Problems with Devo F12E nightly builds

I have been trying to update my F12E with Deviation mainly to get persistant telemetry but it seems the current nightly builds are very much broken. Updating using Deviation Uploader 0.9.0 results in a broken filesystem, but I found this can be fixed by manually copying the devo.fs over. Going through the menu sometimes results in getting stuck in submenus, and the only way to recover is to turn off transmitter. The GPS telemetry displayed seems way off, altitude is a large number and the current date is in the year 2048. The GPS coordinates also seem to be offset by a couple of km.

Is there any build available for F12E that is known to be working?

I will take a look and get back to you.

Recently there are many changes getting into the tree and it may need a little bit time to stabilize again.

Thank you for your testing and we love hearing your concern, feedback & suggestions.

Thanks very much. Most of these problems I can work around and the build is generally very flexible and very usuable, much better then the original Walkera firmware. The only thing that is a killer for me is the GPS coordinate telemetry, it is way off, so I will not be flying with that. I just tested again by flashing the original Walkera firmware back and the GPS coordinates displayed there are correct.

I am testing on a QR-X350 Pro that I have replaced the RX703A with a RX705 receiver to get telemetry. I have attached two screenshot showing the difference in GPS coordinates for Walkera and Deviation. I blacked out a portion of the GPS coordinates for privacy reasons.

If you want me to test something out I am willing to help out in any way I can.

Seems like the QR-X350 format might be pretty close. kbg, do you have an FTDI adapter and are able to capture serial data from the trainer port? If so I'll make a test build to dump the telemetry data.

Yes the Walkera format seems to be in decimal degress DD.DDDDD, so for example when the display is "64°12.345N" it's actually "64.12345" in decimal degress. Don't know why they have that extra dot in there, it's confusing but the coordinates in decimal degress are correct.

Now I don't understand but isn't the GPS coordinates sent in the Devo telemetry in some standard format and different then what is actually displayed on screen? Given that the the QR-X350 Pro GPS can send the correct GPS to the F12E telemetry then obviously the F12E can correctly interpret the coordinates. Perhaps there is some flag that specifies which format is used? Maybe Deviation is interpreting DD.DDDDD as DD MMMM incorrectly?

Unfortunately I don't have an FTDI adapter and not sure if I can get one easily where I live. I will probably have to order it from china and that will take a while. Yes it seems to me that Walkera just simply displays whatever it receives so that explains the weird format on screen. So if Deviation is expecting DD MM.MM and does some calculation with DD.DDDDD that then that would probably overflow the coordinates.

Test build (070ed6e) available. Enables debug log and prints Devo telemetry packets to the log.

With this build you should see an extra "debug log" main menu item. In that page.we're interested in lines that start with "3" after the line number. May need to make changes to the build if the data is coming too quickly.

Ok I installed the build and took a 10 sec video of the debug log and put on my Google Drive:

debug log video

Thanks that's very helpful.

The longitude telemetry string is "02186.3545W". As vlad_fy pointed out the display value in the stock firmware "21° 86." is not correct, or at least not normalized. It's essentially the same as the Deviation displayed value of "22° 26.". kbg, what is your actual GPS longitude (from cell phone or other source)? Maybe the QR-X350 is not normalizing the value correctly for some reason. In the images you posted the latitude is the same in deviation and stock firmware.

The altitude is bouncing around 3-4 meters. Is that correct?

The speed data is "9999.90000.0". Not obvious how to decode that. Is it possible to record some data with the aircraft moving?

The timestamp telemetry doesn't have any data - all nulls. Was the GPS "locked" with enough satellites for a good link?

kbg wrote: I have been trying to update my F12E with Deviation mainly to get persistant telemetry but it seems the current nightly builds are very much broken. Updating using Deviation Uploader 0.9.0 results in a broken filesystem, but I found this can be fixed by manually copying the devo.fs over. Going through the menu sometimes results in getting stuck in submenus, and the only way to recover is to turn off transmitter. The GPS telemetry displayed seems way off, altitude is a large number and the current date is in the year 2048. The GPS coordinates also seem to be offset by a couple of km.

Is there any build available for F12E that is known to be working?

Count me in with issues with the F12E and nightly builds. I have not been able to get one to work as of yet. How do you manually copy the devo.fs over? I dont see a download for the F12E in the stable folder, is that not available yet?

hexfet wrote: Thanks that's very helpful.
kbg, what is your actual GPS longitude (from cell phone or other source)? Maybe the QR-X350 is not normalizing the value correctly for some reason. In the images you posted the latitude is the same in deviation and stock firmware.

The altitude is bouncing around 3-4 meters. Is that correct?

The speed data is "9999.90000.0". Not obvious how to decode that. Is it possible to record some data with the aircraft moving?

The stock GPS coordinates are correct but they are not normalized and are being displayed in decimal degrees.

I will send you my actual GPS coordinates in PM message.

I am just testing this stationary in my backyard. Not sure I can test this in flight, the weather currently is not very good. But since the quad wasn’t armed it’s possible that there is was no speed data until arming. I will test this with arming as soon as I get home.

The timestamp telemetry doesn't have any data - all nulls. Was the GPS "locked" with enough satellites for a good link?

Yes I believe so. Possibly the timestamp is not being sent, because it’s not being displayed anywhere in the stock firmware.

I am not to worried about the timestamp,speed and altitude, the most valuable are the GPS coordinates.

vlad_vy wrote:

hexfet wrote: I don't see sign to distinguish DD.DDDDDD from DD MM.MMMM.

Yes doesn't seem to be any way to detect this. I have been looking at videos online from users using the stock firmware and it seems that the GPS is being sent like this for all Walkera models. Here is an example video from someone using Walkera Tali H500. The latitude degree minute in the video is 69 which is not normalized.

Tali H500

Maybe it would be possible to add a configuration for the GPS format, so that we can select either DDMM.MMMM or DD.DDDDDD?

rklunder wrote: Count me in with issues with the F12E and nightly builds. I have not been able to get one to work as of yet. How do you manually copy the devo.fs over? I dont see a download for the F12E in the stable folder, is that not available yet?

There is no stable version yet. To fix the file system issue you should update the firmware as usual with Deviation Uploader. Turn off the transmitter after flashing, then hold down ENT button and turn back on, this will enable USB mode. Delete the devo.fs that is on the transmitter, open up the zip firmware file and copy the devo.fs file there over to the transmitter. Turn off and on as usual and it should work.

The test build is updated (724bdee). The Devo telemetry protocol option is changed from "On, Off" to "Std, X350, Off". When set to X350 the Long/Lat telemetry is interpreted as decimal degrees instead of degrees decimal minutes.

Yes this works. The GPS coordinates display correctly now.

When I get the chance I will try to test the speed and altitude and post my findings here, but I think the timestamp is something that just isn't available in the data.

I hope these changes will make it into the nightly build at some point?

Thanks for the excellent support.