Command: UDVD2.SYS
UDVD2 is a CD/DVD driver for up to 4 SATA, IDE, or old PIO-mode drives.
It reads CD/DVD data files, plays audio CDs, and can read "raw" (track-
writer) data. UDVD2 can work alone; or if the caching UHDD is in use,
UDVD2 calls it to cache CD/DVD data files and directories (audio/track-
writing is uncached). UDVD2 takes 128K of XMS as its buffer for input
unsuited to UltraDMA. It shares UHDD's buffer, or it will set its own
buffer if UHDD is unused.
Syntax:
DEVICE[HIGH] = [path] UDVD2.SYS [/A] [/D:DeviceName] [/H] [/Rnn][/UX]
Options:
UDVD2 usually needs only a /H switch to use "free HMA" and a /D: switch
to set its "device name" for SHSUCDX / (MSCDEX). All UDVD2 switches are:
/A See /A for UHDD.
/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.
/H See /H for UHDD, above.
/Rnn See /R for UHDD, above.
/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.
Comments:
For all switches in each driver, a dash may replace the slash and lower
case letters may be used if desired.
UHDD and UDVD2 are Closed-Source DOS drivers for PCs with an 80386+
CPU (UHDD requires an 80486+ CPU) and using MS-DOS V5.0+ or a
fully compatible variant.
The latest UHDD and UDVD2 are Open Source device drivers for PCs with
an 80386+ CPU and using FreeDOS, whereas at XMGR, RDISK it depends on
the version number if it is Open Source or Closed Source.
For more information and if you are in doubt, read "README.txt" in
"drivers.zip".
Examples:
Comment: There are new closed source drivers for UHDD.SYS (=XHDD.SYS)
and UVD2.SYS (=XDVD2.SYS) which may have other options. So please do
not rely on the options in the examples!
A) A small real-mode system that needs only XMS may use this
CONFIG.SYS/FDCONFIG.SYS example file:
..
..
DOS=HIGH
DEVICE=C:\BIN\XMGR.SYS /Rnn ;R if DOS "games" need it
..
.. Int 13h drivers cached by UHDD load now.
..
DEVICE=C:\BIN\UHDD.SYS /S20 /H /O ;Min. 20 MB recommended
DEVICE=C:\BIN\UDVD2.SYS /D:BLURAY1 /H ;Must load after UHDD
DEVICE=C:\BIN\RDISK.COM /S5 /F ;Optional. If not used,
; UHDD/UDVD2 can issue /F
..
.. Further CONFIG.SYS commands can be given here.
..
B) Real-mode systems with V3.70+ UMBPCI and XMGR do not need the LOWDMA
driver, as XMGR has an "I-O Catcher" for UMBPCI. This scheme takes
NO low memory if /W can be used (MS-DOS etc.) or only 544 low memory
bytes without /W (PC-DOS etc.). XMGR and other drivers load direct
to UMBPCI "Shadow RAM"! Systems which permit multiple providers of
upper memory (MS-DOS, PC-DOS, etc.) can also load an "EMM" driver as
shown below, to map the B000-B7FFh "Monochrome Graphics" area as 32K
more upper memory. An example CONFIG.SYS file is:
..
..
DOS=HIGH,UMB
DEVICE=C:\BIN\UMBPCI.SYS
DEVICE=C:\BIN\XMGR.SYS /W /Rnn ;W only when permitted!
;R <= 15.5 MB with JEMM!
DEVICE=C:\BIN\JEMM386.EXE I=B000-B7FF X=C800-EFFF ... ;Optional
..
.. Int 13h drivers cached via UHDD load now
.. and can be loaded in UMBPCI upper memory.
..
DEVICEHIGH=C:\BIN\UHDD.SYS /S200 /H /O ;Fast 200 MB cache
DEVICEHIGH=C:\BIN\UDVD2.SYS /D:CDROM1 /H ;Must load after UHDD
DEVICEHIGH=C:\BIN\RDISK.COM /S50 /F ;Optional. If unused,
; UHDD/UDVD2 can issue /F
..
.. Further CONFIG.SYS commands can be given here.
..
C) A protected-mode system with XMGR and an "EMM" driver can use XMGR's
"boot", taking a minimum 304 bytes of low memory for a 24-entry "XMS
Handles" table, plus any low memory the "EMM" driver may need. A
CONFIG.SYS example file is:
..
..
DOS=HIGH,UMB
DEVICE=C:\BIN\XMGR.SYS /B /N24 /R15.5 ;24 Handle XMGR "boot"
;R <= 15.5 MB with JEMM!
DEVICE=C:\BIN\JEMM386.EXE I=B000-B7FF ...
DEVICEHIGH=C:\BIN\XMGR.SYS ;Loads the runtime XMGR
..
.. Int 13h drivers cached by UHDD load
.. now and can load into upper memory.
..
DEVICEHIGH=C:\BIN\UHDD.SYS /S400 /H /O /P ;Optimal 400 MB cache
DEVICEHIGH=C:\BIN\UDVD2.SYS /D:MYDVD /H ;Must load after UHDD
DEVICEHIGH=C:\BIN\RDISK.COM /S125 /F ;Optional. If unused,
; UHDD/UDVD2 can issue /F
..
.. Further CONFIG.SYS commands can be given here.
..
In each example above, UDVD2 must load after UHDD, so UDVD2 will "find"
UHDD in memory and call it for CD/DVD file caching.
Users that need RDISK with a specific drive letter may delay loading it
until AUTOEXEC.BAT is run. If /F or /G are also needed for DOS games,
RDISK must issue them from AUTOEXEC, since it is then the last of these
drivers to load. Whenever RDISK is used, AUTOEXEC.BAT must also issue
commands to copy all RDISK programs and data up to the RAM-disk, as XMS
memory is LOST when PCs shut down! Such copies require little time.
If UHDD and RDISK will both run, users must balance how much XMS memory
the drivers take. UHDD can set a 400-MB cache, as in example C above,
and RDISK can request 125-MB of XMS for its programs, "fast" data files
and compiler TEMP files. Such sizes should be optimal on most systems
but can be adjusted up or down, as desired. All remaining XMS memory
is left free for use by other programs. The basic "plan" is for RDISK
to hold programs and high-speed files, while UHDD then caches "regular"
data files. Properly balanced use of XMS memory will give a VERY fast
DOS system!
See also:
autoexec.bat/fdauto.bat
config.sys/fdconfig.sys
device/devicehigh
devload
dos
(fdxms)
(fdxms286)
(gcdrom.sys)
himemx
jemm386
jemmex
lastdrive/lastdrivehigh
rdisk
rdiskon
shsucdx
tdsk
uhdd.sys
uide.sys
xmgr.sys
Copyright © 2018 - 2022 Jack Ellis, updated 2022 by W. Spiegl.
This file is derived from the FreeDOS Spec Command HOWTO.
See the file H2Cpying for copying conditions.