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Hi all,

I'm using a turnigy 9xrpro with some XJT and 8xr modules to control a pixhawk through a telemetry cable adapter, so far so good

With firmware r221 I was able to see Altitude but ground altitude stayed always at zero, it wasn't too troublesome

Since I upgraded my radio to the last version ersky9x-A3r223, I lost Altitude and ground altitude both stay at zero now and it's troublesome..

May somebody can help me to find a solution ?

Thanks a lot in advance !

Check that the telemetry programming on your model didn't change, and has the correct fields selected.

João

Not sure what you mean by "Ground altitude", Galt is "GPS Altitude".
Nothing should have changed for handling the altitude.
Please search on here for how to do "Raw Logging", then create a raw log file for about 10 seconds. Locate the logfile on the SD card, put it in a .zip file and post it here.

Mike

@João : i followed and then double checked explanations written here : https://ardupilot.org/copter/docs/commo ... metry.html
especially from the Turnigy 9XR PRO section, no more. There's a GPSAltMain check box, i don't know if it's better to enable it ? Because the pixhawk's internal pression sensor provides an altitude probably with a better accuracy than GPS one

@MikeB : Oh yes that's true, i meant Ground altitude and GPS altitude. Ok as soon as i get 5 minutes i do it

Thanks to you

Hi Mike,

Please see below my raw logging

Thanks for your advice in advance

I can see the Pixhawk data there, so it should be being processed. There may be the odd item I don't process because I haven't got the documentation to describe exactly what the format is. I don't have any Pixhawk gear myself.

First thing to try is the go to the telemetry menu and try changing the UsrProto to ARDUP (or ARDUC). This should continue to receive the telemetry but add an extra screen to the telemetry screens where more data from the Pixhawk is automatically displayed.
See what is there, Alt and gAL are both on there.

Another thing to look at is to go to the Telemetry|Logging menu. For each item, as well as a tick in a checkbox to enable logging there is a tick at the very right if telemetry data is currently being received for it. See what items have ticks to show they are being received and processed.

All the Pixhawk data is passed to scripts. We can put together a script you could run to check the received telemetry.

Mike

Ok i see it's clear I'd very pleased to lend you my pixhawk but ..

UsrProto is already set to ARDUC and effectively I've seen ticks at the very right column and I was wondering what did it mean, I can confirm you that Alt and gAlt ones are disable. Nevertheless Alt and gAlt check boxes are checked

Ready to try a script, I never done it but I'll learn

I've just posted a test version of erskyTx (on the test versions thread) that may (should!) fix your missing GPS Altitude.

I may also be able to add what you are calling the Ground Altitude, which is, I think, called "Home Altitude" in the Pixhawk data. I will need to find/choose/create somewhere to store it.

Mike

Great Mike ! I'll check tomorrow and keep you informed

Regarding "Alt" I probably read "Ground altitude" somewhere I don't remember where, but for sure it seems to be "home Altitude" instead

Franck

Hi Mike,

I've just tried your firmware and then I can receive gAlt, great !

But as you can see on the picture it seems I lost percentage of battery, it's always staying to zero too :
May I finally ask you to add (I take this opportunity..) :

Alt value from "Home Altitude"
dth value from "Heading"

"SRTL" text instead of "unknown" for the Smart Return To Land mode (new mode added one or two years ago). On the picture I was in STRL but in other modes i get the write texts

Thanks a lot

Franck

I've posted a new test version. "dth" should have distance to Home in it.
SRTL may be displayed, assuming I have the correct code number for it (21).
"Alt" is currently the altitude returned by a barometric sensor. Since there may be people already using this I'm not sure I should change it. You should find the Home Altitude is the telemetry value CUST6 (Custom 6), even in the version you have.

For the capacity, please check if you have a non-zero value in the telemetry value "mAh". Also, check you have configured the battery capacity in Pixhawk, as if this is zero, the used capacity will not be updated.

