000000,1,1);//Send CMD9
  if (Response==0xff00)
   temp=MaximumTimes;
}

  for (temp=0;temp<8;temp++)//Provide 8 clock to romove the first byte of data response (0x00fe)
{
  sd_clk=0;//CLK Low
  Delay5us();
  sd_clk=1;//CLK High
  Delay5us();
}

for (temp=0;temp<8;temp++) ReadBuffer[temp]=SD_2Byte_Read();//Get the CSD data

for (temp=0;temp<16;temp++)//Provide 16 clock to remove the last 2 bytes of data response (CRC)
{
  sd_clk=0;//CLK Low
  Delay5us();
  sd_clk=1;//CLK High
  Delay5us();
}

sd_cse=1;//CS_High()

for (temp=0;temp<8;temp++)//Provide 8 extra clock after data response
{
  sd_clk=0;//CLK Low
  Delay5us();
  sd_clk=1;//CLK High
  Delay5us();
}

BlockNR=((ReadBuffer[3]<<2)&0x0fff)+((ReadBuffer[4]>>14)&0x0003)+1;//Calcuate MULT
BlockNR=BlockNR*(0x0002<<(((ReadBuffer[4]<<1)&0x0007)+((ReadBuffer[5]>>15)&0x0001)+1));//Calcuate Block_Number
return Response;
}
//********************************************
unsigned int SD_Overall_Initiation()
{
unsigned int Response,Response_2;
Response=0x0000;
Response_2=0xff00;

sd_dao=1;//[1] Do High
      //[1] Do must be High when there is no transmition
do
  Response=SD_Reset_Card();//[2] Send CMD0
while (Response!=0xff01);

if (Response!=0xff01) Response_2+=8;

//Response=SD_CMD_Write(8,0x00000000,1,0);//Send CMD8

Response=SD_Initiate_Card();//[3] Send CMD55+ACMD41
if (Response==0xff00)
  ;
else
  {
  Response_2+=4;
  ;
  }

do
  Response=SD_Get_CardInfo();//[4] Read CSD
while (Response!=0xff00);
if (Response==0xff01) Response_2+=2;

return Response_2;
// 0000|0000||0000|0000 Response_2
//                  |||_CSD Fail
//                  ||__CMD55+ACMD41 Fail
//                  |___CMD0 Fail
}
//********************************************
unsigned int SD_Get_CardID()//Read CID register
{
unsigned int temp,Response,MaximumTimes;
MaximumTimes=10;

for(temp=0;temp<MaximumTimes;temp++)
{
  Response=SD_CMD_Write(10,0x00000000,1,1);//Send CMD9
  if (Response==0xff00)
   temp=MaximumTimes;
}

  for (temp=0;temp<8;temp++)//Provide 8 clock to romove the first byte of data response (0x00fe)
{
  sd_clk=0;//CLK Low
  Delay5us();
  sd_clk=1;//CLK High
  Delay5us();
}

for (temp=0;temp<8;temp++) ReadBuffer[temp]=SD_2Byte_Read();//Get the CID data

for (temp=0;temp<16;temp++)//Provide 16 clock to remove the last 2 bytes of data response (CRC)
{
  sd_clk=0;//CLK Low
  Delay5us();
  sd_clk=1;//CLK High
  Delay5us();
}

sd_cse=1;//CS_High()

for (temp=0;temp<8;temp++)//Provide 8 extra clock after data response
{
  sd_clk=0;//CLK Low
  Delay5us();
  sd_clk=1;//CLK High
  Delay5us();
}

return Response;
}
//********************************************
unsigned int Read_Single_Block(unsigned long int BlockAddress)
{
unsigned int temp,Response,MaximumTimes;
MaximumTimes=10;

if (BlockAddress>BlockNR) return 0xff20;//whether BlockAddress out of range?

