Command: uide.sys

  UIDE.SYS is a DOS "Universal IDE" caching driver, which
  supports IDE and SATA-HDs, CD and DVD.
  UIDE.SYS has to be loaded in CONFIG.SYS / FDCONFIG.SYS.
  When FreeDOS is already running, you can load UIDE.SYS
  later with DEVLOAD.


  DEVICE = [path] UIDE.SYS [/A] [/B] [/D:DeviceNm] [/E] [/H] [/N1]
           [/N2] [/N3] [/N4] [/Q] [/Rnn] [/Snnnn] [/UX] [/Z]
  DEVICEHIGH = [path] UIDE.SYS [/A] [/B] [/D:DeviceNm] [/E] [/H] [/N1]
               [/N2] [/N3] [/N4] [/Q] [/Rnn] [/Snnnn] [/UX] [/Z]


  UIDE usually needs only a /H switch to use HMA space and a /S switch to
  specify its cache size. All UIDE switches are as follows:
  /A    Requests "alternate" addressing for "legacy" IDE controllers,
        01E8h/0168h for the first one, 01F0h/0170h for the second.
        /A is rarely needed. Without /A, the first "legacy" con-
        troller will use 01F0h/0170h and a second uses 01E8h/0168h
        as is usual for PC mainboards.
  /B    Requests a "basic" UltraDMA driver for disks and CDs/DVDs, no
        caching nor diskette handling. The /B driver can request
        128K of XMS for an UltraDMA I-O buffer, and it can load in
        the HMA.
  /D:   Specifies the "device name" used by the CD/DVD Redirector to
        access CD/DVD drives, e.g. /D:CDROM1 /D:SANYO1 etc.
        If /D: is omitted, or the name following a /D: is missing
        or invalid, UDVD1 is set by default.
  /E    Makes the driver call the BIOS for any hard disk I-O request.
        /E avoids setup trouble on some DOS emulators (VirtualBox,
        etc.) that do not emulate all PC hardware logic! /E also
        allows using hard disks on 1994 or older PCs which have no
        UltraDMA or no PCI/EDD BIOS. /E still caches disk data,
        unlike /N1 that removes ALL disk logic! If /B is given,
        /E is ignored.

  Using /E on protected-mode systems (JEMM386 etc.) may LOSE
  much speed, as a newer BIOS may omit "Virtual DMA" support
  and force disks to run in PIO mode! If /E is required, a
  DOS system should run in real-mode (UMBPCI, etc.) whenever
  /H    Puts most of the driver in "free HMA" space. To use /H, the
        driver must load from FDAUTO.BAT (not FDCONFIG.SYS), since
        FreeDOS provides no "free HMA" until FDAUTO is run.
  /N1   Requests NO hard-disk handling by the driver.
  /N2   Requests NO CD/DVD handling by the driver.
  /N3   Requests no XMS memory. /N3 sets UIDE's /B "basic" driver.
        /N3 requires loading in LOW memory, or UIDE aborts! /N3
        can LOSE much speed, as misaligned or other I-O unsuitable
        for UltraDMA requires calling the BIOS for a disk or using
        PIO-mode for CD/DVD drives!
  /N4   See /Z below.
  /Q    Awaits "data request" before starting UltraDMA I-O transfers.
        /Q is rarely needed, only for old systems where the driver
        loads O.K. but seems unable to transfer data. /Q is NOT
        for use with Sabrent or other SATA-to-IDE adapters that do
        not emulate "data request"!
  /R15  "Reserves" 15-MB or 63-MB of XMS, for old DOS "game" programs
  /R63  which require XMS memory below 16- or 64-MB. The drivers
        must be able to reserve this memory, reserve their own XMS
        memory beyond that, and then "free" the 15/63-MB XMS. If
        not, the drivers display "XMS init error" and abort! /R
        for UDVD2 is ignored if it loads after UHDD, as UDVD2 will
        then "share" UHDD's XMS memory.
  /Snn  Specifies the desired cache size, in megabytes of XMS memory.
        Values for /S can be 5, 10, 15 or any number from 20 thru
        4093 (4 Gigabytes). When /S is omitted/invalid, a 20-MB
        cache is set. UIDE displays "XMS init error" and aborts,
        if not-enough XMS memory is free! If so, a smaller cache
        must be requested.
  /UX   Disables all CD/DVD UltraDMA, even for units that can do it.
        All CD/DVD data input then uses PIO-mode. /UX is rarely
        needed, only for odd drives that do not obey ATAPI rules.
        /UX does not affect hard disks.
  /Z    Moves protected-mode XMS data in 8K blocks (not 64K) for 486+
        CPUs and 4K blocks for slower 386 CPUs. With JEMM386, /Z
        is unneeded. When other EMM/VCPI/DPMI drivers are used,
        PCs must be tested to find if /Z is needed. BAD schemes,
        that allow not-enough interrupts during an XMS move, could
        still be in use!
  For all switches, a dash may replace the slash and lower case letters
  may be used if desired.


