Simrad ES60 - DATASHEET REV A, Руководство по установке

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Simrad ES60
NMEA
The
National Marine Electronics Association (NMEA)
has
de fi ned communication standards for maritime electronic
equipment, and the ES60 echo sounder conforms to these
standards. The most common standard is
NMEA 0183
, and the
National Marine Electronics Association describes it as follows:
• The NMEA 0183 Interface Standard de
fi nes electrical signal
requirements, data transmission protocol and time, and
speci fi c sentence formats for a 4800 baud serial data bus.
Each bus may have only one talker but many listeners.
For more information about the National Marine Electronics
Association and the NMEA 0183 standard, refer to the
organization’s web pages at www.nmea.org .
Telegrams
To move information between two electronic units, the data are
collected in
telegrams
. The content (protocol) of each telegram is
de fi ned by the NMEA standard, and several telegram types exist
to allow different type of data to be distributed.
The phrase
datagram
is also frequently used about this
communication method.
Unless you wish to write your own software, you do not need to
know how these telegrams are designed. However, whenever
you set up equipment interfaces, you need to ensure that each
system on your communication line is set up to send and receive
the same telegram. The standard allows one system to send data
(a “talker") and several others to receive data simultaneously
("listeners") on the same line. Therefore, you must ensure that
all products receiving data on a communication line is set up
to receive the same telegram(s) that the transmitting product
provides.
Standard NMEA 0183 communication
parameters
The communication parameters de fi ned for
NMEA 0183
are:
• 4800 bits per second
• 8 data bits
• no parity
• one stop bit
Some instruments will also offer other parameters and/or choices.
Ethernet interfaces
The following interfaces are set up to transmit and receive
information by means of ethernet lines.
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