MS2000 or RM2000 syntax

Format	UM [axis]= ### …
Units	integer
Remembered	Using SS Z

Tiger syntax

Format	UM [axis]= ### …
Units	integer
Type	Axis-Specific
Remembered	Using [addr#]SS Z

Specifies the multiplier for most serial commands such as MOVE and WHERE. Default for stages is 10000, which means 10000 units per millimeter or 0.1μm/count. For rotary stages and micro-mirror devices the UM is 1000 corresponding to milli-degrees.

The sign of the Unit Multiplier can be used to change the relative direction of motion for commanded moves, but using the CCA Z command is the recommended method for changing the stage direction. The Unit Multiplier can be saved with the SS Z command.

If there are no errors, a positive reply of :A is returned.

UM command has no effect if the axis is a Clocked Device like Filter Slider , Objective slider or Objective Turret.

As of Firmware version 9.2l (for MS2000) and 3.18 (for Tiger) , when UM for a clocked Device is set to “1” , Where command prints the Axis position in millimeters instead of slot position. Move command continues to work, while Relative move doesn't. This feature is mean for troubleshoot and diagnostic usage only and not meant for regular operation.