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Re: Hitachi 1TB HDD's, NetBSD 6.0.1 and RAID1 - soft errors and clicking noises!
On Jun 30, 3:59am, Greg Troxel wrote:
} Carl Brewer <carl%bl.echidna.id.au@localhost> writes:
} > The funny part to my eye us the start at 2048 not 63? Is that right?
} 63 is leftover from when floppies actually had 63 sectors per track.
No it isn't. First, I don't know of any floppies off the top of
my head that had 63 sectors per track. The original 360K PC floppy
only had 9 sectors per track. Secondly, floppies didn't have partition
This actually comes from the MBR (which arrived on the scene with
MS-DOS 2.0 if I recall correctly). The MBR used a packed structure to
represent the start and end of each partition in CHS
(Cylinder/Head/Sector) format. In this structure one 16-bit word was
divided into 10 bits for cylinder and 6 bits for sectors per track.
Interestingly the structure allocated 8 bits for heads. The
interesting thing is that if I recall correctly (I don't have time to
look it up at the moment), the hardware at the time only allowed 4 bits
for the head number.
}-- End of excerpt from Greg Troxel
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