| 摘要 |
<p>In a telephone exchange apparatus which accommodates digital communication lines, and employs a slave synchronization system in which a clock is extracted from a signal received from the network. and an exchange switch is operated in synchronism with the extracted clock so as to prevent data omission caused by a difference between operation frequencies of a network and an exchange apparatus, if there is a phase difference between a pre-switching clock and a post-switching clock when the extracted clocks are switched upon changing of communication lines, the post-switching clock is delayed by the phase difference between the two clocks so as to cause the phase of the post-switching clock to coincide with the phase of the pre-switching clock.</p> |
