H

humptybump

Well Known Member
from Garmin:

Ver 6.0 of the 695/696 system software has a bug and that is the causing "NAV LOST" for the serial out data. Garmin is working on a fix and hopes to release revised software this week. DO NOT UPDATE FROM Ver 5 to Ver 6.0. You can't go back once you install a higher version.

Note this is a NEW issue created by the July 2012 firmware update provided by Garmin.​

I found the above posted over on the Dynon forums.

Explains why my autopilot (affectionately called Yoda) was dropping out frequently on my flight two days ago.

Yoda lost track of the droid army after receiving bad intel from the high council.
 
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GPSMAP 69X V6.00 Software Issue

Yes, an issue has been identified with the new software that was recently released to support the GDL39. A couple of clarifications.
  1. The GPSMAP 69X and GDL39 work just fine with no problems. The GPSMAP 69X does not lose navigation.
  2. The issue is only experienced by those that are using NMEA Out data streams to external devices (with and without the GDL39). The periodic NMEA Out transmissions can be interrupted at times causing the external devices using the data to indicate issues (such as Nav Lost).
  3. We expect to have new software in a short time to correct the issue. We flew some new software with improved prioritization of serial data output over 260 nm this morning and didn't experience any issues, so we believe we are close to releasing improvements.
  4. Those that prefer to downgrade to V5.00 may do so, but GDL39 support will be lost and user settings will be lost. User preferences will have to be manually restored. Contact us at the email address below if you need to downgrade for some reason before we have a new version with GDL39 support to fix the issue.
We apologize for any inconvenience this has caused.

Steve
 
Garmin Steve!

Is this related to the G3X software v7.0?

I am preparing for a GDL39 install and I installed 7.0, now my AFS auto pilot cycles "GPS OK" then "NO GPS". On a 2.0 flight today it was consistent and did it every 5-10 min.

Since the AFS A/P is a secondary device feed by my G3X it seems like I have the same issue as the 696.

Thanks,
 
Hello John,

Yes, unfortunately same issue. We will be releasing new versions of at least GDU 37X (G3X) and GPSMAP 69X soon to restore the previous performance of the serial output.

If you can't wait and need to downgrade to G3X V6.40 and don't have a copy, let us know.

Steve
 
Thanks for the quick response Steve!

Nope, I will tough it out with the tiny bug :D

I only fly VFR and on my 2 legs today of about 1.5 hrs I really didn't have any big issues.

It only indicated NO GPS for a half of second and I never lost navigation and the auto pilot seemed to "track" ok.

Have a good weekend.
 
New Software for GPSMAP 69X and G3X

We just released new software for the GPSMAP 69X and G3X (and standalone GDU 37X) that fixes the issue with intermittent loss of NMEA Out to external devices.

GPSMAP 695/696 V6.10

G3X V7.10

Again, we apologize for the inconvenience.

Thanks,
Steve
 
Tanks! I just received my email about the new firmware. I've loaded it but I won't be able to test right away.

Thanks for the quick turn-around.
 
Garmin Support Engr question

Could whatever solution that fixed the Nav lost data stream problem with the 696 fix the same issue in the 496 with the Dynon EFIS. According to Dynon this is a 496 bug?

One can only hope. Maybe Christmas will come early.
 
Pmerems said:
Could whatever solution that fixed the Nav lost data stream problem with the 696 fix the same issue in the 496 with the Dynon EFIS. According to Dynon this is a 496 bug?

One can only hope. Maybe Christmas will come early.
Click to expand...

Paul,

The long term NAV Source Lost error has been around for years now.

It is not specific to the 496. It has been reported on the entire line of 296-396-496 series, the 696 and with the older Aera units. It has even been reported on other brands as well but not as much as with the Garmin units but that may be because the Garmin units are more popular. I have not seen the issue yet with my 796 but I typically fly with the 430W as the source and the ARINC 429 interface does not have the issue.

EDIT:
Regarding the long term NAV source lost issue with the Dynon AP:

Let me be clear. I do not think the issue is with the Garmin GPS's or the Garmin NMEA data stream. I personally think the issue is in Dynon's code.

