To control stepping motors, the balance bridge power drive circuit is made up by TDA1521 integrated audio power amplifier, the pulse allotter is made up by the parallel ports of computer and latches.

双回转构的步进电控制电路TDA1521集成功率放大器组成平桥式功率驱动电路，计行口经过锁存器构成脉冲分配器。