System Protocols - Raymarine a67 Wi-Fi Installation And Operation Instructions Manual

3.8 System protocols

Your Multifunction Display can connect to various instruments
and displays to share information and so improve the
functionality of the system. These connections may be made
using a number of different protocols. Fast and accurate data
collection and transfer is achieved by using a combination of the
following data protocols:
• SeaTalk hs
• SeaTalk ng
• NMEA 2000
• SeaTalk
• NMEA 0183
Note: You may find that your system does not use all of the
connection types or instrumentation described in this section.
SeaTalk hs
SeaTalk hs is an ethernet based marine network. This high speed
protocol allows compatible equipment to communicate rapidly
and share large amounts of data.
Information shared using the SeaTalk
• Shared cartography (between compatible displays).
• Digital radar data.
• Sonar data.
Seatalk ng
SeaTalk ng (Next Generation) is an enhanced protocol for
connection of compatible marine instruments and equipment. It
replaces the older SeaTalk and SeaTalk
SeaTalk ng utilizes a single backbone to which compatible
instruments connect using a spur. Data and power are carried
within the backbone. Devices that have a low draw can be
powered from the network, although high current equipment will
need to have a separate power connection.
SeaTalk ng is a proprietary extension to NMEA 2000 and the
proven CAN bus technology. Compatible NMEA 2000 and
SeaTalk / SeaTalk 2 devices can also be connected using the
appropriate interfaces or adaptor cables as required.
NMEA 2000
NMEA 2000 offers significant improvements over NMEA 0183,
most notably in speed and connectivity. Up to 50 units can
simultaneously transmit and receive on a single physical bus at
any one time, with each node being physically addressable. The
standard was specifically intended to allow for a whole network
of marine electronics from any manufacturer to communicate on
a common bus via standardized message types and formats.
SeaTalk
SeaTalk is a protocol which enables compatible instruments to
connect to each other and share data.
The SeaTalk cable system is used to connect compatible
instruments and equipment. The cable carries power and data
and enables connection without the need for a central processor.
Additional instruments and functions can be added to a SeaTalk
system, simply by plugging them into the network. SeaTalk
equipment can also communicate with other non-SeaTalk
equipment via the NMEA 0183 standard, provided a suitable
interface is used.
NMEA 0183
The NMEA 0183 Data Interface Standard was developed by
the National Marine Electronics Association of America. It is an
international standard to enable equipment from many different
manufacturers to be connected together and share information.
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
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hs network includes:
2 protocols.
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.
• 38400 baud rate. Used for AIS and other high speed
applications.
New a Series / New c Series / New e Series