Windows 95 CD-ROM Msdosdrv.txt File (2 of 2)

• Microsoft Windows 95

SUMMARY

This article contains a partial copy of the information in the Msdosdrv.txt file from the Windows 95 CD-ROM. This article is the second of two articles.

MORE INFORMATION

         Microsoft Windows 95 README for MS-DOS Device Drivers
                               August 1995

               (c) Copyright Microsoft Corporation, 1995

DBLBUFF.SYS -- Double Buffering

Loads the Dblbuff.sys device driver to perform double buffering. Double buffering provides compatibility for certain hard-disk controllers that cannot work with memory provided by EMM386 or Windows running in 386 Enhanced mode.

If Windows Setup determined that your system may need double- buffering, it will add a DoubleBuffer=1 entry to the [Options] section of Msdos.sys, which will automatically load Dblbuff.sys. To manually enable double-buffering, you can either add the above entry to Msdos.sys, or add a DEVICE command in your CONFIG.SYS file.

Syntax

    DEVICE=[drive:][path]DBLBUFF.SYS [/D+]

[drive:][path]

   Specifies the location of the Dblbuff.sys file.

   Instructs Dblbuff.sys to double-buffer all disk I/O all the time.
   By default, it will only double-buffer I/O to UMBs, and it will
   automatically stop double-buffering if it appears to be
   unnecessary.

DISPLAY.SYS

Enables you to display international character sets on EGA, VGA, and LCD monitors. This device driver must be loaded by a DEVICE or DEVICEHIGH command in your CONFIG.SYS file.

Syntax

    DEVICE=[drive:][path]DISPLAY.SYS CON[:]=(type[,[hwcp][,n]])

    DEVICE=[drive:][path]DISPLAY.SYS CON[:]=(type[,[hwcp][,(n,m)]])

[drive:][path]

    Specifies the location of the DISPLAY.SYS file.

   Specifies the display adapter in use. Valid values include EGA and
   LCD. The EGA value supports both EGA and VGA display adapters. If
   you omit the type parameter, DISPLAY.SYS checks the hardware to
   determine which display adapter is in use. You can also specify CGA
   and MONO as values for type, but they have no effect because
   character-set switching is not enabled for these devices.

   Specifies the number of the character set that your hardware
   supports. The following list shows the character sets that MS-DOS
   supports and the country or language for each:

     437    United States
     850    Multilingual (Latin I)
     852    Slavic (Latin II)
     860    Portuguese
     863    Canadian-French
     865    Nordic

   Additional character sets are supported by the EGA2.CPI and
   EGA3.CPI files.

   Specifies the number of character sets the hardware can support in
   addition to the primary character set specified for the hwcp
   parameter.
   Valid values for n are in the range 0 through 6. This value depends
   on your hardware. For EGA display adapters, the maximum value for n
   is 6; for LCD display adapters, the maximum value for n is 1.

   Specifies the number of subfonts the hardware supports for each
   code page. The default value is 2 if type is EGA, and 1 if type is
   LCD.

DRVSPACE.SYS, DBLSPACE.SYS

Determines the final memory location of DRVSPACE.BIN or DBLSPACE.BIN, the part of MS-DOS that provides access to your compressed drives.

DxxSPACE.SYS loads the real-mode driver into upper memory blocks. This can save 60K of conventional memory when you run Windows 95 in real mode, and can save 100K or more if you use Microsoft Plus! for Windows.

When you start your computer, Windows loads DRVSPACE.BIN or DBLSPACE.BIN along with other operating-system functions, before carrying out the commands in your CONFIG.SYS and AUTOEXEC.BAT files. DxxSPACE.BIN initially loads in conventional memory because it loads before device drivers that provide access to upper memory.

When you use DriveSpace or DoubleSpace to create a compressed drive on your computer, the program adds a command for DxxSPACE.SYS to your CONFIG.SYS file.

In the following syntax, for DxxSPACE type the filename for the program you are using.

Syntax

   DEVICE=[drive:][path]DxxSPACE.SYS /MOVE [/NOHMA] [/LOW]

   DEVICEHIGH=[drive:][path]DxxSPACE.SYS /MOVE [/NOHMA] [/LOW]

/MOVE

   Moves DxxSPACE.BIN to its final location in memory.

