channels 5 and 6 dont work over the usb trainer cable

[fuzzbuzzbay999]

I know this is probably a well known issue, but couldn't find any info on why it is a thing, as the original firmware didn't have this issue

--some background--
When the transmitter is plugged into a windows pc, using the trainer, any input mapped to channels 5 and 6 will not affect the Z rotation or sliders, however channels 7 and 8 work

To Reproduce
Steps to reproduce the behavior:

1. plug the transmitter in and connect
2. open "setup usb game controller"

whatever is bound to 5 and 6 will not do anything

General information

• OpenTX version 1.6.0 (6/2/2022)
• FS I6X
• windows 10

[ajjjjjjjj]

Yes, it's a workaround for USB HID issue i had, those are remapped 3 -> 5. This probably could be done better, like using further channel, but it would still be a workaround.

My suspection is that USB Joystick issues are caused by old and probably buggy lib, i have reviewed my code around this many times and haven't found an issue. This most probably can be solved by moving to newer library version, but interface has changed a little bit therefore it needs some work.

If someone is willing to work on this i'm willing to help with my knowledge around this.

[fuzzbuzzbay999]

What lib is currently being used to create and send the gamepad signals?

[ajjjjjjjj]

Currently it is using STM32F0x2_USB-FS-Device_Lib_V1.0.0

[fuzzbuzzbay999]

"radio" is the files used to translate openTX to i6x hardware, and, "companion" is raw openTX.
Is that correct?

[ajjjjjjjj]

radio/src contains "everything":

• targets/ - code specific to board, ie.: taranis and its variations, and of course flysky,
• targets/common - files common to platform, like stm32 variations: F0, F2, F4,
• thirdparty/ - libraries

USB specific code is in targets/common/stm32.
You may also check git history and search for "usb" to see how it was added.
Contact me on discord directly if you want.

[fuzzbuzzbay999]

okay, so i think i have a solution, if the button count was to be shrunk from 16 to 12, to maybe "open up" the data line, to possibly avoid what could be a buffer overflow, or the mcu isnt getting enough clock times to fully send out all 24 channels?
It is certainly weird though

[fuzzbuzzbay999]

Dont know how to word it, but i did knotice only the first 16 indexes of the HID_Buffer were being processed and sent, so maybe changing the button count wouldn't help

[ajjjjjjjj]

Have fun experimenting on that :) I have remapped one of the channels because sending anything other than 0 at that byte (or some of the bits only, i don't remember exactly) causes complete mess on output data.

[Revenger]

Any updates on this as I am setting it up to use in sims and not having channels 5-6 is slightly annoying.

[EnTune926]

Any updates on this as I am setting it up to use in sims and not having channels 5-6 is slightly annoying.

I would also like to know if any progress has been made here.

[ajjjjjjjj]

Fixed by #424