Nexus 21 NX2 Server User Manual


 
SERVER
To double the transmission speed, select a NMEA sentence 2 times with 7 slots
apart, that is the slots should be as far away from each other as possible.
In a similar way, you can select the a sentence 4 times to make it 4 times faster.
Example: If you want to transmit the Nexus compass heading via NMEA, to for
example an autopilot, select (HDM) for every odd slot number, C79, C81, C83 ...
C93, that is 8 times which makes the speed 4 times / second. This leaves the
other 8 slots with even numbers, C78, C80, C82 ... C92 free to use for other
NMEA sentences.
For connection of NMEA instruments OUT from Server, (see 2.8).
2.10.3 Receive NMEA sentences IN to Server
There are 5 different main types of NMEA sentences:
1) Position related data: Position, SOG/COG, time, and a limited amount of
satellite status if a GPS is connected. The information is read if no other Nexus
GPS is connected.
2) Navigation data: (BTW), (DTW), (BOD), (XTE), (SET) and (DRIFT). This
information is read only if C75 NAV is set to (ON).
The Server will automatically send data to the Nexus Network. E.g.: (DRIFT),
(WCV), (TTG) and (CTS).
3) Compass heading is read only if (C76 CMP) is set to (ON). Heading is either
(HDT) (priority) or (HDM). Magnetic variation (from Nexus Network) is added to
(HDM) but not to (HDT).
4) Relative wind angle and wind speed is read from (VWR) data, only if (C77
WND) is set to (ON). True wind angle and wind speed is calculated by Nexus,
when the boat speed (the speed of the water) is known.
The following NMEA sentences can be received IN to Server:
APA Autopilot sentence ”A”
APB Autopilot sentence ”B”
BOD Bearing original destination
BWC Bearing and distance to waypoint
BWR Bearing and distance to waypoint (old)
DBT Depth measured from the transducers position
DPT Depth
GGA Global position fix data (GPS)
GLL Geographic position, Latitude/Longitude
GSA DOP and active satellites
GSV Satellites in view
HDM Heading, magnetic
HDT Heading, true
RMB Minimum navigation information
RMC Minimum specific GPS/transit data
RTE Not yet implemented
WCV Waypoint closure velocity
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