MBR or not in SD cards?

Question

Most formatted SD cards I have examined have a master boot record in sector zero which points to one or more partition/volume records that contain everything you need to know about how the partition/volume is set up. IOW, they're set up like hard drives. However, I found one card (a Dane-Elec 128 MB) that has no MBR - the (only) partition/ volume boot record is in sector zero, like floppy disks. I suspect there are others sold this way.

Is there such a thing as a "simple" "standard" way to identify the difference by examining the contents of the card?

-- Silvar Beitel

John Speth · Accepted Answer

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Silvar Beitel · Answer

On Jul 9, 2:23 pm, I wrote:

CBFalconer · Answer

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Stefan Reuther · Answer

You read the CSD register of the card. It tells you whether the card is to be formatted as "superfloppy" or "hard disk".

SD 2.0 requires all cards to be formatted as hard-disk with a FAT partition, so I'd expect new cards all to be in this format.

Stefan

Silvar Beitel · Answer

Ah!  Thanks, Stefan.  Just what I was looking for - I'd forgottenabout that.(P.S. Thanks, Chuck, for the pointers to USENET providers.)--Silvar Beitel

Antti · Answer

onehmm...I would say it makes sense to verify the format type regardless of thesettingsfor better compliancewinXP as example will reformat a sd card that had partitions after mbrcrash as big floppy IMHOso it order to read those cards it is necessary to read in sector 0and parse itAntti

MBR or not in SD cards?

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