摘要 |
The invention provides a synchronous circuit which prevents occurrence of a step-out condition even when an error in padding occurs. The synchronous circuit is applied to a digital transmission system wherein the number of bits in a frame varies periodically and bit number information is included in a frame. Making use of the fact that the bit number information has a periodicity, bit number information for one period is generated by a padding bit generator (44) based on information from a synchronism detector (42) to prevent occurrence of a step-out condition caused by an error in received bit number information. <MATH> |