4 HP BIOS

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.

The procedure for updating the System ROM firmware is described on page 50.

System Memory Map

Reserved memory used by accessory boards must be located in the area from C8000h to EFFFFh.

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

128 KB BIOS (Flash/Shadow)1

 

 

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)

 

 

FFFE 0000 - FFFF FFFF

128 KB BIOS (Flash)

 

 

 

1.This is for Physical memory. As soon as the PST has been completed, the E000-EFFF area has to be released for UMBs.

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