PURPOSE: To allow automatic correction of shift in the rotation starting position occurred during intermittent rotational motion by holding the level. of an encoder signal for every arbitrary period and deciding the rotation starting position for every arbitrary period.

CONSTITUTION: When the rotation starting position of a stepping motor 11 is shifted from an original position due to an external cause, Q1 signal 20 from a flip-flop 5 is held at High level for an arbitrary period and a pulse B16 is delivered, as a correction drive pulse 22 to a stepping motor drive circuit 9 through an AND gate 7. When the motor 11 rotates to arrive at the original position, an encoder signal 13 makes transition from High to Low level and Q2 signal 18 of a flip-flop 6 goes Low through a differential circuit 4 thus stopping the stepping motor 11 at the original position. Intermittent rotational motion is then resumed, starting from the original position, by a rotation control pulse 23 delivered from an intermittent rotational motion control circuit 10.