Garmin GPSMAP 188C Owner's Manual page 79

When transferring data between two Garmin
units, always set one to Host and use the other
unit to either Send or Request the data.
To select an input/output format:
1. Select Port 1 or Port 2, highlight the Serial Data Format
field, and press ENTER.
2. Use the ROCKER to select a setting, and press ENTER.
GPSMAP 188/188C Sounder Owner's Manual
To select a transfer mode:
1. Use the ROCKER to select Garmin Data Transfer in the
Serial Data Format field.
2. Highlight the Transfer Mode field, and press ENTER.
3. Use the ROCKER to select a setting, and press ENTER.
Advanced NMEA settings to adjust the NMEA output are available
if you have one of the ports set to NMEA In/NMEA. Advanced
NMEA settings enable/disable certain sentences and adjust the
number of Lat/Lon output precision digits. Settings affect both Port
1 and Port 2 NMEA outputs.
M M > C T
AIN ENU OMM AB
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