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MBR or not in SD cards?

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

Reply to
Silvar Beitel
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On Jul 9, 2:23 pm, I wrote:

Reply to
Silvar Beitel

I think google groups sucks too. I recommend using "nntp.aioe.org" instead. It's free and the spam repellent policy is very effective. You can post too. The downside is the retention capacity is tiny compared to for-pay NG servers.

JJS

Reply to
John Speth

Some free news servers. I use motzarella, teranews and gmane. (1 time charge) (free) (free) (free) (free) (free) (mail-lists via news) (free) (pay)

Reply to
CBFalconer

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

Reply to
Stefan Reuther

Ah! Thanks, Stefan. Just what I was looking for - I'd forgotten about that.

(P.S. Thanks, Chuck, for the pointers to USENET providers.)

-- Silvar Beitel

Reply to
Silvar Beitel

one

hmm...

I would say it makes sense to verify the format type regardless of the settings for better compliance

winXP as example will reformat a sd card that had partitions after mbr crash as big floppy IMHO so it order to read those cards it is necessary to read in sector 0 and parse it

Antti

Reply to
Antti

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