![](http://datasheet.mmic.net.cn/340000/82845MP_datasheet_16452463/82845MP_5.png)
Intel
82845MP/82845MZ Chipset-Mobile (MCH-M)
250687-002
Datasheet
5
R
3.8.17.
3.8.18.
3.8.19.
3.8.20.
3.8.21.
3.8.22.
3.8.23.
3.8.24.
MBASE1 – Memory Base Address Register – Device #1........................... 96
MLIMIT1 – Memory Limit Address Register – Device #1............................ 97
PMBASE1 – Prefetchable Memory Base Address Register – Device #1 ... 98
PMLIMIT1 – Prefetchable Memory Limit Address Register – Device #1.... 99
BCTRL1 – PCI-PCI Bridge Control Register – Device #1......................... 100
ERRCMD1 – Error Command Register – Device #1 ................................ 101
DWTMC – DRAM Write Thermal Management Control........................... 102
DRTMC – DRAM Read Thermal Management Control............................ 104
4.
System Address Map............................................................................................................... 105
4.1.
Memory Address Ranges............................................................................................ 105
4.1.1.
VGA and MDA Memory Space.................................................................. 106
4.1.2.
PAM Memory Spaces................................................................................ 107
4.1.3.
ISA Hole Memory Space........................................................................... 108
4.1.4.
TSEG SMM Memory Space...................................................................... 108
4.1.5.
System Bus Interrupt APIC Memory Space.............................................. 109
4.1.6.
High SMM Memory Space ........................................................................ 109
4.1.7.
AGP Aperture Space (Device #0 BAR)..................................................... 109
4.1.8.
AGP Memory and Prefetchable Memory................................................... 109
4.1.9.
Hub Interface A Subtractive Decode......................................................... 110
4.2.
AGP Memory Address Ranges ................................................................................... 110
4.2.1.
AGP DRAM Graphics Aperture................................................................. 110
4.3.
System Management Mode (SMM) Memory Range................................................... 111
4.3.1.
SMM Space Definition............................................................................... 111
4.3.2.
SMM Space Restrictions........................................................................... 112
4.4.
I/O Address Space ...................................................................................................... 112
4.5.
MCH-M Decode Rules and Cross-Bridge Address Mapping ...................................... 112
4.5.1.
Decode Rules for the Hub Interface A ...................................................... 112
4.5.2.
AGP Interface Decode Rules.................................................................... 113
5.
Functional Description.............................................................................................................. 114
5.1.
Host Interface Overview.............................................................................................. 114
5.1.1.
Dynamic Bus Inversion.............................................................................. 114
5.1.2.
System Bus Interrupt Delivery................................................................... 114
5.1.3.
Upstream Interrupt Messages................................................................... 115
5.2.
System Memory Interface ........................................................................................... 115
5.2.1.
DDR Interface Overview............................................................................ 115
5.2.2.
Memory Organization and Configuration................................................... 116
5.2.2.1.
Configuration Mechanism for SO-DIMMs..................................... 116
5.2.2.1.1.
Memory Detection and Initialization............................ 116
5.2.2.1.2.
SMBus Configuration and Access of the Serial
Presence Detect Ports................................................ 116
5.2.2.1.3.
Memory Register Programming ................................. 116
5.2.3.
DRAM Performance Description............................................................... 117
5.2.3.1.
Data Integrity (ECC) ..................................................................... 117
5.3.
AGP Interface Overview.............................................................................................. 117
5.3.1.
AGP Target Operations............................................................................. 118
5.3.2.
AGP Transaction Ordering........................................................................ 119
5.3.3.
AGP Signal Levels .................................................................................... 119
5.3.4.
4x AGP Protocol........................................................................................ 119
5.3.5.
Fast Writes................................................................................................ 119
5.3.6.
AGP FRAME# Transactions on AGP........................................................ 120