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GETTING STARTED - INITIALIZATION AND I/O
Once all power and data connections have been made, the next step is to
turn the GlobalMap 2000 on. A message appears on the screen. Press the
CLR key to erase this message. If a Lowrance GPS module is connected,
then the mapping unit sends a “cold-start” message to the module. The
module will then start looking for the satellites. It can take up several
minutes for the module to determine your position. To speed up this
process, you can initialize the module by sending it your present position,
time, altitude, and date. See below for details on initializing the GPS
module.
If you have another manufacturers GPS or Loran-C receiver connected to
the GlobalMap 2000 through the NMEA cable, the mapping unit will show
the present position as soon as the receiver sends it. If you’re certain the
navigation receiver is sending position data, but the present position
display continues to flash for over 15 seconds, (signifying that it isn’t
receiving data) then check all wiring connections.
SAM modules start working at the same time the mapping unit is turned on.
The mapping unit also automatically sends both versions of NMEA 0183
data at power-on.
Initialization - GPS Module
Note: Read this section only if you have a GPS module connected to the
GlobalMap 2000. If you are using the NMEA 0183 input for position
information, skip this part.
In order for the GPS module to send position information, it must first find
the satellites. If you simply turn the unit on and wait, the unit will find them
by itself in 15 minutes or less. This is called “Cold Start.” If you let it find the
satellites, the time display will probably be wrong, since it will be showing
UTC time or the time at Greenwich, England. However, all other navigation
displays, including the position display will be correct. (You can set the time
to your local time.) To speed up the satellite acquisition process, you can
initialize the GPS module or “tell it where it is” the first time it’s turned on.
This initialization process is usually done only once and requires the
following data:
1. Your present position in latitude/longitude.
2. Your elevation above sea level (altitude).
3. Today’s date and time.
