I’m relatively new to the Pixhawk flight stack and firmware in general, but my question relates to this. According to Mixing and Actuators | PX4 User Guide, you can change the mixer via SD card directory. I’m wondering if you can do the same for .toml geometry files to change which motor is controlled by which signal. Furthermore, I’m looking to create a .aux.mix file for coax octo so that the bottom 4 are controlled by aux1-4 instead of main5-8.
More concretely, is it valid to just create a .toml file with a given key and ordering of rotors and use that key for a mixer file? Would the parsers and other machinery work by just doing that? I assume no for the coax octo case; I think you’d need to specify somewhere that the coax octo needs a .aux.mix file in addition to a .main.mix.
This is probably the most obvious question, can you just bypass the SD card stuff by making the edits via Building PX4 Software | PX4 User Guide or would that risk using an unstable build (is there any way to git clone a stable build)?
Update: From what I understand, changing the appropriate file here PX4-Autopilot/ROMFS/px4fmu_common/init.d/airframes at master · PX4/PX4-Autopilot (github.com) to set appropriate MIXER_AUX for bottom octo coax and appropriate PWM_AUX_OUT, in addition to creating a new .toml file for the bottom rotor config and referencing its key in a new appropriately-named .aux.mix file should produce the desired result. Again, not completely sure if all the machinery works in between.