CN102684923A

CN102684923A - Self-healing networking method for half-duplex asynchronous communication

Info

Publication number: CN102684923A
Application number: CN201210163930XA
Authority: CN
Inventors: 徐魁; 蒋瑀瀛
Original assignee: JIANGSU HUADE ELECTRIC POWER TECHNOLOGY Co Ltd
Current assignee: JIANGSU HUADE ELECTRIC POWER TECHNOLOGY Co Ltd
Priority date: 2012-05-24
Filing date: 2012-05-24
Publication date: 2012-09-19

Abstract

The invention provides a self-healing networking method for half-duplex asynchronous communication. The self-healing networking method comprises the following steps: firstly, a node in a network competes to become a host in a circular roll call mode; when a node smaller than the ID (Identity) of the network node is received and a roll call message is sent by the network node, the network node is converted into a slave; if only slave response is received after one round of roll call and no other completion roll calls are in the presence, the slave becomes the host; a status inquiry message (or practically required application message) is circularly sent to all slaves by the host; the slaves which do not respond three times continuously are rejected from a network; at the end of each polling, a new inquired node message is sent; if the host finds that the ID of the host is bigger than the ID of the new node, the host is converted into the slave; and otherwise, the new node is added to a slave list. Therefore, according to the self-healing networking method, the concept that the host and the slave must be appointed for avoiding conflict caused by sending messages by multiple nodes in the traditional half-duplex asynchronous communication network is cancelled. In addition, nodes can be flexibly added and deleted in the network without affecting normal networking application.

Description

A kind of half-duplex asynchronous communication self-healing network-building method

Technical field

The present invention relates to a kind of data communication field, more specifically, relate to the self-healing network-building method under the half-duplex asynchronous communication condition.

Background technology

Half-duplex asynchronous communication bus is by the widely used data communication bus of each research and development institution, and it often is applied between centralized control hinge and the decentralized control unit, because in the real application systems; The decentralized control element number is more; Receive the restriction of asynchronous communication, node can not be received and dispatched message simultaneously, can not have two or more nodes to send message simultaneously; Must specify a host node (main frame); Let host node successively question and answer realize mutual communication from node, if cause the host node fault to reassign like this, otherwise maybe network failure.

Therefore, need a kind of new network-building method to solve the problem that exists in the prior art.

Summary of the invention

Goal of the invention: technical problem to be solved by this invention is the deficiency to prior art, and the self-healing network-building method under a kind of half-duplex asynchronous communication condition is provided.

In order to solve the problems of the technologies described above, the invention discloses a kind of half-duplex asynchronous communication self-healing network-building method, may further comprise the steps:

Step 1, node are sent roll-call message competition hosted, roll-call order 1 ~ N, and N is the communication network maximum node number; Can set random delay before sending, the message of avoiding calling the roll sends conflict.

Step 2 call the roll to receive: receive that the node littler than own ID sends the roll-call message and transfer slave to, set up all slave lists, if one takes turns to call the roll and only receives that slave responds then transfers main frame to.

Step 3, main frame is to all slave circulation transmit status query messages or use message.

Step 4, main frame is not received the slave response continuous n time, then from communication network, rejects this node; N is a set point, generally is set at 1 ~ 6.

Step 5, main frame are sent inquiry new node message.

Step 6, bigger then transfer slave to if main frame is found own ID than new node, otherwise add new node to slave list.

The node ID information and the roll-call id information that comprise node self in the roll-call message in the step 1 of the present invention.

The node ID information and the poll node ID information that comprise node self in the status poll message in the step 3 of the present invention.

Inquiry new node message in the step 5 of the present invention comprises all present node id informations.

Among the present invention,, return step 1 again if the overtime status poll message of not receiving main frame of slave in the step 3 then is judged to be hostdown.

Beneficial effect: do not need special designated host (main frame) before the inventive method networking; All networking nodes can be competed hosted, and algorithm has also guaranteed the flexibility of networking simultaneously, no matter are to increase new node; Node failure is still arranged, can not influence the normal operation of network.Through the present invention; Under half-duplex asynchronous communication bus environment, can easily realize controlling the communication between hinge and the decentralized control unit, networking flexibility is convenient; Do not need special designated host (main frame); Newly add node or malfunctioning node if having, also do not need the people for reconfiguring, major network is operate as normal automatically still.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the present invention is done specifying further, above-mentioned and/or otherwise advantage of the present invention will become apparent.

Fig. 1 is the overall flow figure of the inventive method.

Fig. 2 is the flow chart of the roll-call process of the inventive method.

Fig. 3 is the flow chart of the status poll of the inventive method.

