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GTN 650xi RS232 to Appareo (Altutude)

Acenels

Active Member
As the title suggests--has anyone been able to successfully connect a GTN 650 to an appareo for pressure altitude encoding vis RS-232?

Appareo has taken about 5 days per email to respond, and isn't exactly winning the customer support Olympics, so hoping someone here had figured this out (or can confirm it won't work).

I have the RS232 running through RS232 2 out on the GTN 650xi into pin 5 on the appareo. I have tried aviation 1 and 2 on the GTN, and each of the input selection options on the Appareo transponder to no avail.

I can't figure out which format works between the two, if any. My next step is to pull the harness apart and connect it directly to the G5 RS-232, and hope that will work if this won't, but thought I'd check in here first.
 
As the title suggests--has anyone been able to successfully connect a GTN 650 to an appareo for pressure altitude encoding vis RS-232?

.

This is confusing. The GTN is a gps, and does not itself know the pressure altitude, unless it is being fed in from some other source. The G5 does work because, as an EFIS, it contains a pressure sensing device, and can display indicated altitude and send out pressure altitude.
Do you have an EFIS? If so, you most likely (this is a guess!) want an RS232 OUT port set to something like format=FADC (Z format) or FADC w/ALT. A 327 transponder would be set (on the RS232-IN port) to format=FADC w/ALT. Everything at 9600 baud.
 
This is confusing. The GTN is a gps, and does not itself know the pressure altitude, unless it is being fed in from some other source. The G5 does work because, as an EFIS, it contains a pressure sensing device, and can display indicated altitude and send out pressure altitude.
Do you have an EFIS? If so, you most likely (this is a guess!) want an RS232 OUT port set to something like format=FADC (Z format) or FADC w/ALT. A 327 transponder would be set (on the RS232-IN port) to format=FADC w/ALT. Everything at 9600 baud.

That's right--EFIS, too. G5 can send it in the right format, I am less sure about G3X (ironically).

It is a fully integrated Garmin system (G3X and G5) with the exception of the Appareo. The GTN650 can take in the pressure altiture and push it via RS232, and should be reviving it via 429.

I think the problem is that the GTN 650 doesn't speak in the right format for the Appareo, but the G5 does. The aviation format coming out of the GTN deosn't seem to work with the Appareo--and I've tried a few. I think the right answer here is going to be plugin straight into the G5 since that is a confirmed config that works, and it doesn't seem like the RS232 route from the 650 wants to work (as it was originally wired).
 
In case anyone is searching for this in the future...

Although the GTN650 is taking Baro from the G3x, I never was able to get it to transmit to the Appareo via RS232.

I went straight to the Appareo from the G5 and it was easy-peasy via single dedicated line. The Appareo took the signal straight away, using the <25 foot coding.
 
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