JPS5561165A - Electronic type key telephone unit - Google Patents

Electronic type key telephone unit

Info

Publication number
JPS5561165A
JPS5561165A JP13431178A JP13431178A JPS5561165A JP S5561165 A JPS5561165 A JP S5561165A JP 13431178 A JP13431178 A JP 13431178A JP 13431178 A JP13431178 A JP 13431178A JP S5561165 A JPS5561165 A JP S5561165A
Authority
JP
Japan
Prior art keywords
switches
switching state
state
circuits
cpu
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
JP13431178A
Other languages
Japanese (ja)
Inventor
Ryoichi Yabata
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 JP13431178A priority Critical patent/JPS5561165A/en
Publication of JPS5561165A publication Critical patent/JPS5561165A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/58—Arrangements providing connection between main exchange and sub-exchange or satellite
    • H04Q3/62—Arrangements providing connection between main exchange and sub-exchange or satellite for connecting to private branch exchanges

Abstract

PURPOSE:To make the switch into normal condition in a short time, by comparing the switching state of the switch of communication path with the memory content storing latest state and controlling the switching state of switch so that it is in agreement with the memory content. CONSTITUTION:The detection circuits 3 and 4 detecting the communication current are connected to the constant current circuits 1 and 2 feeding communication current to the telephone sets 5 and 6, and the circuits 3 and 4 detect the switching state of the audio switches S1-S4 connected to the line communication paths 10 and 11. The switching state of the switches S1-S4 detected by the circuits 3 and 4 is fed to CPU 7 and it is stored in the memory circuit connected to CPU 7. The CPU 7 compares the switching state of the switches S1-S4 with the content stored in the memory 8 and if not in agreement, control signal is fed to the switches S1- S4 to restore them to normal operation state. Thus, if the switches S1-S4 are in failure due to any cause, they can be restored to normal state in a short time.
JP13431178A 1978-10-31 1978-10-31 Electronic type key telephone unit Pending JPS5561165A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP13431178A JPS5561165A (en) 1978-10-31 1978-10-31 Electronic type key telephone unit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP13431178A JPS5561165A (en) 1978-10-31 1978-10-31 Electronic type key telephone unit

Publications (1)

Publication Number Publication Date
JPS5561165A true JPS5561165A (en) 1980-05-08

Family

ID=15125321

Family Applications (1)

Application Number Title Priority Date Filing Date
JP13431178A Pending JPS5561165A (en) 1978-10-31 1978-10-31 Electronic type key telephone unit

Country Status (1)

Country Link
JP (1) JPS5561165A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63171097A (en) * 1987-01-08 1988-07-14 Matsushita Electric Ind Co Ltd Telephone exchange
JPH0610312U (en) * 1992-07-09 1994-02-08 政博 柏田 Anti-vibration gloves

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63171097A (en) * 1987-01-08 1988-07-14 Matsushita Electric Ind Co Ltd Telephone exchange
JPH0610312U (en) * 1992-07-09 1994-02-08 政博 柏田 Anti-vibration gloves

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