GPSMAP 180 power/data connector (by 2 users)

Okay
guys: book says:
PIN 1 (red) 10-40 volts DC
PIN 2 (black) Ground
PIN 3 (blue) NMEA out Shows this goes to Autopilot/NMEA devise and to RXD positive RXD negative goes to ground (black)
PIN 4 (brown) NMEA in Goes to GBR 21 Beacon Receiver to a blue wire, brown wire on thaat devise goes to PIN 3 and the negative goes to ground
PIN 5 (white) no connection
PIN 6 (Green) no connection
PIN 7 (yellow) goes to alarm low Shows going to negative terminal on alarm relay and positive terminal goes to PIN 1 (red)

All Greek to me, have fun

Seadrive Joe