Datasheet

LAN8720A/LAN8720AI
DS00002165B-page 48  2016 Microchip Technology Inc.
4.2.9 SPECIAL MODES REGISTER
Index (In Decimal): 18 Size: 16 bits
Bits Description Type Default
15 RESERVED RO —
14 RESERVED
Write as 1, ignore on read.
R/W
NASR
1b
13:8 RESERVED RO —
7:5 MODE
Transceiver mode of operation. Refer to Section 3.7.2, MODE[2:0]: Mode
Configuration for additional details.
R/W
NASR
Note 4-5
4:0 PHYAD
PHY Address. The PHY Address is used for the SMI address and for initial-
ization of the Cipher (Scrambler) key. Refer to Section 3.7.1, PHYAD[2:0]:
PHY Address Configuration for additional details.
R/W
NASR
Note 4-6
Note 4-4 The de
fault value of this field is determined by the MODE[2:0] configuration straps. Refer to
Section 3.7.2, MODE[2:0]: Mode Configuration for additional information.
Note 4-5 The de
fault value of this field is determined by the PHYAD[0] configuration strap. Refer to
Section 3.7.1, PHYAD[2:0]: PHY Address Configuration for additional information.
4.2.10 SYMBOL ERROR COUNTER REGISTER
Index (In Decimal): 26 Size: 16 bits
8:7 RESERVED RO —
6 ALTINT
Alternate Interrupt Mode:
0 = Primary interrupt system enabled (Default)
1 = Alternate interrupt system enabled
Refer to Section 3.6, Interrupt Management for additional information.
R/W 0b
5:2 RESERVED RO —
1 ENERGYON
Indicates whether energy is detected. This bit transitions to “0” if no valid
e
nergy is detected within 256ms. It is reset to “1” by a hardware reset and is
unaffected by a software reset. Refer to Section 3.8.3.2, Energy Detect
Power-Down for additional information.
RO 1b
0 RESERVED R/W 0b
Bits Description Type Default