Specification Sheet

Host Bridge/DRAM Registers

86 Datasheet, Volume 2 of 2

3.28 Legacy Access Control (LAC)—Offset 87h

This 8-bit register controls steering of MDA cycles and a fixed DRAM hole from 15-

16MB.

There can only be at most one MDA device in the system.

Access Method

Default: 0h

Type: CFG

(Size: 8 bits)

Offset: [B:0, D:0, F:0] + 87h

7 4 0

0 0 0 0 0 0 0 0

HEN

RSVD

MDAP60

MDAP12

MDAP11

MDAP10

Bit

Range

Default &

Access

Field Name (ID): Description

HEN: This field enables a memory hole in DRAM space. The DRAM that lies "behind"

this space is not remapped.

0: No memory hole.

1: Memory hole from 15MB to 16MB.

This bit is Intel TXT lockable.

6:4

Reserved (RSVD): Reserved.