STM库里面的 SDIO驱动SD卡POWER ON 代码好怪异，在CMD8后为什么要发好几个CMD55才发CMD41？下图中红 {MOD}的2个CMD55干什么用的？
还有ACMD41命令为什么要重复发送直到validvoltage==1（这个好像是检测多卡）？？
CMD8--------------------------------------------------->CMD55
| OK err |
SDType=SD_HIGH_CAPACITY |
| <------------------------------------------------------------
CMD55
|<----------------
CMD55 |
| |
CMD41 |
|------------------
|
/* CMD8: SEND_IF_COND --------------------------------------------------------*/
/* Send CMD8 to verify SD card interface operating condition */
/* Argument: - [31:12]: Reserved (shall be set to '0')
- [11:8]: Supply Voltage (VHS) 0x1 (Range: 2.7-3.6 V)
- [7:0]: Check Pattern (recommended 0xAA) */
/* CMD Response: R7 */
SDIO_CmdInitStructure.SDIO_Argument = SD_CHECK_PATTERN;
SDIO_CmdInitStructure.SDIO_CmdIndex = SDIO_SEND_IF_COND;
SDIO_CmdInitStructure.SDIO_Response = SDIO_Response_Short;
SDIO_CmdInitStructure.SDIO_Wait = SDIO_Wait_No;
SDIO_CmdInitStructure.SDIO_CPSM = SDIO_CPSM_Enable;
SDIO_SendCommand(&SDIO_CmdInitStructure);
errorstatus = CmdResp7Error();
if (errorstatus == SD_OK)
{
CardType = SDIO_STD_CAPACITY_SD_CARD_V2_0; /* SD Card 2.0 */
SDType = SD_HIGH_CAPACITY;
}
else
{
/* CMD55 */
SDIO_CmdInitStructure.SDIO_Argument = 0x00;
SDIO_CmdInitStructure.SDIO_CmdIndex = SDIO_APP_CMD;
SDIO_CmdInitStructure.SDIO_Response = SDIO_Response_Short;
SDIO_CmdInitStructure.SDIO_Wait = SDIO_Wait_No;
SDIO_CmdInitStructure.SDIO_CPSM = SDIO_CPSM_Enable;
SDIO_SendCommand(&SDIO_CmdInitStructure);
errorstatus = CmdResp1Error(SDIO_APP_CMD);
}
/* CMD55 */
SDIO_CmdInitStructure.SDIO_Argument = 0x00;
SDIO_CmdInitStructure.SDIO_CmdIndex = SDIO_APP_CMD;
SDIO_CmdInitStructure.SDIO_Response = SDIO_Response_Short;
SDIO_CmdInitStructure.SDIO_Wait = SDIO_Wait_No;
SDIO_CmdInitStructure.SDIO_CPSM = SDIO_CPSM_Enable;
SDIO_SendCommand(&SDIO_CmdInitStructure);
errorstatus = CmdResp1Error(SDIO_APP_CMD);
/* If errorstatus is Command TimeOut, it is a MMC card */
/* If errorstatus is SD_OK it is a SD card: SD card 2.0 (voltage range mismatch)
or SD card 1.x */
if (errorstatus == SD_OK)
{
/* SD CARD */
/* Send ACMD41 SD_APP_OP_COND with Argument 0x80100000 */
while ((!validvoltage) && (count < SD_MAX_VOLT_TRIAL))
{
/* SEND CMD55 APP_CMD with RCA as 0 */
SDIO_CmdInitStructure.SDIO_Argument = 0x00;
