Second Garmin G3X - MAPMX required on both to GTN?

[bapboi]

After 10 years with a single G3X touch and GTN-650 I am adding a second G3X to the co-pilot side. I am unable to decipher if the second G3X also requires dedicated MAPMX wiring to the GTN-650 or if it will get what it needs from the other G3X. If it does require dedicated wiring should it share the RS-232 ports at the GTN with the other G3X or have it's own dedicated RS-232 ports at the GTN end? There are places in the wiring examples where it appears one connection may be enough (shown as connecting to "PFD or MFD") and I have also seen discussions that say the GTN is not capable of multiple RS-232 connections. Help!

Bruce
RV-7A (bought flying)
N3QW

 

[bjdecker]

Here's my connection cheat sheet...

 

[wjb]

After 10 years with a single G3X touch and GTN-650 I am adding a second G3X to the co-pilot side. I am unable to decipher if the second G3X also requires dedicated MAPMX wiring to the GTN-650 or if it will get what it needs from the other G3X. If it does require dedicated wiring should it share the RS-232 ports at the GTN with the other G3X or have it's own dedicated RS-232 ports at the GTN end? There are places in the wiring examples where it appears one connection may be enough (shown as connecting to "PFD or MFD") and I have also seen discussions that say the GTN is not capable of multiple RS-232 connections. Help!

Bruce
RV-7A (bought flying)
N3QW

Hi Bruce ... I have the MAPMX tied just to the PFD, and it shows up fine on both. I did need a separate receive-only feed for the G5, though

 

[mburch]

After 10 years with a single G3X touch and GTN-650 I am adding a second G3X to the co-pilot side. I am unable to decipher if the second G3X also requires dedicated MAPMX wiring to the GTN-650 or if it will get what it needs from the other G3X.

Nope, only one MapMX format RS-232 connection to a GDU 4xx required per GTN (or similar IFR GPS).

 

[bapboi]

Thanks everyone for sharing what you know! This will save me a few wires and a lot of brain cells.
This forum is an amazing resource...
Bruce

 

[supik]

Hi Bruce ... I have the MAPMX tied just to the PFD, and it shows up fine on both. I did need a separate receive-only feed for the G5, though

/off topic/

Bill, what software did you use for your schematics?

thx,