mmc.c

调试成功的SD卡源码

/**************************************************************************************
//------------------ MMC/SD-Card Reading and Writing implementation -------------------
//FileName     : mmc.c
//Function     : Connect AVR to MMC/SD 
//Created by   : ZhengYanbo
//Created date : 15/08/2005
//Version      : V1.2
//Last Modified: 19/08/2005
//Filesystem   : Read or Write MMC without any filesystem

//CopyRight (c) 2005 ZhengYanbo
//Email: [e-mail]
****************************************************************************************/
#include <avr/io.h>
#include "mmc.h"

#if USE_MMC
//****************************************************************************
// Port Init
void MMC_Port_Init(void)
//****************************************************************************
{
   //Config ports 
   cbi(MMC_Direction_REG,SPI_DI);          //Set Pin MMC_DI as Input
   sbi(MMC_Direction_REG,SPI_Clock);       //Set Pin MMC_Clock as Output
   sbi(MMC_Direction_REG,SPI_DO);          //Set Pin MMC_DO as Output
   sbi(MMC_Direction_REG,MMC_Chip_Select); //Set Pin MMC_Chip_Select as Output
   //busy led port init
   sbi(MMC_Direction_REG,SPI_BUSY);        //Set spi busy led port output
   sbi(MMC_Write,SPI_BUSY);                      //busy led off
   
   sbi(MMC_Write,MMC_Chip_Select);                        //Set MMC_Chip_Select to High,MMC/SD Invalid.
}

//****************************************************************************
//Routine for Init MMC/SD card(SPI-MODE)
unsigned char MMC_Init(void)
//****************************************************************************
{  
   unsigned char retry,temp;
   unsigned char i;
   unsigned char CMD[] = {0x40,0x00,0x00,0x00,0x00,0x95};
   
   //MMC_Port_Init(); //Init SPI port  

   for(i=0;i<200;i++) //Wait MMC/SD ready...
   {
      asm("nop");
   }
   
   Init_Flag=1; //Set the init flag

   for (i=0;i<0x0f;i++) 
   {
      Write_Byte_MMC(0xff); //send 74 clock at least!!!
   }
	
   //Send Command CMD0 to MMC/SD Card
   retry=0;
   do
   { //retry 200 times to send CMD0 command 
     temp=Write_Command_MMC(CMD);
     retry++;
     if(retry==200) 
     { //time out
       return(INIT_CMD0_ERROR);//CMD0 Error!
     }
   } 
   while(temp!=1);
   
   //Send Command CMD1 to MMC/SD-Card
   CMD[0] = 0x41; //Command 1
   CMD[5] = 0xFF;
   retry=0;
   do
   { //retry 100 times to send CMD1 command 
     temp=Write_Command_MMC(CMD);
     retry++;
     if(retry==100) 
     { //time out
       return(INIT_CMD1_ERROR);//CMD1 Error!
     }
   } 
   while(temp!=0);
   
   Init_Flag=0; //Init is completed,clear the flag 
   
   MMC_Disable();  //set MMC_Chip_Select to high 
   return(0); //All commands have been taken.
} 

//****************************************************************************
//returns the :
// 	size of the card in MB ( ret * 1024^2) == bytes
// 	sector count and multiplier MB are in u08 == C_SIZE / (2^(9-C_SIZE_MULT))
// 	name of the media 
void MMC_get_volume_info(void)
//****************************************************************************
{   
	//unsigned char i;
    VOLUME_INFO_TYPE MMC_volume_Info,*vinf;
    
    vinf=&MMC_volume_Info; //Init the pointoer;
	// read the CSD register
    Read_CSD_MMC(sectorBuffer.data);
	// get the C_SIZE value. bits [73:62] of data
	// [73:72] == sectorBuffer.data[6] && 0x03
	// [71:64] == sectorBuffer.data[7]
	// [63:62] == sectorBuffer.data[8] && 0xc0
	vinf->sector_count = sectorBuffer.data[6] & 0x03;
	vinf->sector_count <<= 8;
	vinf->sector_count += sectorBuffer.data[7];
	vinf->sector_count <<= 2;
	vinf->sector_count += (sectorBuffer.data[8] & 0xc0) >> 6;
		
	// get the val for C_SIZE_MULT. bits [49:47] of sectorBuffer.data
	// [49:48] == sectorBuffer.data[5] && 0x03
	// [47]    == sectorBuffer.data[4] && 0x80
	vinf->sector_multiply = sectorBuffer.data[9] & 0x03;
	vinf->sector_multiply <<= 1;
	vinf->sector_multiply += (sectorBuffer.data[10] & 0x80) >> 7;

