Trouble reading SD Card SCR Register with SDIO Peripheral

[dohzer]

Posted on February 01, 2013 at 16:03

I'm trying to read the SD CARD Configuration Register (SCR) on an SD memory card using the SDIO peripheral and I'm not sure if I'm approaching this in the right way, so I'm hoping someone here may have some experience with this.

This register is 64-bits wide, and appears to be read using a normal 'data read' operation, except that normally data is read in a standard block size (512-bytes).If I try to read only 9 bytes (8 data plus 1 CRC), I get an error (the block read throws errors such as CRC failed, etc) and the data FIFO buffer appears to corrupt (all 32-bit words change to the same value).Is there a special way I am meant to configure the Data Path State Machine in order to read this register without causing errors.

[francescatodiego]

Posted on January 30, 2014 at 09:30

rowan have you solved

?

There is a

ST

example

that

explains how to read

the SCR

But I think it

is only

for

SD cards

For HC

or

XC

the memory access

is

block

not

bytes

and

this

confuses me

. This

also applies to

the SDIO_SD_APP_SEND_SCR command

?

[francescatodiego]

Posted on February 10, 2014 at 16:44

This work for me tested with SD 1GB and SDHC 4GB

SDIO_DataInitStructure.SDIO_DataTimeOut = SD_DATATIMEOUT;
SDIO_DataInitStructure.SDIO_DataLength = 8;
SDIO_DataInitStructure.SDIO_DataBlockSize = SDIO_DataBlockSize_8b;
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);
SD_send_command (SDIO_SD_APP_SEND_SCR, 0x00000000, SDIO_Response_Short, SDIO_Wait_No);
sd.opstate = SD_OP_DATABUSCFG04 ;
case SD_OP_DATABUSCFG04:
if (!SD_Cmdreply(SDIO_SD_APP_SEND_SCR, true)) break ;
sd.opstate = SD_OP_DATABUSCFGEND;
if (sd.error != SD_OK) break ;
index = 0 ;
sd.opstate = SD_OP_DATABUSCFG05 ;
case SD_OP_DATABUSCFG05:
while (!(SDIO->STA &(SDIO_FLAG_RXOVERR | SDIO_FLAG_DCRCFAIL | SDIO_FLAG_DTIMEOUT | SDIO_FLAG_DBCKEND | SDIO_FLAG_STBITERR)))
{
if (SDIO_GetFlagStatus(SDIO_FLAG_RXDAVL) != RESET)
{
if (index == 0)
{
SCRrawH = SDIO_ReadData() ;
}
else if (index == 1)
{
SCRrawL = SDIO_ReadData() ;
}
else
{
SDIO_ReadData() ;
}
index++ ;
}
}