João Jerónimo wrote:
> Alex Buell wrote:
>> So, I wrote a tiny utility program in NASM to get the disk parameters
>> via the int 0x13 / AH = 8. The parameters it re****te are correct for
>> the hard disks connected to my PC's motherboard, but when it queried
>> the BIOS for the parameters of its SATA hard disk, it re****ted: 16
>> heads, 1022 cylinders and 63 sectors. Ah! That's why MSDOS couldn't
>> create partitions larger than 503MB!
>
> If you access a HD using BIOS w/CHS, you'll never access past 8GB. If
the
> BIOS' (or driver's) routines don't sup****t the more recent CHS feature
that
> allows it to map "big" disks to a virtual CHS geometry, you'll be even
more
> limited.
>
> As someone pointed already, it's pretty likely that MS-DOS 6.22 does not
> sup****t LBA routines, so it'll use CHS (which implies a maximum of 8GB).
If
> the SATA BIOS does not sup****t the virtual mapping I mentioned above in
> it's CHS-based routines, then you'll be even more limited (I think it's
the
> case).
>
Not just "pretty likely". LBA sup****t was added in Windows 95 OSR2,
which I believe is MS-DOS 7.10.
-hpa
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