	// work out the MBs
	// mega bytes in u08 == C_SIZE / (2^(9-C_SIZE_MULT))
	vinf->size_MB = vinf->sector_count >> (9-vinf->sector_multiply);
	// get the name of the card
	Read_CID_MMC(sectorBuffer.data);
	vinf->name[0] = sectorBuffer.data[3];
	vinf->name[1] = sectorBuffer.data[4];
	vinf->name[2] = sectorBuffer.data[5];
	vinf->name[3] = sectorBuffer.data[6];
	vinf->name[4] = sectorBuffer.data[7];
	vinf->name[5] = 0x00; //end flag
	/*----------------------------------------------------------
    LCDclrscr();
    //Print Product name on lcd
    i=0;
    writestring("Product:");
    while((vinf->name[i]!=0x00)&&(i<16)) writechar(vinf->name[i++]);
    //Print Card Size(eg:128MB)
    gotoxy(1,0);
    writestring("Tot:"); 
    writeNumber(vinf->size_MB); writestring("MB ");
    //gotoxy(2,0);
    //writestring("sector_mult:"); writeNumber(vinf->sector_multiply);
    //gotoxy(3,0);
    //writestring("sect_cnt:"); writeNumber(vinf->sector_count);*/
	
}

//****************************************************************************
//Send a Command to MMC/SD-Card
//Return: the second byte of response register of MMC/SD-Card
unsigned char Write_Command_MMC(unsigned char *CMD)
//****************************************************************************
{
   unsigned char tmp;
   unsigned char retry=0;
   unsigned char i;

   //set MMC_Chip_Select to high (MMC/SD-Card disable) 
   MMC_Disable();
   //send 8 Clock Impulse
   Write_Byte_MMC(0xFF);
   //set MMC_Chip_Select to low (MMC/SD-Card active)
   MMC_Enable();

   //send 6 Byte Command to MMC/SD-Card
   for (i=0;i<0x06;i++) 
   { 
      Write_Byte_MMC(*CMD++);
   }
   
   //get 16 bit response
   Read_Byte_MMC(); //read the first byte,ignore it. 
   do 
   {  //Only last 8 bit is used here.Read it out. 
      tmp = Read_Byte_MMC();
      retry++;
   }
   while((tmp==0xff)&&(retry<100)); 
   return(tmp);
}

//****************************************************************************
//Routine for reading a byte from MMC/SD-Card
unsigned char Read_Byte_MMC(void)
//****************************************************************************
{ 
   unsigned char temp=0;
   unsigned char i;

   cbi(MMC_Write,SPI_BUSY); //MMC_BUSY_LED=0;
   //Software SPI
   for (i=0; i<8; i++) //MSB First
   {
      cbi(MMC_Write,SPI_Clock); //Clock Impuls (Low)
      if(Init_Flag) delay_us_8_;
	  //read mmc data out pin
	  if((MMC_Read&(1<<SPI_DI))!=0)
		  temp = (temp << 1) + 1; 
	  else
		  temp = (temp << 1) + 0;
      sbi(MMC_Write,SPI_Clock); //set Clock Impuls High
      if(Init_Flag) delay_us_8_;	
   }
   sbi(MMC_Write,SPI_BUSY); //MMC_BUSY_LED=1;
   return (temp);
}

//****************************************************************************
//Routine for sending a byte to MMC/SD-Card
void Write_Byte_MMC(unsigned char value)
//****************************************************************************
{ 
   unsigned char i; 
   
   cbi(MMC_Write,SPI_BUSY); //MMC_BUSY_LED=0; 
   //Software SPI
   for (i=0; i<8; i++) 
   {  //write a byte
      if (((value >> (7-i)) & 0x01)==0x01)
		  sbi(MMC_Write,SPI_DO); //Send bit by bit(MSB First)
      else
		  cbi(MMC_Write,SPI_DO);
      cbi(MMC_Write,SPI_Clock); //set Clock Impuls low
      if(Init_Flag) delay_us_8_; 
      sbi(MMC_Write,SPI_Clock); //set Clock Impuls High
      if(Init_Flag) delay_us_8_;     
   }//write a byte
   sbi(MMC_Write,SPI_DO);	//set Output High 
   sbi(MMC_Write,SPI_BUSY); //MMC_BUSY_LED=1;
}

//****************************************************************************
//Routine for writing a Block(512Byte) to MMC/SD-Card
//Return 0 if sector writing is completed.
unsigned char MMC_write_sector(unsigned long addr,unsigned char *Buffer)
//****************************************************************************
{  
   unsigned char tmp,retry;
   unsigned int i;