430和sd卡通信 spi模式

只看该作者 · 2015-8-5 17:51

SD的初始化过程中，在送出CMD55后,回复的是0x01对的。但在送出ACMD41后,回复的确不是0x00.请帮我看看我的程序有什么问题吧，谢谢！
初始化程序如下：
//================================================================================================
//实现功能：初始化SD卡（参考SD卡初始化时序）
//================================================================================================
unsigned char SdInit(void)
{
unsigned char i,time=0;
unsigned char response=0x00;

      //send CMD0,如果response=0x01则SD卡成功转到SPI模式
      do
      {
      P1OUT |=0x80;          //SD_CS=1;
   for(i=0;i<=9;i++)    //复位时最少写入74个时钟周期
      SdWrite(0xff);
   P1OUT &=0x7f;          //SD_CS=0;       复位后CS拉低

      SdCommand(0x00,0,0x95); //Send Command 0 to put MMC in SPI mode
      response=SdResponse();

      time++;
      }
      while((response!=0x01)&&(time<100)); //等待命令CMD0的响应
      if(time==100)return 0; //100次仍然不能得到命令CMD0的响应,超时退出


      //SD卡在进入SPI模式后，激活命令为Cmd55,ACmd41
   do {
         SdCommand(0x37,0,0xff);
         response=SdResponse();
         if (response!=0x01)
         {
            lcd_pos(4,0);
            Disp_HZ("55失败",3);
            return 0;
         }
         SdCommand(0x29,0,0xff);
         response=SdResponse();
            } while (response!=0x00);
      //最后CS拉高
P1OUT |=0x80;          //SD_CS=1;
SdWrite(0xff);          //补偿8个时钟
return 1;             //初始化成功，返回成功信号1
}

只看该作者 · 2016-8-11 13:24

给你一个调试成功的代码
Uint8 SD_Init(void)
{
Uint8 time=0;
temp = 0;
Uint8 Rev_Data[4]={0};
Uint8 pcmd8[] = {0x48,0x00,0x00,0x01,0xAA,0x87};  //CMD8
Uint8 pcmd55[] = {0x77,0x00,0x00,0x00,0x00,0x00};  //CMD55
Uint8 pcmd41[] = {0x69,0x40,0x00,0x00,0x00,0x00};  //CMD41
Uint8 pcmd58[] = {0x7A,0x00,0x00,0x00,0x00,0x00};  //CMD58


P9OUT &= ~BIT0; //打开片选
   temp = SD_WriteCmd(pcmd8);  //读取卡片版本
   if(temp==0x05)
   {
   SD_Type =SDV1;
      //设置卡类型为SD V1.0，如果是V1.0卡，CM8指令后没有后续数据
   P9OUT |= BIT0;
   SD_ReadWriteByte(0xff); //多发8时钟
   P9OUT &= ~BIT0;
   do
   {
   temp = SD_WriteCmd(pcmd55);
   if(temp!=0x01) return temp;
   temp = SD_WriteCmd(pcmd41);
   time++;
   }while((temp!= 0x00)&& (time<200));
   P9OUT |= BIT0;
   }// if(temp==0x05)
   else if(temp == 0x01)
   {
      //V2.0卡，CM8命令后会传回4字节的数据，要跳过再结束本命令
      Rev_Data[0] = SD_ReadWriteByte(0xff);  //返回0x00
      Rev_Data[1] = SD_ReadWriteByte(0xff);  //返回0x00
      Rev_Data[2] = SD_ReadWriteByte(0xff);  //返回0x01
      Rev_Data[3] = SD_ReadWriteByte(0xff);  //返回0xAA

      P9OUT |= BIT0;
      SD_ReadWriteByte(0xff); //多发8时钟
      P9OUT &= ~BIT0;
      do
      {
      temp = SD_WriteCmd(pcmd55);
      if(temp!=0x01) return temp;
      temp = SD_WriteCmd(pcmd41);
      time++;
      if(time>250) return temp;
      }while(temp!= 0x00);

//初始化指令发送完成，接下来获取OCR信息
/*------鉴别SD2.0卡版本--------------*/

      temp=SD_WriteCmd(pcmd58);
      if(temp != 0x00)return temp;
   //读OCR指令发出后，紧接着是4字节的OCR信息
      Rev_Data[0] = SD_ReadWriteByte(0xff);
      Rev_Data[1] = SD_ReadWriteByte(0xff);
      Rev_Data[2] = SD_ReadWriteByte(0xff);
      Rev_Data[3] = SD_ReadWriteByte(0xff);
      P9OUT |= BIT0;
      SD_ReadWriteByte(0xff);
      if(Rev_Data[0] & 0x40) SD_Type = SDHC;
         else SD_Type =SDV2;
   }// else if(temp == 0x01)

   UCB2BR0 = 0x01;  //SD为高速
   UCB2BR1 = 0x00;
return 1;

430和sd卡通信 spi模式

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