Kongsberg Seatex AIS 100 Instruction Manual page 66

Seatex AIS 100 Instruction Manual, rev. 5
NOTE 1
NOTE 2
second AIS may be the same MMSI as the first AIS. This technique
can be used to request a third message from station-1.
BBM – Broadcast binary message
This sentence supports generation of an ITU-R M.1371 Binary
Broadcast Message (message 8) or Safety Related Broadcast Message
(message 14). It provides an external application with a means to
broadcast data, as defined by the application only – not the AIS. This
message offers great flexibility for implementing system functions
that use the AIS like a digital broadcast device. After receiving this
sentence, the AIS initiates a VHF broadcast of either message 8 or 14
within 4 s. (Also, see the ABK-sentence.)
The success or failure of the broadcast confirmed through the use of
the "Addressed and binary Broadcast Acknowledgement (ABK)"
sentence formatter, and the processes that support the generation of an
ABK-sentence. The AIS is limited in the amount of encapsulated data
that can be sent in each slot and frame. If the length of the message
would exceed five slots, or the AIS broadcast would exceed the limit
of 20 RATDMA slot transmissions for the current frame, the AIS will
return an ABK-sentence
The total number of IEC 61162-1 sentences needed to transfer the
contents of the binary message to the AIS. 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. All sentences contain the same number of fields.
Successive sentences may use null fields for fields that do not change
– such as fields 4 and 5.
The Sequential Message Identifier provides a message identification
number from 0 to 9 that is sequentially assigned as needed. Note that
this is only a sequential message identifier. This is used differently
than the "Message sequence identifier" of an ABM sentence. This
identifier is incremented for each new multi-sentence message. The
count resets to 0, after 9 is used. For the contents of a message 8 or 14
requiring multiple sentences, each sentence of the message contains
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External interfaces