JP2023019933A - Lower level node recognition method - Google Patents

Abstract

To provide a lower level node recognition method which can reduce the recognition time of a lower level node.SOLUTION: An upper level ECU transmits mounted product response requests to a plurality of lower level ECUs connected to a communication line to request transmission of mounted product responses (S11). On receiving the mounted product response request, each of the plurality of lower level ECUs transmits a mounted product response in synchronization with the other lower level ECUs. The upper level ECU receives each mounted product response, and based on the plurality of received mounted product responses and bit assignment, recognizes the products of the lower level ECUs connected to the communication line (S12, S13). At this time, the upper level ECU receives a connection signal if a connection signal and a non-connection signal are assigned to the same bit of different mounted product responses. From the product information associated with the received connection signal bit in the bit assignment, the upper level ECU recognizes the products of the lower level nodes connected to the communication line.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a lower node recognition method for recognizing lower nodes connected to communication lines.

As described in Patent Document 1, there is a communication system in which a communication line includes a plurality of lower nodes and an upper node communicating with each lower node.

A higher node transmits a setting request signal representing one of a plurality of pieces of identification information to be set in each lower node onto a communication line. Thereafter, when the upper node receives a setting response signal transmitted over the communication line from one of the plurality of lower nodes, the upper node receives a setting request signal representing identification information that has not yet been transmitted as a setting request signal among the plurality of pieces of identification information. is sent over the wire. As a result, the upper node sequentially transmits a plurality of setting request signals representing a plurality of pieces of identification information onto the communication line.

Until the identification information of the lower node is set, each lower node receives a setting request signal transmitted from the upper node via the communication line, and thereafter until a predetermined monitoring time elapses. It monitors whether or not a setting response signal has been transmitted on the communication line from another lower node. Each lower node, when it is determined that the setting response signal has not been transmitted from another lower node until the monitoring time elapses, transmits the setting response signal over the communication line, and receives the setting response signal via the communication line this time. The identification information indicated by the setting request signal is set as its own identification information.

Japanese Patent No. 4211683

The configuration of the prior art document allows the upper node to recognize each lower node. However, in the configuration of the prior art document, it is necessary to set a monitoring time and establish communication with each of the plurality of lower nodes. Therefore, the configuration of the prior art document has a problem that it takes a long time to recognize a plurality of lower nodes.

One object of the disclosure is to provide a subordinate node recognition method capable of shortening the subnode recognition time.

The subordinate node recognition method disclosed herein comprises:
Recognizing a lower node in a network comprising a communication line, an upper node connected to the communication line, and a plurality of lower nodes as electronic control devices connected to the communication line and transmitting and receiving communication frames to and from the upper node. a method,
The upper node has product group information in which product information indicating the product of each lower node is associated with each of a plurality of divided areas in the communication frame, and
In each lower node, as a communication frame, a connection signal indicating that it is connected to a communication line is assigned to an area associated with product information indicating its own product, and a non-connection signal is assigned to other areas. It transmits a product information signal,
a request step (S11, S11a) in which an upper node transmits a request signal to a plurality of lower nodes connected to a communication line to request transmission of a product information signal;
a transmitting step (S23) in which each of the plurality of lower nodes transmits a product information signal in synchronization with other lower nodes when it receives the request signal;
Recognition in which the upper node receives a plurality of product information signals transmitted in the transmission step, and recognizes the products of the lower node connected to the communication line based on the received plurality of product information signals and product group information. Steps (S12, S13), and
In the recognition process, when the connection signal and the non-connection signal are assigned to the same area in the different product information signals transmitted in the transmission process, the connection signal is received, and the connection signal is received in the area of the received connection signal in the product group information. It is characterized by recognizing the product of the lower node connected to the communication line from the associated product information.

Thus, according to the lower node recognition method, when a connection signal and a non-connection signal are assigned to the same area in different product information signals transmitted synchronously, the upper node receives the connection signal. By receiving a plurality of synchronously transmitted product information signals, the upper node recognizes the area where the connection signal was received. Therefore, the upper node can recognize the product of the lower node connected to the communication line from the product information associated with the area of the received connection signal in the product group information. Therefore, the low-order node recognition method can reduce the recognition time of low-order nodes as compared with a configuration in which a plurality of low-order nodes transmit product information signals at different timings.

