| 摘要 |
<p>PURPOSE:To reduce the circuit scale by providing a counter means used selectively for a reference pulse generating means and a synchronization protection means with a selection signal. CONSTITUTION:A state transit counter 31 acts like a reference pulse generating means generating a reference pulse by a selection signal of a select signal generating circuit 41, a multi-frame pattern detection circuit 11 detects a multi- frame pattern in an input data to advance the counter 31 and when the counter counts up a prescribed number, a reference pulse is generated. On the other hand, a coincidence detection circuit 20 detects coincidence of the multi-frame pattern detection signal in the timing of the reference pulse and the counter 31 is switched by a selection signal of the select signal generating circuit 41 to act like a synchronization protection means and the counter counts the synchronization protection state.</p> |
