JP2010056919A - Network system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a network system capable of normally starting communication even if a network system comprised of one group is constructed. <P>SOLUTION: An engine node 1X transmits/receives a startup frame via communication lines AX, B while using a slot allocated on the basis of an identifier among slots obtained by dividing a communication cycle into N slots, and the received startup frame is used to synchronize communication cycles to each other. A remote control node 2AX is provided with: a startup frame lack detection unit 24 in which, when the identifier is received via the communication line AX, information is transmitted/received by setting a slot for the remote control node itself related beforehand to the received identifier, and it is detected that synchronization to a common communication cycle is disabled by a lack in startup frame; and an auxiliary startup frame-transmitting unit 25 in which, when the lack in startup frame is detected, a startup frame is transmitted via the communication line AX and the inner communication line B. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a network system such as a ship in which a plurality of nodes connected to a network have a predetermined transmission / reception area (slot) for each node in a communication cycle synchronized with each other.

  For the purpose of realizing advanced control, there are systems in which a plurality of nodes control part or all of a control target. In such a system, in order to realize cooperation of the whole system and cooperative operation, a communication device is incorporated in each node and a network in which these devices are connected to each other by using a communication line is used to control each node. Information (hereinafter referred to as information) such as the target state and the execution function of the node is shared.

  In the network, information is transmitted and received based on a communication standard common between nodes. According to one of these communication standards, all nodes synchronize with the common time of the network, and each node transmits / receives information in a transmission / reception area assigned in advance among areas in which communication cycles common to the network are divided into a predetermined number. There is a time division multiplexing method.

  For example, in the communication standard FlexRay (registered trademark, reference www.flexray.com), one communication cycle is composed of a plurality of slots, and a different slot is assigned to each node that transmits information so that information does not collide. Must be. Also, when receiving information, the slot number must be specified.

  In such a communication standard, when a plurality of nodes of the same type are connected to one network, it is necessary to assign different slots to these nodes by some method.

  A ship network system is a system in which a plurality of nodes of the same type are connected to one network. FIG. 11 is a block diagram showing a configuration of a conventional ship network system. In the network system mounted on the ship 110 of FIG. 11, the operation information of the engine nodes 1X and 1Y provided for the two outboard motors 11X and 11Y and the levers 12X and 12Y for forward / reverse travel by the user is input. And remote control nodes 2X and 2Y that transmit to the engine nodes 1X and 1Y are connected.

  As described above, in the ship network system, the engine node and the remote control node are set as one group, and one or more groups are provided. In the example of FIG. 11, the number of groups is two, but may be three or more. With such a network system configuration, even if one group stops due to some failure, it is possible to operate the boat by another group.

  In the example shown in FIG. 11, in order to communicate between nodes in different groups, share information, and enable advanced control, the engine node 1X of group X and the engine node 1Y of group Y Nodes of the same type are connected to a common communication line B. When a time division multiplexing communication standard is used for a network, different information transmission slots must be assigned to the same type of nodes according to the installation position of each group.

  As a method of assigning different information transmission slots, there are a method of assigning slots at the time of product shipment to all nodes and a method of manually assigning slots by a user. In addition, when the groups are connected by a hub and multiple nodes transmit information in the same slot and an information collision occurs, the collision detection means provided in the hub causes the node that is the source of the collision information to be transmitted. On the other hand, a network system has been proposed in which a different identifier is set, a transmission slot is changed, and communication is attempted again (see, for example, Patent Document 1).

  However, in a network system equipped with the above collision detection means, it is assumed that nodes of the same type transmit information in the same slot at the start of communication and collide, so the slot for transmitting information after the collision is changed. However, there is a drawback that it takes time until all nodes start normal communication in different slots.

  In addition, when the number of groups increases and the number of nodes of the same type increases, the number of times of changing the slot for transmitting information also increases, so there is a disadvantage that the time until normal communication starts increases.

  Further, since a hub provided with a collision detection means is used, there is a disadvantage that the cost increases.

  In order to eliminate these disadvantages, the applicant proposes a network system in which the time required for slot allocation to the same type of node is reduced, and each node can transmit information in a different slot in a short time after system startup. (Application on November 2, 2007: Japanese Patent Application No. 2007-285814).

  FIG. 12 is a block diagram showing the configuration of the network system proposed in the previous application. The network system of the previous application will be described with reference to FIG.

