Hello to the forum!
I have rooted my “Creality K1 Max” and installed the components “Moonraker” and “Fluid” user interface to use Klipper and some hidden features of this printer and to use third party hardware upgrades to increase the quality of the printed pieces.
So I have bought a new extruder and a filament sensor to replace the original Creality parts:
- “LDO Orbiter V2.0” extruder
- “LDO Orbiter Filament Sensor”
(both are supported by Klipper)
The installation and wiring of the extruder and mounting of the the filament sensor will be no problem (there are a lot of very good tutorials and adaptor models), the wiring of the filament sensor will 
Because in contrast to the original filament sensor, the “LDO Orbiter Filament Sensor” has four cables instead of three:
The fourth cable belongs to a button that can be used to start the script for unloading the filament. And this is where my “problem” begins:
According to the installation instructions, I need a free/unused “input” pin on the controller board (spare pin headers) or unused expander board connections and its designation in order to be able to use this button. I need the designation for a “Klipper” configuration file (more details can be found at LDO Orbiter filament sensor under section “3.2 Configuration for Klipper”).
Can someone in this forum help me? I’ve contacted Crealities customer support but they didn’t even understand my problem and asked for more information on my printer and a video or some photoes of the malfunction…
Kind regards
“Klaus”