82NM10 Datasheet, PDF (89/671 Pages) Intel Corporation – Intel® NM10 Family Express Chipset

Functional Description
5.3.1.6
When the LAN controller is in one of the low power states, it searches for a predefined
pattern in the first 128 bytes of the incoming packets. The only exception is the Magic
Packet, which is scanned for the entire frame. The LAN controller classifies the
incoming packets as one of the following categories:
• No Match: The LAN controller discards the packet and continues to process the
incoming packets.
• TCO Packet: The LAN controller implements perfect filtering of TCO packets. After
a TCO packet is processed, the LAN controller is ready for the next incoming
packet. TCO packets are treated as any other wake-up packet and may assert the
PME# signal if configured to do so.
• Wake-up Packet: The LAN controller is capable of recognizing and storing the first
128 bytes of a wake-up packet. If a wake-up packet is larger than 128 bytes, its
tail is discarded by the LAN controller. After the system is fully powered-up,
software has the ability to determine the cause of the wake-up event via the PMDR
and dump the stored data to the host memory.
Magic Packets are an exception. The Magic Packets may cause a power
management event and set an indication bit in the PMDR; however, it is not stored
by the LAN controller for use by the system when it is woken up.
Link Status Change Event
The LAN controller link status indication circuit is capable of issuing a PME on a link
status change from a valid link to an invalid link condition or vice versa. The LAN
controller reports a PME link status event in all power states. If the Wake on LAN bit in
the EEPROM is not set, the PME# signal is gated by the PME Enable bit in the PMCSR
and the CSMA Configure command.
Wake on LAN* (Preboot Wake-Up)
The LAN controller enters Wake on LAN mode after reset if the Wake on LAN bit in the
EEPROM is set. At this point, the LAN controller is in the D0u state. When the LAN
controller is in Wake on LAN mode:
• The LAN controller scans incoming packets for a Magic Packet and asserts the
PME# signal for 52 ms when a 1 is detected in Wake on LAN mode.
• The Activity LED changes its functionality to indicates that the received frame
passed Individual Address (IA) filtering or broadcast filtering.
• The PCI Configuration registers are accessible to the host.
The LAN controller switches from Wake on LAN mode to the D0a power state following
a setup of the Memory or I/O Base Address Registers in the PCI configuration space.
Datasheet
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