  In FIG. 12, the ship 120 is provided with outboard motors 11X and 11Y that are engines on the stern side of the hull, and levers 12X and 12Y that the user operates to move forward and backward on the bow side.

  In FIG. 12, the network system is provided with engine nodes 1X and 1Y for controlling the outboard motors 11X and 11Y, respectively, and remote control nodes 2X and 2Y for inputting operation information of the levers 12X and 12Y, respectively. Yes.

  The engine node 1X and the remote control node 2X are connected by a communication line AX and constitute a group X. The engine node 1Y and the remote control node 2Y are connected by a communication line AY to form a group Y. Further, all nodes are connected by a communication line B different from the communication lines AX and AY.

  The engine nodes 1X and 1Y are set with identifiers X and Y of groups to which the engine nodes 1X and 1Y belong, and assign transmission / reception slots based on these identifiers X and Y. Further, the engine nodes 1X and 1Y synchronize the common time in all nodes by transmitting synchronization acquisition information via the communication lines AX, AY and B, and the remote control node via the communication lines AX and AY. Identifiers X and Y are transmitted to 2X and 2Y. In this way, the remote control nodes 2X and 2Y can perform communication without causing information collision by assigning transmission / reception slots based on the received identifiers X and Y, and all nodes start communication. Can be shortened.

JP 2006-14015 A

  However, in a ship, a network system may be constructed by one group instead of a plurality of groups as shown in the previous application. Therefore, even when a network system composed of one group is constructed using nodes operating according to the method of the previous application, it is necessary to start normal communication. However, for example, when a network system consisting of one group is constructed using a time division multiplexing communication standard that requires a plurality of nodes that transmit synchronization acquisition information when communication is established, such as FlexRay (registered trademark). However, since there is only one node in the group that has an identifier and transmits information for synchronization acquisition, there is a problem that information for synchronization acquisition is insufficient and communication cannot be started normally.

  The present invention has been made to solve the above-described problems, and its purpose is not only when a network system consisting of a plurality of groups is constructed, but also when a network system consisting of a single group is constructed. A network system capable of starting communication normally is obtained.

  In the network system according to the present invention, a node has a communication function via a communication line and a control function for controlling a target device, and a plurality of nodes that realize predetermined control are grouped into one group. Nodes are connected via intra-group communication lines, and the group includes one or more nodes having identifiers for identifying the groups, and one or more groups having different identifiers exist, The first node having an identifier uses the transmission / reception area allocated based on the identifier among the transmission / reception areas obtained by dividing the common communication cycle into a predetermined number. The synchronization acquisition information is transmitted / received via the intra-system communication line and the intra-group communication line, and the received synchronization acquisition information is used. The second node that synchronizes the communication cycle and does not have an identifier receives the synchronization acquisition information transmitted from the first node via the intra-group communication line or the intra-system communication line. In synchronization with the communication cycle common to the first node, the first node transmits the identifier to the second node via the intra-group communication line, and When the second node receives the identifier via the intra-group communication line, the second node sets a transmission / reception area for itself associated with the received identifier in advance, and transmits and receives information. At least one of the nodes of the synchronization acquisition information shortage that detects that the synchronization cannot be synchronized with a common communication cycle due to lack of the synchronization acquisition information Pre-synchronization acquisition for transmitting the synchronization acquisition information via the intra-group communication line and the intra-system communication line when the output means and the synchronization acquisition information shortage detection means detect a lack of the synchronization acquisition information Use information transmission means.

  In the network system according to the present invention, when there are a plurality of groups, the nodes of the same type belonging to each group do not transmit information in the same slot, so the time until all nodes start communication While it is possible to start communication normally while shortening the time, on the other hand, even if there is only one group and synchronization is not possible due to lack of information for synchronization acquisition transmitted by the node with the identifier, The shortage of information can be solved, and communication can be started normally.

Embodiment 1 FIG.
A network system according to Embodiment 1 of the present invention will be described with reference to FIGS. 1 is a diagram showing a configuration of a network system mounted on a ship according to Embodiment 1 of the present invention. In addition, in each figure, the same code | symbol shows the same or equivalent part.

  In FIG. 1, the ship 10 is provided with an outboard motor 11X that is an engine on the stern side of the hull, and a lever 12X that is operated by the user for forward and backward movement on the bow side.

  As shown in FIG. 1, the network system mounted on a ship according to Embodiment 1 of the present invention is composed of one group. This is a network configuration equivalent to that obtained by removing the group Y from the network system including two groups shown in FIG.

