Garmin Apollo CNX80 Installation Manaul - page 73
Installation Procedures
GNS 480 (CNX80) Installation Manual
560-0982-01 Rev L
2-41
2.8.15.1
RMI / OBI Interface
P5-16 OBI
Clock
P5-17 OBI
Data
P5-37 OBI
Sync
The GNS 480 provides bearing from a waypoint for Bendix / King Serial OBI devices. The source used to
provide the bearing information is selected by the OBI Select input.
2.8.15.2
RMI / OBI Source Select
P5-36
OBI Select In
When the OBI Select input is open, the bearing data transmitted on the RMI / OBI output is bearing from
the currently active GPS waypoint. When the OBI Select input is grounded, the bearing data transmitted
on the RMI / OBI output is bearing from the currently tuned VOR station. If a localizer channel is tuned
on the GNS 480 NAV receiver, the bearing data is flagged as invalid.
2.8.16 DME Tuning
The GNS 480 can channel a DME based upon the tuned VOR frequency. The GNS 480 outputs the King
Serial DME channeling format. When the DME Select input is grounded, the GNS 480 will actively tune
the DME.
Refer to Appendix D for interconnect information.
2.8.16.1
Serial DME Tuning
P5-14
DME Clock Bus
P5-15
DME Data Bus
P5-35
DME Channel Req
When the DME Channel Request line is high, the GNS 480 provides serial DME channeling data on the
DME Clock / Data Buses. Data is provided in the King Serial DME channeling format.
2.8.16.2
DME Select In
P5-34
DME Select In
When grounded, the GNS 480 will acknowledge a DME channel request and output data on the DME
Serial Tuning interface. When open, the GNS 480 will not provide tuning information.