SDIO_CmdInitStructure.SDIO_CmdIndex = SDIO_APP_CMD;
SDIO_CmdInitStructure.SDIO_Response = SDIO_Response_Short;
SDIO_CmdInitStructure.SDIO_Wait = SDIO_Wait_No;
SDIO_CmdInitStructure.SDIO_CPSM = SDIO_CPSM_Enable;
SDIO_SendCommand(&SDIO_CmdInitStructure);
errorstatus = CmdResp1Error(SDIO_APP_CMD);
if (errorstatus != SD_OK)
{
return(errorstatus);
}
SDIO_CmdInitStructure.SDIO_Argument = SD_VOLTAGE_WINDOW_SD | SDType;
SDIO_CmdInitStructure.SDIO_CmdIndex = SDIO_SD_APP_OP_COND;
SDIO_CmdInitStructure.SDIO_Response = SDIO_Response_Short;
SDIO_CmdInitStructure.SDIO_Wait = SDIO_Wait_No;
SDIO_CmdInitStructure.SDIO_CPSM = SDIO_CPSM_Enable;
SDIO_SendCommand(&SDIO_CmdInitStructure);
errorstatus = CmdResp3Error();
if (errorstatus != SD_OK)
{
return(errorstatus);
}
response = SDIO_GetResponse(SDIO_RESP1);
validvoltage = (bool) (((response >> 31) == 1) ? 1 : 0);
count++;
}
if (count >= SD_MAX_VOLT_TRIAL)
{
errorstatus = SD_INVALID_VOLTRANGE;
return(errorstatus);
}
if (response &= SD_HIGH_CAPACITY)
{
CardType = SDIO_HIGH_CAPACITY_SD_CARD;
}
}/* else MMC Card */
友情提示: 此问题已得到解决，问题已经关闭,关闭后问题禁止继续编辑，回答。
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if(errorstatus==SD_OK)break;
}
if(errorstatus)return errorstatus;//返回错误状态
SDIO_Send_Cmd(SDIO_SEND_IF_COND,1,SD_CHECK_PATTERN);//发送CMD8,短响应,检查SD卡接口特性.
//arg[11:8]:01,支持电压范围,2.7~3.6V
//arg[7:0]:默认0XAA
//返回响应7
errorstatus=CmdResp7Error(); //等待R7响应
if(errorstatus==SD_OK) //R7响应正常
{
CardType=SDIO_STD_CAPACITY_SD_CARD_V2_0; //SD 2.0卡
SDType=SD_HIGH_CAPACITY; //高容量卡
}
SDIO_Send_Cmd(SD_CMD_APP_CMD,1,0); //发送CMD55,短响应
errorstatus=CmdResp1Error(SD_CMD_APP_CMD); //等待R1响应
if(errorstatus==SD_OK)//SD2.0/SD 1.1,否则为MMC卡
{
//SD卡,发送ACMD41 SD_APP_OP_COND,参数为:0x80100000
while((!validvoltage)&&(count<SD_MAX_VOLT_TRIAL))
{
SDIO_Send_Cmd(SD_CMD_APP_CMD,1,0); //发送CMD55,短响应
errorstatus=CmdResp1Error(SD_CMD_APP_CMD); //等待R1响应
if(errorstatus!=SD_OK)return errorstatus; //响应错误
SDIO_Send_Cmd(SD_CMD_SD_APP_OP_COND,1,SD_VOLTAGE_WINDOW_SD|SDType);//发送ACMD41,短响应
errorstatus=CmdResp3Error(); //等待R3响应
if(errorstatus!=SD_OK)return errorstatus; //响应错误
response=SDIO->RESP1;; //得到响应
validvoltage=(((response>>31)==1)?1:0); //判断SD卡上电是否完成
count++;
}
原子哥，你这个代码里，不是在发送ACMP41其间，也有一次是发送了2个CMD55吗？
我的SDIO例程就没有用到2次CMD55.
