I have been reading it, somewhere in the Klipper docs, but I can’t find it right now.
Klipper is pretty “picky” with G28.
Like How to go out of print area for tool change? - #16 by DanS (last quote) you may probably ask @Sineos to answer your question correct
Thanks for believing that I know everything, but unfortunately my knowledge about Klipper’s homing process is very basic and I do not know if anything is reset or if only the axes are “zeroed”
TBH never bothered but since @EddyMI3D brought it up, it is an interesting question
That’s a bit of a “tricky question” as G28 is one of those arcane g-code commands that isn’t particularly well defined.
In practice, the command is used to establish the actual X, Y, and Z positions of the toolhead. That is, the software internally tracks where the toolhead is, and it updates that internal position when ever it moves the toolhead to a new position. But when the machine is first powered on the software doesn’t know the actual X Y and Z position, so one “homes the printer” to establish that information.
Thus the G28 doesn’t really “reset” anything - it just moves the toolhead to a position that has a “known” position.
Moving the toolhead to a known position (typically carriage positions just next to the endstop switches) may undo a calibration by Z_TILT_ADJUST or QUAD_GANTRY_LEVEL. Those tools alter the Z carriage positions to better align them relative to the bed, while “homing” aligns the carriages to their endstops. So, “homing” can in effect undo the impact of those tools - it isn’t “resetting” them in a software sense though.