for(temp=0;temp<MaximumTimes;temp++)
{
  Response=SD_CMD_Write(17,BlockAddress,1,1);//Send CMD17
  if (Response==0xff00)
   temp=MaximumTimes;
}

while (SD_Read()!=0xfffe) {;}
//这里为了使只有512byte的单片机能够读写SD卡，特意节省了RAM的使用量，每次读写只有两个重复的128byte
//如果您使用的单片机拥有1K以上的RAM请将"%128"去掉
for (temp=0;temp<256;temp++) ReadBuffer[temp%128]=SD_2Byte_Read();//Get the readed data

for (temp=0;temp<16;temp++)//Provide 16 clock to remove the last 2 bytes of data response (CRC)
{
  sd_clk=0;//CLK Low
  Delay5us();
  sd_clk=1;//CLK High
  Delay5us();
}

sd_cse=1;//CS_High()

for (temp=0;temp<8;temp++)//Provide 8 extra clock after data response
{
  sd_clk=0;//CLK Low
  Delay5us();
  sd_clk=1;//CLK High
  Delay5us();
}

return Response;
}
//********************************************
unsigned int Write_Single_Block(unsigned long int BlockAddress)
{
unsigned int temp,Response,MaximumTimes;
MaximumTimes=10;

if (BlockAddress>BlockNR) return 0xff20;//whether BlockAddress out of range?

for(temp=0;temp<MaximumTimes;temp++)
{
  Response=SD_CMD_Write(24,BlockAddress,1,1);//Send CMD24
  if (Response==0xff00)
   temp=MaximumTimes;
}

for (temp=0;temp<8;temp++)//Provide 8 extra clock after CMD response
{
  sd_clk=0;//CLK Low
  Delay5us();
  sd_clk=1;//CLK High
  Delay5us();
}

SD_Write(0x00fe);//Send Start Block Token
//这里为了使只有512byte的单片机能够读写SD卡，特意节省了RAM的使用量，每次读写只有两个重复的128byte
//如果您使用的单片机拥有1K以上的RAM请将"%128"去掉
for (temp=0;temp<256;temp++) SD_2Byte_Write(WriteBuffer[temp%128]);//Data Block
SD_2Byte_Write(0xffff);//Send 2 Bytes CRC

Response=SD_Read();
while (SD_Read()!=0xffff) {;}

sd_cse=1;//CS_High()

for (temp=0;temp<8;temp++)//Provide 8 extra clock after data response
{
  sd_clk=0;//CLK Low
  Delay5us();
  sd_clk=1;//CLK High
  Delay5us();
}

return Response;
}
/* 串行通信初始化*/
void UartInit()
{
SCON = 0x50;      // uart 模式1 (8 bit), REN=1；
TMOD = TMOD | 0x20 ;        // 定时器1 模式2；
// TH1  = 0xF7;                // 9600 Bds at 32MHz
// TL1  = 0xF7;

TH1  = 0xFD;                // 9600 Bds at 11.059MHz
  TL1  = 0xFD;
// TH1  = 0xFA;                // 9600 Bds at 22.1184MHz
// TL1  = 0xFA;

ES = 1;       //允许uart中断；
EA = 1;       //允许CPU中断；
TR1 = 1;             //运行定时器1：
}

void send_char_com(unsigned char ch)  
{
    SBUF=ch;
    while(TI==0);
    TI=0;
}
//向串口发送一个字符串
void send_string_com(unsigned char *str,unsigned int len)
{
    unsigned char k=0;

    do
    {
        send_char_com(*(str + k));
        k++;
    } while(k <len);
}
main()
{
unsigned int Data,M_Response;
    unsigned char i;

//初始化要写入的数据
    for(i=0;i<128;i++)
{
      if (i < 64)
   {
     WriteBuffer[i]=0x4141;
   }
   else
   {
    WriteBuffer[i]=0x4242;
   }
}
    UartInit();
  TI = 0;
    M_Response=0x0000;
  M_Response=SD_Overall_Initiation();
M_Response=SD_CMD_Write(16,512,1,0);
   Data=SD_Get_CardID();
  Write_Single_Block(0x0000);
    Read_Single_Block(0x0000);

    for(i=0; i<128; i++)
{   
     send_char_com(ReadBuffer[i]>>8)  ; //向串口发送高8位数据
     send_char_com(ReadBuffer[i] )  ;
}
  
while(1);   
}