Networking Silicon — 82551IT
The following tables list the functionality at the different power states for the 82551IT.
Table 11. Functionality at the Different Power States
Power State
Link
Functionality
•
•
Power-up state
PCI slave access
D0u
Don’t care
Full functionality at full power and wake on an
invalid link
Valid
D0a
D1
Full functionality at full power and wake on a valid
link
Invalid
•
•
Wake-up on “interesting” packets and link
invalid
Valid
PCI configuration access
•
•
Wake on link valid
Invalid
PCI configuration access
Valid
Same functionality as D1 (link valid)
Detection for valid link and no link integrity
Same functionality as D1 (link valid)
Detection for valid link and no link integrity
D2
Invalid
Valid
D3 (with power)
Invalid
Dx (x>0 without
PME#)
Don’t care
No wake-up functionality.
5.3.2
Wake-up Events
There are two types of wake-up events: “Interesting” Packets and Link Status Change. These two
events are detailed below.
Note: The wake-up event is supported only if the PME Enable bit in the Power Management Control/
Status (PMCSR) register is set.
5.3.2.1
“Interesting” Packet Event
In the power-down state, the 82551IT is capable of recognizing “interesting” packets. The 82551IT
supports pre-defined and programmable packets that can be defined as any of the following:
• Address Resolution Protocol (ARP) Packets (with Multiple IP addresses)
• Direct Packets (with or without type qualification)
• 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 82551IT to handle various packet types. In general, the 82551IT supports
programmable filtering of any packet in the first 128 bytes.
Datasheet
29
INTEL [ INTEL ]
