Another DOS Format issue with MMC/SD

Gene Smith gds at
Mon Jan 26 17:37:17 UTC 2009

Thomas Doerfler wrote:
> Gene,
> it makes a big difference whether you format /dev/sd-card-a or
> /dev/sd-card-a1.
> The former will format the whole disk as a MSDOS filesystem (sometimes
> called a "superfloppy"), this means, that the partition table residing
> in the first sectors is overwritten with msdos information.
> The later will format partition 1 of the sdcard, still leaving the
> partition table intact.
> Possibly you might do the same thing with linux....

Same result when fmt in rtems as /dev/sd-card-a1
Tried mkdosfs -F16 -n "" /dev/sdc
in linux. Says you can't do the whole device w/o -I.
-I is for formatting MO disks as super floppy as you say. MO = magneto 
optical, e.g., zip drives I think.

> wkr,
> Thomas.

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