Reasons I think this:

•No other user of Garmin's NMEA data stream have reported an issue.
•People with other brands of GPS's have reported the same issue.
•I have spend hours and hours logging NMEA data from my Garmin GPS's and have never found an error in the data stream
 
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Same A/P problem with the 796

Flew to Pecan Plantation yesterday and had the same problem with the 796 that has been reported here for the 696 (and fixed with a software update). This is the second flight with 796 and the same results, the A/P engages and then drops out frequently. I have tried both NORMAL or FAST data stream settings with no change in results and the A/P is basically unusable. I have the NMEA &VHF Out selected for the data stream same as the 496 (I tried just NMEA out with the same result). System is up to date according to Webupdater V 3.0 I think)
The 796 directly replaced a 496 and the RS232 is connected to the autopilot/dynon/sl30 using the existing 496 wiring as before (SERIAL 1 blue TX wire from bare wire harness). A/P is a TT ADI II which worked rock solid with the 496.
Dynon D100 and HS34 works fine and the SL30 COMM and NAV frequency upload functions work fine.
Maybe Steve could comment about whether this is the same problem and will be fixed with the upcoming 796/GDL39 software update.
Maybe Andrew has some TT insight.
I could try moving the RS232 to serial port 2 but assume the driver is the same for both ports. I need to move the serial anyway because the GDL39 has to talk to port 1. (read this part after I had wired the 796:mad:)
Not a huge inconvenience as I can fly track mode and the 796 does pop up a message at the waypoints telling you the DTK to the next waypoint but I would like to get the system working again for long flights.

Another thing I noticed yesterday on the flight back was a change of touch screen sensitivity that appeared to be a function of the screen face of the 796 getting hot (sun from behind shining directly on panel), took a more deliberate press rather than a touch to change settings/screens.
Overall still very impressed with the unit.
 
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I have not received my GX3 system from Stein yet so I speak from generalities. No idea when the update came out however, I usually am not of the "frontier sprit" when it comes it comes to those. In other words I wait at least a month before I do it. Usually someone is screaming by then. Now if the last one was "bad" then I update 38 seconds after its released! :D
 
uk_figs said:
Flew to Pecan Plantation yesterday and had the same problem with the 796 that has been reported here for the 696 (and fixed with a software update). This is the second flight with 796 and the same results, the A/P engages and then drops out frequently. I have tried both NORMAL or FAST data stream settings with no change in results and the A/P is basically unusable. I have the NMEA &VHF Out selected for the data stream same as the 496 (I tried just NMEA out with the same result). System is up to date according to Webupdater V 3.0 I think)
The 796 directly replaced a 496 and the RS232 is connected to the autopilot/dynon/sl30 using the existing 496 wiring as before (SERIAL 1 blue TX wire from bare wire harness). A/P is a TT ADI II which worked rock solid with the 496.
Dynon D100 and HS34 works fine and the SL30 COMM and NAV frequency upload functions work fine.
Maybe Steve could comment about whether this is the same problem and will be fixed with the upcoming 796/GDL39 software update.
Maybe Andrew has some TT insight.
I could try moving the RS232 to serial port 2 but assume the driver is the same for both ports. I need to move the serial anyway because the GDL39 has to talk to port 1. (read this part after I had wired the 796:mad:)
Not a huge inconvenience as I can fly track mode and the 796 does pop up a message at the waypoints telling you the DTK to the next waypoint but I would like to get the system working again for long flights.
Click to expand...

Hello Dave,

Sorry to hear that you are having problems driving your TT ADI II autopilot with the Aera 796. I think you are telling us that GPS TRK and ALT modes are working fine on the autopilot, but GPS NAV mode is not.

This is the first reported problem of this type that I am aware of, and isn't something we have targeted for improvement in the next software release.

It is interesting that you can fly track mode since the GPS track data is also coming from the 796. Similarly, it sounds like the other devices using the serial output from the 796 are not experiencing any issues.

We will do some testing on the Aera 796 RS-232 output and see if we can spot anything that could explain this. It might help if you send us an email with this information in case we want to contact you and ask some additional questions about your installation, autopilot software, flight plan, etc.

I am confident we will find a solution.

Thanks,
Steve
 
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Make sure you have 9600 baud selected on your autopilot. With NMEA &VHF Out selected it only outputs at 9600 baud regardless of what baud rate is set.

George
 
Baud rate

Interesting comment on the baud rate, I just looked at the TT ADI install manual and it suggests the optimum baud rate setting for handhelds is 4800 with FAST mode selected. I am sure I set it up per the 496 instructions (4800 baus) and it worked well for 3 years. The 796 does not appear to have the choice of selecting the lower baud rate but the A/P does have the ability to change the baud rate as part of the setup procedure so I will try that next.
Thanks
 
I am not sure why that is on the 696. I think its the same on the797. Some modes put the output in 9600 baud regardless of what baud out rate was selected. I lost my autopilot for a few days because of the issue until a garmin tech pointed out the error. I had talked with them before but this guy new instantly what the problem was. Changed the autopilot to 9600 baud and everything played nice again!

