Lowrance HD LCX-110C Operation Instructions Manual page 41

The four wires for the com port are combined with the Power Supply
cable and NMEA 2000 Power cable to form the power/data cable (shown
earlier). Com-1 uses the yellow wire to transmit, the orange wire to
receive and the shield wire for signal ground. Your unit does not use
the blue wire.
Com-1
To unit
Com-1 wiring to receive NMEA position information
Com-1
To unit
Com-1 wiring to transmit NMEA position information
Orange (Receive)
Shield (Ground)
from some other GPS receiver.
Yellow (Transmit)
Shield (Ground)
to another NMEA-compatible device.
NMEA Transmit
Ground
NMEA Receive
Ground
33
To Other
GPS Receiver
To Other
Device