Datasheet
2013-2015 Microchip Technology Inc. DS00001987A-page 71
LAN8740A/LAN8740Ai
4.2.12 EDPD NLP/CROSSOVER TIME/EEE CONFIGURATION REGISTER
Index (In Decimal): 16 Size: 16 bits
Bits Description Type Default
15 EDPD TX NLP Enable
When in Energy Detect Power-Down (EDPD) mode (EDPWRDOWN =1), this
bit enables the transmission of single TX NLPs at the interval defined by the
EDPD TX NLP Interval Timer Select field.
0 = TX NLP disabled
1 = TX NLP enabled when in EDPD mode
R/W
NASR
0b
14:13 EDPD TX NLP Interval Timer Select
When in Energy Detect Power-Down (EDPD) mode (EDPWRDOWN = 1) and
EDPD TX NLP Enable is 1, this field defines the interval used to send single
TX NLPs.
00 = 1 second (default)
01 = 768 ms
10 = 512 ms
11 = 256 ms
R/W
NASR
00b
12 EDPD RX Single NLP Wake Enable
When in Energy Detect Power-Down (EDPD) mode (EDPWRDOWN =1), this
bit enables waking the PHY on reception of a single RX NLP.
0 = RX NLP wake disabled
1 = TX NLP wake enabled when in EDPD mode
R/W
NASR
0b
11:10 EDPD RX NLP Max Interval Detect Select
When in Energy Detect Power-Down (EDPD) mode (EDPWRDOWN = 1) and
EDPD RX Single NLP Wake Enable is 0, this field defines the maximum inter-
val for detecting two RX NLPs to wake from EDPD mode
00 = 64 ms (default)
01 = 256 ms
10 = 512 ms
11 = 1 second
R/W
NASR
00b
9:3 RESERVED RO -
2 PHY Energy Efficient Ethernet Enable (PHYEEEEN)
When set, enables Energy Efficient Ethernet (EEE) operation in the PHY.
When cleared, EEE operation is disabled.
Refer to Section 3.8.5, "Energy Efficient Ethernet" for additional information.
R/W
NASR
0b
1 EDPD Extend Crossover
When in Energy Detect Power-Down (EDPD) mode (EDPWRDOWN =1),
setting this bit to 1 extends the crossover time by 2976 ms.
0 = Crossover time extension disabled
1 = Crossover time extension enabled (2976 ms)
R/W
NASR
0b
0 Extend Manual 10/100 Auto-MDIX Crossover Time
When Auto-MIDX is enabled and the PHY is in manual 10BASE-T or
100BASE-TX mode, setting this bit to 1 extends the crossover time by 1984
ms to allow linking to an auto-negotiation link partner PHY.
0 = Crossover time extension disabled
1 = Crossover time extension enabled (1984 ms)
R/W
NASR
1b