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Garmin GTR 225 Radio Skyview

Jamesey

Well Known Member
Finally getting to the end of one of the longest RV 12 builds on record. At the stage where everything appears to go wrong.
RV 12 with the early Skyview conversion harnesses. GTR 225 radio. Everything appears to be connected and the settings in Skyview verified. Still have big red cross on the Skyview screen where the radio frequencies should be.
Have checked everything I can think of. What am I missing?? Any help suggestions from the experts out there appreciated.
 
No expert, but the Garmin radio communicates with Skyview via a serial port. Have you checked the serial ports setup menu to see if the GTR 225 is specified on one of the ports?
 
And I believe, it's port 4 ? Also, was your wiring harness built with the shielded data cable that goes from the box to GTR225 ? Also make sure the baud rate is set correctly.

I know, having an early RV-12 and box, for my SL-40, I had to buy an additional separate shielded cable from Van's to get that information to show up at the top of my Map, as it was not included in the original wiring harness, but was subsequently added later on, in production. You could probably make your own cable, later on, folks said the shielding wasn't necessary, just need the pins, and pinout locations.
 
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Tony,
"No expert, but the Garmin radio communicates with Skyview via a serial port. Have you checked the serial ports setup menu to see if the GTR 225 is specified on one of the ports?"

From the Dynon Skyview Manual the following options selected:
Configure the serial port: SETUP MENU > SYSTEM SETUP > SERIAL PORT SETUP > SERIAL
PORT x SETUP > SERIAL IN DEVICE > (Configured for Serial Port 4)
FUNKE ATR833 or
GARMIN GTR 200 or
Full TY91/92 8.33 kHz support depends on a future software update from Trig.
SV-D700 / SV-D1000 / SV-D1000T Installation and Configuration
SkyView System Installation Guide – Revision W 4-23
GARMIN GNC 255 A/B or
GARMIN GTR 225 A/B or (This radio selected)
TRIG TY9X 25KHz ONLY
TRIG TY9X 8.33/25KHz
This will automatically set the SERIAL IN FUNCTION, SERIAL IN/OUT BAUD RATE, and SERIAL
OUT DEVICE.
Set the radio status to be displayed on the top bar: SETUP > SYSTEM SETUP > DISPLAYED COM >
(device you chose above) (PORT x) (“DISPLAYED COM” does NOT appear as an option. It has a setting for “PRIMARY COM” which shows GARMIN GTR 225 A/B selected on Serial Port 4)
and
SETUP MENU > SYSTEM SETUP > DISPLAY COM IN TOP BAR: YES (This option selected)

Still searching:)
 
Niner Bikes,
And I believe, it's either port 3 or port 4 ? And is Baud rate correct. Also, was your wiring harness built with the shielded data cable that goes from the box to GTR225 ? Also make sure the baud rate is set correctly.

I know, having an early RV-12 and box, for my SL-40, I had to buy an additional separate shielded cable from Van's to get that information to show up at the top of my Map, as it was not included in the original wiring harness, but was subsequently added later on, in production. You could probably make your own cable, later on, folks said the shielding wasn't necessary, just need the pins, and pinout locations.

Per previous reply to Tony, radio set up on serial port 4. Radio was supplied with the mounting tray and harness by Vans, admittedly some time ago. I suppose it is possible harness has been modified through experience, will also contact Vans.
 
One other thought; have you loaded a .dfg Van's settings file for the GTR225? Your USB stick containing your downloaded Van's EFIS software and settings files should contain a file that looks like this or similar:
12-GTR225-PRE-
SETS_0...2-15.dfg

You would have loaded this during your initial setup of the SV, but I thought I would ask.

My download did not include a .dfg for the GTR225, only one for the GTR200. If you don't have it you may have to ask Van's for it.
 
You did not mention if you were seeing any activity on the port monitor TX and RX counters for serial port 4.

You may want to check your GTR225 Serial Port IO MODE on the System Configuration menu, it should be set to NMEA (the default setting is 'NONE').

If you have a PC/Laptop with a RS232 serial port you can use a HyperTeminal program to see if the GTR225 is sending the data to pin 9 of the SV D37 connector. The GTR is set for 9600, 8, 1, None and you should be able to see the NMEA 0183 string on pin 9 if the wiring is correct.