SD_Error SD_PowerON(void)
{
u8 i=0;
SD_Error errorstatus=SD_OK;
u32 response=0,count=0,validvoltage=0;
u32 SDType=SD_STD_CAPACITY;
//配置CLKCR寄存器
SDIO->CLKCR=0; //清空CLKCR之前的设置
SDIO->CLKCR|=0<<9; //非省电模式
SDIO->CLKCR|=0<<10; //关闭旁路,CK根据分频设置输出
SDIO->CLKCR|=0<<11; //1位数据宽度
SDIO->CLKCR|=0<<13; //SDIOCLK上升沿产生SDIOCK
SDIO->CLKCR|=0<<14; //关闭硬件流控制
SDIO_Clock_Set(SDIO_INIT_CLK_DIV);//设置时钟频率(初始化的时候,不能超过400Khz)
SDIO->
SDIO->CLKCR|=1<<8; //SDIOCK使能
for(i=0;i<74;i++)
{
SDIO_Send_Cmd(SD_CMD_GO_IDLE_STATE,0,0);//发送CMD0进入IDLE STAGE模式命令.
errorstatus=CmdError();
if(errorstatus==SD_OK)break;
}
if(errorstatus)return errorstatus;//返回错误状态
SDIO_Send_Cmd(SDIO_SEND_IF_COND,1,SD_CHECK_PATTERN);//发送CMD8,短响应,检查SD卡接口特性.
//arg[11:8]:01,支持电压范围,2.7~3.6V
//arg[7:0]:默认0XAA
//返回响应7
errorstatus=CmdResp7Error(); //等待R7响应
if(errorstatus==SD_OK) //R7响应正常
{
CardType=SDIO_STD_CAPACITY_SD_CARD_V2_0; //SD 2.0卡
SDType=SD_HIGH_CAPACITY; //高容量卡
}
SDIO_Send_Cmd(SD_CMD_APP_CMD,1,0); //发送CMD55,短响应
errorstatus=CmdResp1Error(SD_CMD_APP_CMD); //等待R1响应
if(errorstatus==SD_OK)//SD2.0/SD 1.1,否则为MMC卡
{
//SD卡,发送ACMD41 SD_APP_OP_COND,参数为:0x80100000
while((!validvoltage)&&(count<SD_MAX_VOLT_TRIAL))
{
SDIO_Send_Cmd(SD_CMD_APP_CMD,1,0); //发送CMD55,短响应
errorstatus=CmdResp1Error(SD_CMD_APP_CMD); //等待R1响应
if(errorstatus!=SD_OK)return errorstatus; //响应错误
SDIO_Send_Cmd(SD_CMD_SD_APP_OP_COND,1,SD_VOLTAGE_WINDOW_SD|SDType);//发送ACMD41,短响应
errorstatus=CmdResp3Error(); //等待R3响应
if(errorstatus!=SD_OK)return errorstatus; //响应错误
response=SDIO->RESP1;; //得到响应
validvoltage=(((response>>31)==1)?1:0); //判断SD卡上电是否完成
count++;
}
if(count>=SD_MAX_VOLT_TRIAL)
{
errorstatus=SD_INVALID_VOLTRANGE;
return errorstatus;
}
if(response&=SD_HIGH_CAPACITY)
{
CardType=SDIO_HIGH_CAPACITY_SD_CARD;
}
}else//MMC卡
{
//MMC卡,发送CMD1 SDIO_SEND_OP_COND,参数为:0x80FF8000
while((!validvoltage)&&(count<SD_MAX_VOLT_TRIAL))
{
SDIO_Send_Cmd(SD_CMD_SEND_OP_COND,1,SD_VOLTAGE_WINDOW_MMC);//发送CMD1,短响应
errorstatus=CmdResp3Error(); //等待R3响应
if(errorstatus!=SD_OK)return errorstatus; //响应错误
response=SDIO->RESP1;; //得到响应
validvoltage=(((response>>31)==1)?1:0);
count++;
}
if(count>=SD_MAX_VOLT_TRIAL)
{
errorstatus=SD_INVALID_VOLTRANGE;
return errorstatus;
}
CardType=SDIO_MULTIMEDIA_CARD;
}
return(errorstatus);
}
---------------------------------
哦，暂时还没遇到问题...
谢谢你的建议。
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