Previously drive resolution was determined using the SU? command, which returns the encoder resolution.
The SU? value is not meaningful when open-loop steppers are used, and cannot even be set in the controller.
Use the ZB? command to see if stepper positioning is enabled and encoder feedback is disabled.
If so the full-step (FR?) and microstep (QS?) values are used to determine drive_resolution.
If not then SU? is used to determine drive resolution, as previously.
Mark Rivers
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