Embodiment

As shown in Figure 1, the invention discloses a kind of half-duplex asynchronous communication self-healing network-building method, may further comprise the steps: step 1, node are sent roll-call message competition hosted, roll-call order 1 ~ N, N is the communication network maximum node number; Can set random delay before sending, the message of avoiding calling the roll sends conflict.Step 2 call the roll to receive: receive that the node littler than own ID sends the roll-call message and transfer slave to, set up all slave lists, if one takes turns to call the roll and only receives that slave responds then transfers main frame to.Step 3, main frame is to all slave circulation transmit status query messages or use message.Step 4, main frame is not received the slave response continuous n time, then from communication network, rejects this node; N is a set point, generally is set at 1 ~ 6.Step 5, main frame are sent inquiry new node message.Step 6, bigger then transfer slave to if main frame is found own ID than new node, otherwise add new node to slave list.

Embodiment

Like Fig. 1 and Fig. 2 and shown in Figure 3, the present embodiment implementation step is following:

1. the normal networking stage

1) after equipment (being node) started, random delay (ID*300+rand (10) * 20) ms began to send the roll-call message, roll-call scope 1～N, and the overtime 300ms that calls the roll receives and responds then Record ID to slave list, and is overtime or receive and respond the ID+1 of roll-call afterwards; Send in the time-delay before the roll-call message, if do not find other message, then think own main frame, if find to have any message, then the roll-call message is sent in cancellation, and getting into is called the roll waits for.

2) slave is replied roll-call after receiving rand (10) the * 20ms that delays time behind the roll-call message.

3) in the roll-call process, be illegal message then repeat some this ID if main frame is found response message, up to response or overtime is arranged.

4) in the roll-call process, if main frame finds that response message ID than own little, then reduces to slave, getting into is called the roll waits for; If slave is found own ID less than host id, be upgraded to main frame after then having sent response message, restart slave is called the roll one by one.

5) main frame roll-call one is taken turns, if roll-call ID>N, networking finishes, and the beginning poll is if < N then returns step 1 to roll-call ID.

6) main frame is to online slave poll successively, the online slave of a poll, and query timeout 300ms does not receive that slave responds this equipment of then from network list, rejecting, and is overtime or receive and respond back slave index i+1; Time-delay rand (10) * 20ms before the each poll of main frame.

7) slave is replied inquiry after receiving rand (10) the * 20ms that delays time behind the polling message.

8) behind the intact 1 time slave of host computer polls (slave index i>communication network in slave number); Main frame is initiated once new oil (gas) filling device inquiry (message comprises all known online slave ID tabulations); If new equipment is found not in tabulation, to reply inquiry behind rand (10) the * 20ms that then delays time.

9) in the new equipment inquiry,, get into and waited for by poll if main frame finds that new equipment ID than own little, then reduces to slave; If new equipment is found own ID less than host id, be upgraded to main frame after then having sent response message, beginning poll slave.

The equipment change stage

Newly-increased node: receive any message during starting time-delay (ID*300+rand (10) * 20) ms, just entering is called the roll and is waited for or new equipment inquiry wait.

Node failure: if the slave fault, continuous 3 polls do not have response with regard to disallowable network; If hostdown, the minimum adapter network hosted of ID in the slave, wait timeout 3s.

The invention provides the self-healing network-building method under a kind of half-duplex asynchronous communication condition; The method and the approach of concrete this technical scheme of realization are a lot, and the above only is a preferred implementation of the present invention, should be understood that; For those skilled in the art; Under the prerequisite that does not break away from the principle of the invention, can also make some improvement and retouching, these improvement and retouching also should be regarded as protection scope of the present invention.The all available prior art of each part not clear and definite in the present embodiment realizes.

Claims

1. a half-duplex asynchronous communication self-healing network-building method is characterized in that, may further comprise the steps:

Step 1, node are sent roll-call message competition hosted, roll-call order 1 ~ N, and N is the communication network maximum node number;

Step 2 call the roll to receive: receive that the node littler than own ID sends the roll-call message and transfer slave to, set up all slave lists, if one takes turns to call the roll and only receives that slave responds then transfers main frame to;

Step 3, main frame is to all slave circulation transmit status query messages or use message;

Step 4, main frame is not received the slave response continuous n time, then from communication network, rejects this node;

Step 5, main frame are sent inquiry new node message;

2. a kind of half-duplex asynchronous communication self-healing network-building method according to claim 1 is characterized in that, comprises the node ID information and the roll-call id information of node self in the roll-call message in the step 1.

3. a kind of half-duplex asynchronous communication self-healing network-building method according to claim 1 is characterized in that, comprises the node ID information and the poll node ID information of node self in the status poll message in the step 3.

4. a kind of half-duplex asynchronous communication self-healing network-building method according to claim 1 is characterized in that the inquiry new node message in the step 5 comprises all present node id informations.

5. a kind of half-duplex asynchronous communication self-healing network-building method according to claim 1 is characterized in that, if the overtime status poll message of not receiving main frame of slave in the step 3 then is judged to be hostdown, returns step 1 again.