Latest GTX-327 firmware

Scott, not sure what latest is, but I can confirm that 2.09 is a "good" one and this functionality works fine in that version.

Scott Will said:

Been trying to get my transponder to automatically switch from ground to air using the serial data. I know it's wired correctly and it's already getting the encoded altitude from the EFIS just fine. Called Garmin in Kansas and they said it's a firmware issue. Does anyone know what the latest firmware version is? Mine is 2.02 and it doesn't have the RS-232 config pages.

Has anyone upgraded their firmware and if so do you mind if I ask how much it cost?

Thanks!!

Click to expand...

I think it highly unlikely that this is related to the firmware since I've had a 327 since 2000 and it does the auto STBY/ALT. What GPS are you using to feed the aviation data to pin 2?

There are two RS-232 input ports on the GTX-327. One on pin 2 and one and pin 19. The one on pin 19 is for Serial altitude data, while the one on pin 2 is for Aviation data and it is the one that controls the transition from ALT to STBY once the GPS groundspeed exceeds 40kts. Make sure you are using this port.

I know some have stated that it uses the serial altitude data to perform this transition but this is NOT the case, at least with the version I have. It is the GPS groundspeed on pin 2.

Scott Will said:

In talking with Garmin and going thru all the wiring possibilities and what not, it does seem (it is) related to firmware. Last week I added a pinout from my GRT EFIS for GPS data to pin 2 on the transponder. No workie. Garmin said the RS-232 inputs weren't fully utilized until the later firmware came out. When it powers on my transponder says Garmin 1999-2000, version 2.02. I am getting the encoded altitude correctly from my GRT EFIS. You would think that would do it but it doesn't on mine.

Click to expand...

Is that GPS EFIS data from the GRT formatted as Aviation or NMEA? If you are using the same serial output that is feeding the serial altitude, then I can see a problem. Is this your only GPS on board? If not try feeding pin 2 of the 327 with a "pure" GPS sending Aviation NOT NMEA data. Maybe the new firmware allows transition using NMEA and not just Aviation data. I'm feeding my 327 with a GNS-430.

At one time, Garmin told me that this function will only work with the 430 series of GPS.

I tried connecting to my GPSMap 296 and auto mode C did not function.

However, when i disconnected it, the auto mode C function started working!

I believe the Garmin algorithm is that if it sees a rapid increase in altitude from the encoder, it assumes that you are flying and switches the transponder to mode C. It's a pain when you are flying formation, but it's handy at other times.

For obvious reasons, it will not automatically switch back to standby. It can't determine when you are on the ground.

V

vlittle said:

At one time, Garmin told me that this function will only work with the 430 series of GPS.

I tried connecting to my GPSMap 296 and auto mode C did not function.

However, when i disconnected it, the auto mode C function started working!

I believe the Garmin algorithm is that if it sees a rapid increase in altitude from the encoder, it assumes that you are flying and switches the transponder to mode C. It's a pain when you are flying formation, but it's handy at other times.

For obvious reasons, it will not automatically switch back to standby. It can't determine when you are on the ground.

V

Click to expand...

The reason it did not work is that the 327/330 uses aviation data stream format, output from the 430 as an example, to start mode C. It uses ground speed not encoder information. 40kts is the default but is configurable. For other functions, flight timers and so forth, it uses the automated determination system with squat switches and encoder info.


Best,

firmware related after all

Update ... Alan came over and put his brand new GTX-327 in my panel and we had it working instantly with no wiring changes at all!!! So it is related to firmware (2.02 does not work). Consequently, we landed immediately after finding this out, went back to my hangar, picked up my older 327, took off again, flew to KWDR and dropped off the 327 for the firmware upgrade.

Scott Will said:

Update ... Alan came over and put his brand new GTX-327 in my panel and we had it working instantly with no wiring changes at all!!! So it is related to firmware (2.02 does not work). Consequently, we landed immediately after finding this out, went back to my hangar, picked up my older 327, took off again, flew to KWDR and dropped off the 327 for the firmware upgrade.

Click to expand...