The multiple aspects disclosed in this specification employ different technical means to achieve their respective objectives. Reference numerals in parentheses described in the claims and this section are intended to exemplify the correspondence with portions of the embodiments described later, and are not intended to limit the technical scope. Objects, features, and advantages disclosed in this specification will become clearer with reference to the following detailed description and accompanying drawings.

1 is a block diagram showing a schematic configuration of an in-vehicle network in a first embodiment; FIG. 4 is a flowchart showing recognition processing of a host ECU in the first embodiment; 4 is a flowchart showing recognition processing of a lower ECU in the first embodiment; It is a drawing showing the relationship between the upper ECU and the lower ECU in the first embodiment. 4 is a time chart showing processing operations of a higher-level ECU and a lower-level ECU in the first embodiment; It is drawing which shows the voltage waveform of a communication line and low-order ECU in 1st Embodiment. It is a drawing showing bit assignment in the first embodiment. 4 is a flowchart showing ID setting processing of a host ECU in the first embodiment; 4 is a flowchart showing ID setting processing of a lower ECU in the first embodiment; 9 is a flow chart showing recognition processing of a higher-level ECU in the second embodiment; 9 is a flowchart showing recognition processing of a lower ECU in the second embodiment; 9 is a time chart showing processing operations of a higher-level ECU and a lower-level ECU in the second embodiment; 9 is a time chart showing processing operations of a higher-level ECU and a lower-level ECU in Modification 1; 10 is a flowchart showing ID setting processing of a host ECU in Modification 2. FIG. 11 is a flow chart showing first collision processing of a host ECU in modification 2. FIG. FIG. 11 is a flowchart showing second collision processing of a higher-level ECU in modification 2; FIG. 14 is a flowchart showing third collision processing of a higher-level ECU in Modification 2. FIG.

A plurality of modes for carrying out the present disclosure will be described below with reference to the drawings. In each form, the same reference numerals may be given to the parts corresponding to the matters described in the preceding form, and redundant description may be omitted. In each form, when only a part of the configuration is described, other parts of the configuration can be applied with reference to the previously described other modes.

In the drawings, the upper ECU is denoted as MECU, the lower ECU as SECU, the arithmetic device as CPD, the communication device as CMD, and the storage device as MMD. Also, SECU1, SECU2, SECU3, etc. are also described in order to distinguish each subordinate ECU.

(First embodiment)
The lower node recognition method of the first embodiment will be described with reference to FIGS. 1 to 9. FIG. In this embodiment, as an example, a low-order node recognition method in an in-vehicle network 100 that can be mounted on a vehicle is adopted. The lower node recognition method is a method of automatically recognizing a lower node (lower ECU 20 ) connected to the communication line 30 of the in-vehicle network 100 . That is, the lower node recognition method is a method of automatically recognizing the lower ECU 20 when adding, deleting, or replacing the lower ECU 20 with respect to the in-vehicle network 100 . In particular, the lower node recognition method is a method of recognizing the lower node product connected to the communication line 30 . ECU is an abbreviation for Electronic Control Unit.

<In-vehicle network>
The in-vehicle network 100 includes devices such as an upper ECU 10, a lower ECU 20, and a communication line 30, as shown in FIG. The in-vehicle network 100 is configured using devices conforming to communication protocols such as LIN and CXPI. LIN is an abbreviation for local interconnect network. CXPI is an abbreviation for clock extension peripheral interface.

In the in-vehicle network 100 , the upper ECU 10 and the lower ECU 20 are connected to the communication line 30 . Further, the in-vehicle network 100 has a plurality of lower ECUs 20 connected to the communication line 30 . The upper ECU 10 and each lower ECU 20 are configured to be able to communicate with each other via a communication line 30 . In the in-vehicle network 100, the upper ECU 10 and the lower ECU 20 communicate using, for example, communication frames. That is, in the in-vehicle network 100, the upper ECU 10 and the plurality of lower ECUs 20 transmit and receive communication frames. It can be said that the upper ECU 10, the lower ECU 20, and the communication line 30 comply with the communication protocol as described above.

