6 Technical Information

The PC’s Memory Map

The PC’s Memory Map

Memory Area

Memory Range

 

Hexadecimal

Used By

 

 

 

Address Range

 

 

 

 

 

 

Extended Memory: 1 MB to 4 MB

 

 

 

 

 

 

 

Extended memory

1024 KB upward

 

01000 to 0F0000

Windows Applications

 

 

 

 

 

Conventional Memory: 0 KB to 1024 KB (1 MB)

 

 

 

 

 

 

 

384 KB Reserved

960 KB to 1024 KB

 

0F0000 to 010000

64 KB BIOS area

Memory Area

 

 

 

 

896 KB to 960 KB

 

0E0000 to 0F0000

64 KB (available)

 

 

 

 

 

 

 

 

800 KB to 896 KB

 

0C8000 to 0E0000

96 KB available for

 

 

 

 

accessory boards

 

 

 

 

 

 

768 KB to 800 KB

 

0C0000 to 0C8000

32 KB Video BIOS Area

 

 

 

 

 

 

640 KB to 768 KB

 

0A0000 to 0C0000

128 KB Video Memory Area

 

 

 

 

 

640 KB Base

0 KB to 640 KB

 

09F000 to 0A0000

Extended BIOS Data Area

Memory Area

 

 

 

 

 

 

User Application Program

 

 

 

 

 

 

 

Area

 

 

 

 

 

 

 

 

MS-DOS Operating System

 

 

 

 

 

 

 

 

0500 to 0700

MS-DOS Temp Buffer

 

 

 

 

 

 

 

 

0400 to 04FF

BIOS Data Area

 

 

 

 

 

 

 

 

0000 to 03FF

Interrupt Vector Table

 

 

 

 

 

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