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Garmin 296 cable question - ports

LettersFromFlyoverCountry

Well Known Member
I'm hooking up the Garmin 296 to the electrical system -- done, got good power on it -- and making arrangements to get data out of it and into the TruTrak single-axis autopilot that I have. Stein (or more likely, Mike) made a pretty harness for it.

Anyway, there is a blue wire coming out of the Garmin which is Port 1 out. And there is a violet wire coming out of the Garmin, which is Port 2 out.

The question is: Is the data coming out of each port the same data? Or is there one particular wire (port) that needs to connect to the (in this case, blue) GPS wire on SteinAir's lovely TruTrak harness?

BTW, I'm running the Garmin harness into a(female) DSub connector
 
Use port 1 and you will be all set if you upgrade to a 396 or 496 in the future. Port 2 can and will work if you set the settings correctly. The 396 & 496 use port 2 for weather...

Each port has its own settings but there is an issue where some protocols are only able to be set on one port or the other at the same time and cannot be on both.
 
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Use port 1 and you will be all set if you upgrade to a 396 or 496 in the future. Port 2 can and will work if you set the settings correctly. The 396 & 496 use port 2 for weather...

Ah, OK, great. My plan is to upgrade to a 496 by the time the thing is flying (maybe next year).

How does the second port use the weather? Where would that data route to from the GPS? An EFIS?
 
The weather antenna sends its data to the GPS thru that port 2.

It is done internally and you have no control over that port 2 on a 396 or 496. Port 2 does not even show up on the port configuration tabs on those models.

The X96 series does not send weather data to anything only itself.

If you are starting with a 296 and plan to move to a 496, I highly recomend you use Port 1 or you will be rewiring later.
 
How does the second port use the weather?

As far as I can tell, on the 396/496, the com port 2 circuitry is only used internally for XM satellite data. It's not exposed through the external power/data harness, and it's not configurable on the user accessible system pages.

On the 296, it is exposed via the violet and green wires in the harness, and configurable via COM2 tab on the system pages.

Edit: Or, what fast-typing Brian just said. :)

--Paul
 
396 & 496 data port is USB on the back...

That USB port on your 296 is only used for uploading and downloading data from your computer if you want to update the Jeppesen aviation database or upgrade the 296 software, which is currently version 5.80. It works with MapSource to program memory cards in the memory slot for use on Automotive operations for 296 and 396 when a computer is connected. Otherwise, the USB port on the 396 and the 496 will operate the XM satellite radio receiver to get weather data and music. There is also a miniature analog stereo audio port on the back of the 396 and 496 to feed into the intercom system.

I use my 296 port 1 to drive my Dynon D-10A and my autopilot. The second serial port I use on a connection to my Garmin AT SL-30 to feed VHF OUT radio frequencies from the GPS to the radio.

Since the SL-30 can also send data from it to other devices, I have a switch on my panel that allows me to select data from the GPS to the Dynon, or the NAV data from the SL-30 to the Dynon. The D-10A can show an HSI screen for ILS or just plain VOR type displays. Since I already had the GI-106A OBS resolver, I did not really need that extra feature on the Dynon unit, but it is there.
DSCS0121.JPG
 
If you are starting with a 296 and plan to move to a 496, I highly recomend you use Port 1 or you will be rewiring later.

So there was a rumor that a tornado was in the vicinity of the airport late last night, so I went out to see if there was any damage. OK, fine, I used it as an excuse to my wife to go finish wiring the AP to the 296.

Blue wire to blue wire (Port 1), configure the 296, configure the TruTrak for 4800 baud and -- voila!

I'm almost done with the panel. Most of the rest of the wiring has to do with the engine. So far, everything that needs to talk to each other is talking to each other, which impresses me no end.

Thanks for the assist!
 
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