The communication line 30 has a predetermined connection upper limit, which is the number of connectable nodes (ECUs). In this embodiment, as an example, an example in which 16 nodes can be connected to the communication line 30 is adopted. Therefore, the communication line 30 can connect one upper ECU 10 and 15 lower ECUs 20 as nodes. Communication line 30 is also referred to as a communication bus.

As shown in FIG. 6 , the communication line 30 can take a voltage waveform when communication frames are transmitted from a plurality of lower-level ECUs 20 . Here, voltage waveforms of three subordinate ECUs (SECU1 to SECU3) and the communication line 30 are used as an example.

The communication line 30 has a voltage waveform overwritten with a strong signal in the signal transmitted from each lower ECU 20 . Here, a strong signal is 0 and a weak signal is 1. Thus, signal 1 is overwritten with signal 0. For example, bit3 in the data area is 0 for SECU1 and 1 for SECU2 and SECU3. Therefore, the communication line 30 becomes 0. 0 can also be said to be a low level. On the other hand, 1 can be said to be a high level.

In addition, in this embodiment, as an example, an example in which one communication line 30 is connected to the host ECU 10 is adopted. However, the present disclosure is not limited to this, and multiple communication lines 30 may be connected to the host ECU 10 .

<Upper ECU>
The host ECU 10 corresponds to a host node. The host ECU 10 includes an arithmetic device 11, a storage device 12, and a communication device 13, as shown in FIG. When the power source of the vehicle is turned on, the host ECU 10 starts to be supplied with power and operates. Vehicle power is turned on when the ignition switch is turned on.

A CPU or the like can be adopted as the arithmetic unit 11 . The arithmetic device 11 performs arithmetic processing by executing a program stored in the storage device 12 . Further, the calculation device 11 performs calculation processing while referring to the contents stored in the storage device 12 . As a result, the higher-level ECU 10 executes processing operations that will be described later.

The storage device 12 includes non-volatile memory and volatile memory. The nonvolatile memory of the storage device 12 stores programs executed by the arithmetic device 11 . The volatile memory of the storage device 12 temporarily stores the calculation result of the calculation device 11 and the like.

An ID storage area 121 is provided in the nonvolatile memory of the storage device 12 . The ID storage area 121 stores a plurality of different selectable IDs. The selectable ID is information for individually recognizing the lower ECU 20 connected to the communication line 30 . A selectable ID is information that can be selected by a plurality of lower-level ECUs 20 . A selectable ID corresponds to identification information.

The same number of selectable IDs as the number of lower ECUs 20 connectable to the communication line 30 are stored in the ID storage area 121 . In this embodiment, as an example, an example in which 15 selectable IDs 1 to 15 are stored as selectable IDs is adopted. However, the present disclosure is not limited to this, and the ID storage area 121 may not be provided.

A bit assignment (PMI) 122 is stored in the non-volatile memory of the storage device 12 . The bit assignment 122 corresponds to product group information. In the bit assignment 122, as shown in FIG. 7, product information PI indicating the product of each lower ECU 20 is associated with each of a plurality of divided areas in the communication frame. In this embodiment, 1 bit is adopted as the divided area. However, this area can be adopted even if it is several bits.

More specifically, the data area of the communication frame consists of eight data, and each data has 8 bits. The bit assignment 122 associates each bit of the communication frame with product information. In FIG. 7, for example, the first product information PI1 is associated with the first bit (bit1) of Data1, the second product information PI2 is associated with the second bit (bit2) of Data2, and the ninth product information PI9 is associated with the first bit of Data2. It can be said that the first product information PI1 is the product information of the product 1 . Similarly, the second product information PI2 can be said to be the product information of the product 2, and the ninth product information PI9 can be said to be the product information of the product 9. Note that, in this embodiment, an 8-byte communication frame is used as an example. However, the data area of the communication frame in the present disclosure is not limited to this.

Therefore, the upper ECU 10 recognizes the product (the lower ECU 20) connected to the communication line 30 by the product information signal included in the communication frame described later and the bit assignment 122. FIG. A product recognized as being connected to the communication line 30 can be called a connected product or an installed product. This point will be described in detail later.

