APPENDICES Page
63
Document id: 7000 108-011 A2
APPENDIX A.4 – PROPRIETARY OUTPUT SENTENCES (PSTT)
Additional to the standardised IEC sentences (described in IEC
61993-2) the R4MkII-AIS Transponder is able to output the
following proprietary sentences.
$PSTT,10A – UTC Date and Time
This sentence provides UTC Date and Time, i.e. R4MkII System
Time (based on internal GNSS time). It is output approximately
once every 10 seconds (
±
1 s).
$PSTT,XXX,YYYYMMDD,HHMMSS
Field Format
Name
Type
Range
1 10A
Sentence
Id
Unsigned
char
10A always
2
YYYYMMDD
Date
Char[8]
Year, month and day in decimal notation.
(00000000 = Not available)
3
HHMMSS
Time
Char[6]
Hour, minute and second in decimal
notation.
(999999 = Not available)
Example:
$PSTT,10A,19961028,135230*<FCS><CR><LF>
= Date
October 28, 1996
= Time 13:52:30 UTC
$PSTT,10C – Data Link Status
This sentence provides information about the traffic on the VHF
data link. It is output approximately once every 60 seconds. Traffic
load is calculated over the last frame (i.e. 60 seconds). Number of
units is derived from the internal user list and is generally the
number of received units within the last few minutes.
$PSTT,10C,C,S,LLL,NNNN
Field Format
Name
Type
Range
1 10C
Sentence
Id
Unsigned
char
10C always
2 C
Channel
Unsigned
char
A = VDL channel A
B = VDL channel B
3 LLL
Traffic
Load
Unsigned
short
Data link traffic load in percent, 0-100,
which equates to 0 to 100%.
4
NNNN
No of Units
Unsigned
short
No of units occupying the data link.
$PSTT,1F3 – Transponder Restart
This sentence will be output when the transponder has restarted.
$PSTT,1F3,R
Field Format
Name
Type
Range
1 1F3
Sentence
Id
Unsigned
char
1F3 always
2 R
Restart
Reason
Unsigned
char
0 = Unknown
1 = Cold Start
2 = General Protection Fault
3 = Power Fail
4 = Warm Start