  UIDE is an Open Source DOS disk caching driver for a PC system with an
  80386+ CPU and using FreeDOS. It traps BIOS "Int 13h" I-O and caches
  data for up to 22 BIOS disks of any size on up to 9 "Legacy" and Native
  PCI SATA/IDE controllers. It calls the BIOS to run A: or B: diskettes
  and caches data for other Int 13h drivers which load first. UIDE also
  runs up to 4 CD/DVD drives, including old PIO-mode types (no UltraDMA),
  and caches their data files and directories for FAR faster speed (audio
  or trackwriting is uncached). UIDE's cache is in XMS memory and holds
  up to 4 Gigabytes of data. Its /B switch also sets a "basic" UltraDMA
  disk driver (no cache) which can use 128K of XMS to buffer I-O unsuited
  to UltraDMA. The basic UIDE is for tests and other non-cached work.


  A)  Small real-mode systems that need only XMS may use this FDCONFIG.SYS
      example file:
          ..  Etc.
  B)  Real-mode systems with V3.70+ UMBPCI and XMGR do not need the LOWDMA
      driver, as XMGR sets an "I-O Catcher" for UMBPCI. This scheme uses
      NO low memory, if /W is given; XMGR and other drivers go directly to
      UMBPCI "Shadow RAM" upper memory! An example FDCONFIG.SYS file is:
          ..  Etc.
  C)  A protected-mode system with XMGR and JEMM386 can use XMGR's "boot",
      taking only 384 low memory bytes as its 32-entry "XMS Handles" table
      (used early by JEMM386). An example FDCONFIG.SYS file is:
        DEVICE=C:\FREEDOS\BIN\XMGR.SYS /B /N32     ;32 Handle XMGR "boot"
        DEVICEHIGH=C:\FREEDOS\BIN\XMGR.SYS         ;Loads the runtime XMGR
          .. Etc.
  When all above drivers are loaded, other needed FDCONFIG.SYS files such
  as SETVER, ANSI.SYS, etc. can then load in any desired order.
  For each of the above examples, FDAUTO.BAT can then load UHDD and UDVD2
  (or just UIDE) using the DEVLOAD program. This permits the drivers to
  use "free HMA" and save low memory. UDVD2 must load after UHDD, so it
  will find UHDD in memory and "link" to it for CD/DVD data file caching.
  Example FDAUTO command lines are:
          ..  Int 13h drivers cached thru UHDD/UIDE
          ..  load now and can load in upper memory.
        DEVlOAD /H C:\FREEDOS\BIN\UHDD.SYS /S500 /H /O     ;Or UIDE alone
        LH C:\FREEDOS\BIN\RDISK.COM /S250                  ;Optional
          ..  Etc.

See also:


  Copyright © 2007-2021 Jack Ellis, updated 2022 by W. Spiegl.

  This file is derived from the FreeDOS Spec Command HOWTO.
  See the file H2Cpying for copying conditions.