Re: 4K sector sizes, I realized today that UIDE, UIDE2,
and UIDEJR likely will NOT be affected at all --
1) DOS has a 64K-byte limit for read/write requests, in
fact 127 sectors of 512 bytes (the "UIDE" drivers do
accept 128). Since 4K-byte sectors "fit" into this
limit, no physical-level driver changes are needed.
2) All 3 "UIDE" drivers do ONLY physical block I-O and
"know nothing" about directories, file systems, etc.
The drivers remain "DOS independent", i.e. they just
read/write sectors "at the orders" of the DOS system
and user programs. MUCH simpler and a LOT smaller!
3) UIDE/UIDE2 require, and UIDEJR can set, a 64K buffer
in XMS memory for "misaligned" or other I-O unsuited
to UltraDMA. Since DOS cannot do more than 64K I-O
at a time, no change to the "UIDE" drivers' UltraDMA
buffering is needed.
4) UIDE/UIDE2 set cache blocks of varying sizes, 8K for
a 5-MB cache, up thru 64K for an 80-MB+ cache. So,
the drivers have enough cache blocks in all cases to
be effective, in handling both directory sectors and
data files. 4K disk sectors "fit" evenly, into any
UIDE/UIDE2 cache-block size same as 512-byte sectors
do. So UIDE/UIDE2 will need NO changes for caching
the larger disk sectors!
About all that MAY be needed in the 3 "UIDE" drivers is
some init logic to "select" using 4K-byte sectors, if a
hard-disk demands this (FOOLISH if so, in my opinion!).
Assuming "boot" or FDISK/FORMAT problems are dealt with
as required, my comment about 4K-byte sectors is "Bring
'em on"! The 3 "UIDE" drivers will run fine with them
and so "regular" DOS I-O should not be any problem!
[In the U.S.A., we have an old engineering "joke" known
as the "K.I.S.S. Principle", whose letters denote "Keep
it SIMPLE, stupid!". Less and less of a JOKE, as time
goes by and computers become unjustifiably COMPLEX! I
and the "UIDE" drivers still OBEY the "KISS Principle",
insofar as is possible!].
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