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| Signal level comparing circuit |
| It is accordingly an object of this invention to provide a signal level comparing circuit which can ... |
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| Circuit arrangement for correcting slip errors in pcm receivers |
| I claim: 1. In a receiver for binary code words including information bits and redundancy bits to ... |
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| Redundant clock system utilizing nonsynchronous oscillators |
| In accordance with the present invention, there is provided a clock system with two nonsynchronized ... |
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Unit switching apparatus with failure detection
| Details |
Inventors: Soga, Kenji;
Assignee: NEC Corporation (Tokyo, JP)
Primary Examiner: Horabik; Michael
Assistant Examiner: Wilson, Jr.; William H.
Attorney, Agent or Firm: Foley & Lardner
A unit switching apparatus includes first and second current units, a spare unit, and a switching unit. Each of the current units includes a communication circuit for performing communication in accordance with set operation mode data and a failure detection circuit for detecting and notifying occurrence of a failure in the communication circuit. The spare unit includes a communication circuit for performing communication in accordance with set operation mode data, a memory for separately storing the operation mode data set in the communication circuits of the current units, and a CPU for, when the occurrence of the failure is notified by the failure detection circuit, reading out the operation mode data corresponding to the faulty current unit from the memory, and setting the data in the communication circuit. The switching unit switches the faulty current unit to the spare unit when the occurrence of the failure is notified by the failure detection circuit. |
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DETAILED DESCRIPTION It is an object of the present invention to provide a unit switching apparatus which can set a spare unit with the same setting as that of a faulty current unit within a short period of time.
In order to achieve the above object, according to the present invention, there is provided a unit switching apparatus comprising a plurality of first communication units of a current system, each of the first communication units including first communication means for performing communication in accordance with a set operation mode data and failure detection means for detecting and notifying an occurrence of a failure in the first communication means, a second communication unit of a spare system including second communication means for performing communication in accordance with a set operation mode data, storage means for separately storing the set operation mode data of the first communication means of the first communication units, and setting control means for, when the occurrence of the failure is notified by the failure detection means, reading out the set operation mode data corresponding to the faulty first communication unit from the storage means, and setting the set operation mode data in the second communication means, and unit switching means for switching the faulty first communication unit to the second communication unit when the occurrence of the failure is notified by the failure detection means.
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Fault Detection 
