Navtex SNX - 300, Инструкция по эксплуатации

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CHAPTER 8. Supported interface sentences
8.1. IEC61097-6
C.1 NRX – NAVTEX received message
The NRX sentence is used to transfer the contents of a received NAVTEX message from the NAVTEX
receiver to another device. As the length of a single NAVTEX message may exceed the number of
characters permitted in a single NMEA 0183 sentence, many NRX sentences may be required to
transfer a single NAVTEX message.
$ - - N R X , x x x , x x x , x x , a a x x , x , h h m m s s . s s , x x , x x , x x x x , x . x , x . x , A , c - - c * h h < C R > < L F >
message body
7
status indication
6
total number of bad characters
total number of characters in this
series of NRX sentences
5
year
month 1-12
day 1-31
UTC of receipt of message
frequency table index 0-9
4
NAVTEX message code
3
sequential message id 00-99
2
sentence number 001-999
number of sentences 001-999
1
NOTE 1 The total number of sentences required to transfer the NAVTEX message from the NAVTEX radio receiver.
The first field specifies the total number of sentences used for a message, minimum value 1. The Sentence Number field
identifies the order of this sentence in the message, minimum value 1. All sentences contain the same number of fields. For
efficiency it is recommended that null fields be used in the additional sentences where the data is unchanged from the first
sentence (this applies to fields 4 through 12).
NOTE 2 The sequential message identifier provides a unique identifier for each NAVTEX message represented by a group of
sentences. Though the message code (field 4) contains a NAVTEX message serial number, there are special cases when the
message serial number is set to 00 and has a different meaning or when the same message code can occur more than once.
When these conditions occur, the sequential message identifier can be relied upon to uniquely identify this NAVTEX message
from other NAVTEX messages with the same message code.
NOTE 3 The NAVTEX message code contains three related entities. The first character identifies the transmitter coverage area
and the second character identifies the type of message. Both these characters are as defined in Table I of Recommendation
ITU-R M.625-3, combination numbers 1-26. Transmitter identification characters are allocated by the IMO NAVTEX Co-
ordinating Panel; these characters and the meanings of the message type characters are described in the NAVTEX manual (IMO
publication 951E). The remaining two characters are restricted to numerals with a range of 00 to 99 and represent a serial
number for each type of message. The value of 00 is a special case and not considered a serial number. See 4.3.5 for
interpretation of special case value of 00.
NOTE 4 The frequency indicator identifies the frequency that the NAVTEX message was received on:
0 = not received over air (eg test messages)
1 = 490 kHz
2 = 518 kHz
3 = 4209,5 kHz
4 through 9 are reserved for future use
NOTE 5 The total number of characters indicates the expected size of the message body sent in this sequence of NRX
sentences. It does not include the additional overhead for reserved characters found in table 1 of this IEC 61162-1.
NOTE 6 Status ‘A’ is used for syntactically correct message reception. Status ‘V’ is used for syntactically incorrect message
reception, e.g. end characters NNNN missing.
NOTE 7 The message body may contain reserved characters as defined in IEC 61162-1.