[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: unable to repartition SD card from Android phone



>
> Does you SD card and/or SD card adapter have a write-protect tab or other
> such mechanism?  If so, put it in the unlocked position.

The micro SD cards used in phones don't appear to have such
mechanisms, but your point is well taken; viz. I've not adequately
checked the hardware path (MB, card reader, etc. red-faced here...)

>
> Have you tried using dd to wipe the first megabyte (including the partition
> table)?
>
> # dd if=/dev/zero of=/dev/sdc count=2048; sync
>

Yes, but no effect. Even count=1 gets to non-zero bytes:

dd if=/dev/sdc count=1 | od -b
0000000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000
*
0000700 002 000 356 377 377 377 001 000 000 000 377 043 267 003 000 000
0000720 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000
*
0000760 000 000 000 000 000 000 000 000 000 000 000 000 000 000 125 252
1+0 records in
1+0 records out
0001000
512 bytes (512 B) copied, 0.00365101 s, 140 kB/s

dd if=/dev/zero of=/dev/sdc count=1; sync
1+0 records in
1+0 records out
512 bytes (512 B) copied, 0.0170507 s, 30.0 kB/s

 dd if=/dev/sdc count=1 | od -b
0000000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000
*
0000700 002 000 356 377 377 377 001 000 000 000 377 043 267 003 000 000
0000720 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000
*
0000760 000 000 000 000 000 000 000 000 000 000 000 000 000 000 125 252
, 0.00290682 s, 176 kB/s
1+0 records in
1+0 records out
512 bytes (512 B) copied
0001000

Maybe I'm not looking at this right...

The idea that a card could be locked up by the OS is titillating but
improbable. There would have to be an (apparently) unpublished trap
door or a back door to the disk controller in a generic disk.  So it's
gotta be hardware and this has all been noise.


Reply to: