C-Nav 1000 R4, Installation Manual

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APPENDICES Page 52
APPENDIX A.4 – PROPRIETARY SENTENCES (PSTT)
In addition to standardized IEC sentences (described in IEC 61162-1) the
R4 Navigation System supports the following proprietary sentences on its
user ports.
Proprietary Output Sentence
The following proprietary sentence can be output from the R4 Navigation
System.
$PSTT,501 – RAIM Status
This sentence provides information on the current RAIM status, as well as
the settings used when calculating RAIM. It is output once every second.
$PSTT,501,hhmmss.ss,x,x.x,x.x,x.x
Field Format Name Type Comment
1 501 Sentence Id Unsigned
char 501 always
2 hhmmss.
ss
Time Char[9] Hours, minutes, seconds and milliseconds
in decimal notation.
(Field left empty if time not available)
3 x RAIM Flag Integer 0 = Good (Green)
1 = Caution (Yellow)
2 = Unsafe (Red)
4 x.x RAIM Radius Float RAIM Radius in meters.
5 x.x Prob. HPR Float Max allowed probability (in %) for that
the position is outside the RAIM Radius.
Fixed 5.0000.
6 x.x Prob. False Float Max allowed probability (in %) for that
the RAIM calculation is wrong.
Fixed 5.0000.
Proprietary Input Sentence
The following proprietary sentence can be input to the R4 Navigation
System.
$PSTT,510 – Set RAIM Accuracy Level
This sentence is received from an external device, typically an ECDIS
system, to change the RAIM accuracy level in the R4 Navigation System.
The setting received overrides any RAIM settings present in the active
route. When the active route has been ended, the override status is removed.
Routes sailed after this can modify the RAIM accuracy level.
$PSTT,510,x
Field Format Name Type Comment
1 510 Sentence Id Unsigned
char 510 always
2 x Navigation
Accuracy
Integer Navigation accuracy to set, in meters.
Valid values are 1 to 999.
If empty, the sentence removes any RAIM
override condition