   Initially, DxxSPACE.BIN loads at the top of conventional memory.
   After Windows finishes carrying out the commands in the CONFIG.SYS
   file, it moves DxxSPACE.BIN to the bottom of conventional memory.
   When DxxSPACE.SYS is loaded by using the DEVICE command, it moves
   DxxSPACE.BIN from the top of conventional memory to the bottom.
   This can be useful for avoiding conflicts with programs that are
   loaded from the CONFIG.SYS file and require access to the top of
   conventional memory.

   When DxxSPACE.SYS is loaded by using the DEVICEHIGH command,
   DxxSPACE.BIN moves to upper memory, if available. Moving
   DxxSPACE.BIN to upper memory makes more conventional memory
   available.

   Prevents DxxSPACE.SYS from moving a portion of DxxSPACE.BIN to the
   high memory area (HMA).

   If MS-DOS is loaded into the HMA, DxxSPACE.SYS moves a  portion of
   DxxSPACE.BIN to the HMA (if there is enough room in the HMA). Use
   this switch if you do not want DxxSPACE.BIN to use the HMA.

   Prevents DxxSPACE.SYS from loading at the top of conventional
   memory. Use this switch if you have an MS-DOS-based program that
   does not support DriveSpace or DoubleSpace at the top of
   conventional memory. Note that use of this switch will prevent
   Windows from reusing the memory occupied by DxxSPACE.sys.

[drive:][path]

   Specifies the location of the DxxSPACE.SYS file.

EGA.SYS

Saves and restores the display when the MS-DOS Shell Task Swapper is used with EGA monitors. If you have an EGA monitor, you must install the EGA.SYS device driver before using Task Swapper. This device driver must be loadedby a DEVICE or DEVICEHIGH command in your CONFIG.SYS file.

Syntax

   DEVICE=[drive:][path]EGA.SYS

[drive:][path]

   Specifies the location of the EGA.SYS file.

EMM386.EXE

Provides access to the upper memory area and uses extended memory to simulate expanded memory. This device driver must be loaded by a DEVICE command in your CONFIG.SYS file and can be used only on computers with an 80386 or higher processor.

EMM386 uses extended memory to simulate expanded memory for programs that can use expanded memory. EMM386 also makes it possible to load programs and device drivers into upper memory blocks (UMBs).

Syntax

    DEVICE=[drive:][path]EMM386.EXE [ON|OFF|AUTO] [memory] [MIN=size]
    [W=ON|W=OFF] [Mx|FRAME=address|/Pmmmm] [Pn=address] [X=mmmm-nnnn]
    [I=mmmm-nnnn] [B=address] [L=minXMS] [A=altregs] [H=handles]

    [RAM=mmmm-nnnn] [NOEMS] [NOVCPI] [HIGHSCAN] [VERBOSE] [WIN=mmmm-

    [NOHI] [ROM=mmmm-nnnn] [NOMOVEXBDA] [ALTBOOT] [NOBACKFILL]

[drive:][path]

   Specifies the location of the EMM386.EXE file.

   Activates the EMM386 device driver (if set to ON), or suspends the
   EMM386 device driver (if set to OFF), or places the EMM386 device
   driver in auto mode (if set to AUTO). Auto mode enables expanded-
   memory support and upper memory block support only when a program
   calls for it. The default value is ON. Use the EMM386 command to
   change this value after EMM386 has started.

   Specifies the maximum amount of extended memory (in kilobytes) that
   you want EMM386 to provide as expanded/Virtual Control Program
   Interface (EMS/VCPI) memory. This amount is in addition to the
   memory used for UMBs and EMM386 itself. Values for memory are in
   the range 64 through the lesser of either 32768 or the amount of
   extended memory available when EMM386 is loaded. The default value
   is the amount of free extended memory. If you specify the NOEMS
   switch, the default value is 0. EMM386
   rounds the value down to the nearest multiple of 16.

