82567 Datasheet, PDF (13/33 Pages) Intel Corporation – GbE Physical Layer Transceiver (PHY)

Datasheet—82567
Note:
3.2.3
3.2.4
possible. The Windows NDIS drivers (Windows XP and later), monitor the AC-to-DC
transition on the system to make the PHY negotiate to the lowest connection speed
supported by the link partner (usually 10 Mb) when the user unplugs the power cable
(switches from AC to DC power). When the AC cable is plugged in, the speed will
negotiate back to the fastest LAN speed. This feature can be enabled/disabled directly
from DMiX or through the Advanced Settings of the Window's driver.
When transferring packets at 1000/100 Mbps speed, if there is an AC-to-DC transition,
the speed will renegotiate to the lower speed. Any packet that was in process will be
retransmitted by the protocol layer. If the link partner is hard-set to only advertise a
certain speed, then the driver will negotiate to the advertised speed. Since the feature
is driver based, it is available in S0 state only.
Link Speed Battery Saver handles duplex mismatches/errors on link seamlessly by re-
initiating auto negotiation while changing speed. Link Speed Battery Saver also
supports Spanning Tree Protocol.
The packets would get re-transmitted for any protocol other than TCP as well.
System Idle Power Saver (SIPS)
System Idle Power Saver (SIPS) is a software-based power saving feature that is
enabled only with Microsoft* Windows* Vista*. This feature is only supported in the S0
state and can be enabled/disabled in the Advanced Tab of the Windows driver or
through DMiX. The power savings from this feature is dependent on the link speed of
the device. Please refer to Section 4.6 Tables 6-9 for the power dissipated in each link
state.
SIPS is designed to save power in mobile systems by negotiating to the lowest possible
link speed when both the network is idle and the monitor is turned off due to inactivity.
The SIPS feature is activated based on both of the following conditions.
• The Windows* Vista* NDIS driver receives notification from the Operating System
(OS) when the monitor is turned “OFF” due to non-activity.
• The LAN driver monitors the current network activity and determines that the
network is idle.
Then, with both the monitor “OFF” and the network idle, the LAN negotiates to the
lowest possible link speed supported by both the PHY and the link partner (typically 10
Mb). If the link partner is hard-set to only advertise a certain speed, then the LAN will
negotiate to the advertised speed. This link speed will be maintained until the LAN
driver receives notification from the OS that the monitor is turned “ON,” thus exiting
SIPS and re-negotiating to the highest possible link speed supported by both the PHY
and the link partner. If SIPS is exited when transferring packets, any packet that was
being transferred will be re-transmitted by the protocol layer after re-negotiation to the
higher link speed.
Low Power Link Up (LPLU)
Low Power Link Up is a firmware/hardware based feature that allows the designer to
make the PHY negotiate to the lowest connection speed first and then to the next
higher speed and so on. This setting allows users to save power when power is more
important than performance.
When speed negotiation starts, the PHY tries to negotiate for a 10 Mb/s link,
independent of speed advertisement. If link establishment fails, the PHY tries to
negotiate with different speeds. It enables all speeds up to the lowest speed supported
by the partner. For example, if the 82567 advertises 10 Mb/s only and the link partner
supports 1000/100 Mbps only , a 100Mbps link is established.
13