Kongsberg Seatex AIS 100 Instruction Manual page 74

Seatex AIS 100 Instruction Manual, rev. 5
NOTE 5
NOTE 1
NOTE 2
requirements. The DTE indicator is only used as information provided
to the application layer – indicating that the transmitting station is
available for communications. On the transmitting side, the DTE
indicator may be set by an external application using this sentence.
DTE indicator flag values are:
0 = Keyboard and display are a standard configuration, and
communication is supported.
1 = Keyboard and display are either unknown or unable to support
communication (default setting).
The source identifier contains the "Talker ID" of the equipment at this
location. The AIS may use the "Talker ID" to identify multiple
sources of position data and to detect a change to the reference point
on the ship.
VDM – VHF Data-link Message
This sentence is used to transfer the entire contents of a received AIS
message packet, as defined in ITU-R M.1371 and as received on the
VHF Data Link (VDL), using the "6-bit" field type. The structure
provides for the transfer of long binary messages by using multiple
sentences.
The length of an ITU-R M.1371 message may be long and may
require the use of multiple sentences. The first field specifies the total
number of sentences used for a message, minimum value 1. The
second field identifies the order of this sentence in the message,
minimum value 1. These cannot be null fields.
The Sequential message identifier provides a message identification
number from 0 to 9 that is sequentially assigned and is incremented
for each new multi-sentence message. The count resets to 0 after 9 is
used. For a message requiring multiple sentences, each sentence of the
message contains the same sequential message identification number.
It is used to identify the sentences containing portions of the same
message. This allows for the possibility that other sentences might be
interleaved with the message sentences that, taken collectively,
contain a single message. This field shall be a null field when
messages fit into one sentence.
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External interfaces