GRT EX to TruTrak

Man, this stuff gets complicated as you add more and more!

I currently fly an RV-6. I have installed a GRT-EX and TruTrak Vizion. This setup works great. I have now ordered the GRT vertical autopilot software and the AINRC module. Before I dive under that panel AGAIN, I want to be sure I understand as much as possible about this wiring. The Vizion pinout shows an RS232 output on pin 7 labeled "output to G3X/AFS-5000 series" and says it is for "integrated control mode".

Does anyone know what this does, and does it have any application to my GRT?

I realize this is a little detailed, but thought I would throw it out anyway. Thanks.

Are you sure the Vizion pin in question says RS232-OUT (not IN?). To the best of my knowledge the GRT does not need nor accept data from the autopilot. But call GRT, they?re pretty receptive to this sort of question.
For sure, you need a pair of ARINC wires between the efis and TT, as well as an RS232 OUT from the efis to an IN at the TT.

Thanks Bob, I went ahead and posted this on the GRT forum. They are great about responding.