Fiber-optical dual ring redundancy controller for controller local area network

Abstract

The invention discloses an optical fibre bicyclo redundancy controller for controlling local area network, comprising a major ring signal selector, a minor ring signal selector, a major signal repeater and a clock generator, wherein the controller is linked between a CAN interface, a major-minor ring optical fibre receptor and a major-minor ring optical fibre sender as a transmitting-receiving unit of the CAN node, the functions of the major signal selector and the minor signal selector are to dynamically forming an optical fibre working loop, the function of the major ring signal repeater is to realize a signal transfer between the CAN node and the optical fibre loop, and the clock generator is designed to provide a clock signal acquired by the operation of the circuit.

Description

technical field [0001] The invention belongs to the field of computer field bus peripheral equipment, in particular, the invention relates to an optical fiber double-ring redundant controller applied to a controller area network (CAN). Background technique [0002] Controller Area Network (CAN for short) is a field bus standard proposed by the German Bosch company in 1986, and became the ISO11898 international standard in 1993. CAN is used in industrial control fields such as automobiles, electric power, machinery, and chemicals It has been widely used and has become one of the mainstream technologies of industrial digital communication. [0003] At present, most CAN networks in the world use twisted-pair wires as the transmission medium. Twisted pair has the advantages of low price and strong anti-interference ability. However, in some occasions with strong electromagnetic interference, the reliability of communication cannot be guaranteed, and the transmission distance o...

AI Technical Summary

Problems solved by technology

However, when the star coupler fails, the entire system will collapse. Another disadvantage of the star structure is that it is not convenient for fiber optic wiring.

[0005] In order to overcome the above shortcomings, a ring structure can be considered, but the signal delay of the ring structure is relatively large, and the single ring structure is not reliable enough, so a double ring redundant structure is required

CAN is an asynchronous communication protocol and cannot use the double-ring redundancy strategy adopted in the data communication network.

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