This diagram illustrates two-way connections for both sending and receiving data. You can also use this diagram for one-way communication. The table below identifies the wiring harnesses and the NMEA^® 0183 wires.

To receive information from a NMEA 0183 device, refer to items , , , and when connecting the Garmin^® device.

To transmit information to a NMEA 0183 device, refer to items , , , and when connecting the Garmin device.

Item	Description
	Power source
	Power cable
	NMEA 0183 device
	NMEA 0183 cable

Item	Garmin Wire Function	Garmin Wire Color	NMEA 0183 Device Wire Function
	Power	Red	Power
	Power ground	Black	Power ground
	Rx/A (In +)	Purple	Tx/A (Out +)
	Rx/B (In -)	Gray	Tx/B (Out -)
	Tx/A (Out +)	Blue	Rx/A (In +)
	Tx/B (Out -)	Brown	Rx/B (In -)

If you are connecting to a hailer horn, see Connecting to a Hailer Horn or PA Speaker.

If you are connecting to an external speaker, see Connecting to an External Speaker). Speaker wires are the red and black wires on the data harness . The red power wire and black power ground wire are on the separate power harness .