Can you provide for the benefit of others what you were feeding the GTX-327 that required the newer firmware? I know you mentioned GRT GPS data but was not exactly clear on what format? NMEA? Also, does it transition from STBY to ALT and then back again to STBY or just STBY to ALT? As I mentioned using my GNS-430 sending Aviation data works fine with the original firmware. Garmin portables have an "Aviation In" setting but no "Aviation out" setting so this probably explains why it does not work with the portables. It sounds like Garmin has now provided support for the auto STBY/ALT using NMEA data. Can you confirm? This should help those with similar configurations?

Obviously you can tell Scott is a little excited ... And rightfully so... Ya see, even us Lancair drivers get to claim lots of right seat RV time... I think I own the record at the moment at least in 410S - Scotts airplane.

It's one sweet ride mind you.... But alas, before I forget why I'm writing this.

Ok, so let's clear the air.

Scotts Transponder a GTX-327 with v2.02 firmware would not automatically swtich from STBY to ALT at takeoff, nor would it automatically switch back to STBY once he landed. You had to press the buttons in order for that to function. In the 2.02 firmware, there is one setup that provides for the serial interface that the encoder sends it's pressure altitude information on and one serial port that can be used for the automatic switching. Scotts worked for encoder information only.

We talked to GRT and they said that a 327 should only require *one* serial port for *both* encoder info and the data that is required to cause the auto switching. They told us that the GRT needed to be configured for the format that Scott mentioned above, and that the 327 needed to be in the FADEC W/ALT mode. That's when we realized that there was a major firmware upgrade that existed. My 327 has 2.09 in it and it's menu system matched exactly what GRT told us, but Scotts didn't. Hence our interest in swapping out the 327's. With mine installed in Scotts airplane, we made *no* changes except for configuring the single serial port for the correct format (FADC w/ALT). Also, the newer firmware has a diagnostic page in the configuration menus that allow you to see the decoded serial information. That is where wesaw that is was getting SAT, IAT, PALT, DALT, etc in the data stream from the GRT. When that started to work (btw, that screen doesn't exist in the 2.02 firmware), we knew we were golden, but went for a lap around the pattern just to confirm the auto switching.

As mentioned, immediately at rotation, it switched. BTW, I don't think it detected the rotation, it more than likely detected the speed, or pressure change. To be clear, we left the unit in STBY mode and pulled out on the runway, lined up and advanced the throttle. At rotation, the 327 automatically switched to ALT mode, it remained in that mode until we touched down, then 24 seconds (it's configurable) after touch down, it automatically switched back to STBY mode. We never touched a button.

As a side benefit, this auto function, also resets and starts the flight timer automatically (resetting of it is also configurable).

Ok, now before you get all excited, the above does not directly translate to the 330. I have been working thru some wiring glitches in a Lancair that has a 430 and 330 and to get them to perform the same functions as above required an ARINC interface between the two, not a serial one. It also requires a slightly different configuration, but once its right, it works exactly the same.

So, there ya have it. The 2.02 software may function if driven by a 430, but it won't in the formats discussed above with a GRT display. But get the firmware updated and it certainly will.

Hope this helps,

A few folks have contacted me offline for additional clarification so I'll post here for the benefit of all.

OK, it sound like with the newer firmware, the GTX-327 can use NMEA or *F/ADC W/ALT* data to transition between STBY and ALT. When using a Garmin panel GPS or any unit capable of sending "Aviation" data, the original firmware is OK.

Here is how mine is wired in my Cardinal:

I don't have a serial encoder represented by the dashed lines. If I were to replace the A-30, I would feed serial altitude to the 327 AND the 430 from it.

I'm still am not sure, will this work with a 295 portable or not. Also will it work with out GPS at all (from the encoder) switching from standby to ALT only?

Another 327 question, are the buttons supposed to be lit? Mine are not and I can't see them well enought to change codes at night unless I shine a light on them.

Sorry for the ignorant questions but this seemed like a good place to ask

Thanks,
Neil

Automatic Altitude Determination and Flight Timer

I ran across this thread when searching for a solution to my problem with the GTX327 and Garmin 430W - thought I'd post and see if any of you have a possible solutiion.

1. My GTX 327 is version 2.02.
2. My unit switches automatically to ALT mode on take off and back to standby upon landing - after 24 seconds, that is.
3. I'm trying to get my flight timer to start counting at takeoff but no luck so far. I've seen several references that it should start counting when Automatic Altitude Determination is activated but no luck so far.


