| 摘要 |
<p>PURPOSE:To prevent the erroneous recognition when one frame synchronizing signal detection is missed and to stabilize an action by enlarging the number of steps at a multi-frame mode. CONSTITUTION:A multi-frame instruction signal generating means 32 classifies a multi-frame from a single frame, outputs an instruction signal, a step number variable forward protecting means 33 makes variable the number of forward protecting steps with the instruction signal, and at the time of a single frame, (j) steps are obtained and at the time of the multi-frame, a (k) step more than the (j) times is obtained. Thus, since the number of forward protecting steps is made into k(>j) steps at the multi-frame mode, at the time of the multi-frame, even when one frame synchronizing signal detection is missed due to some reason regardless of the fact that a frame synchronizing signal is present inherently, a (j) times frame synchronizing signal is not detected like the time of a single frame, and the erroneous recognition that it is a pull out is eliminated.</p> |
