A stepper motor is an electromechanical
device which converts electrical pulses into
discrete mechanical movements. The shaft
or spindle of a stepper motor rotates in
discrete step increments when electrical
command pulses are applied to it in the
proper sequence. The motors rotation has
several direct relationships to these applied
input pulses. The sequence of the applied
pulses is directly related to the direction of
motor shafts rotation. The speed of the
motor shafts rotation is directly related to
the frequency of the input pulses and the
length of rotation is directly related to the
number of input pulses applied.

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