LEC-iMX8M User’s Guide
SGET SMARC Rev 2.1
Page 35
copyright © 2021 ADLINK Technology Inc.
4.3.8
LAN ports
4.3.8.1
First LAN port
The first LAN port is derived from the SOCs RGMII interface
Name
Pin #
Description
I/O
Type
I/O
Level
Power
Domain
PU /
PD
Comments
GB
GBE0_MDI0-
GB
GBE0_MDI1-
GB
GBE0_MDI2-
GB
GBE0_MDI3-
P30
P29
P27
P26
P24
P23
P20
P19
Gigabit Ethernet Controller 0: Media Dependent
Interface Differential Pairs 0, 1, 2, 3. The MDI can
operate in 1000, 100, and 10Mbit/sec modes. Some
pairs are unused in some modes according to the
following:
1000 100 10 _
MDI[0]+/- B1_DA+/- TX+/- TX+/-
MDI[1]+/- B1_DB+/- RX+/- RX+/-
MDI[2]+/- B1_DC+/-
MDI[3]+/- B1_DD+/-
GBE MDI
Runtime
Twisted pair signals for external
transformer.
GBE0_LINK100#
P21
Link Speed Indication LED for GBE 0 100Mbps
O OD
CMOS
3.3V
Runtime
Shall be able to sink 24mA or more Carrier
LED current
GBE0_LINK1000# P22
Link Speed Indication LED for GBE 0 1000Mbps
O OD
CMOS
3.3V
Runtime
Shall be able to sink 24mA or more Carrier
LED current
GBE0_LINK_ACT# P25
Link / Activity Indication LED Driven low on Link (10, 100
or 1000 mbps) Blinks on Activity
O OD
CMOS
3.3V
Runtime
Shall be able to sink 24mA or more Carrier
LED current
GBE0_CTREF
P28
Center-Tap reference voltage for Carrier board Ethernet
magnetic (if required by the Module GBE PHY)
Analog
0 to
3.3V max
Runtime
GBE0_SDP
P6
IEEE 1588 Trigger Signal. For hardware implementation
of PTP (precision time protocol)
IO
CMOS
3.3V
Runtime
