JPS56122297A - Clock source automatic switching system - Google Patents

Clock source automatic switching system

Info

Publication number
JPS56122297A
JPS56122297A JP2542180A JP2542180A JPS56122297A JP S56122297 A JPS56122297 A JP S56122297A JP 2542180 A JP2542180 A JP 2542180A JP 2542180 A JP2542180 A JP 2542180A JP S56122297 A JPS56122297 A JP S56122297A
Authority
JP
Japan
Prior art keywords
clock source
register
designation register
automatic switching
designation
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP2542180A
Other languages
Japanese (ja)
Inventor
Masahiro Takahara
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
Nippon Electric Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NEC Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP2542180A priority Critical patent/JPS56122297A/en
Publication of JPS56122297A publication Critical patent/JPS56122297A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/04—Selecting arrangements for multiplex systems for time-division multiplexing

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Exchange Systems With Centralized Control (AREA)
  • Use Of Switch Circuits For Exchanges And Methods Of Control Of Multiplex Exchanges (AREA)

Abstract

PURPOSE:To obtain a clock source automatic switching system with reliability improved, by giving the double constitution to the clock source switching circuit. CONSTITUTION:The clock source switching circuit is made double, and contents of clock source designation register 4 of its own system and contents of clock source designation register 4 of the other system are collated by register collating circuit 6, and normalcy of clock source designation register 4 of its own system is monitored by register control circuit 5; and when clock source designation register 4 of its own system becomes faulty, clock source designation register 4 of its own system is inhibited from being selected in clock source designation register selecting circuits 7 of both systems, and register control circuit 5 of the other system is inhibited from operating to change contents of designation registers 4 of both systems, and thus, the clock source automatic switching circuit of the other system performs the switching operation of clock source 1 preferentially when designation register 4 of one system becomes faulty.
JP2542180A 1980-02-29 1980-02-29 Clock source automatic switching system Pending JPS56122297A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2542180A JPS56122297A (en) 1980-02-29 1980-02-29 Clock source automatic switching system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2542180A JPS56122297A (en) 1980-02-29 1980-02-29 Clock source automatic switching system

Publications (1)

Publication Number Publication Date
JPS56122297A true JPS56122297A (en) 1981-09-25

Family

ID=12165481

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2542180A Pending JPS56122297A (en) 1980-02-29 1980-02-29 Clock source automatic switching system

Country Status (1)

Country Link
JP (1) JPS56122297A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58129622A (en) * 1982-01-22 1983-08-02 ロ−ベルト・ボツシユ・ゲゼルシヤフト・ミツト・ベシユレンクテル・ハフツング Syncronizer for clock control type data processor
JPH03101416A (en) * 1989-09-14 1991-04-26 Nec Corp Clock supply switching circuit

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58129622A (en) * 1982-01-22 1983-08-02 ロ−ベルト・ボツシユ・ゲゼルシヤフト・ミツト・ベシユレンクテル・ハフツング Syncronizer for clock control type data processor
JPH03101416A (en) * 1989-09-14 1991-04-26 Nec Corp Clock supply switching circuit

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