Article: Q99008
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:6.0
Operating System(s):
Keyword(s):
Last Modified: 21-NOV-1999
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The information in this article applies to:
- Microsoft MS-DOS operating system version 6.0
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SUMMARY
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The MS-DOS 6 MEM command may display an incorrect value for Adapter RAM/ROM. On
many machines, MEM displays a table similar to the following:
Memory Type Total = Used + Free
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Conventional 640K 126K 515K
Upper 139K 111K 28K
Adapter RAM/ROM 384K 384K 0K
Extended (XMS) 7029K 2781K 4248K
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Total memory 8192K 3401K 4791K
It is not possible to have 384K Adapter RAM/ROM and a value greater than zero for
upper memory.
MORE INFORMATION
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Adapter RAM/ROM
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The value specified by Adapter RAM/ROM is calculated as follows:
1 MB (1024K) minus conventional memory, minus upper memory
block (UMB) space
Therefore, Adapter RAM/ROM is the sum of the following:
- Excluded UMB space
- Memory used by BIOS and adapter cards
- Expanded memory services (EMS) page frame(s)
However, on machines in which the amount of reported extended memory is below the
1 MB boundary (384K or less), MEM increases the value reported for Adapter
RAM/ROM so that the total memory on the system is a multiple of 1 MB.
NOTE: The amount of extended memory reported is correct.
Definitions
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The upper memory area (UMA) is a range of addresses between 640K and 1 MB
(1024K). This area is also commonly called the reserved address space.
Upper memory blocks (UMBs) are areas in the UMA that EMM386.EXE has reserved for
loading device drivers and terminate-and-stay-resident (TSR) programs high.
Additional query words: 6.00 XMS
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Keywords :
Technology : kbMSDOSSearch kbMSDOS600
Version : MS-DOS:6.0
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