Garmin GPSMAP 178 Owner's Manual page 99

NMEA Interface
If you are going to interface the GPSMAP 178/178C with another piece of equipment (such as a radio
or autopilot), the unit needs to be set to output NMEA data. More information on wiring and NMEA data
may be found on page 96.
To activate the NMEA data:
1. On either port of the Comm Tab, highlight the 'Serial Data Format' field and press ENTER.
2. Select 'NMEA In/NMEA Out' and press ENTER.
Advanced NMEA Output Setup
The GPSMAP 178/178C NMEA data transmission can be customized to change the precision of the
Lat/Lon minutes, set up the waypoint IDs, and keep the output rate at two seconds. If the unit is set up
to output all of the available NMEA sentences, the output rate may exceed two seconds. The 'Advanced
NMEA Output Setup' Page allows you to turn on/off the GPS status (GSA. GSV), Waypoint/Route (WPL,
RTE), and the Garmin Proprietary sentences. See page 96 for more information on wiring and NMEA
data.
Lat/Lon Minutes Precision allows you to adjust the number of digits to the right of the decimal point
for transmission of NMEA Output, either 2, 3, or 4 digits. The Waypoint ID setting lets you choose to
output the waypoint identifiers as names or numbers.
To set up the Advanced NMEA page:
1. Highlight 'NMEA In/NMEA Out' in the Serial Data Format field, and press MENU. Select 'NMEA
Setup' and press ENTER.
2. To change the settings, place the highlight over the desired field and press ENTER. Make a
selection and press ENTER again to accept the selection.
Reference
Main Menu: Comm Tab
Activating NMEA data