Datasheet

Datasheet 101

3.7.33 ATTBASE – Aperture Translation Table Base Register

(Device #0)

Address Offset: B8–BBh

Default Value: 00000000h

Access: Read/Write

Size: 32 bits

This register provides the starting address of the Graphics Aperture Translation Table Base

located in the main DDR SDRAM. This value is used by the GMCH/MCH’s Graphics Aperture

address translation logic (including the GTLB logic) to obtain the appropriate address translation

entry required during the translation of the aperture address into a corresponding physical DDR

SDRAM address. The ATTBASE register may be dynamically changed.

Note: The address provided via ATTBASE is 4 kB aligned.

Bit Description

31:12 This field contains a pointer to the base of the translation table used to map memory

space addresses in the aperture range to addresses in main memory.

11:0 Reserved