  1, the network system according to Embodiment 1 of the present invention is provided with an engine node 1X that controls the outboard motor 11X and a remote control node 2AX that inputs operation information of the lever 12X.

  The engine node 1X and the remote control node 2AX constitute a group X by being connected by a communication line AX (intra-group communication line). Further, a system composed of one group is constructed by connecting with a communication line B (intra-system communication line). The communication line B, which is an intra-system communication line, has an interface 3 with the intra-system communication lines of other groups so that all nodes can be connected when the network system is configured by a plurality of groups.

  Further, the engine node 1X and the remote control node 2AX perform communication conforming to the FlexRay (registered trademark) communication standard via the communication line AX and the communication line B. A group identifier X is set in advance in the engine node 1X.

  FIG. 2 is a block diagram showing a configuration of a remote control node of the network system mounted on the ship according to Embodiment 1 of the present invention.

  In FIG. 2, the remote control node 2AX according to the first embodiment includes a transmission unit 21, a reception unit 22, a synchronous communication unit 23, and a start-up (Startup) frame shortage detection unit (synchronization acquisition information shortage detection means) 24. And a preliminary startup frame transmission unit (preliminary synchronization acquisition information transmission means) 25 and a transceiver 26 are provided.

  Here, the operation of each part of the remote control node 2AX will be described.

  The transmission unit 21 generates a transmission frame excluding a start-up (Startup) frame and makes a transmission request for the transmission frame. The receiving unit 22 performs frame reception processing and captures the received frame. The synchronous communication unit 23 analyzes the received frame, synchronizes with other nodes on the network, communicates, and sets the transmission frame generated by the transmission unit 21 during normal synchronization. The frame is received according to the set transmission slot, and the frame is received according to the set reception slot.

  The start-up frame shortage detection unit 24 is a characteristic part of the network system, and must receive a start-up frame necessary for ensuring synchronization with other nodes on the network even after a specified time has elapsed. For example, it is determined that the startup frame is insufficient. Note that the method for detecting the lack of synchronization acquisition information (startup frame) is not limited to this, and a method of detecting a shortage by monitoring a signal on the network may be used.

  The preliminary startup frame transmission unit 25 is a characteristic part of the network system, and generates a startup frame and requests transmission.

  The transceiver 26 exists as an interface between the node and the communication line so that the synchronous communication unit 23 transmits and receives a frame through the communication line AX and the communication line B, and converts an electrical signal.

  FIG. 3 is a diagram showing a communication cycle configuration of the network system according to the first embodiment of the present invention.

  When performing communication conforming to the FlexRay communication standard, all nodes have a common time and have a communication cycle having a predetermined configuration as shown in FIG. The communication cycle includes N slots and network idle time (NIT). The “slot” is a time domain in which a node transmits and receives information, and only one node can transmit information in one slot. When two or more nodes transmit information in one slot, an information collision occurs and the node cannot receive the information. The “network idle time” is a time for adjusting each node to be synchronized. During communication, communication is performed by repeating this communication cycle.

  In such a communication cycle, the engine node 1X is assigned slot 1 for engine information transmission according to its own identifier X. The reason for assigning slots according to the identifier X is to assign transmission slots that do not collide with each other when a system is configured by two or more groups and there are a plurality of engine nodes having other identifiers. On the other hand, the remote control node 2AX is not assigned an information transmission / reception slot when the node is activated, but retains a preset slot allocation table indicating the correspondence between the identifier and the information transmission / reception slot.

  FIG. 4 shows a structure of a slot allocation table held by the remote control node of the network system according to Embodiment 1 of the present invention.

  In the network system according to the first embodiment, the group is only X, but the remote control node 2AX is also assigned to the slot for transmission / reception corresponding to the identifier Y so as to be able to cope with the configuration in which the group Y exists. Hold on the table.

  When receiving the identifier X, the remote control node 2AX sets the information transmission slot to “5” and the information reception slots to “1” and “2” according to the slot allocation table shown in FIG. Further, according to the slot allocation table, it can be understood that the information received in the slot 1 is information from the engine node 1X of the group X to which the slot belongs, and the information received in the slot 2 is information from the engine node of the group Y.

  If the remote control node 2AX cannot receive the identifier, the slot indicated as “no reception” in FIG. 4 is set as the transmission / reception slot.

  Next, a method for starting synchronization with the common time of nodes in the FlexRay communication standard will be described.

