Intel SE7520JR2 manual DOS Area, ISA Window Memory, Video or SMM Memory, Extended System Bios

Functional Architecture Intel® Server Board SE7520JR2

3.5.1.1.1DOS Area

The DOS region is 512 KB in the address range 0 to 07FFFFh. This region is fixed and all accesses go to main memory.

3.5.1.1.2ISA Window Memory

The ISA Window Memory is 128 KB between the address of 080000h to 09FFFFh. This area can be mapped to the PCI bus or main memory.

3.5.1.1.3Video or SMM Memory

The 128 KB Graphics Adapter Memory region at 0A0000h to 0BFFFFh is normally mapped to the VGA controller on the PCI bus. This region is also the default region for SMM space.

3.5.1.1.4Add-in Card BIOS and Buffer Area

The 128 KB region between addresses 0C0000h to 0DFFFFh is divided into eight segments of 16 KB segments mapped to ISA memory space, each with programmable attributes, for expansion cards buffers. Historically, the 32 KB region from 0C0000h to 0C7FFFh has contained the video BIOS location on the video card

3.5.1.1.5Extended System BIOS

This 64 KB region from 0E0000h to 0EFFFFh is divided into four blocks of 16 KB each, and may be mapped with programmable attributes to map to either main memory or to the PCI bus. Typically this area is used for RAM or ROM. This region can also be used extended SMM space.

3.5.1.1.6System BIOS

The 64 KB region from 0F0000h to 0FFFFFh is treated as a single block. By default, this area is normally read/write disabled with accesses forwarded to the PCI bus. Through manipulation of read/write attributes, this region can be shadowed into main memory.

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