What Is a Four-Wire Circuit?

4-Wire Circuit: It is a wiring scheme often used for asynchronous serial connection between a pair of computers. One pair of wires is used to transmit data in one direction and the other pair is used to transmit data in the opposite direction. Four-wire circuits are usually used for longer distances than three-wire circuits.

Four-wire circuit

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4-Wire Circuit: It is a wiring scheme often used for asynchronous serial connection between a pair of computers. One pair of wires is used to transmit data in one direction and the other pair is used to transmit data in the opposite direction. Four-wire circuits are usually used for longer distances than three-wire circuits.