  In the communication standard, a method having a common time is defined in order for all nodes to match the communication cycle and the start time of the slot. In this method, there are two or more cold start nodes (coldstart) nodes that transmit synchronization acquisition information (startup frame) in one network system, and each cold start node transmits a startup frame in one slot. There is a need to. This startup frame must be sent every communication cycle.

  When two or more cold start nodes start transmitting a startup frame, the cold start nodes that have received the startup frame adjust the time, and all the cold start nodes have a common time. Other nodes that are not cold start nodes (non-cold start nodes) receive a start-up frame transmitted from a cold start node having a common time, and synchronize with the common time of the cold start node to perform normal frame transmission. Start. In this way, the communication cycle and the start time of the slot can be matched in all nodes.

  The start-up frame is information for acquiring synchronization, and at the same time, can contain information such as control information in the same way as a normal frame. In the first embodiment, an engine node 1X having an identifier in advance is a cold start node, and a startup frame holding information called identifier X is transmitted in slot 1.

  Here, the specified time provided in the startup frame shortage detection unit 24 of the remote control node 2AX will be described.

  This specified time is a period from when the remote control node 2AX starts measuring time after the start-up when the network system exists in a sufficient number for the cold start node to establish the synchronization until the synchronization can be established. Set the time. That is, if this specified time has elapsed, the network system has failed to establish synchronization, and it can be determined that the startup frame is insufficient. However, since the synchronization establishment time fluctuates due to variations in the startup time and initialization time of each node, the specified time is set with a margin so that a shortage of startup frames is not detected by mistake. .

  Next, the operation of the network system according to the first embodiment will be described with reference to the drawings.

  FIG. 5 is a flowchart showing the operation of the network system according to Embodiment 1 of the present invention.

  First, in step 101, initialization is performed after startup. Here, the engine node 1X is a cold start node, and the remote control node 2AX is a non-cold start node.

  Next, in step 102, the start-up frame shortage detecting unit 24 of the remote control node 2AX starts measuring time.

  Next, in step 103, the engine node 1X sets a transmission / reception slot in accordance with its own identifier X, and starts startup to synchronize between the nodes. At this time, the engine node 1X transmits a startup frame in the slot 1 via the communication line AX and the communication line B.

  Next, in step 104, the remote control node 2AX determines whether or not the startup frame transmitted on the communication line AX and the communication line B is insufficient. When the start-up frame shortage detection unit 24 confirms that the specified time has elapsed, if the start-up frame shortage detection unit 24 has not received a sufficient number of start-up frames to ensure synchronization, it is determined that the start-up frame is short.

  Here, if there are two network system groups and two engine nodes, a shortage of startup frames is not detected, and the process proceeds to step 105. However, in the network system according to the first embodiment, since the cold start node that transmits the startup frame is only the engine node 1X, the startup frame shortage detection unit 24 of the remote control node 2AX determines that the startup frame is insufficient. Then, the process proceeds to Step 110.

  First, a case where communication is established without any problem as in the prior art will be described.

  In step 105, a start-up frame is communicated between engine nodes to acquire a common time with each other and start a synchronized communication cycle.

  Next, in step 106, the engine node transmits a startup frame including the identifier via the intra-group communication line, and transmits a startup frame not including the identifier via the intra-system communication line.

  Next, in step 107, the remote control node receives the startup frame transmitted by the engine node and synchronizes to a common communication cycle.

  Next, in Step 108, the remote control node obtains the identifier of the group to which each corresponds from the startup frame received via the intra-group communication line.

  Next, in step 109, the remote control node sets a transmission / reception slot according to the slot assignment table shown in FIG. 4 based on the received identifier.

  In step 112, all the nodes establish synchronization and enter a normal communication state in which information is transmitted and received.

  Next, the operation when the startup frame for establishing synchronization is insufficient will be described. Since steps 101 to 103 are the same process, the description thereof is omitted.

  In step 104, a shortage of startup frames is detected, and the process proceeds to step 110.

  In step 110, the standby startup frame transmission unit 25 of the remote control node 2AX receives the startup frame shortage determination from the startup frame shortage detection unit 24, generates a startup frame, and issues a startup frame transmission request to the synchronous communication unit 23. put out. At this time, since the remote control node 2AX has not received the identifier, the start-up frame is transmitted using the slot 5 which is the transmission slot indicated as “no reception” in the slot allocation table shown in FIG.

