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Upper Memory Area

: ,

Upper Memory Area (UMA), Upper Memory Blocks (UMB),   384 , 0000h (640 ) FFFFFh (1024 , 1 ). IBM PC.

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IBM IBM PC , -, (Memory-Mapped Input/Output). UMA A0000 (640 ) FFFFF (1 ).

, EGA- .

128 . :

  • A0000hBFFFFh  128 , , .
  • C0000hDFFFFh  128 , BIOS (Adapter ROM, Adapter RAM).
  • E0000hFFFFFh  128 , BIOS, ( 64 ).

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. , Intel 80386 , .

, (Upper Memory Block, UMB).

(, EMM386.EXE) .

MS-DOS, 5.0, UMB. HIMEM.SYS EMM386.EXE devicehigh loadhigh.

UMB, CONFIG.SYS :

device = HIMEM.SYS
device = EMM386.EXE
dos = UMB
devicehigh = ... ( UMB)

UMB. loadhigh.

, UMB, DOS 58xx.

, UMB.

, , . MS-DOS . UMA , , UMA , UMB. UMA , devicehigh loadhigh.

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. Upper . . High . Upper Memory Area / Upper Memory Block High Memory Area.

  UMB HMA, UMA .

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