®
MII/RMII 10/100 Ethernet Transceiver with HP Auto-MDIX and flexPWR Technology in a Small Footprint
Datasheet
5.3.9.2
Mode Bus – MODE[2:0]
The MODE[2:0] bus controls the configuration of the 10/100 digital block. When the nRST pin is
deasserted, the register bit values are loaded according to the MODE[2:0] pins. The 10/100 digital
block is then configured by the register bit values. When a soft reset occurs (bit 0.15) as described in
Table 5.21, the configuration of the 10/100 digital block is controlled by the register bit values, and the
MODE[2:0] pins have no affect.
The LAN8710 mode may be configured using hardware configuration as summarized in Table 5.40.
The user may configure the transceiver mode by writing the SMI registers.
Table 5.40 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 5.41.
Table 5.41 Pin Names for Mode Bits
MODE BIT
PIN NAME
MODE[0]
MODE[1]
MODE[2]
RXD0/MODE0
RXD1/MODE1
COL/CRS_DV/MODE2
5.3.9.3
MII/RMII Mode Selection
MII or RMII mode selection is latched on the rising edge of the internal reset (nRESET) based on the
strapping of the RXD2/RMIISEL pin. The default mode is MII with the internal pull-down resistor. To
select RMII mode, pull the RXD2/RMIISEL pin high with an external resistor to VDDIO.
SMSC LAN8710/LAN8710i
Revision 1.0 (04-15-09)
DATA5S3HEET
SMSC [ SMSC CORPORATION ]
