82801BA Datasheet, PDF (77/498 Pages) Intel Corporation – Intel 82801BA I/O Controller Hub 2 (ICH2) and Intel 82801BAM I/O Controller Hub 2 Mobile

Functional Description
5.2.3.2
PCI Reset Signal
The PCIRST# signal may be activated in one of the following cases:
• During S3-S5 states
• Due to a CF9h reset
If PME# is enabled (in the PCI power management registers), PCIRST# assertion does not affect
any PME# related circuits (in other words, PCI power management registers and the wake-up
packet would not be affected). While PCIRST# is active, the LAN Controller ignores other PCI
signals. The configuration of the LAN Controller registers associated with ACPI wake events is not
affected by PCIRST#.
The integrated LAN Controller uses the PCIRST# or the PWROK signal as an indication to ignore
the PCI interface. Following the deassertion of PCIRST#, the LAN Controller PCI Configuration
Space, MAC configuration, and memory structure are initialized while preserving the PME# signal
and its context.
5.2.3.3
Wake-up Events
There are two types of wake-up events: “Interesting” Packets and Link Status Change. These two
events are detailed below.
Note:
If the WOL bit in the EEPROM is not set, wake-up events are supported only if the PME Enable bit
in the Power Management Control/Status Register (PMCSR) is set. However, if the WOL bit in the
EEPROM is set, and Wake on Magic Packet or Wake on Link Status Change are enabled, the
Power Management Enable bit is ignored with respect to these events. In the latter case, PME#
would be asserted by these events.
"Interesting" Packet Event
In the power-down state, the LAN Controller is capable of recognizing “interesting” packets. The
LAN Controller supports pre-defined and programmable packets that can be defined as any of the
following:
• ARP Packets (with Multiple IP addresses)
• Direct Packets (with or without type qualification)
• Magic Packet*
• Neighbor Discovery Multicast Address Packet (‘ARP’ in IPv6 environment)
• NetBIOS over TCP/IP (NBT) Query Packet (under IPv4)
• Internetwork Package Exchange* (IPX) Diagnostic Packet
This allows the LAN Controller to handle various packet types. In general, the LAN Controller
supports programmable filtering of any packet in the first 128 bytes.
82801BA ICH2 and 82801BAM ICH2-M Datasheet
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