George
 
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Baud rate

I sent this to Dave directly, but thought we should post it here to clear the air. There is nothing mysterious about baud rate. Both ends just have to be setup the same.

We operate the serial port at 4800 baud when that data rate is sufficient for the data which must be transmitted and generally use 9600 baud when the higher data rate is required to get the job done.

You can press on the question mark next to the selected format on the Aera 79X interface page to see the baud rate used for that selection. Regardless of what the AP manual says, you must select the autopilot baud rate to match what is being transmitted by the Aera 79X or other GPS.

NMEA Out (Normal or Fast), set autopilot to 4800 baud
Aviation In/NMEA & VHF Out (Normal or Fast), set autopilot to 9600 baud
GTX TIS-A In/NMEA & VHF Out (Normal or Fast), set autopilot to 9600 baud

Thanks,
Steve
 
uk_figs said:
Interesting comment on the baud rate, I just looked at the TT ADI install manual and it suggests the optimum baud rate setting for handhelds is 4800 with FAST mode selected. I am sure I set it up per the 496 instructions (4800 baus) and it worked well for 3 years. The 796 does not appear to have the choice of selecting the lower baud rate but the A/P does have the ability to change the baud rate as part of the setup procedure so I will try that next.
Thanks
Click to expand...

My apologies if the manual led you to believe that you HAD to set it to 4800. You don't. The autopilot doesn't care which baud rate you use as long as it's matched to the GPS. With the Garmin handhelds (no personal experience withthe 796 yet) there are two options that work. NMEA IN/NMEA OUT which runs at 4800 and Aviation In/NMEA & VHF Out which runs at 9600. Either of them SHOULD work as long as the baud rate of the autopilot is set to match.

EDIT: And that's what I get for forgetting to hit the "Post Reply" button. :)
 
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796 NMEA Out

I plan on setting the ADI II on 9600 tomorrow and see if that fixes the issue, I did in fact try the 796 NMEA Out (4800 baud) setting on Sat in the air and the A/P would not go into NAV mode, may still have been a mismatch for some reason.
 
All seem well now

Checked all the settings yesterday on the ADI II, HS34 and the 796 and made sure they all matched with respect to baud rates. 796 to the A/P is on serial #2 now as the GDL39 is on serial #1. Output on serial #2 that feeds the other systems is set to "Aviation IN/NMEA & VHF Out" and "FAST" mode. This sets the 796 to output at 9600 baud and data every second, checked the setup pages for the A/P and the Dynon were also at 9600 and paired the GDL39 with the iPad. Went flying to check everything out and although it was a fairly short flight it was fairly turbulent and the A/P seems to be working fine and did not drop out once. Switched waypoints etc and the A/P stayed locked in so so far so good. Looks like it was user error :eek:
 
uk_figs said:
Checked all the settings yesterday on the ADI II, HS34 and the 796 and made sure they all matched with respect to baud rates. 796 to the A/P is on serial #2 now as the GDL39 is on serial #1. Output on serial #2 that feeds the other systems is set to "Aviation IN/NMEA & VHF Out" and "FAST" mode. This sets the 796 to output at 9600 baud and data every second, checked the setup pages for the A/P and the Dynon were also at 9600 and paired the GDL39 with the iPad. Went flying to check everything out and although it was a fairly short flight it was fairly turbulent and the A/P seems to be working fine and did not drop out once. Switched waypoints etc and the A/P stayed locked in so so far so good. Looks like it was user error :eek:
Click to expand...



Typically the original Dynon gear does not work 100% when the Garmin GPS's are set to FAST on the NMEA settings.

Did you happen to look at your Dynon's HSI and verify that it was working properly during this test flight?
 
Dynon settings

Brantel
Yes I did and it seemed to be working fine, maybe it is the fact that I have the HS34 installed that makes the difference.
The puzzling thing about this setup is that when I got to the A/P baud rate setup page it was already displaying "96" for the correct baud rate and the HS34 serial setup page was also on 9600. This implies that I had the 496 on 9600 in which case the 796 should have worked out of the box, I cannot check the 496 settings as I have it back to factory defaults for the buyer.
Only real difference for yesterdays exercise was moving the systems to 796 serial #2 as the GDL39 has to go on serial #1.
Both Garmin and TT say there should not be a problem so as long as it stays working I am fine.
 
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