Garmin Apollo CNX80, Installation Manual

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Installation Procedures
2-32 560-0982-00 Rev D Apollo CNX80 Installation Manual
2.8.10 S
ERIAL
I
NTERFACES
2.8.10.1 RS232 / RS422
The CNX80 provides five bi-directional RS232 serial interfaces, two receive-only RS232 serial interfaces
and one bi-directional RS422 serial interface for making optional connections. The serial port can be used
for connecting to:
•
Resolvers, indicators, or electronic flight instruments that accept serial data
•
SL30 for Comm/NAV frequency transfers and DME distance from the database
•
MX20 to display VOR data on a map and database interface
•
A second CNX80
Serial interface specifications are included in Appendix B.
P1-4 RS232 RxD1 P5-1 RS232 RxD5
P1-5 RS232 TxD1 P5-21 RS232 TxD5
P1-23 Serial Ground 1 P5-41 Serial Ground 5
P1-21 RS232 RxD2 P5-2 RS232 RxD6
P1-22 RS232 TxD2 P5-22 RS232 TxD6
P1-3 Serial Ground 2 P5-42 Serial Ground 6
P1-7 RS232 RxD3 P5-10 RS232 RxD7
P1-6 RS232 TxD3 P5-30 RS232 RxD8
P1-25 Serial Ground 3 P5-44 Serial Ground 7/8
P1-11 RS422 RxD4 +
P1-26 RS422 RxD4 – P7-5 RESERVED DB30 TxD
P1-8 RS422 TxD4 + P7-3 Ground
P1-10 RS422 TxD4 –
NOTE
In order for a serial port to function correctly, the baud rate of the Rx and Tx channels on
a given RS232 or RS422 port must be the same. This must be considered when assigning
serial ports to interfacing equipment.
The CNX80 can communicate with an SL30 radio using RS232 RxD1 and TxD1. This interface allows
the SL30 to provide DME station information to the CNX80, which will provide the range to the DME
station back to the SL30 for display on its front panel.
The CNX80 can communicate with a PDA using the infrared sensor on the front bezel. If this feature is
used it must be set up on RxD3 and TxD3, not allowing these lines to be used for communication with
other devices.
The CNX80 can receive air data and fuel data from certain systems on RS232 RxD5, although it is
recommended that if a dedicated altitude encoder is used, it be connected to RS232 RxD8.
If two CNX80’s are installed in an aircraft, the RS232 RxD2 and TxD2 lines may be cross connected to
cross-fill flight plans and user-defined waypoints from one CNX80 to the other (this feature is not
implemented in the initial version of the CNX80). Altitude data and master/slave control is coordinated
between two CNX80’s.