
Micrel, Inc.
KSZ8041NL/RNL
September 2010
38
M9999-090910-1.4
Register Description (Continued)
Address
Name
Description
Mode
(1)
Default
Register 1Eh – PHY Control 1
1e:15:14
LED mode
[00] =
LED1 : Speed
LED0 : Link/Activity
[01] =
LED1 : Activity
LED0 : Link
[10], [11] = Reserved
RW
00
1e.13
Polarity
0 = Polarity is not reversed
1 = Polarity is reversed
RO
1e.12
Reserved
RO
0
1e.11
MDI/MDI-X
State
0 = MDI
1 = MDI-X
RO
1e:10:8
Reserved
1e:7
Remote
loopback
0 = Normal mode
1 = Remote (analog) loop back is enable
RW
0
1e:6:0
Reserved
Register 1Fh – PHY Control 2
1f:15
HP_MDIX
0 = Micrel Auto MDI/MDI-X mode
1 = HP Auto MDI/MDI-X mode
RW
1
1f:14
MDI/MDI-X
Select
When Auto MDI/MDI-X is disabled,
0 = MDI Mode
Transmit on TX+/- (pins 7,6) and
Receive on RX+/- (pins 5,4)
1 = MDI-X Mode
Transmit on RX+/- (pins 5,4) and
Receive on TX+/- (pins 7,6)
RW
0
1f:13
Pairswap
Disable
1 = Disable auto MDI/MDI-X
0 = Enable auto MDI/MDI-X
RW
0
1f.12
Energy Detect
1 = Presence of signal on RX+/- analog wire
pair
0 = No signal detected on RX+/-
RO
0
1f.11
Force Link
1 = Force link pass
0 = Normal link operation
This bit bypasses the control logic and allow
transmitter to send pattern even if there is no
link.
RW
0