Hi Rob, I have the 4500 EFIS and a 3400 EM and will be installing the certified NavWorx ADS600-BG. I have an Arinc 429 connected to the EFIS expansion connector for my AF-Pilot auto pilot. Your 4500 manual says I can connect the ADS600-B display to any available AFS serial port. The only serial port with no connection on my 4500 is the GPS Serial #1 RS-232 TXD. Would that work?

The manual also says the Altitude encoder port should connect to the AFS serial port #2. The only #2 serial port with no connection to it, is serial #2 GND.
On my 3400 EM their seems to be another expansion port that has nothing plugged into it. Can this be used?
Can't seem to find information on this 9 pin connector on the back of my 3400 EM.

All of my other serial ports are being used for SL-30, SL-40, Garmin 496, AFS Arinc-429, Garmin 327.

Don