Do we still need ATA disk CHS addressing?

Takahashi Yoshihiro nyan at
Sun Aug 9 11:25:56 UTC 2009

In article <4A7DF076.4070203 at>
Alexander Motin <mav at> writes:

> While preparing wrapping ATA(4) low-level drivers code into CAM SIM, I
> would like to remove CHS addressing support to make code cleaner. CHS
> addressing is officially declared obsoleted and replaced by LBA. Since
> ATA/ATAPI-6 specification (October 2001) it is even no longer
> documented.
> Have anybody seen ATA drive without LBA support in last years?
> Any other objections against removing it?

PC98 uses CHS addressing because the internal interface works for very
old HDD only, so I hope it remains if possible.  But if you need a lot
of works for CHS support, I agree to remove it.

TAKAHASHI Yoshihiro <nyan at>

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