Patent · US Expired

Multipoint data communication system with collision detection

US4063220A · kind A · utility

324Cited by
10References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 31, 1975
Grant dateDec 13, 1977
Priority date
Expiry dateMar 31, 1995

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L12/413
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

Apparatus for enabling communications between two or more data processing stations comprising a communication cable arranged in branched segments including taps distributed thereover. Tied to each tap is a transceiver which on the other side connects to an associated interface stage. Each transceiver includes, in addition to the usual transmitter and receiver sections, a gate which compares the data from the interface stage with the data on the cable and indicates whether such are equal. Should such be unequal, an interference between the transceiver and the cable is indicated, disabling the associated transmitter section. Each interface stage tied to such transceiver also includes an input and an output buffer on the other end thereof interfacing with a using device, such input and output buffers storing both the incoming and outgoing data. The output buffer is connected to a clock-driven shift register which converts the buffered data to a serial stream, feeds such data to a phase encoder, which then connects to the transmitter or driver section of the transceiver. The input buffer is loaded by an input shift register which derives its clock from a phase decoder, the shift regist…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.