QGC 4.0 - removed channel 8 RSC

In the latest version of firmware (arducopter trad heli), with the latest QGC there is no longer an option to set channel 8 to throttle output so I cannot tie throttle output to a knob. This is how I normally fly, I arm, and raise the throttle (with collective pitch at zero) using a knob I programmed into my radio as channel 8. This allows me to have a constant speed at any pitch and is the only way I fly 3d in acro mode. This allows me to adjust the throttle speed at will but its no longer in the menu for “heli”. I had to roll back to QGC 3.5.6 and it returned, but I had to re-flash the older firmware (arducopter-heli-stable-3.6.12) manually as ver 4 had tons of missing parameters. I do not like manually flashing firmware, I prefer to have QGC find the right fmuv2 version firmware on its own and flash it as its safer than manual updates.

Is there any reason for this change and I missed the note somewhere? I cannot use arducopter without this ability and I tried to map it through the full param list but it didnt work. I left it on the older QGC and older firmware but ideally I would like to use the latest version.

Below is the version I am forced to use with the latest QGC and the missing option in ver4:

Thanks in advance and let me know if this is already known and being worked on or if I should report it as a bug somewhere (but where)? I am fine now because both my T-Rex 600 Pro DFC and T-Rex 700 DFC are both using the older firmware (which has the option enabled so all works fine) but I am on the older firmware (3.6.12 and QGC 3.5.6) so I am not on the latest builds of either but would like to be ideally.

NOTE, I now realize that my second picture shows FMUv3 (thats my 700 and was used to show the older firmware RSC channel 8 knob option), my T-Rex 600 Pro uses FMUv2 so thats all accurate.

FYI: QGC uses the param meta data from H_RSC_MODE for this combo box. Which is currently this:

<value code="1">RC Passthrough</value>
<value code=" 2">External Gov SetPoint</value>
<value code=" 3">Throttle Curve</value>
<value code=" 4">Governor</value>

You will find some answers here: Arducopter 4.0 Heli Testing Thread

1 Like

I read through that originally before posting the question but I didn’t see anything specific to the channel 8 throttle.

Rc8 input was changed to RC passthrough. I explained more in the thread Fred provided.

I read that through but I didn’t get it, so maybe a better question would be to ask what needs to be changed to make it work? I originally set it to passthrough to test the same radio config (channel 8 set to knob) as I had set it my radio for the previous firmware and it didn’t work. I’m fine with leaving the older firmware on there if that’s the only way to get it working but I’d prefer to use the latest firmware.

Here is a link to Tradheli 4.0 summary of changes post