SBUS does not output AUX channels

Hi all, I’m currently trying to send the AUX signals through SBUS on my Cube Orange. According to the Cube Orange docs, the PX4 IO chip processes the MAIN channels and enables the output through SBUS. The AUX outputs are processed by the FMU and the docs indicate, that they will only be sent through PWM.

However, I wonder if it is indeed an hardware limitation or if the AUX signals can somehow still be sent through the SBUS channel. Do you guys have the same issue using other boards? I have read some similar threads on this forum where some tried to send more than 8 signals through SBUS, since PX4 limits (or has limited) the number of SBUS channels to 8. Does anyone have an idea how to solve this?

In my setup, the 8 MAIN channels and AUX 1 actuate engines with ESCs, and the other 5 AUX channels actuate servo motors. Thanks in advance.

Can you describe the settings under QGC - Px4 about having mapped AUX 1 with a servo.

Sorry, my description or the words that I am using might be confusing. So the problem does not lie in QGC. What I mean is that the AUX signals that are produces through the AUX mixer cannot be sent through the SBUS port. The AUX mixer processes the control inputs from control group 0 (flight control) and I want the AUX signals to be sent through SBUS.

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I am actually running into the exact same issue on a pixhawk 4. In my config, the control surfaces are controlled via sbus ch1-8 (MAIN1-8), and i was hoping to control motors on sbus ch9-16 via the aux(1-8) but I cant get sbus to output on the aux rail, the aux rail is only outputting PWM. I really hope there is a fix for this!

There are some attempts to change the number of outputs in PX4 for SBUS, like Commits · OskarPepryk/Firmware · GitHub, which is running on an older version of PX4. I personally didn’t try it yet. I think it might also be an hardware issue, since the Cube Orange, for example, indicates that only the 8 MAIN OUT channels processed by the IO chip are sent through the SBUS port. Which board are you using?

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Im using a pixhawk 4. Why would they ever architect things like this?

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Can you advice how can you output pwm signals on the Aux 1 channel . i am also using the orange cube and am not able to figure out .

thank you