G30 command failed --could use some input

[jamiek (Jamie)]

Check if you are using Z_MIN_PROBE_USES_Z_MIN_ENDSTOP_PIN

If you are using the same zmin and probe, you must disable it (which seems backwards).

I searched some of my older posts when I knew more, which I have since forgotten:

G38 Probe Target implementation

With the latest firmware (Ryan updated a couple weeks ago) it is possible to get this working with just Configuration.h and Configuration_adv.h, no changes to any cpp files are necessary. There does appear to (still) be some weirdness around Z_MIN_PROBE_USES_Z_MIN_ENDSTOP_PIN, and as far as I know this must be disabled (even if using the zmin connector on the board). My configuration (including other stuff specific to my machine) has G38 working and is outlined here: https://www.v1engineering.…

Using ZMIN input for the Z_PROBE for G38

This is similar to my experience, in particular Z_MIN_PROBE_USES_Z_MIN_ENDSTOP_PIN is bad. It does not work for G38 on the zmin pin as the name would imply, and you have to disable that option and manually set probe to the ZMIN pin, which seems backwards. Marlin is internally confused about probing, I think because the history is around bed leveling and not the CNC use case of G38 style probing.