Datasheet

Micrel, Inc.
KSZ8081MNX/KSZ8081RNB
August
19, 2015 50
Revision 1.4
Register Description (Continued)
Address Name Description Mode
(10)
Default
Register 1Eh – PHY Control 1
1E.15:10 Reserved Reserved RO 0000_00
1E.9
Enable Pause
(Flow Control)
1 = Flow control capable
0 = No flow control capability
RO 0
1E.8 Link Status
1 = Link is up
0 = Link is down
RO 0
1E.7 Polarity Status
1 = Polarity is reversed
0 = Polarity is not reversed
RO
1E.6 Reserved Reserved RO 0
1E.5
MDI/MDI-X
State
1 = MDI-X
0 = MDI
RO
1E.4 Energy Detect
1 = Signal present on receive differential
pair
0 = No signal detected on receive differential
pair
RO 0
1E.3 PHY Isolate
1 = PHY in isolate mode
0 = PHY in normal operation
RW 0
1E.2:0
Operation
Mode
Indication
[000] = Still in auto-negotiation
[001] = 10Base-T half-duplex
[010] = 100Base-TX half-duplex
[011] = Reserved
[100] = Reserved
[101] = 10Base-T full-duplex
[110] = 100Base-TX full-duplex
[111] = Reserved
RO 000
Register 1Fh – PHY Control 2
1F.15 HP_MDIX
1 = HP Auto MDI/MDI-X mode
0 = Micrel Auto MDI/MDI-X mode
RW 1
1F.14
MDI/MDI-X
Select
When Auto MDI/MDI-X is disabled,
1 = MDI-X mode
Transmit on RXP,RXM (pins 5, 4) and
Receive on TXP,TXM (pins 7, 6)
0 = MDI mode
Transmit on TXP,TXM (pins 7, 6) and
Receive on RXP,RXM (pins 5, 4)
RW 0
1F.13
Pair Swap
Disable
1 = Disable Auto MDI/MDI-X
0 = Enable Auto MDI/MDI-X
RW 0
1F.12 Reserved Reserved RW 0