In addition, the non-volatile memory of the storage device 22 is configured to be able to store the mounted product. In this case, the non-volatile memory of the storage device 22 stores the product information of the mounted product as the mounted product. In other words, the product information of the recognized product is stored in the non-volatile memory of the storage device 22 . In the non-volatile memory of the storage device 22, the communication line 30 and the product information of the recognized product are stored in association with each other.

Further, the storage device 12 may store each of the selectable ID1 to ID15 and the product information PI of each lower ECU 20 in association with each other. As will be described in detail later, in this embodiment, as an example, each lower ECU 20 selects one from a plurality of selectable ID1 to ID15. Then, the upper ECU 10 associates each selectable ID1 to ID15 with the product information PI of the lower ECU 20 and stores (registers) them in the storage device 12 . That is, the storage device 12 stores the selectable ID selected by the lower ECU 20 and the product information PI of the lower ECU 20 that selected the selectable ID in association with each other. Therefore, the storage device 12 does not store the product information PI until the identification information setting process is executed. Storing the selectable ID and the product information PI in association with each other is also referred to as registering the selectable ID.

The selectable ID selected by the lower ECU 20 is one of selectable ID1 to ID15. Also, a registered selectable ID (selection ID) can be said to be a registered ID. Furthermore, since the registered ID is a selected ID that has already been selected by the lower ECU 20, it can also be said to be a selected ID.

FIG. 1 illustrates an example in which selectable ID1 is associated with product information PI1, and selectable ID2 is associated with product information PI2. Note that the communication line 30 is not necessarily connected to the upper ECU 10 and the lower ECU 20 that correspond to the upper limit number of connections. Therefore, selectable ID1 to ID15 may all be associated with product information PI, or may be partially associated with product information PI.

In this embodiment, a selectable ID is used as identification information. However, the present disclosure is not limited to this, and an address of each lower ECU 20 in the in-vehicle network 100 can also be adopted.

Further, according to the present disclosure, there may exist a higher-level ECU 10 that uses a selectable ID as identification information to be registered and a higher-level ECU 10 that uses an address. In this case, the lower ECU 20 selects either the selectable ID or the address as identification information to be included in the reply information. As a result, the versatility of the upper ECU 10 and the lower ECU 20 can be enhanced.

The communication device 13 includes a transceiver and the like. The communication device 13 is a device that performs communication via the communication line 30 . The arithmetic device 11 communicates (transmits and receives) with each lower ECU 20 using the communication device 13 . The arithmetic device 11 transmits, for example, a mounted product response request, an ID setting determination request, a selectable ID, a selection command, an ID return request, and the like. Further, the arithmetic unit 11 receives a product recognition request, a mounted product response, an ID setting request, a selection ID, product information PI, and the like.

Note that the processing operation of the host ECU 10 will be described later.

<Lower ECU>
The lower ECU 20 corresponds to a lower node. As shown in FIG. 1, the subordinate ECU 20 includes an arithmetic device 21, a storage device 22, and a communication device 23 as a basic configuration. When the vehicle power is turned on, the lower ECU 20 starts to be supplied with power and operates.

A CPU or the like can be adopted as the arithmetic unit 21 . The arithmetic device 21 performs arithmetic processing by executing a program stored in the storage device 22 . Further, the calculation device 21 performs calculation processing while referring to the contents stored in the storage device 22 . Accordingly, the lower ECU 20 executes processing operations that will be described later.

The storage device 22 includes non-volatile memory and volatile memory. The nonvolatile memory of the storage device 22 stores programs executed by the arithmetic device 11 . The volatile memory of the storage device 22 temporarily stores the calculation result of the calculation device 11 and the like.

The storage device 22 may be configured to be able to store all selectable ID1 to ID15 transmitted from the host ECU 10 . The lower ECU 20 stores all selectable ID1 to ID15 in the storage device 22 in order to select one selectable ID from all selectable ID1 to ID15. Therefore, the storage device 22 should be able to store all selectable ID1 to ID15 at least temporarily. It should be noted that the one selected by the lower ECU 20 among all the selectable ID1 to ID15 can be said to be a selected ID. For example, the selectable ID1 selected from the lower ECU 20 can be called the selected ID1.

