Shared 485 circuit and control method

Abstract

The invention discloses a shared 485 circuit which comprises a 485 communication module, a first single-chip microcomputer, a second single-chip microcomputer and a logic or OR operation module. The 485 communication module is connected with the first single-chip microcomputer and the second single-chip microcomputer. The first single-chip microcomputer and the second single-chip microcomputer are connected through a first communication state line and a second communication state line. A TX port of the 485 communication module is respectively connected to an RX port of the first single chip microcomputer and an RX port of the second single chip microcomputer, and an RX port of the 485 communication module is respectively connected to a TX port of the first single chip microcomputer and a TX port of the second single chip microcomputer; an enable signal EN1 port of the first single-chip microcomputer and an enable signal EN2 port of the second single-chip microcomputer are connected with the output end of the logic or OR operation module, and a port and a DE port of the 485 communication module are connected with the input end of the logic or OR operation module. According to the invention, through the circuit design of sharing 485, the sharing of the 485 module is realized, the hardware cost can be saved, and the plate manufacturing space is reduced.

Description

technical field [0001] The invention relates to the technical field of RS485 communication, in particular to a shared 485 circuit and a control method. Background technique [0002] In the field of industrial control, there is often a need to drive multiple groups of motors with a miniaturized controller, which inevitably requires integrating multiple single-chip microcomputers into one controller. The common practice is: use 485 sharers to solve multiple When two 485 hosts coexist in the same RS-485 bus network, the RS-485 bus supports a multi-slave communication mode, and the priority principle or the first-come-first-served principle set by it is used to ensure that the conflict of the 485 bus will not affect the entire bus. The communication fails, but the 485 sharer can only partially solve the 485 communication conflict problem caused by the coexistence of multiple hosts. Or design the 485 communication modules separately and connect them to the single-chip microcompu...

AI Technical Summary

Problems solved by technology

[0003] The present invention provides a shared 485 circuit and control method to solve the problem of information transmission conflicts in the 485 communication process in the prior art

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