4 BIOS overview

BIOS addresses

BIOS addresses

This section provides a summary of the main features of the HP system BIOS. This is software that provides an interface between the computer hardware and the operating system.

system memory map

0000

0000

- 0000 03FF

Real-mode IDT

 

 

 

 

0000

0400

- 0000 04FF

BIOS Data Area

 

 

 

 

0000

0500

- 0009 FC00

Used by OS

 

 

 

0009

FC00 - 0009 FFFF

Extended BIOS Data Area

 

 

000A_0000 - 000B_FFFF

Video RAM or

 

 

 

 

SMRAM (not visible unless in SMM)

 

 

 

 

000C

0000

- 000C 7FFF

Video ROM

 

 

 

 

000C

8000

- 000F FFFF

Adapter ROM, RAM, memory-mapped registers

 

 

 

000E 0000

- 000F FFFF

System BIOS (Flash/Shadow)

 

 

10 0000 - FF FFFF

Memory (1 MB to 16 MB)

 

 

 

100 0000

- 1FF FFFF

Memory (16 MB to 32 MB)

 

 

 

200 0000

-3FF FFFF

Memory (32 MB to 64 MB)

 

 

 

400 0000

-1FFF FFFF

Memory (64 MB to 512 MB)

 

 

FFF80000 - FFFF FFFF

512 KB BIOS (Flash)

 

 

 

 

 

hp I/O port map (I/O addresses used by the system)

Peripheral devices, accessory devices and system controllers are accessed via the system I/O space, which is not located in system memory space. The 64 KB of addressable I/O space comprises 8-bit and 16-bit registers (called

I/O ports) located in the various system components.

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