The storage device 22 stores product information PI of the lower ECU 20 in which it is provided. The product information PI is information determined for each product that is the lower ECU 20 . The product information PI can also be said to be information determined at the time of manufacture. Therefore, the lower ECU 20 is provided with the same product information PI for the same product. The product information PI is stored in the storage device 22 when the lower ECU 20 is manufactured. For example, FIG. 1 shows the lower ECU 20 storing the product information PI2 in the storage device 22. As shown in FIG. The product information PI can also be said to be a product information number.

However, the present disclosure is not so limited. The product information PI may include an area that is determined when the lower ECU 20 is manufactured and an area that is determined after assembly to the in-vehicle network 100 . In other words, the product information PI may include information that is determined when the lower ECU 20 is manufactured and information that is determined after it is installed in the in-vehicle network 100 .

Also, the lower ECU 20 transmits a product information signal as a communication frame. A communication frame has a header area and a data area. The product information signal is a signal included in the data area of the communication frame. The product information signal is a signal in which a connection signal is assigned to an area associated with the product information PI indicating the product of the lower ECU 20 in the communication frame, and a non-connection signal is assigned to other areas. A connection signal is a signal indicating that the lower ECU 20 is connected to the communication line 30 . A disconnection signal is a signal indicating that the lower ECU 20 is not connected to the communication line 30 . Here, 0 is adopted as the connection signal and 1 is adopted as the non-connection signal.

As an example, the lower ECU 20, which is the product indicated by the product information PI3, will be described. This subordinate ECU 20 is configured to be able to transmit 110111 . . . 1 as a product information signal. In other words, the subordinate ECU 20 has 110111 .

The lower ECU 20 is configured to transmit a communication frame including a product information signal to the data area while being connected to the communication line 30 . Further, the lower ECU 20 transmits a communication frame including a product information signal composed of signals (values) from bit1 of Data1 to bit8 of Data8. Bit8 of Data1 is followed by bit1 of Data2. Also, bit8 of Data2 may follow bit1 of Data1. The same applies to other Data.

In addition, the non-volatile memory of the storage device 22 is configured to be able to store information indicating that the product has been recognized. This information is transmitted from the host ECU 10 . This information is not stored in the storage device 22 of the lower ECU 20 that the higher ECU 10 does not recognize. In other words, this information is not stored in the storage device 22 of the lower ECU 20 newly connected to the communication line 30 . In the following, information indicating that the product has been recognized is also simply referred to as product recognition.

It can be said that the lower ECU 20 being connected to the communication line 30 is installed in the in-vehicle network 100 . Therefore, the connection signal can be said to be a mounting signal, and the non-connection signal can be said to be a non-mounting signal. Further, communication frames containing product information signals are also referred to as on-board product responses.

A plurality of lower-level ECUs 20 having the same basic configuration are connected to the communication line 30 . Further, as the subordinate ECU 20, a product as an independent electronic control device, an electronic control device provided in a product such as an actuator or a sensor, or the like can be adopted. Examples of products that can be adopted include power window motors (PW motors) and door lock sensors. However, the products exemplified here are merely examples, and other products can also be adopted.

Here, for example, a case where a PW motor is adopted as a product will be described. In this case, the communication line 30 is connected to the PW motor for the driver's seat, the PW motor for the passenger's seat, the PW motor for the right rear seat, and the PW motor for the left rear seat. Each PW motor has a motor and a subordinate ECU 20 that drives and controls the motor. The storage device 22 of each sub-ECU 20 stores the same product information PI indicating that it is a PW motor.

Furthermore, the lower ECU 20 does not have information such as an ID that can identify itself at the time of manufacture. That is, the lower ECU 20 does not have information that can identify itself until it receives the selectable ID from the upper ECU 10 . Therefore, if a plurality of lower ECUs 20 are the same product, the upper ECU 10 cannot individually recognize (identify) each lower ECU 20 . In other words, the upper ECU 10 cannot individually control the lower ECUs 20 if the lower ECUs 20 are the same product. Therefore, the lower node recognition method provides a method for the upper ECU 10 to recognize the lower ECU 20 individually. This point will be described in detail later. In addition, it can be said that the lower ECUs 20 of the same product are the same lower ECUs 20 .

