Samyung SNX-300, Instruction Manual

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SNX-300
CHAPTER 9. IEC 61162 Message Composition
9.1. NRX & NRM
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.
$--NRX,xxx,xxx,xx,aaxx,x,hhmm ss.ss,xx,xx,xxxx,x.x,x.x,A,c--c*hh<CR><LF>
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