The Sync Move Absolute is intended for commanding multiple axes to move simultaneously. The moves will be ratioed such that they will arrive to the commanded positions simultaneously, even if the distances are different. The Gear Absolute is intended to be used when one axis must follow another axis.
Usually, if it’s possible to use the Sync Move, that is preferred. In all other cases, use the Gear Absolute. With the Gear Absolute, if there is an option of following a target position rather than an actual position, do that, since actual positions are noisy, whereas target positions are smoother.
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