The communication device 23 includes a transceiver and the like. The communication device 23 is a device that performs communication via the communication line 30 . The computing device 21 communicates with the host ECU 10 using the communication device 23 . The arithmetic device 21 receives, for example, a mounted product response request, an ID setting determination request, a selectable ID, a selection command, an ID return request, and the like. Further, the arithmetic device 21 transmits a product recognition request, a mounted product response, an ID setting request, a selection ID, product information PI, and the like. It can also be said that the lower ECU 20 transmits data including the selection ID and the product information PI.

<Processing operation: Recognition processing>
Here, the recognition processing of the upper ECU 10 and each lower ECU 20 will be described with reference to FIGS. 2 to 6. FIG. More specifically, the processing operations related to the lower node recognition method in the upper ECU 10 and each lower ECU 20 will be described. The recognition process is a process in which the upper ECU 10 recognizes the lower ECU 20 connected to the communication line 40 . Here, an example in which the SECU 1 is newly added to the communication line 30 is adopted. SECU2 and SECU3 have already been recognized as products.

When the vehicle is powered on, the host ECU 10 starts the process shown in the flowchart of FIG. Similarly, each lower ECU 20 starts the process shown in the flowchart of FIG. 3 when the vehicle power is turned on. Each lower ECU 20 performs the same processing. Therefore, one sub-ECU 20 will be exemplified for explanation.

First, the processing operation of the host ECU 10 will be described with reference to FIG.

In step S10, it is determined whether or not a product recognition request has been received. If the upper ECU 10 determines that it has received the product recognition request from the lower ECU 20, it proceeds to step S11. In the example of FIG. 4, SECU1 will transmit the product recognition request. Therefore, the host ECU 101 proceeds to step S11 to receive the product recognition request.

In addition, when the lower ECU 20 is not newly added to the communication line 40, all the lower ECUs 20 have already been recognized as products. Therefore, all subordinate ECUs 20 do not transmit a product recognition request. Therefore, the host ECU 10 does not receive the product recognition request. That is, the upper ECU 10 considers that recognition of the lower ECU 20 is not necessary, and terminates the flowchart of FIG.

In step S11, a mounted product response request is transmitted (request step). The mounted product response request is a signal requesting transmission of a product information signal, and corresponds to a request signal. The upper ECU 10 transmits a mounted product response request via the communication line 30 to all the lower ECUs 20 connected to the communication line 30 . As a result, the upper ECU 10 requests all the lower ECUs 20 to transmit the product information signal. A plurality of lower ECUs 20 are connected to the communication line 30 . For this reason, it can be said that the upper ECU 10 transmits the mounted product response request to the plurality of lower ECUs 20 connected to the communication line 30 .

In the examples of FIGS. 4 and 5, the host ECU 10 transmits a mounted product response request to the SECUs 1-3. At this time, as shown in the first frame of FIG. 5, the voltage waveform of the communication line 30 indicates the mounted product response request.

Note that the in-vehicle network 100 may have a plurality of communication lines 30 connected to the host ECU 10 . In this case, the upper ECU 10 transmits a mounted product response request to the lower ECU 20 connected to the communication line 30 that has received the product recognition request. Moreover, the upper ECU 10 may transmit the mounted product response request to the lower ECU 20 connected to the communication line 30 regardless of whether the product recognition request is received. Thereby, the upper ECU 10 can confirm the connection of the lower ECU 20 . That is, the upper ECU 10 can confirm that the lower ECU 20 connected to the communication line 30 has not been changed.

In step S12, it is determined whether or not a mounted product response has been received (recognition step). The upper ECU 10 determines whether or not it has received a mounted product response from the lower ECU 20 . If the high-order ECU 10 determines that it has received the mounted product response from the low-order ECU 20, it proceeds to step S13, and if it does not determine that it has received it, it returns to step S11. Thus, the upper ECU 10 receives the mounted product response from all the lower ECUs 20 by transmitting the mounted product response request to all the lower ECUs 20 . That is, the upper ECU 10 receives product information signals from all the lower ECUs 20 . Therefore, the host ECU 10 receives a plurality of product information signals.

As will be described later, in the lower node recognition method, all the lower ECUs 20 synchronize and transmit the mounted product response. In other words, the low-order node recognition method causes all the low-order ECUs 20 to collide with the mounted product responses. Therefore, as shown in FIGS. 5 and 6, all lower-level ECUs 20 transmit the mounted product response at the same timing.

