摘要 |
<p>A shift register is described particularly adapted for selectively controlling the energization of the windings of a stepping motor so as to provide selective overlapping phase energization. The shift register consists of four stages each having master and slave sections with each stage controlling the energization of an associated motor winding. A shift register control unit, responsive to stepping and directional signals, directs the shifting of information between the various stages of the shift register. In response to a step high input signal, a high level of one shift register stage is shifted in a selected direction to the adjacent stage with both stages directing the energization of their respective motor windings. Similarly, in response to a step low signal the low levels of the shift register stages are shifted in a selected direction to their adjacent stages causing the deenergization of the respective motor windings. Step high and step low signals are applied simultaneously to cause the output of each shift register stage to shift its level to the adjacent stage in the selected direction.</p> |