Garmin GPSMAP 580 Owner's Manual page 61

After creating a New Directory Item, the name created is attached
to that particular MMSI number. If you return to the Log, the new
name appears under the corresponding MMSI number.
Another way to input a name is from the Entry Review page or the
DSC Distress Call or DSC Position Report pages. The name and
MMSI are sent to other Garmin GPS units. Only the MMSI numbers
are sent to other non-Garmin DSC users.
Making a Distress Call
To make a distress call, press the Mayday button on your VHF
radio. If you have DSC support, the call transmits on an emergency
channel with the MMSI number attached to the call. Any DSC-
equipped mariner (on sea or land) within range can receive the call.
GPSMAP 580/585 Owner's Manual
Setting Up DSC
Use the Setup sub tab to turn DSC on and off. If you have more than
one chartplotter and only want DSC to show on another chartplotter,
turn DSC off on this unit.
This Setup sub tab also allows you to simulate distress calls and
position reports while the unit is in Simulator mode. The Distress
Call simulator also helps to check if alarms are working properly.
DSC Setup
Main Menu
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