Filter
Top Products
34
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
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.
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)