Any help greatly appreciated.

Don
RV7A
C177B Cardinal

Just a thought, are you looking at the right timer? There are two: flight and count-down.

or check the congfig:

5.2.6 OPERATION CONFIGURATION Pages
5.2.6.1 First Configuration Page​

[FONT=TimesNewRoman,Bold][FONT=TimesNewRoman,Bold]

​

​

[/FONT]​

[/FONT][/FONT]

Available choices are MANUAL, CLEAR and ACCUMULATE. Selecting CLEAR resets Flight Time to
zero and starts the flight timer when lift off is sensed.​

[FONT=TimesNewRoman,Bold][FONT=TimesNewRoman,Bold]

Selection Description
MANUAL​

​

[/FONT]​

[FONT=TimesNewRoman,Bold][FONT=TimesNewRoman,Bold]

CLEAR​

​

[/FONT]​

[FONT=TimesNewRoman,Bold][FONT=TimesNewRoman,Bold]

ACCUMULATE​

​

[/FONT]​

Also, make sure the squat switch is set to "NO"

5.2.6.2 Second Configuration Page​

[FONT=TimesNewRoman,Bold][FONT=TimesNewRoman,Bold]

SQUAT SWITCH​

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The GTX 327 Flight Time may be based on the squat switch state. The squat switch field may be set to
either YES or NO. (Default NO). If YES, sense may be set to HIGH or LOW. If set to NO, airborne
status for auto standby and flight timer features will be determined by input data. The highest priority is
GPS groundspeed. The next is serial port ADC input followed by pressure altitude change, if no other
RS-232 source is available.​

[FONT=TimesNewRoman,Bold][FONT=TimesNewRoman,Bold]

SENSE (Squat Switch Sense)​

[/FONT][/FONT]

This field can only be entered if the AIRBORNE SOURCE selection is YES.​

[FONT=TimesNewRoman,Bold][FONT=TimesNewRoman,Bold]

Selection Description
LOW​

​

[/FONT]​

[FONT=TimesNewRoman,Bold][FONT=TimesNewRoman,Bold]

HIGH​

​

[/FONT]​

on the ground, and low (grounded) when airborne.

GTX 327 Flight Timer

Alton,

Thanks for your reply. I think there must be some differences between the level of software in my 327 and yours. I'm at 2.02.

1. The GTX switches to Alt mode upon liftoff, so it must be sensing that the aircraft is airborne.

2. On my config page, I only have two options for airborne source: GPS and squat switch. There is also an option for "NO" source.

3. I don't have any choices for the flight timer, e.g. accumulate, clear, or manual.

4. The only way I've ever gotten the flight timer to work is to manually start it.

I am starting to think I need to upgrade the firmware.

don

be advised that (at least in our gtx-328, so i suppose it's probably similar with the 327 or 330) the air/gnd sensing based on gps ground speed will NOT work with standard NMEA gps format. only garmin aviation panel-mount format is accepted :-(
of course, this is NOWHERE documented. in fact, from reading documentation you even can get the opposite impression (gps serial in, 9600 baud etc...).

we had to retrofit a mechanical airspeed sensing switch because of that (after trying to troubleshoot correctly planned and installed wiring).

rgds, bernie

p.s. the other mode-s transponders on the market take NMEA without a blink of an eye...
must be another point of "apple"ization by garmin as has been mentioned regarding other units. closed ecosystem :-(

johnso29 said:

Alton,

Thanks for your reply. I think there must be some differences between the level of software in my 327 and yours. I'm at 2.02.. . .

Click to expand...

I have no idea what my firmware is. The unit was new in the fall of 2009.

NeilMcLeod said:

Another 327 question, are the buttons supposed to be lit? Mine are not and I can't see them well enought to change codes at night unless I shine a light on them.

Sorry for the ignorant questions but this seemed like a good place to ask

Thanks,
Neil

Click to expand...

There is a menu item that will let you turn the button lighting up so they can be seen at night. I don't have the manual in front of me may someone will let you know the sequence. I did this to mine and it worked great. I had to do the same for my SL30.