Sitex SP38 Autopilot, Installation And Operation Manual

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Sitex SP38 Installation and Operation
Document PN 29010101 V2r0
- 1 42 -
Data Used Sentence
Sentence
Priority
(larger number is
higher priority)
Magnetic heading *HDM 1
True heading *HDT 2
Magnetic heading,
Magnetic variation
*HDG 3
Range to waypoint *BWC 4
Vessel speed *VTG 5
Vessel speed *VHW 6
Vessel speed *VBW 7
Bearing origin to destination magnetic and true,
Waypoint ID
*BOD 8
Cross track error *XTE 9
Cross track error,
Arrival circle entered
Bearing origin to destination magnetic or true,
Waypoint ID
*APA 10
Course to steer magnetic and true *HSC 11
Cross track error,
Waypoint ID,
Range,
Bearing present to destination true,
Arrival circle entered
*RMB 12
Cross track error,
Arrival circle entered,
Bearing origin to destination magnetic or true,
Waypoint ID,
Bearing present to destination magnetic or true,
Course to steer magnetic or true
*APB 13
Vessel speed *RMA 14
Vessel speed,
Magnetic variation
*RMC 15
Latitude and longitude *GLL 16
Table 7 - NMEA Sentence Priority
NOTE: The Heading value used by the
SP38
may be in Degrees Magnetic or
True, depending on which sentences are received (assuming all sentences
have valid data):
•
If all of HDM, HDT and HDG are being received, or just HDT and HDG, or just HDM
and HDG, then the autopilot will use Magnetic Heading (indicated on the display by
an ‘M’ beside the Heading value – and will use the data value in the HDG sentence.
• If only HDM and HDT are received, or just HDT, then the autopilot will use True
Heading (indicated by a ‘T’), from the HDT sentence.
•
If only HDM is received, then the autopilot will use Magnetic Heading (indicated by an
‘M’), from that sentence.
Appendices