SMARC T335x Carrier Board Hardware Design Guide, Document Revision 1.2
2.2 Ethernet Interface
SMARC
hardware specification defines one
10/100/1000BaseT
Gigabit
Ethernet
LAN
port compliant with the IEEE 802.3ab standard and the other
optional one in the Alternate Function Block (AFB). The interface is backward
compatible with the
10/100Mbit
Ethernet (
10/100Base-TX
) standard.
The
LAN
interface of the
SMARC
module consists of 4 pairs of low voltage
differential pair signals designated from '
GBE_MDI0
' (+ and -) to '
GBE_MDI3
'
(+ and -) plus additional control signals for link activity indicators. These
signals can be used to connect a
10/100/1000BaseT
RJ45 connector with
integrated or external isolation magnetics to the carrier board.
SMARC T335X
module equips with two Fast Ethernet interfaces
(
10/100Base-TX
) that uses the
MDI0
as transmitting lanes and the
MDI1
as
receiving lane. The
MDI2
and
MDI3
lanes are not used and are left
unconnected. Develops could also implement
MDI2
and
MDI3
lanes if they
would like their carrier board to support
SMARC
modules that has Gigabit
Ethernet
LAN
. This will add some additional costs.