Datasheet
High-Performance 16-bit Non-PCI 10/100 Ethernet Controller with Variable Voltage I/O
Datasheet
SMSC LAN9221/LAN9221i 93 Revision 2.9 (03-01-12)
DATASHEET
5.3.13 PMT_CTRL— Power Management Control Register
This register controls the Power Management features. This register can be read while the
LAN9221/LAN9221i is in a power saving mode.
Note: The LAN9221/LAN9221i must always be read at least once after power-up, reset, or upon
return from a power-saving state or write operations will not function.
Offset: 84h Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:14 RESERVED RO -
13-12 Power Management Mode (PM_MODE)
– These bits set the
LAN9221/LAN9221i into the appropriate Power Management mode. Special
care must be taken when modifying these bits.
Encoding:
00b – D0 (normal operation)
01b – D1 (wake-up frame and magic packet detection are enabled)
10b – D2 (can perform energy detect)
11b – RESERVED - Do not set in this mode
Note: When the LAN9221/LAN9221i is in any of the reduced power
modes, a write of any data to the BYTE_TEST register will wake-
up the device. DO NOT PERFORM WRITES TO OTHER
ADDRRESSES while the READY bit in this register is cleared.
SC 00b
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 Enable (WOL_EN) – When set, the PME signal (if enabled
with PME_EN) will be asserted in accordance with the PME_IND bit upon a
WOL event. When set, the PME_INT will also be asserted upon a WOL
event, regardless of the setting of the PME_EN bit.
R/W 0b
8 Energy-Detect Enable (ED_EN) - When set, the PME signal (if enabled with
PME_EN) will be asserted in accordance with the PME_IND bit upon an
Energy-Detect event. When set, the PME_INT will also be asserted upon an
Energy Detect event, regardless of the setting of the PME_EN bit.
R/W 0b
7 RESERVED RO -
6 PME Buffer Type (PME_TYPE) – When cleared, enables PME to function
as an open-drain buffer for use in a Wired-Or configuration. When set, the
PME output is a Push-Pull driver. When configured as an open-drain output
the PME_POL field is ignored, and the output is always active low.
R/W
NASR
0b