John Salak
RV12 N896HS
 
Software Updates

Part of my problem could possibly be Software Status. The radio as supplied by Vans has Software Version:
Display 2.01
COM 2.11
Latest Versions I can find (Garmin Bulletin Oct 12 2017) are:
Display 2.20
COM 2.30
It would appear I'm a tad behind the times. Update I thought. Well whilst the GTR 200 series update is available on the Garmin site, for the GTR 225 series you get:
Software Information Currently Unavailable
This information is either coming soon, not applicable, or no longer available for this product.
As this is a current radio (still supplied as one option for the 12IS) does anyone know how you update the GTR 225A ???
 
The original wiring harness on mine (2013 SLSA) didn't come with the RS-232 wire out from the comm radio to the Skyview. Was easy to add, if you like adding wires.
 
Skyview to GTR 225 Issue Fixed

Comment made by John Salak post #7 spot on:

"You may want to check your GTR225 Serial Port IO MODE on the System Configuration menu, it should be set to NMEA (the default setting is 'NONE')."

Changed setting and all is well.

Thanks for the tip.

Jim D
 
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GTR 225 Software Updates

Further to post #8, for the record and in case any GTR 225 users have the same issue and search this forum in future.

I sent a query to Garmin UK as follows:

I have a GTR 225A radio supplied through Vans Aircraft Inc as part of a Vans RV 12 light aircraft kit. Software Version: Display 2.01, COM 2.11 I want to update but your site says this is no longer available. This is a current radio you sell. Why can't I update? The GTR 200 updates are readily available on the Garmin website.

Garmin responded as below:

Apologies for any inconvenience. The reason for this difference is that the GTR 200 is an uncertified radio, (which for that reason and the fact that it only has 25KHz spacing cannot be use in Europe) whereas the GTR 225A is a fully certified, TSO'd product. All of the operating software for certified units are restricted to Garmin installers/dealers who have undergone the necessary training and have access to the Service Bulletins etc. A dealer will be able to update the software for you, or if they are happy to provide it to you so that you can install it yourself in your uncertified aircraft, that may also be a possibility.

I was fortunate that one of the UK distributors helped out on this and supplied the update with full instructions. Update successfully carried out today.
 
GTR225 Skyview Display

Comment made by John Salak post #7 spot on:

"You may want to check your GTR225 Serial Port IO MODE on the System Configuration menu, it should be set to NMEA (the default setting is 'NONE')."

Changed setting and all is well.

Thanks for the tip.

Jim D

Jamesey, how did you change the serial IO Mode, mine is greyed out (please see photo)? I also have the big red cross on my display.

BTW, my radio came with Software version display 2.20, COM 2.30 Has the version you have acquired superseded this ?

TIA
 

Attachments

  • GTR225_Configuration.jpg
    GTR225_Configuration.jpg
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Gray out

Bob,

That is normal. If you select one of the radios in the menu, Dynon has set the perimeters for that radio for you, and does not allow you to change them, that is why they are grayed out.

Brian
 
Radio

Bob, from memory part of the problem was the Vans RV12 presets go for the American setup of the Gtr200. Once I changed that to the 225, all fell into place.
 
Thanks Guys,
The problem may be that I installed the GTR200 Pre-sets initially. When I realised my mistake, I changed the settings in the Skyview Setup to GTR225 (as can be seen in the photos), but I still cannot get at the greyed out Serial IO field.

I've searched for a GTR225-PRE-SET...... dfg file without success. Anyone out there have one or know where I can find it, so I can reload the correct configuration file ?

TIA
 
Radio

Bob, going up to airfield sometime this week (Fishburn). Will hav a look in my settings and get back to you.
 
Solved !

The solution came from Harry on the UK RV-12 WhattsApp Group, (James, PM me if you would like to join). The man is a legend !

I had misread your and John Salak's posts, I thought the change to NMEA needed to be made via the Skyview Configuration, whereas the change is made via the GTR225 Sys Configuration.

Turn on GTR225 whilst holding in the frequency knob, go into SYS Configuration, Serial Port, and change from NONE to NMEA.

Thanks Guys.
 
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