82562G Datasheet, PDF (22/44 Pages) Intel Corporation – Mbps Platform LAN Connect

82562G — Networking Silicon
5.4.1
Auto Plugging Detection
The 82562G senses the link all the time. If it detects loss of any link activity for more than 6.6
seconds, it indicates to the Media Access Controller (MAC) an “unplugged state” by resetting the
SQL LAN Connect control bit. If the 82562G is in reduced power mode and link activity is
detected, the 82562G notifies the MAC (in less than 1 second) that it is in a “plugged state” by
setting the SQL LAN Connect control bit. Link activity detection is based on energy detection.
5.4.2
Dynamic Reduced Power
The 82562G can be configured to support dynamic reduced power. In the dynamic reduced power
mode, the 82562G transitions to reduced power mode when an unplugged state is detected. The
82562G will only return to full power if the reduced power bit on the LAN Connect is reset and a
plugged state is detected. However, if the 82562G is not configured to support dynamic reduced
power, the 82562G operates according to the LAN Connect power-down bit (in other words, the
82562G operates in reduced power mode only if the LAN Connect power-down bit is set).
5.4.3
Configuration
The dynamic reduced power mode is configured through bit 13 of register 16. The default value is
disabled (0). The status of the 82562G can be read through bits 10:9 of register 16. When the
82562G is in reduced power mode, these two bits are set to 1b.
Table 5. Register 16 (10 Hexadecimal): PLC Status, Control and Address Data
Bit
13
Name
Dynamic Reduced Power Down
10
100BASE-TX Power Down
9
10BASE-T Power Down
Description
Read/Write
0 = Automatic reduced power down
enabled
1 = Automatic reduced power down
disabled (default)
Read/Write
The 100BASE-TX Power Down bit indicates
the power state.
0 = Normal operation (default)
1 = Power down
Read Only
The 10BASE-T Power Down bit indicates the
power state.
0 = Normal operation (default)
1 = Power down
Read Only
The 82562G PLC can enter a reduced power state manually through bit 11 of register 0. This bit is
ORed with the LAN Connect power down bit, which allows the 82562G to enter a reduced power
state.
Table 6. Register 0: Control Data
Bit
11
Name
Reduced Power Down
Description
Read/Write
0 = Reduced power down disabled (normal Read/Write
operation; default)
1 = Reduced power down enabled
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Datasheet