Garmin GPS 100 Owner's Manual page 73

The Map Datum/Interface Page allows you to select the map datum and
output data format.
The GPS 100 calculates your position based on the WGS-84 map datum. If
your charts (or other electronic devices) are created using a different datum,
you must set the GPS 100 map datum for consistency (a position in the
WGS-84 datum could differ by 1000 feet or more from one calculated using
another datum). Check the datum in the legend of your chart and the
manuals of your other navigation equipment interfaced to the GPS 100.
To set the map datum...
· Move the cursor over the output format and press the CLR key to
select the desired map datum. You may select from AUSTRALIA,
EUROPE, GREAT BRITAIN, HAWAII, INDIA, IRELAND, NAD27
ALASKA, NAD27 CANADA, NAD27 USA, NAD83, NEW ZEALAND,
SOUTH AFRICA, SOUTH AMERICA, TOKYO, WGS72, and WGS84.
· Move the cursor over "OK?" and press the ENT key.
You may select the output data format of the GPS 100. "NMEA 0180",
"NMEA 0182" and "NMEA 0183" are available for interfacing with other
marine electronic devices. The "AVIATION" format is used in aviation
installations. You may select "DOWNLOAD" to download your stored
waypoints and routes from the GPS 100 to a personal computer. Finally, you
may turn the output "OFF" if you do not use the interface (see Section 14.1
for more information on NMEA interfaces).
To select the GPS 100 output format...
Output Format
MAP DATUM/INTERFACE PAGE
Map Datum
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