  Next, in step 111, since a startup frame is transmitted from the engine node 1X and the remote control node 2AX, a common time is acquired from each other, and a synchronized communication cycle is started. Then, the process proceeds to step 112, where all nodes establish synchronization and enter a normal communication state in which information is transmitted and received.

  In the flowchart shown in FIG. 5, the startup frame including the identifier is transmitted after the synchronization is established. However, the present invention is not limited to this, and the identifier may be transmitted when transmitting the startup frame. . For example, in step 106, the engine node transmits a startup frame including an identifier. However, the engine node may transmit a startup frame including an identifier at the time of step 103.

  According to the first embodiment, when there are a plurality of groups, a short time can be set by setting transmission slots so that nodes of the same type belonging to each group do not transmit information in the same slot. If all nodes start communication and there is only one group, the lack of synchronization acquisition information is resolved even if synchronization acquisition information sent by the node with the identifier is insufficient Then, communication can be started normally.

  Also, according to the first embodiment, a node that does not have an identifier transmits synchronization acquisition information using a slot that is used in normal communication, thereby leaving many slots available for transmission of other information. be able to.

  In the first embodiment, each node is set to allocate one slot for information transmission, but if it does not overlap with other nodes, a setting is made so that a plurality of slots are used for information transmission. May be.

  In the first embodiment, the engine node has an identifier. However, the present invention is not limited to this, and if one or more nodes in the group hold the identifier, the synchronization acquisition information is insufficient. Communication can be started normally.

Embodiment 2. FIG.
A network system according to Embodiment 2 of the present invention will be described with reference to FIGS. FIG. 6 is a diagram showing a configuration of a network system mounted on a ship according to Embodiment 2 of the present invention.

  6 that have the same reference numerals as those in FIG. 12 and FIG. The remote control node 2AX and the remote control node 2AY have the same configuration, but belong to the group X and the group Y, respectively.

  The network system shown in FIG. 6 shows a state where a failure has occurred in the communication line B of the network system shown in FIG.

  FIG. 7 shows a structure of a slot allocation table held by the remote control node of the network system according to the second embodiment of the present invention.

  The remote control nodes 2AX and 2AY hold the slot allocation table shown in FIG. 7, and set information transmission / reception slots corresponding to the received identifiers. When receiving the identifier X, the remote control nodes 2AX and 2AY have information transmission slots “5”, diagnostic information transmission slots “7” and information according to the slot allocation table shown in FIG. The reception slot is set to “1” and “2”. Further, according to the slot allocation table, it can be understood that the information received in the slot 1 is information from the engine node 1X of the group X to which the slot belongs, and the information received in the slot 2 is information from the engine node 1Y of the group Y. .

  If the remote control nodes 2AX and 2AY cannot receive the identifier, the remote control nodes 2AX and 2AY set the slot indicated by “no reception” in FIG. 7 as the transmission / reception slot, and transmit the startup frame using the slot for transmitting the diagnosis information.

  Next, the operation of the network system according to the second embodiment will be described with reference to the drawings.

  FIG. 8 is a flowchart showing the operation of the network system according to the second embodiment of the present invention.

  First, in step 201, initialization is performed after startup. Here, the engine nodes 1X and 1Y are preset as cold start nodes, and the remote control nodes 2AX and 2AY are preset as non-cold start nodes.

  Next, in step 202, the start-up frame shortage detecting unit 24 of the remote control nodes 2AX and 2AY starts measuring time.

  Next, in step 203, the engine nodes 1X and 1Y set transmission / reception slots according to their own identifiers X and Y, and start up for synchronization between the nodes. At this time, the engine node 1X transmits a startup frame in the slot 1 via the communication line AX and the communication line B. The engine node 1Y transmits a startup frame in the slot 2 via the communication line AY and the communication line B. Here, although frame transmission to the communication line B is performed, since communication via the communication line B is impossible in the second embodiment, no node can receive the frame.

  Next, in step 204, the remote control nodes 2AX and 2AY determine whether or not the start-up frame received from the communication line to which each of them is connected is insufficient. When the start-up frame shortage detection unit 24 confirms that the specified time has elapsed, if the start-up frame shortage detection unit 24 has not received a sufficient number of start-up frames to ensure synchronization, it is determined that the start-up frame is short.

