Product specifications

ProSavageDDR P4M266 – VT8751 P4 DDR SMA North Bridge

Revision 1.1, July 19, 2002 -20- Register Overview

We Connect

We ConnectWe Connect

We Connect

Technologies, Inc.

REGISTERS

The following tables summarize the configuration and I/O

registers of the P4M266. These tables also document the

power-on default value (“Default”) and access type (“Acc”)

for each register. Access type definitions used are RW

(Read/Write), RO (Read/Only), “—” for reserved / used

(essentially the same as RO), RWC (or just WC) (Read / Write

1’s to Clear individual bits), and W1 (Write Once then Read /

Only after that). Registers indicated as RW may have some

read/only bits that always read back a fixed value (usually 0 if

unused); registers designated as RWC or WC may have some

read-only or read write bits (see individual register

descriptions following these tables for details). All offset and

default values are shown in hexadecimal unless otherwise

indicated.

The graphics registers are described in a separate document.

Table 5. VT8751 / P4M266 Registers

P4M266 I/O Ports

Port # I/O Port Default Acc

22 PCI / AGP Arbiter Disable 00 RW

CFB-8 Configuration Address 0000 0000 RW

CFF-C Configuration Data 0000 0000 RW