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JPS6420747A - Two-wire type full duplex modulator-demodulator - Google Patents

Two-wire type full duplex modulator-demodulator

Info

Publication number
JPS6420747A
JPS6420747A JP17784787A JP17784787A JPS6420747A JP S6420747 A JPS6420747 A JP S6420747A JP 17784787 A JP17784787 A JP 17784787A JP 17784787 A JP17784787 A JP 17784787A JP S6420747 A JPS6420747 A JP S6420747A
Authority
JP
Japan
Prior art keywords
signal
modulator
demodulator
dial backup
full duplex
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
JP17784787A
Other languages
Japanese (ja)
Inventor
Hiroyuki Masuda
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
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 filed Critical NEC Corp
Priority to JP17784787A priority Critical patent/JPS6420747A/en
Publication of JPS6420747A publication Critical patent/JPS6420747A/en
Pending legal-status Critical Current

Links

Landscapes

  • Bidirectional Digital Transmission (AREA)

Abstract

PURPOSE:To automatically transfer a dial backup system at dial backup by using a transmission request signal (RS signal) so as to control a transmission enable signal (CS signal). CONSTITUTION:The RS signal controls the CS signal at data transmission and a special signal is sent when the RS signal is OFF and a special signal sent from an opposite modulator-demodulator and a start bit are detected at data reception. Since the same operation as the 4-wire full duplex modulator- demodulator is attained, one modulator-demodulator transmit/receive the 2/4-wire data and the number of modulator-demodulators prepared by dial backup is less. Moreover, the telephone number of the modulator-demodulator of opposite party is stored and the telephone number stored at the dial backup is dialed automatically thereby moving quickly to the dial backup system.
JP17784787A 1987-07-16 1987-07-16 Two-wire type full duplex modulator-demodulator Pending JPS6420747A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP17784787A JPS6420747A (en) 1987-07-16 1987-07-16 Two-wire type full duplex modulator-demodulator

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP17784787A JPS6420747A (en) 1987-07-16 1987-07-16 Two-wire type full duplex modulator-demodulator

Publications (1)

Publication Number Publication Date
JPS6420747A true JPS6420747A (en) 1989-01-24

Family

ID=16038147

Family Applications (1)

Application Number Title Priority Date Filing Date
JP17784787A Pending JPS6420747A (en) 1987-07-16 1987-07-16 Two-wire type full duplex modulator-demodulator

Country Status (1)

Country Link
JP (1) JPS6420747A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0438154U (en) * 1990-07-27 1992-03-31

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6251857A (en) * 1985-08-30 1987-03-06 Nec Corp Two-wire full duplex modem with cd transmission

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6251857A (en) * 1985-08-30 1987-03-06 Nec Corp Two-wire full duplex modem with cd transmission

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0438154U (en) * 1990-07-27 1992-03-31

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