  Here, if the communication line B is communicable, the startup frames from the engine nodes 1X and 1Y are transmitted via the communication line B. Therefore, the lack of the startup frame is not detected, and the process proceeds to step 205. However, in the network system according to the second embodiment, the remote control nodes 2AX and 2AY can receive only one startup frame via the communication lines AX and AY, respectively, and the startup frame shortage detection unit 24 of the remote control nodes 2AX and 2AY. Determines that the startup frame is insufficient, and proceeds to step 210.

  When communication is established without any problem as in the conventional case, steps 205 to 209 and 217 are the same as steps 105 to 109 and 112 of FIG. .

  The operation when the startup frame for establishing synchronization is insufficient will be described.

  In step 210, the standby startup frame transmission unit 25 of the remote control nodes 2AX and 2AY receives the determination of the startup frame shortage from the startup frame shortage detection unit 24, generates a startup frame, and transmits the startup frame to the synchronous communication unit 23. Make a request. At this time, since neither of the remote control nodes 2AX and 2AY has received the identifier, the start-up frame is used by using the slot 7 which is the diag information transmission slot indicated as “no reception” in the slot allocation table shown in FIG. Send.

  Next, in step 211, the engine node 1X and the remote control node 2AX transmit a startup frame via the communication line AX, so that they can acquire a common time and start a synchronized communication cycle. The engine node 1Y and the remote control node 2AY transmit a start-up frame via the communication line AY and start a synchronized communication cycle. At this time, the configuration of the communication cycle of the communication lines AX and AY is shown in FIG.

  As shown in FIG. 9, two start-up frames are transmitted on each of the communication lines AX and AY, and synchronization can be established. However, at this time, since the remote control nodes 2AX and 2AY have not received the identifier, the startup frame is transmitted using the slot set when neither of the identifiers is received.

  Next, in step 212, the engine nodes 1X and 1Y transmit startup frames including the identifiers X and Y via the communication lines AX and AY, respectively, and transmit startup frames that do not include the identifier via the communication line B.

  Next, in step 213, the remote control nodes 2AX and 2AY transmit diagnostic information including that the communication via the communication line B is impossible in a startup frame. In this way, by using a slot that is not used in normal communication and transmitting a frame including the contents of the failure, the engine nodes 1X and 1Y obtain information on the failure occurring in the remote control nodes 2AX and 2AY. be able to.

  Next, in step 214, the remote control nodes 2AX and 2AY receive the start-up frames including the identifiers X and Y from the engine nodes 1X and 1Y via the communication lines AX and AY, respectively. obtain.

  Next, in step 215, the remote control nodes 2AX and 2AY set a transmission / reception slot according to the slot assignment table shown in FIG. 7 based on the received identifier. At this time, since the remote control nodes 2AX and 2AY are reset to slots based on the identifier, the synchronization established in each node is released.

  Next, in step 216, the remote control nodes 2AX and 2AY transmit a start-up frame using the diagnostic information transmission slot among the slots set based on the identifiers X and Y, respectively, and again communicate with the engine nodes 1X and 1Y. Establish synchronization.

  Next, in step 217, a normal communication state in which information is transmitted and received is entered. The configuration of the communication cycle of the communication lines AX and AY at this time is shown in FIG.

  In the communication cycle of FIG. 10, communication is performed in the slots shown in the slot allocation table of FIG. 7 on each of the communication lines AX and AY. In this way, even if the communication line B cannot be communicated due to a failure, synchronization is established within the group, and communication between the remote control node and the engine node, which is the minimum necessary for operating the outboard motor, is ensured. ing.

  In the flowchart shown in FIG. 8, the start-up frame including some information is transmitted after synchronization is established. However, the present invention is not limited to this. Good. For example, the remote control node transmits a startup frame including diagnosis information at step 213, but may transmit a startup frame including diagnosis information at the time of step 210.

  According to the second embodiment, when a node that does not have an identifier transmits synchronization acquisition information, by using a slot that is not used in normal communication, the network state such as a lack of cold start nodes is changed to other nodes. It becomes possible to inform to.

  Further, according to the second embodiment, even when a failure occurs and a certain group becomes unable to communicate with another group, synchronization is established within the isolated group and is determined for normal communication. Communication can be performed using the slot. Furthermore, when other nodes join the network after recovering from a failure, information is transmitted using the transmission area defined by the identifier, so communication can be performed without colliding with the transmission area of other nodes. Is possible.

  In the second embodiment, the engine node has an identifier. However, the present invention is not limited to this, and the group is such that the engine node has an identifier in one group and the remote control node has an identifier in the other group. It is sufficient that one or more nodes hold the identifier.

