Everything about micrometers!

To check to see if the micrometer can move from one end to the next, you move the micrometer by (Cal Step) + (Zero position).
Examples: If (Cal Step)+(Zero Position) = x

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>M,10,-x
 - This will move the micrometer towards the mirror
>M,10,x+1
>M,10,-1
 - Type the absolute value for the movements (x-1, ie x=2121 --> 2121 +1 = 2122)
 - This will move the micrometer back to the measuring position, the -1 will reset the zero location

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>M,10,x
 - This will move the micrometer towards the mirror
>M,10,0
 - This will move the micrometer back to the measuring position

Refer to Motor Positions for the motor numbers

Micrometer Optical LED Reference Trigger
Finding the Micrometer
micrometer_optical_led_reference_triggering.pdf - Includes the Schmitt Trigger schematics.