Radio Control setup - twitching channels

Blue Robotics Vehicles BlueBoat
1

I am currently setting up an RC to control our Blueboat. Using the FlySky ST8 and SR8 (it supports SBUS) ST8-SPECIFICATIONS | Flysky

What I have done so far:

So now, I should be able to perform the RC calibration in QGC.

In the channel monitor/attitude controls, I can actually see a respons to me moving the sticks of my RC.

The issue now is:

Every second or so, all the channels shortly shift/twitch to negative values (and then back). See the screenshots:

Normal:

grafik
grafik250×187 5.51 KB

Shifted:

grafik
grafik333×213 7.14 KB

Is this a known bug that I can ignore? Did I configure Serial1 wrong? Could there be some other issue?
I don’t think the RC is faulty as it is new and displays its own axis movements correctly. I have already updated to the newest QGC on Windows v5.0.8

Only thing that comes to mind is the SBUS failsafe bit, but I have checked and unchecked the corresponding setting in RC_OPTIONS (Ignore Receiver Failsafe bit), and the issue has remained.

2

Hi @jobotics -
You may want to try with QGC version 4.2.8 - Blue Robotics ceased testing versions later than that, so your issue could be connected to something in the new version?

3

QGC version not the root cause, unfortunately. I had been using the version recommended in the Blueboat software setup guide before: QGC installer from Software setup guide
And I only decided to try a newer version after I had encountered this issue in the older QGC version. The behavior is exactly the same in both QGC versions.

Could you please suggest steps to fix this issue?

4

QGC version not the root cause, unfortunately. I had been using the version recommended in the Blueboat software setup guide before: QGC installer from Software setup guide
And I only decided to try a newer version after I had encountered this issue in the older QGC version. The behavior is exactly the same in both QGC versions.

Could you please suggest steps to fix this issue?

Explicitly tried 4.2.8 now, issue remains the same. Could you please assit in fixing this? @tony-white

Update: If I turn the receiver (RF) off and on again via my transmitter (this is possible with my RC model), and sometimes randomly, the issue disappears for a minute or so and all the channels in QGC look normal. After some time the behavior described above reappears, however.

5

I have solved the issue. I hope someone else will find this useful as well:

The Navigator Documentation mentions a method of switching the RC input to non-inverted UART (IBUS protocol according to table). Luckily, our RC supports IBUS, too.

So, I cut the trace on the back of the board, connected the UART solder pad and – it actually works! No more twitching and the channels are still recognized.

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