  In the network systems shown in the first and second embodiments, communication is performed in accordance with the FlexRay (registered trademark) communication standard. However, the present invention is not limited to this, and a node that transmits synchronization acquisition information to establish synchronization. May be any time-division multiplexing communication standard that requires a plurality.

It is a figure which shows the structure of the network system mounted in the ship which concerns on Embodiment 1 of this invention. It is a block diagram which shows the structure of the remote control node of the network system which concerns on Embodiment 1 of this invention. It is a figure which shows the structure of the communication cycle of the network system which concerns on Embodiment 1 of this invention. It is a figure which shows the structure of the slot allocation table which the remote control node of the network system which concerns on Embodiment 1 of this invention hold | maintains. It is a flowchart which shows operation | movement of the network system which concerns on Embodiment 1 of this invention. It is a figure which shows the structure of the network system mounted in the ship which concerns on Embodiment 2 of this invention. It is a figure which shows the structure of the slot allocation table which the remote control node of the network system which concerns on Embodiment 2 of this invention hold | maintains. It is a flowchart which shows operation | movement of the network system which concerns on Embodiment 2 of this invention. It is a figure which shows the structure of the communication cycle of communication line AX, AY immediately after the network system which concerns on Embodiment 2 of this invention acquires common time. It is a figure which shows the structure of the communication cycle of communication line AX, AY of the normal communication state of the network system which concerns on Embodiment 2 of this invention. It is a figure which shows the structure of the network system of the conventional ship. It is a figure which shows the structure of the network system of the ship of a previous application.

Explanation of symbols

  1X engine node, 1Y engine node, 2AX remote control node, 2AY remote control node, 3 interface, 11X outboard motor, 12X lever, 21 transmission unit, 22 reception unit, 23 synchronous communication unit, 24 startup frame shortage detection unit, 25 preliminary startup Frame transmission unit, 26 transceiver, AX communication line, AY communication line, B communication line.

Claims (4)

A node has a communication function via a communication line and a control function for controlling a target device. A plurality of nodes that realize predetermined control are grouped together into one group, and each node in the group is connected via an intra-group communication line. The group includes at least one node having an identifier for identifying the group, and at least one group having a different identifier exists, and all the nodes in the network system have an intra-system communication line. Connected through
The first node having an identifier uses the transmission / reception area allocated based on the identifier among the transmission / reception areas obtained by dividing a common communication cycle into a predetermined number, and the intra-system communication line and the intra-group communication line The synchronization acquisition information is transmitted and received, and the communication cycle is synchronized with each other using the received synchronization acquisition information,
A second node having no identifier receives the synchronization acquisition information transmitted from the first node via the intra-group communication line or the intra-system communication line, and Synchronized to a common communication cycle,
The first node transmits the identifier to the second node via the intra-group communication line, and the second node transmits the identifier via the intra-group communication line. In a network system for transmitting and receiving information by setting a transmission / reception area for itself associated in advance with the received identifier,
At least one of the second nodes is
Synchronization acquisition information shortage detection means for detecting that synchronization with a common communication cycle cannot be performed due to lack of the synchronization acquisition information;
Preliminary synchronization acquisition information transmission means for transmitting the synchronization acquisition information via the intra-group communication line and the intra-system communication line when the synchronization acquisition information shortage detection means detects a lack of the synchronization acquisition information. A network system characterized by comprising: The second node comprising the synchronization acquisition information shortage detection means and the preliminary synchronization acquisition information transmission means performs normal communication in its own transmission area associated with each of the identifiers of all groups. The network system according to claim 1, wherein the synchronization acquisition information is transmitted from the preliminary synchronization acquisition information transmitting unit using a transmission area to be performed. The second node comprising the synchronization acquisition information shortage detection means and the preliminary synchronization acquisition information transmission means performs normal communication in its own transmission area associated with each of the identifiers of all groups. The network system according to claim 1, wherein the synchronization acquisition information is transmitted from the preliminary synchronization acquisition information transmission unit using a transmission area that is not used. The second node having the synchronization acquisition information shortage detection unit and the standby synchronization acquisition information transmission unit transmits the synchronization acquisition information from the backup synchronization acquisition information transmission unit and synchronizes with the communication cycle. When an identifier is received via the intra-group communication line, information is transmitted / received by setting a transmission / reception area for the identifier associated with the received identifier in advance. A network system according to any of the above.

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