MIN=size

   Specifies the minimum amount of EMS/VCPI memory (in kilobytes) that
   EMM386 will provide, if that amount of memory is available. EMM386
   reserves this amount of extended memory for use as EMS/VCPI memory
   when EMM386 is loaded by the DEVICE=EMM386.EXE command in your
   CONFIG.SYS file. EMM386 may be able to provide additional EMS/VCPI
   memory (up to the amount specified by the MEMORY parameter) if
   sufficient XMS memory is available when a program requests EMS/VCPI
   memory. Values are in the range 0 through the value specified by
   the MEMORY parameter. The default value is 256. If you specify the
   NOEMS switch, the default value is 0. If the value of MIN is
   greater than the value of MEMORY, EMM386 uses the value specified
   by MIN.

   Enables or disables support for the Weitek co-processor. The
   default setting is W=OFF.

   Specifies the address of the page frame. Valid values for x are in
   the range 1 through 14. The following list shows each value and its
   associated base address in hexadecimal format:

           1 => C000h     8 => DC00h
           2 => C400h     9 => E000h
           3 => C800h    10 => 8000h
           4 => CC00h    11 => 8400h
           5 => D000h    12 => 8800h
           6 => D400h    13 => 8C00h
           7 => D800h    14 => 9000h

   Values in the range 10 through 14 should be used only on computers
   that have 512K of memory.

   Specifies the page-frame segment base directly. To specify a
   specific segment-base address for the page frame, use the FRAME
   switch, and specify the address you want. Valid values for address
   are in the ranges 8000h through 9000h and C000h through E000h, in
   increments of 400h. To provide expanded memory and disable the page
   frame, you can specify FRAME=NONE; however, this may cause some
   programs that require expanded memory to work improperly.

   Specifies the address of the page frame. Valid values for mmmm are
   in the ranges 8000h through 9000h and C000h through E000h, in
   increments of 400h.

   Specifies the segment address of a specific page, where n is the
   number of the page you are specifying and address is the segment
   address you want. Valid values for n are in the range 0 through
   255. Valid values for address are in the ranges 8000h through 9C00h
   and C000h through EC00h, in increments of 400h. The addresses for
   pages 0 through 3 must be contiguous in order to maintain
   compatibility with version 3.2 of the Lotus/Intel/Microsoft
   Expanded Memory Specification (LIM EMS). If you use the Mx switch,
   the FRAME switch, or the /Pmmmm switch, you cannot specify the
   addresses for pages 0 through 3 for the /Pmmmm switch.

   Prevents EMM386 from using a particular range of segment addresses
   for an EMS page or for UMBs. Valid values for mmmm and nnnn are in
   the range A000h through FFFFh and are rounded down to the nearest
   4-kilobyte boundary. The X switch takes precedence over the I
   switch if the two ranges overlap.

   Specifies a range of segment addresses to be used (included) for an
   EMS page or for UMBs. Valid values for mmmm and nnnn are in the
   range A000h through FFFFh and are rounded down to the nearest 4-
   kilobyte boundary. The X switch takes precedence over the I switch
   if the two ranges overlap.

   Specifies the lowest segment address available for EMS "banking"
   (swapping of 16KB pages). Valid values are in the range 1000h
   through 4000h. The default value is 4000h.

   Ensures that the specified amount (in kilobytes) of extended memory
   will still be available after EMM386 is loaded. The default value
   is 0.

   Specifies how many fast alternate register sets (used for
   multitasking) you want to allocate to EMM386. Valid values are in
   the range 0 through 254. The default value is 7. Every alternate
   register set adds about 200 bytes to the size in memory of EMM386.

   Specifies how many handles EMM386 can use. Valid values are in the
   range 2 through 255. The default value is 64.

   Specifies how many kilobytes of memory should be reserved for
   buffered direct memory access (DMA). Discounting floppy disk DMA,
   this value should reflect the largest DMA transfer that will occur
   while EMM386 is active. Valid values for nnn are in the range 16
   through 256. The default value is 32.

   Specifies a range of segment addresses to be used for UMBs and also
   enables EMS support. If you do not specify a range, EMM386 uses all
   available adapter space to create UMBs and a page frame for EMS.

   Provides access to the upper memory area but prevents access to
   expanded memory.

