Connect Garmin Chart Plotter to Vesper AIS advice

[ColinR]

I want to connect my Garmin Echomap 50s chart plotter to Vesper Watchmate 850 AIS via NMEA 0183 but I’m struggling to understand the wiring instructions. Could anyone help please?
The AIS instructions show NMEA 0183 OUT (+) A 38400 baud and NMEA 0183 OUT (-) B going to Chart plotter NMEA IN (+) A and NMEA IN (-) B

The Chart plotter instructions show NMEA 0183 port1 Tx (out) (+)and NMEA 0183 port 1 Rx (out) (+).
In other words the AIS has two outs going to two ins, whereas the Garmin has an in and an out, both +. Not sure how to match these two up. Any help much appreciated!

 

[pvb]

The Vesper OUT (-) goes to the Garmin's 12v negative.

 

[ColinR]

Thank you. So the Vesper OUT (-) goes to Garmin ground (power and NMEA) and the Vesper OUT (+) goes to Garmin Rx in?

 

[pvb]

Thank you. So the Vesper OUT (-) goes to Garmin ground (power and NMEA) and the Vesper OUT (+) goes to Garmin Rx in?

Yes.

 

[ColinR]

Yes.

Thank you, that's really helpful.