This is what the Raymarine autopilot says about NMEA connection.
Wire Colour   Pin   NMEA signal at s1000   Connection at 3rd Party GPS
         
Brown                    1   negative out                    NMEA --ve receive
Green                    2   positive out                    NMEA +ve receive
Orange                    3   positive in                    NMEA +ve transmit
Blue                    5   negative in                    NMEA --ve transmit
But the Humminbird NMEA connections read differently in the Humminbird manual:
The following NMEA sentences are output:
DPT - Depth
MTW - Water Temperature
GLL - Lat/Lon Position
GGA - GPS Fix Data
RMC - Recommended Minimum Specific GNSS Data
VTG - Course Over Ground and Ground Speed
ZDA - Time and Date
When navigating, the following NMEA sentences are also output:
APB - Autopilot Sentence B
BWR - Bearing and Distance to Waypoint
RMB - Recommended Minimum Navigation Info
Does this make sense to anyone?