Telephone exchange apparatus with communication line clocking
First Claim
1. A telephone exchange apparatus comprising:
- connection means for connecting a plurality of communication lines;
exchange means for exchanging communication between the plurality of communication lines and a plurality of telephone sets;
selection means for selecting one of the plurality of communication lines; and
providing means for providing clocks from said one of the communication lines selected by said selection means to said exchange means,wherein said selection means does not select another one of the plurality of communication lines once said one of the plurality of communication lines has been selected until a communication via said one of the plurality of communication lines ends.
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Accused Products
Abstract
In a telephone exchange apparatus which accommodates digital communication liens and employs a slave synchronization system in which a clock is extracted from a signal received from the network, an exchange switch is operated in synchronism with the extracted clock so as to prevent data omission caused by a difference between operating 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 communication lines, the postswitching 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.
23 Citations
9 Claims
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1. A telephone exchange apparatus comprising:
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connection means for connecting a plurality of communication lines; exchange means for exchanging communication between the plurality of communication lines and a plurality of telephone sets; selection means for selecting one of the plurality of communication lines; and providing means for providing clocks from said one of the communication lines selected by said selection means to said exchange means, wherein said selection means does not select another one of the plurality of communication lines once said one of the plurality of communication lines has been selected until a communication via said one of the plurality of communication lines ends. - View Dependent Claims (2, 3)
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4. A telephone exchange apparatus comprising:
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connection means for connecting a plurality of communication lines; exchange means for exchanging communication between the plurality of communication lines and a plurality of telephone sets; selection means for selecting a first communication line having first clocks from the plurality of communication lines; control means for controlling said selection means so as to select a second communication line having second clocks from the plurality of communication lines; delay means coupled to said selected first and second communication liens for delaying the second clocks from the second communication line by a phase difference between the first clocks form the first communication line and the second clocks from the second communication line; and providing means for providing the first clocks from the first communication line or the second clocks delayed by said delay means to said exchange means. - View Dependent Claims (5, 6, 7, 8, 9)
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Specification