SD Card Going Crazy

DavidZemon

I've had this problem before... I can't remember what the solution was. It's driving me crazy though

The attached screenshot is the reset command: 0x40 0x00000000 0x95. Immediately preceding the command (you can see the tail end of it) is the power up sequence many times over (24 bits, 128 times).

What the heck causes an SD card to go schizo like this?

Cluso99

Do you have a 10uF across the power and ground at the socket?

DavidZemon

It's the DNA board. Not sure

Peter Jakacki

I see similar behaviour with some brands of SD cards but not SanDisk. Try different brands and see if it still happens. If you bought grey market SanDisk then they might not be SanDisk but you should be able to read the CID fields etc to confirm chip manufacturer as SD (SanDisk) and model.

EDIT: Here's the info from a 4GB SanDisk

.CARD 
MFG             03
OEM             SD
PID             SD04G
REV             80
S/N             71CC.0203
DATE            2011/11
CRC             2E
  CSD REGISTER  
*SDHC CARD* 
TACC            100ns
NSAC            0bps
TRANS           50MHz
BLKLEN          512
SIZE            3781MB

and here's a card that can cause some problems

.CARD 
MFG             27
OEM             PH
PID             SD04G
REV             20
S/N             035E.06B0
DATE            2011/4
CRC             66
  CSD REGISTER  
*SDHC CARD* 
TACC            100ns
NSAC            0bps
TRANS           50MHz
BLKLEN          512
SIZE            3775MB