   Disables support for VCPI programs. This switch must be used with
   the NOEMS switch. If you specify the NOVCPI switch without
   specifying the NOEMS switch, EMM386 does not disable VCPI support.
   If you specify both switches, EMM386 disregards the MEMORY
   parameter and the MIN switch. Disabling support for VCPI programs
   reduces the amount of extended memory allocated.

   Specifies that EMM386 use an additional check to determine the
   availablity of upper memory for use as UMBs or EMS windows. On some
   computers, specifying this switch may have no effect or cause
   EMM386 to identify upper memory areas as available when they are
   not. As a result, your computer might stop responding.

   Directs EMM386 to display status and error messages while loading.
   By default, EMM386 displays messages only if it encounters an error
   condition. You can abbreviate VERBOSE as V. (To display status
   messages without adding the VERBOSE switch, press and hold down the
   ALT key while EMM386 starts and loads.)

   Reserves a specified range of segment addresses for Windows instead
   of for EMM386. Valid values for mmmm and nnnn are in the range
   A000h through FFFFh and are rounded down to the nearest 4-kilobyte
   boundary. The X switch takes precedence over the WIN switch if the
   two ranges overlap. The WIN switch takes precedence over the RAM,
   ROM, and I switches if their ranges overlap.

   Prevents EMM386 from loading into the upper memory area. Normally,
   a portion of EMM386 is loaded into upper memory. Specifying this
   switch decreases available conventional memory and increases the
   upper memory area available for UMBs.

   Specifies a range of segment addresses that EMM386 uses for shadow
   RAM--random-access memory used for read-only memory (ROM). Valid
   values for mmmm and nnnn are in the range A000h through FFFFh and
   are rounded down to the nearest 4-kilobyte boundary. Specifying
   this switch may speed up your system if it does not already have
   shadow RAM.

   Prevents EMM386 from moving the extended BIOS data from
   conventional memory to upper memory.

   Specifies that EMM386 use an alternate handler to restart your
   computer when you press CTRL+ALT+DEL. Use this switch only if your
   computer stops responding or exhibits other unusual behavior when
   EMM386 is loaded and you press CTRL+ALT+DEL.

   When EMM386 is configured to provide upper memory blocks (by using
   the NOEMS or RAM switches), EMM386 will also automatically backfill
   conventional memory if there is less than 640k, in order to bring
   total conventional memory up to 640k.  However, because Windows
   does not support backfilled conventional memory, use the NOBACKFILL
   switch if your computer has less than 640K of conventional memory.

HIMEM.SYS

HIMEM is an extended-memory manager--a program that coordinates the use of your computer's extended memory, including the high memory area (HMA), so that no two programs or device drivers use the same memory at the same time.

You install HIMEM by adding a DEVICE command for HIMEM.SYS to your CONFIG.SYS file. The HIMEM.SYS command line must come before any commands that start programs or device drivers that use extended memory; for example, the HIMEM.SYS command line must come before the EMM386.EXE command line.

Syntax

DEVICE=[drive:][path]HIMEM.SYS [/A20CONTROL:ON|OFF] [/CPUCLOCK:ON|OFF][/EISA] [/HMAMIN=m] [/INT15=xxxx] [/MACHINE:xxxx] [/NOABOVE16] [/NOEISA][/NUMHANDLES=n] [/SHADOWRAM:ON|OFF] [/TESTMEM:ON|OFF] [/VERBOSE] [/X]

In most cases, you won't need to specify command-line options. The default values for HIMEM.SYS are designed to work with most hardware.

Parameter

[drive:][path]

   Specifies the location of the HIMEM.SYS file. HIMEM.SYS should
   always be located on the same drive that contains your MS-DOS
   files. If the HIMEM.SYS file is in the root directory of your
   startup drive, you don't need to include a path. However, you must
   always include the complete filename (HIMEM.SYS).

/A20CONTROL:ON|OFF

   Specifies whether HIMEM is to take control of the A20 line even if
   A20 was on when HIMEM was loaded. The A20 handler gives your
   computer access to the HMA. If you specify /A20CONTROL:OFF, HIMEM
   takes control of the A20 line only if A20 was off when HIMEM was
   loaded. The default setting is /A20CONTROL:ON.

