Small Footprint RMII 10/100 Ethernet Transceiver with HP Auto-MDIX Support
Datasheet
Table 5.39 MODE[2:0] Bus
DEFAULT REGISTER BIT VALUES
MODE[2:0]
MODE DEFINITIONS
REGISTER 0
[13,12,10,8]
REGISTER 4
[8,7,6,5]
000
001
010
10Base-T Half Duplex. Auto-negotiation disabled.
10Base-T Full Duplex. Auto-negotiation disabled.
0000
0001
1000
N/A
N/A
N/A
100Base-TX Half Duplex. Auto-negotiation
disabled.
CRS is active during Transmit & Receive.
011
100
100Base-TX Full Duplex. Auto-negotiation disabled.
CRS is active during Receive.
1001
1100
N/A
100Base-TX Half Duplex is advertised. Auto-
negotiation enabled.
CRS is active during Transmit & Receive.
0100
101
110
Repeater mode. Auto-negotiation enabled.
100Base-TX Half Duplex is advertised.
CRS is active during Receive.
1100
N/A
0100
N/A
Power Down mode. In this mode the transceiver will
wake-up in Power-Down mode. The transceiver
cannot be used when the MODE[2:0] bits are set to
this mode. To exit this mode, the MODE bits in
Register 18.7:5(see Table 5.30) must be configured
to some other value and a soft reset must be
issued.
111
All capable. Auto-negotiation enabled.
X10X
1111
The MODE[2:0] hardware configuration pins are multiplexed with other signals as shown in Table 5.40.
Table 5.40 Pin Names for Mode Bits
MODE BIT
PIN NAME
MODE[0]
MODE[1]
MODE[2]
RXD0/MODE0
RXD1/MODE1
CRS_DV/MODE2
Revision 1.0 (05-28-09)
SMSC LAN8720/LAN8720i
DATA5S4HEET
SMSC [ SMSC CORPORATION ]