Mike

Ok Mike,

I believed "dth" meant delta heading.. Regarding "Alt" I'm agree with you for the barometric measure especially because there's a menu to reset it for instance to the ground of the lift off, but in flight this value does not change, I've to verify it again to be sure. For the battery capacity I already set all the parameters long time ago, but I'm going to see them again I maybe lost some of them. Thanks again and see you soon in the next couple of days.

Franck

Hi Mike,

I made some tests yesterday evening and here are the results :

1. The text for the Smart Return To Launch mode is ok

2. The percentage of battery and the battery icon are staying at zero (void). Voltage and Current telemetry values are ok and i've verified the type of sensor and the capacity parameters, they are ok
-> I checked the variable name used for this information within Mission Planner status (arducopter ground station software for pixhawk) and I suppose and hope they used the same in the telemetry. This name is "Battery_remainin" there are some eight with the same name, but only the first one contains the percentage

3. Alt always stays at zero in flight
-> In Mission Planner status, the variable name with the good value is simply "Alt"

4. dth displays something inconsistent, a data comprised between 0 and 120 without any relationship with the distance from the take off
-> In Mission Planner status, the variable name with the good value is simply "DistToHome"

5. Minutes and secondes in the right and up corner always stay at zero after take off
-> In Mission Planner status, the variable name with the good value is simply "timeInAirMinSec"

Franck

I'll be posting a new test version in a few minutes:
1. Good, OK.
2. May be fixed, I found an error/change in the parameter ID value for total capacity.
3. Do you have GPSAltMain set still? I may need to run some tests on this.
4. Found a bug (typo), I was using the wrong bits from the data.
5. The time in the top right is the radio TIMER1 value. I don't see anywhere in the Pixhawk passthrough telemetry where the "time in air" is sent.

Mike

If you talk about the GPSAltMain check box I never tried to enable it, do I have to ?

Any way, I will make a test tomorrow evening with your last version

Franck

If you tick the GPSAltMain box, then the GPS altitude is copied to the barometric altitude value. That value may then be reset to zero when the model is on the ground.

Mike

That is what I thought and as I said few lines above I didn't activated that box because the internal pressure sensor provides a relative altitude probably with a better accuracy than the GPS. So if we could see the measure coming from this sensor in Alt field it should be better I think.

Franck

Please check the value in the telemetry item "Cus6" (Custom 6). I'm currently placing the "Altitude from Home altitude" in there, in units of 0.1m. I don't know whether this is the barometric value or a value derived from the GPS altitude. It does have a greater precision compared to the GPS altitude, so may be the barometric value. If it is I'll put it in the normal altitude item.

Mike

I finally succeded to make a test this evening yesterday it was raining..

Here are my new results :

1. The percentage of battery and the battery icon are displaying the good value now
2. Alt always stays at zero in flight even if I tick the GPSAltMain box. "Cus6" contains an inconsistent data between 80 to 31000 sometime with a sign sometime not. The value is never related to the real altitude
3. dth displays the good value now and it's very usefull

So it stays only the last recalcitrant Alt.

Maybe one more : what is the central frame normally used for ? I don't understand the orientation of the internal line. It's moving but it doesn't follows the heading of the UAV or a line (vector) between the home position to its current position. It's not coherent.

Franck

Try the version I've just posted. It looks like the spreadsheet documentation I have for the Pixhawk data is wrong. I've used information from a LUA script I found.

The line in the central box is, I understand, the bearing FROM the aircraft to HOME.

Mike

Hi Mike,

All is running right now ! "Alt" gives the barometric altitude and I'm able to reset it with the contextual telemetry menu, it's great

Thanks a lot

Franck

installed the latest test version and it works well -- distance to home, ht above home, ht above sea level.
running arducopter on pixhawk
Mike, are you planning an updated "release" version of ersky9xr_rom.bin with all these new fixes?