   Specifies whether HIMEM is to affect the clock speed of your
   computer. If your computer's clock speed changes when you install
   HIMEM, specifying /CPUCLOCK:ON may correct the problem; however,
   enabling this option slows down HIMEM. The default setting is
   /CPUCLOCK:OFF.

   Specifies that HIMEM should allocate all available extended memory.
   This switch is necessary only on an EISA (Extended Industry
   Standard Architecture) computer with more than 16 MB of memory; on
   other computers, HIMEM automatically allocates all available
   extended memory.

   Specifies how many kilobytes of memory a program must require for
   HIMEM to give that program use of the HMA. Only one program can
   use the HMA at a time; HIMEM allocates the HMA to the first program
   that meets the memory-use requirements set by this option. You can
   specify a value from 0 to 63.

   Set /HMAMIN to the amount of memory required by the program that
   uses the most HMA memory.

   The /HMAMIN option is not required; the default value is zero.
   Omitting this option (or setting it to zero) specifies that HIMEM
   allocate the HMA to the first program that requests it, regardless
   of how much of the HMA the program is going to use.

   The /HMAMIN option has no effect when Windows is running in 386
   Enhanced mode.

   Allocates the amount of extended memory (in kilobytes) to be
   reserved for the Interrupt 15h interface. Some older programs use
   the Interrupt 15h interface to allocate extended memory rather than
   using the XMS (eXtended-Memory Specification) method provided by
   HIMEM. If you use these programs, you can ensure enough memory is
   available to them by setting xxxx to 64 KB larger than the amount
   required by the program.

   You can specify a value from 64 to 65535; however, you cannot
   specify more memory than your system has available. If you specify
   a value less than 64, the value becomes 0. The default value is 0.

   Specifies what type of computer you are using. Usually, HIMEM can
   detect your computer type successfully; however, there are a few
   computers that HIMEM cannot detect. On such systems, HIMEM uses the
   default system type (IBM AT or compatible). You might need to
   include the /MACHINE option if your computer is a type that HIMEM
   cannot detect and if HIMEM does not work properly on your system by
   using the default system type.

   Currently, systems that require this option include Acer 1100,
   Wyse, and IBM 7552.

   The value for xxxx can be any of the codes or their equivalent
   numbers listed in the following table.

Code         Number  Computer type

at           1       IBM AT or 100% compatible

ps2          2       IBM PS/2

ptlcascade   3       Phoenix Cascade BIOS

hpvectra     4       HP Vectra (A & A+)

att6300plus  5       AT&T 6300 Plus

acer1100     6       Acer 1100

toshiba      7       Toshiba 1600 & 1200XE

wyse         8       Wyse 12.5 Mhz 286

tulip        9       Tulip SX

zenith       10      Zenith ZBIOS

at1          11      IBM PC/AT (alternative delay)

at2          12      IBM PC/AT (alternative delay)

css          12      CSS Labs

at3          13      IBM PC/AT (alternative delay)

philips      13      Philips

fasthp       14      HP Vectra

ibm7552      15      IBM 7552 Industrial Computer

bullmicral   16      Bull Micral 60

dell         17      Dell XBIOS

   Specifies not to use INT 15h (ax==E801h) Compaq Bigmem support to
   scan for extended memory.

   Specifies that HIMEM should not do EISA scanning for extended
   memory.

   Specifies the maximum number of extended-memory block (EMB) handles
   that can be used simultaneously. You can specify a value from 1 to
   128; the default value is 32. Each additional handle requires an
   additional 6 bytes of memory.

   The /NUMHANDLES option has no effect when Windows is running in 386
   Enhanced mode.

   Specifies whether to disable shadow RAM (SHADOWRAM:OFF) or to leave
   the ROM code running from RAM (SHADOWRAM:ON).

   Some computers make ROM code run faster by "shadowing" it in RAM--
   that is, by copying the ROM code into faster RAM memory at startup,
   which uses some extended memory. On computers that use shadow RAM
   and have less than 2 MB of RAM, HIMEM usually attempts to disable
   shadow RAM to recover additional extended memory for Windows to
   use. (HIMEM can disable shadow RAM only on certain types of
   systems.) When HIMEM disables shadow RAM, the ROM code runs in the
   slower ROM instead of RAM; therefore, your computer might run
   slightly slower than it did before.

