------------------------ MS-DOS v6.22 Help: DOS -------------------------
<Notes>                                                            <Index>


Specifies that MS-DOS should maintain a link to the upper memory area, load
part of itself into the high memory area (HMA), or both. You can use this
command only in your CONFIG.SYS file.





    Specifies whether MS-DOS should manage upper memory blocks (UMBs)
    created by a UMB provider such as EMM386.EXE. The UMB parameter
    specifies that MS-DOS should manage UMBs, if they exist. The NOUMB
    parameter specifies that MS-DOS should not manage UMBs. The default
    setting is NOUMB.

    Specifies whether MS-DOS should attempt to load a part of itself into
    the HMA (HIGH) or keep all of MS-DOS in conventional memory (LOW). The
    default setting is LOW.

Related Commands

For information about loading a device driver into the upper memory area,
see the <DEVICEHIGH> command.

For information about loading a program into the upper memory area, see the
<LOADHIGH> command.




Must install HIMEM.SYS for DOS=UMB or DOS=HIGH

You must install the HIMEM.SYS device driver or another extended memory
manager before you specify either DOS=UMB or DOS=HIGH.

Using the UMB parameter

You must specify the DOS=UMB command in order to load programs and device
drivers into the upper memory area. Using the upper memory area frees more
space in conventional memory for programs. In addition to using this
command, you must install an upper-memory-block (UMB) provider. If your
computer has an 80386 or 80486 processor, you can use <EMM386.EXE> for your
UMB provider.

If you specify DOS=UMB and no UMB provider is installed, MS-DOS will not
display an error message.

Using the HIGH parameter

If you specify the HIGH parameter, MS-DOS attempts to load part of itself
into the HMA. Loading part of MS-DOS into the HMA frees conventional memory
for programs. If you specify DOS=HIGH and MS-DOS is unable to use the HMA,
the following message will appear:

    HMA not available
    Loading DOS low

Combining parameters

You can include more than one parameter on a single DOS command line, using
commas to separate them. For example, the following command lines are



You can place the DOS command anywhere in your CONFIG.SYS file.


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Last update: December 07, 2002 14:45 by
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