Serial Data - Garmin GTN 725 Installation Manual

4.3.4

Serial Data

4.3.4.1 Serial Data Function
4.3.4.1.1 RS-232
The GTN is capable of interfacing with other aviation instruments by transmitting RS-232 Type 1 (often
known as ARNAV format) and Type 2 (often known as Northstar format) data on any RS-232 OUT port.
The data consists of the following (refer to Section B.1 for a detailed data format description):
Current latitude, longitude, and GPS altitude in feet (see Note below)
Current velocity vector (ground speed and direction of velocity vector over the ground)
Distance to waypoint
Cross track error
Desired track
Destination waypoint identifier
Bearing to destination waypoint
Magnetic variation
Navigation and warning status
Waypoint sequence in route
Waypoint position (latitude and longitude) and magnetic variation
Aviation RS-232 data may be transmitted with or without the current GPS altitude in feet.
Refer to Appendix B.
The GTN can receive pressure altitude, air data, and fuel data from certain systems on any RS-232 IN port.
If a GTN is installed with a 400W or 500W Series in an aircraft, any of the RS-232 ports on the GTN may
be cross-connected to RS-232 Port 3 on the GTN to manually transfer user-defined waypoints between
the two units.
Page 4-10
Rev. A
NOTE
GTN 725/750 TSO Installation Manual
190-01007-02