   Determines whether HIMEM performs a memory test when your computer
   starts. By default, HIMEM tests the reliability of your computer's
   extended memory each time your computer starts. This test can
   identify memory that is no longer reliable; unreliable memory can
   cause system instability or loss of data. HIMEM's memory test is
   more thorough than the standard power-up memory test performed by
   most computers. To prevent HIMEM from performing the memory test,
   specify /TESTMEM:OFF. Disabling the memory test will shorten the
   startup process. (The default setting is /TESTMEM:ON.)

   Directs HIMEM to display status and error messages while loading.
   By default, HIMEM does not display any messages unless it
   encounters an error. You can abbreviate /VERBOSE as /V. (To display
   status messages without adding the /VERBOSE switch, press and hold
   the ALT key while HIMEM starts and loads.)

   Specifies not to use INT 15h (ax==E820h), the latest extended
   memory support API.

RAMDRIVE.SYS

Uses part of your computer's random-access memory (RAM) to simulate a hard disk drive. This device driver must be loaded by a DEVICE or DEVICEHIGH command in your CONFIG.SYS file.

RAM drives are much faster than hard disk drives because your computer can read information faster from memory than from a hard disk. A RAM drive appears to be a normal hard disk drive; you can use it just as you would any hard disk drive. The most important difference between a real disk drive and a RAM drive is that because it exists only in memory, information on a RAM drive is lost when you turn off or restart your computer. You can set up as many RAM drives as you want, up to the amount of memory your computer has. To do this, add one RAMDRIVE.SYS line to your CONFIG.SYS file for each additional RAM drive you want.

Syntax

 DEVICE=[drive:][path]RAMDRIVE.SYS [DiskSize SectorSize [NumEntries]]]
 [/E | /A]

[drive:][path]

   Specifies the location of the RAMDRIVE.SYS file.

   Specifies how many kilobytes of memory you want to use for the RAM
   drive. For example, to create a 640K RAM drive, specify 640. If you
   don't specify an amount, RAMDrive will create a 64K RAM drive. You
   can specify a value from 4 to 32767. However, you cannot specify
   more memory than your system has available.

   Specifies the disk sector size in bytes. The size can be 128, 256,
   or 512 bytes. (If you include a SectorSize value, you must also
   include a value for DiskSize.)

   Generally, you should use the default sector size of 512 bytes.

   Limits the number of files and directories you can create in the
   RAM drive's root directory. The limit can be from 2 to 1024
   entries; the limit you specify is rounded up to the nearest sector
   size boundary. If you do not specify a limit, you can create up to
   64 entries in the RAM drive's root directory. (If you include a
   value for NumEntries, you must also include values for DiskSize and
   SectorSize.)

   If there is not enough memory to create the RAM drive as specified,
   RAMDrive will try to create it with a limit of 16 directory
   entries.
   This may result in a RAM drive with a different limit from the one
   you specified.

/E

   Creates the RAM drive in extended memory.

   For RAMDrive to use extended memory, your system must be configured
   so that it provides extended memory, and a DEVICE command for the
   extended-memory manager (such as HIMEM.SYS) must appear in your
   CONFIG.SYS file before the DEVICE command for RAMDRIVE.SYS. In
   general, it is best to create a RAM drive in extended memory if
   your system has extended memory.

   Creates the RAM drive in expanded memory.

   For RAMDrive to use expanded memory, your system must be configured
   so that it provides expanded memory, and the DEVICE command for the
   expanded-memory manager (such as EMM386, 386MAX, CEMM, or QEMM)
   must appear in your CONFIG.SYS file before DEVICE command for
   RAMDRIVE.SYS.

SETVER.EXE

SETVER.EXE loads into memory the MS-DOS version table, which lists names of programs and the number of the MS-DOS version with which each program is designed to run.

Syntax

    DEVICE=[drive:][path]SETVER.EXE

[drive:][path]

   Specifies the location of the SETVER.EXE file.