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Hi

I would like to see the maximum altitude next to the current altitude on my telemetry screen.

In the telemetry settings I have Alt and VSpd values.
In the telemetry screen I can show Alt-, Alt and Alt+. I guess Alt+ is for the maximum altitude.
So I display the Alt+ value on the screen and apply a switch to reset Alt to zero along with the timers.

Here comes the problem:

• On my Taranis X-Lite Pro with a Graupner HoTT Falcon Receiver (internal Vario) the Alt+ value shows the altitude reached during the flight as expected (checked in comparison with the Alt value during flight)

• On my Radiomaster TX16S with different Graupner HoTT GR-16 Receivers (internal Vario) and different models the Alt+ value shows numbers that go in the thousands after one flight. Though when I reset Alt value, the display shows the same value vor Alt and Alt+.

Does anyone know why this occurs? And more so how I can get the Radiomaster to show the correct values?

Thank you for help.

Probably wrong values being sent somewhere, might be the different receiver, or that the firmware on the RF module you use on each radio being different and one having a bug around that. Start by checking / matching multiprotocol module firmware versions.

Hi Kilrah.

Thanks for the fast reply. I didn't receive the notification so I didn't see it...

I also thought at first that there might be wrong values being sent. But this seems implausible, since the Graupner Vario sends the Alt and VSpd values. I can display these on either TX perfectly.

The problem is the Alt+ value which is the maximum reached altitude. Alt+ is not coming from the RX or the Mutliprotocol Module, but it is calculated by OpenTX from the Alt values of the Vario. So if the Alt values are correct, but the Alt+ values are faulty, then the TX must have a bug somewhere in calculating the value. And since I get the bug one TX (Radiomaster TX16S) but not on the other TX (Taranis X-Lite Pro), I guess it must be the adaption for the TX16S that has the bug.

Do you agree with my analysis? What do I have to do? Can I correct this or should I open an issue somewhere?

Thanks

Alt+ isn't calculated from anything, it's simply the highest value that was received for Alt. If it's showing a wrong value then a spurious wrong value was received.

So Alt+ is max(Alt) - not 'calculated'. Ok. But the reading from Alt is perfect. I get normal readings like 109m.

But the Alt+ value then displays something like 2312m on the TX16S (see picture: https://www.dropbox.com/s/zo3escuv88nqc ... e.png?dl=0) and109m on the Taranis. Are you sure that must be the vario? I use Graupner RX with internal and external varios. None of them bring a nice Alt+ value on the TX16S...

123jhe wrote: ↑Thu Sep 02, 2021 7:07 pm But the reading from Alt is perfect.

It only takes one wrong received value that would last a split second and you would very likely miss, or possibly would not even last long enough to be logged or displayed.

Other protocols have a CRC that can weed out corrupted packets but I know nothing about how HoTT works or is implemented in the multi-based chain. But it should be the exact same telemetry code running on both radios OpenTX wise. You did not confirm the OpenTX and multi versions each was running though.

You are right. I didn't deliver the versions. What I will do is to update my radios from 2.3.11 to 2.3.14 and the multis as well. Then I will test the result and get back. This might take 1 or 2 weeks... Anyway, thank you this far.

Update: I did the version change on Radiomaster TX16S to 2.3.14 and the module to 1.3.3.0. After the update the value for Alt+ on the TX16S is working properly too.

Thank you for supporting me on the topic, Kilrah!