Johnson Lam has posted a new DRIVERS.ZIP file, now dated 19-Oct-2014 and
with an updated UHDD driver, in his "dropbox" at:


No change to any of the other drivers but re-dating them 19-Oct-2014 for
consistency, also no change to the /B "stand alone" UHDD.

UHDD's /M switch is deleted.   It shall now set a 256-byte binary search
buffer, not 512.   The short buffer still avoids 6 XMS accesses in every
cache binary search, which increases speed.   It also helps UHDD + UDVD2
(4400 HMA bytes total) fit in the limited HMA of V7.0+ MS-DOS (max. 8976
bytes) with up to 12 DOS buffers.   For these reasons, UHDD's buffer has
been made permanent, and /M is now unneeded.

UHDD now overlaps caching tasks with UltraDMA disk I-O!   Disk input may
not be overlapped, as at least one extra XMS move is needed (user-buffer
to cache, or vice-versa, depending on UltraDMA "rules").   That move may
not begin until input is finished.   But, disk output CAN be overlapped,
and an extra XMS move (if needed) can be done during output DMA!

Adding only UltraDMA output overlap, and doing some cache work after DMA
end but before disk "ready", i.e. in the last inter-sector "gap" of each
disk I-O, all WORKED the very first time!   UHDD now has noticeably more
speed!   This is especially true for slower laptop or "old" disks, whose
sector "gaps" give UHDD more time to overlap XMS binary searches, etc.

More difficult to add in UIDE, with its integrated logic, while UHDD has
separate stand-alone and caching UltraDMA subroutines.   Many UIDE users
want the driver to remain as-is, so it was again left alone.   Those who
desire more speed can switch from using UIDE to using UHDD + UDVD2.

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