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INTERFACING: STEPPER MOTOR
22.2.4 | Generation of Half-Step
So far we have assumed that only one of four electromagnets is activated at a time. However, by alternately
activating a pair and then a single electromagnet, the step angle may be reduced to its half. Referring to
Fig. 22.5, with a starting condition of already activated coil 1, if in the next sequence coil 2 is activated without
turning off coil 1, then the pair of active electromagnets would attract the rotor simult-aneously, with equal
force. is would force the rotor to take a position, which must be equidistant from both electromagnets as
shown in Fig. 22.5(b). In the present ...