Datasheet
KSZ8081MNX/RNB
DS00002202C-page 36 2016-2018 Microchip Technology Inc.
0.15 Reset
1 = Software reset
0 = Normal operation
This bit is self-cleared after a ‘1’ is
written to it.
RW/SC
0
0.14 Loopback
1 = Loopback mode
0 = Normal operation
RW
0
0.13 Speed Select
1 = 100 Mbps
0 = 10 Mbps
This bit is ignored if auto-negotiation
is enabled (Register 0.12 = 1).
RW
Set by the SPEED strapping pin.
See the Strap-In Options –
KSZ8081MNX section for details.
0.12
Auto-
Negotiation
Enable
1 = Enable auto-negotiation process
0 = Disable auto-negotiation process
If enabled, the auto-negotiation
result overrides the settings in regis-
ters 0.13 and 0.8.
RW
Set by the NWAYEN strapping
pin.
See the Strap-In Options –
KSZ8081MNX section for details.
0.11 Power-Down
1 = Power-down mode
0 = Normal operation
If software reset (Register 0.15) is
used to exit power-down mode (Reg-
ister 0.11 = 1), two software reset
writes (Register 0.15 = 1) are
required. The first write clears
power-down mode; the second write
resets the chip and re-latches the pin
strapping pin values.
RW
0
0.10 Isolate
1 = Electrical isolation of PHY from
MII/RMII
0 = Normal operation
RW
Set by the ISO strapping pin.
See the Strap-In Options –
KSZ8081MNX section for details.
0.9
Restart Auto-
Negotiation
1 = Restart auto-negotiation process
0 = Normal operation.
This bit is self-cleared after a ‘1’ is
written to it.
RW/SC
0
0.8 Duplex Mode
1 = Full-duplex
0 = Half-duplex
RW
The inverse of the DUPLEX
strapping pin value.
See the Strap-In Options –
KSZ8081MNX section for details.
0.7 Collision Test
1 = Enable COL test
0 = Disable COL test
RW
0
0.6:0 Reserved Reserved
RO
000_0000
Register 1h – Basic Status
1.15 100BASE-T4
1 = T4 capable
0 = Not T4 capable
RO 0
1.14
100BASE-TX
Full-Duplex
1 = Capable of 100 Mbps full-duplex
0 = Not capable of 100 Mbps
full-duplex
RO 1
1.13
100BASE-TX
Half-Duplex
1 = Capable of 100 Mbps half-duplex
0 = Not capable of 100 Mbps
half-duplex
RO 1
1.12
10BASE-T
Full-Duplex
1 = Capable of 10 Mbps full-duplex
0 = Not capable of 10 Mbps full-
duplex
RO 1
TABLE 4-2: REGISTER DESCRIPTION (CONTINUED)
Address Name Description Mode Default