JPS6444655A - Data communication system - Google Patents

Data communication system

Info

Publication number
JPS6444655A
JPS6444655A JP62202083A JP20208387A JPS6444655A JP S6444655 A JPS6444655 A JP S6444655A JP 62202083 A JP62202083 A JP 62202083A JP 20208387 A JP20208387 A JP 20208387A JP S6444655 A JPS6444655 A JP S6444655A
Authority
JP
Japan
Prior art keywords
data
signal
response signal
outputted
comparators
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
JP62202083A
Other languages
Japanese (ja)
Inventor
Junichi Suzuki
Hisataka Fujii
Toshiro Mise
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.)
Panasonic Electric Works Co Ltd
Original Assignee
Matsushita Electric Works 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 Matsushita Electric Works Ltd filed Critical Matsushita Electric Works Ltd
Priority to JP62202083A priority Critical patent/JPS6444655A/en
Publication of JPS6444655A publication Critical patent/JPS6444655A/en
Pending legal-status Critical Current

Links

Landscapes

  • Detection And Prevention Of Errors In Transmission (AREA)
  • Bidirectional Digital Transmission (AREA)
  • Communication Control (AREA)

Abstract

PURPOSE:To improve the data transmission efficiency by dividing data to be transmitted into blocks, inserting dummy data between block data to transmit data and transmitting a response signal from a data reception-side terminal equipment during transmission of dummy data. CONSTITUTION:Though a data signal VA' in the low level leaked to the four- wire reception side is outputted during data transmission, outputs of comparators 15a and 15b go to the low level and the detection signal of a response signal VB is not outputted if a reference voltage VS is set to a high value. Meanwhile, when the response signal VS is received, the level of the signal passing band-pass filters 13a and 13b is considerably raised and the detection signal of the response signal VB is outputted. The reference voltage VS of comparators 15a and 15b is properly set to eliminate a need of a signal processing circuit like an echo canceller which is used to prevent leak in a hybrid circuit 12, and the circuit constitution is simplified.
JP62202083A 1987-08-13 1987-08-13 Data communication system Pending JPS6444655A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP62202083A JPS6444655A (en) 1987-08-13 1987-08-13 Data communication system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP62202083A JPS6444655A (en) 1987-08-13 1987-08-13 Data communication system

Publications (1)

Publication Number Publication Date
JPS6444655A true JPS6444655A (en) 1989-02-17

Family

ID=16451681

Family Applications (1)

Application Number Title Priority Date Filing Date
JP62202083A Pending JPS6444655A (en) 1987-08-13 1987-08-13 Data communication system

Country Status (1)

Country Link
JP (1) JPS6444655A (en)

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