microSD partition table and proper heads/sectors/cylinders # ?

Olivier Berger oberger at ouvaton.org
Sun Sep 21 19:44:37 CEST 2008


Hi.

I noticed that initially, my 2GB microSD card was displaying :
# fdisk -l /dev/mmcblk0

Disk /dev/mmcblk0: 2032 MB, 2032664576 bytes
64 heads, 63 sectors/track, 984 cylinders
Units = cylinders of 4032 * 512 = 2064384 bytes

        Device Boot      Start         End      Blocks  Id System
/dev/mmcblk0p1               1         984     1983619+  6 FAT16

After Debian installer's partitioning step, it becomes :
# fdisk -l /dev/mmcblk0

Disk /dev/mmcblk0: 2032 MB, 2032664576 bytes
4 heads, 16 sectors/track, 62032 cylinders
Units = cylinders of 64 * 512 = 32768 bytes

        Device Boot      Start         End      Blocks  Id System
/dev/mmcblk0p1               1         245        7832  83 Linux
/dev/mmcblk0p2             246       62032     1977184  83 Linux

Is there any rationale for the heads/sectors/cylinders difference ?

I'm not sure this is something that matters as I never really tried
and figure how the microSD memory to "disk" mapping is done.

Thanks in advance for any hints.

Best regards,
-- 
Olivier BERGER 
(OpenPGP: 1024D/B4C5F37F)
http://www.olivierberger.com/weblog/



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