最近在用STM32F103Vet6+STemwin做一个拼音输入法的项目,所以字库必须放到TF卡上,所以必使用到SD卡驱动,因为同时要使用USB访问SD卡,所以SD卡必须保证在最佳性能状态,在网上找了几种驱动测试,都出现卡死现像,包括原子哥的驱动同出现问题.还试了中断模式和查询模式,只有查询模式效果最好,但是要把SD卡的工作频率降到10M以下才能工作正常.就将就用查询模式吧,就在昨晚又开始死机了,没办法了,但是总不能放弃项目吧,只好分析代码了,再静下来想一想,SD的工作频率24M,CPU的频率才72M,在4位模式下那CPU起不是要在10个周期(72242+开销)内处理完SD卡的传送?立该用printf在SD_Read上把结果打印出来,结果返回RXOVRRUN,明显了,就是CPU取数速度跟不上SDIO。好,问题找到了,就开始修改
DRESULT disk_read (
BYTE drv, /* Physical drive nmuber (0..) */
BYTE *buff, /* Data buffer to store read data */
DWORD sector, /* Sector address (LBA) */
BYTE count /* Number of sectors to read (1..255) */
)
{
BYTE i;
SD_Error Status;
if (!count) return RES_PARERR; //count????????0??·??ò·????????í?ó
if(drv==0)
{
//int i;
//Status = SD_ReadDisk(buff,sector,count);
/*for(i=0;i<512;i++)
{
Debug("0x%02x ",*(buff+i));
}
Debug("
");*/
/*switch(SD_Mode)
{
case 0: //dma·???
if(count==1)// 1??sector??????×÷
{ */
for(i = 0; i < count; i++)
{
Status = SD_ReadBlock((sector + i) << 9,(u32 *)(&buff[i<<9]),BlockSize);
//Debug("Read:%d
",Status);
}
/* }
else
{
Status = SD_ReadMultiBlocks(sector << 9,(u32 *)(&buff[0]),BlockSize,count);
}
break;
case 1:
DISABLE_INT();
if(count==1)
{
Status = SD_ReadBlock(sector<<9,(u32 *)(&buff[0]),BlockSize);
}
else
{
Status = SD_ReadMultiBlocks(sector<<9 ,(u32 *)(&buff[0]),BlockSize,count);
}
ENABLE_INT();*/
/* break;
default:
Status=SD_ERROR;
}*/
if(Status == SD_OK)
return RES_OK;
else
return RES_ERROR;
}
else//???§??????0????×÷
{
return RES_ERROR;
}
}
从上面代码可以看到我把MutilReadBlock屏蔽了,为什么要屏蔽呢?我们来分析一吓,因为DMA SIZE只有512字节,如果我们用MutilReadBlock来读SD卡的话,由于CPU速度问题,CPU没有把512字节取完,SDIO就会继续向DMA里传数据,这里如果DMA满了,就会产生RXOVRRUN。改了以上代码测试,结果返回OK了,但是STemwin的界面还是没有正确,在这里估计是掉数据了,于是再分析ReadBlock方法
SD_Error SD_ReadBlock(uint32_t addr, uint32_t *readbuff, uint16_t BlockSize)
{
SD_Error errorstatus = SD_OK;
uint32_t count = 0, *tempbuff = readbuff;
uint8_t power = 0;
if (NULL == readbuff)
{
errorstatus = SD_INVALID_PARAMETER;
return(errorstatus);
}
TransferError = SD_OK;
TransferEnd = 0;
TotalNumberOfBytes = 0;
/* Clear all DPSM configuration */
SDIO_DataInitStructure.SDIO_DataTimeOut = SD_DATATIMEOUT;
SDIO_DataInitStructure.SDIO_DataLength = 0;
SDIO_DataInitStructure.SDIO_DataBlockSize = SDIO_DataBlockSize_1b;
SDIO_DataInitStructure.SDIO_TransferDir = SDIO_TransferDir_ToCard;
SDIO_DataInitStructure.SDIO_TransferMode = SDIO_TransferMode_Block;
SDIO_DataInitStructure.SDIO_DPSM = SDIO_DPSM_Disable;
SDIO_DataConfig(&SDIO_DataInitStructure);
SDIO_DMACmd(DISABLE);
if (SDIO_GetResponse(SDIO_RESP1) & SD_CARD_LOCKED)
{
errorstatus = SD_LOCK_UNLOCK_FAILED;
return(errorstatus);
}
if (CardType == SDIO_HIGH_CAPACITY_SD_CARD)
{
BlockSize = 512;
addr /= 512;
}
if ((BlockSize > 0) && (BlockSize <= 2048) && ((BlockSize & (BlockSize - 1)) == 0))
{
power = convert_from_bytes_to_power_of_two(BlockSize);
/* Set Block Size for Card */
SDIO_CmdInitStructure.SDIO_Argument = (uint32_t) BlockSize;
SDIO_CmdInitStructure.SDIO_CmdIndex = SDIO_SET_BLOCKLEN;
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_SET_BLOCKLEN);
if (SD_OK != errorstatus)
{
return(errorstatus);
}
}
else
{
errorstatus = SD_INVALID_PARAMETER;
return(errorstatus);
}
if(DeviceMode == SD_INTERRUPT_MODE)
{
SDIO_ITConfig(SDIO_IT_DCRCFAIL | SDIO_IT_DTIMEOUT | SDIO_IT_DATAEND | SDIO_IT_RXOVERR | SDIO_IT_RXFIFOHF | SDIO_IT_STBITERR, ENABLE);
}
else if(DeviceMode == SD_DMA_MODE)
{
SDIO_ITConfig(SDIO_IT_DCRCFAIL | SDIO_IT_DTIMEOUT | SDIO_IT_DATAEND | SDIO_IT_RXOVERR | SDIO_IT_STBITERR, ENABLE);
SDIO_DMACmd(ENABLE);
DMA_RxConfiguration(readbuff, BlockSize);
} //DMA配置代码和中断使能代码放这里
SDIO_DataInitStructure.SDIO_DataTimeOut = SD_DATATIMEOUT;
SDIO_DataInitStructure.SDIO_DataLength = BlockSize;
SDIO_DataInitStructure.SDIO_DataBlockSize = (uint32_t) power << 4;
SDIO_DataInitStructure.SDIO_TransferDir = SDIO_TransferDir_ToSDIO;
SDIO_DataInitStructure.SDIO_TransferMode = SDIO_TransferMode_Block;
SDIO_DataInitStructure.SDIO_DPSM = SDIO_DPSM_Enable;
SDIO_DataConfig(&SDIO_DataInitStructure);
TotalNumberOfBytes = BlockSize;
StopCondition = 0;
DestBuffer = readbuff;
/* Send CMD17 READ_SINGLE_BLOCK */
SDIO_CmdInitStructure.SDIO_Argument = (uint32_t)addr;
SDIO_CmdInitStructure.SDIO_CmdIndex = SDIO_READ_SINGLE_BLOCK;
SDIO_CmdInitStructure.SDIO_Response = SDIO_Response_Short;
SDIO_CmdInitStructure.SDIO_Wait = SDIO_Wait_No;
//SDIO_CmdInitStructure.SDIO_Wait = SDIO_Wait_Pend;
SDIO_CmdInitStructure.SDIO_CPSM = SDIO_CPSM_Enable;
SDIO_SendCommand(&SDIO_CmdInitStructure);
errorstatus = CmdResp1Error(SDIO_READ_SINGLE_BLOCK);
if (errorstatus != SD_OK)
{
return(errorstatus);
}
/* In case of single block transfer, no need of stop transfer at all.*/
if (DeviceMode == SD_POLLING_MODE)
{
/* Polling mode */
while (!(SDIO->STA &(SDIO_FLAG_RXOVERR | SDIO_FLAG_DCRCFAIL | SDIO_FLAG_DTIMEOUT | SDIO_FLAG_DBCKEND | SDIO_FLAG_STBITERR)))
{
if (SDIO_GetFlagStatus(SDIO_FLAG_RXFIFOHF) != RESET)
{
for (count = 0; count < 8; count++)
{
*(tempbuff + count) = SDIO_ReadData();
}
tempbuff += 8;
}
}
if (SDIO_GetFlagStatus(SDIO_FLAG_DTIMEOUT) != RESET)
{
SDIO_ClearFlag(SDIO_FLAG_DTIMEOUT);
errorstatus = SD_DATA_TIMEOUT;
return(errorstatus);
}
else if (SDIO_GetFlagStatus(SDIO_FLAG_DCRCFAIL) != RESET)
{
SDIO_ClearFlag(SDIO_FLAG_DCRCFAIL);
errorstatus = SD_DATA_CRC_FAIL;
return(errorstatus);
}
else if (SDIO_GetFlagStatus(SDIO_FLAG_RXOVERR) != RESET)
{
SDIO_ClearFlag(SDIO_FLAG_RXOVERR);
errorstatus = SD_RX_OVERRUN;
return(errorstatus);
}
else if (SDIO_GetFlagStatus(SDIO_FLAG_STBITERR) != RESET)
{
SDIO_ClearFlag(SDIO_FLAG_STBITERR);
errorstatus = SD_START_BIT_ERR;
return(errorstatus);
}
while (SDIO_GetFlagStatus(SDIO_FLAG_RXDAVL) != RESET)
{
*tempbuff = SDIO_ReadData();
tempbuff++;
}
/* Clear all the static flags */
SDIO_ClearFlag(SDIO_STATIC_FLAGS);
}
else if (DeviceMode == SD_INTERRUPT_MODE)
{
while ((TransferEnd == 0) && (TransferError == SD_OK))
{}
if (TransferError != SD_OK)
{
return(TransferError);
}
}
else if (DeviceMode == SD_DMA_MODE)
{
//这里原来放DMA配置和中断使能代码
while (DMA_GetFlagStatus(DMA2_FLAG_TC4) == RESET)
{}
}
return(errorstatus);
}
分析上面代码,发现官方源码是在SDIO开始传送后,DMA才配置,这样做,在高速的CPU上可能没问题,但在103上肯定掉数据,于上就修改成上面的方式,改好后,STemwin终于正常了,至此SD驱动应该完美解决卡死问题
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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SDIO3分频即可,不过12M的USB最快也就1Mbyte/s
---------------------------------
是的,407我测试可以读1Mhz,写也差不多有800KB
103读500KB左右,写只有128KB。
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