System Address Map
R
162
Intel
®
82925X/82925XE MCH Datasheet
9.2
Main Memory Address Range (1 MB to TOLUD)
This address range extends from 1 MB to the top of physical memory that is permitted to be
accessible by the MCH (as programmed by BIOS). All accesses to addresses within this range
will be forwarded by the MCH to the main memory unless they fall into the optional TSEG or
optional ISA Hole.
The MCH provides a maximum main memory address decode space of 4 GB. The MCH does not
remap APIC or PCI Express memory space. This means that as the amount of physical memory
populated in the system reaches 4 GB, there will be physical memory that exists, yet non-
addressable; therefore, this memory is unusable by the system.
The MCH does not limit main memory address space in hardware.
Figure 9-3. Main Memory Address Range
Flash
0h
Contains
programmable
windows, ICH6/PCI
ranges.
TOLUD
Main_Mem_Addr
APIC
PCI Memory Range
0010_000h
(Optional)
TSEG (1 MB / 2 MB /
8 MB, optional)
Main Memory
ISA Hole (optional)
Main Memory
DOS Compatibility
Memory
00F0_000h
0100_000h
0 MB
1 MB
15 MB
16 MB
4 GB Maximum
FFFF_FFFFh
9.2.1
ISA Hole (15 MB–16 MB)
BIOS can create a hole at 15 MB–16 MB. Accesses within this hole are forwarded to the DMI.
The range of physical main memory disabled by opening the hole is not remapped to the top of
the memory; that physical main memory space is not accessible. This 15 MB–16 MB hole is an
optionally enabled ISA hole.
Содержание 82925X
Страница 78: ...Host Bridge DRAM Controller Registers D0 F0 R 78 Intel 82925X 82925XE MCH Datasheet...
Страница 98: ...EPBAR Registers Egress Port Register Summary R 98 Intel 82925X 82925XE MCH Datasheet...
Страница 108: ...DMIBAR Registers Direct Media Interface DMI RCRB R 108 Intel 82925X 82925XE MCH Datasheet...
Страница 156: ...Host PCI Express Graphics Bridge Registers D1 F0 R 156 Intel 82925X 82925XE MCH Datasheet...
Страница 172: ...System Address Map R 172 Intel 82925X 82925XE MCH Datasheet...
Страница 192: ...Electrical Characteristics R 192 Intel 82925X 82925XE MCH Datasheet...
Страница 220: ...Ballout and Package Information R 220 Intel 82925X 82925XE MCH Datasheet Figure 12 3 MCH Package Dimensions MCH...