SMSC LAN9420i Manual De Usuario

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Single-Chip Ethernet Controller with HP Auto-MDIX Support and PCI Interface
Datasheet
SMSC LAN9420/LAN9420i
97
Revision 1.22 (09-25-08)
DATASHEET
4.2.9
Power Management Control Register (PMT_CTRL)
This register controls the wake event detection features. This register also controls the SCSR soft reset
to the PHY.
Note: If waking from a reduced-power state causes the assertion of a device reset, this register will
be cleared.
Offset:
00E0h
Size:
32 bits
BITS
DESCRIPTION
TYPE
DEFAULT
31:11
RESERVED
RO
-
10
PHY Reset (PHY_RST)
Writing a ‘1’ to this bit resets the PHY. The internal logic automatically holds 
the PHY reset for a minimum of 100us. When the PHY is released from 
reset, this bit is automatically cleared. All writes to this bit are ignored while 
this bit is high. 
SC
0b
9
Wake-On-Lan Wakeup Enable (WOL_EN)
When set, the MAC Wake Detect signal is enabled as a wake event and 
will set the PME_STATUS in the PCI_PMCSR. The MAC Wake Detect 
signal can be programmed for assertion upon detection of a Wakeup Frame 
or Magic Packet.
R/W
0b
8
Energy-Detect Wakeup Enable (ED_EN)
When set, the PHY Interrupt signal is enabled as a wake event and will set 
the PME_STATUS bit in the PCI_PMCSR. The PHY interrupt can be 
programmed for assertion upon detection of a link status change (Energy 
Detect) event.
R/W
0b
7:5
RESERVED
RO
-
4:3
Wakeup Status (WUPS)
This field indicates the cause of the last wake event. This field is cleared 
by writing ‘1’ to the currently set bit(s). WUPS is encoded as follows:
00b – No wakeup event detected
x1b – PHY interrupt (Energy-Detect)
1xb – MAC wakeup event (Wakeup Frame or Magic Packet) 
Note:
If waking from a reduced-power state causes the assertion of a 
device reset, the wakeup status bits will be cleared.
R/WC
00b
2:0
RESERVED
RO
000b