Raymarine C120W, Installation Manual

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The NMEA 0183 standard carries similar information to SeaTalk.
However it has the important difference that one cable will only
carry information in one direction. For this reason NMEA 0183 is
generally used to connect a data receiver and a transmitter together,
e.g. a compass sensor transmitting heading to a radar display. This
information is passed in ‘sentences’, each of which has a three
letter sentence identifier. It is therefore important when checking
compatibility between items that the same sentence identifiers are
used some examples of which are:
• VTG - carries Course and Speed Over Ground data.
• GLL - carries latitude and longitude.
• DBT - carries water depth.
• MWV - carries relative wind angle and wind speed data.
NMEA baud rates
The NMEA 0183 standard operates at a number of different
speeds, depending upon the particular requirement or equipment
capabilities. Typical examples are:
• 4800 baud rate. Used for general purpose communications,
including FastHeading data.
• 9600 baud rate. Used for Navtex.
• 38400 baud rate. Used for AIS and other high speed applications.
2.4 Pack contents
Unpack the display unit carefully to prevent damage. Save the
carton and packing in case the unit has to be returned for service.
Planning the installation
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