In step S13, the mounted product is recognized and stored (recognition step). The upper ECU 10 recognizes the products of the lower ECU connected to the communication line 30 based on the received product information signals and the product group information. Then, the host ECU 10 associates the communication line 30 with the recognized product and stores them in the non-volatile memory of the storage device 12 .

The upper ECU 10 receives the connection signal when the connection signal (0) and the non-connection signal (1) are assigned to the same bit in the different product information signals transmitted from all the lower ECUs 20 . In the example of FIG. 6, different product information signals are transmitted from each of the SECUs 1-3. In the communication line 30, bit3 and bit6 of Data1 and bit1 of Data2 form a voltage waveform indicating a connection signal. Therefore, the host ECU 10 receives the connection signal at bit3 and bit6 of Data1 and bit1 of Data2. It should be noted that the host ECU 10 receives the non-connection signal at other bits.

Then, the upper ECU 10 recognizes the product of the lower ECU 20 connected to the communication line 30 from the product information PI associated with the bit of the received connection signal in the bit assignment 122 . In bit assignment 122, bit3 of Data1 is associated with product3, bit6 of Data1 is associated with product6, and bit1 of Data2 is associated with product9. Therefore, the upper ECU 10 recognizes that the communication line 30 is connected to the lower ECUs 20 of the products 3 , 6 and 9 . In other words, the lower ECU 20 connected to the communication line 30 recognizes the products 3, 6, and 9 as products. Then, the host ECU 10 associates the communication line 30 with the product 3, the product 6, and the product 9, and stores them in the non-volatile memory of the storage device 12. FIG.

In step S14, it notifies that the product has been recognized. The upper ECU 10 notifies all the lower ECUs 20 via the communication line 30 that the product has been recognized.

It should be noted that the upper ECU 10 may transmit identification information to each lower ECU 20 after recognizing the lower ECU 20 . This is because the upper ECU 10 recognizes all the lower ECUs 20 individually. As the identification information, an ID or an address of each lower ECU 20 in the in-vehicle network 100 can be used. The identification information may be assigned to each lower ECU 20 by the upper ECU 10 or may be selected by each lower ECU 20 . An ID setting process will be described later as an example of a method of setting identification information.

Next, the processing operation of the lower ECU 20 will be described with reference to FIG.

In step S20, it is determined whether or not the product has been recognized. When each lower-level ECU 20 stores product recognition completed in the storage device 22, it determines that the product has been recognized, and proceeds to step S22. Further, when each lower-level ECU 20 does not store the product recognition completed in the storage device 22, it proceeds to step S21 without determining that the product has been recognized.

In step S21, a product recognition request is transmitted. A lower-level ECU 20 that has not been product-recognized transmits a product-recognition request via the communication line 30 .

In step S22, it is determined whether or not a mounted product response request has been received. Each lower ECU 20 advances to step S23 if it determines that it has received a mounted product response request from the higher ECU 10, and terminates the flow chart of FIG. 3 if it does not determine that it has received a mounted product response request.

In step S23, after waiting for a certain period of time, the mounted product response is transmitted (transmitting step). Each of all the subordinate ECUs 20 waits for a certain period of time and then transmits the onboard product response via the communication line 30 in order to synchronize with the other subordinate ECUs 20 and transmit the onboard product response. Therefore, as described above, all lower-level ECUs 20 transmit mounted product responses including product information signals at the same timing. In the example of FIG. 5, each lower ECU 20 transmits the mounted product response in the second frame.

For example, when LIN is adopted as the communication protocol, each lower ECU 20 synchronizes the clock by performing its own clock correction based on the reference clock of the sync byte field in the header transmitted by the upper ECU 10 . The timing for responding to the header is fixed. Therefore, each lower ECU 20 can synchronize the timing of transmitting the mounted product response.

Further, when CXPI is adopted as the communication protocol, all the lower ECUs 20 superimpose data on the clock that the upper ECU 10 always supplies to the communication line 30, thereby synchronizing the clock. Also, CXPI has a predetermined timing for responding to the header, as in the case of LIN. Therefore, each lower ECU 20 can synchronize the timing of transmitting the mounted product response.

In step S24, it is determined whether or not a mounted product response request has been received. Each lower-level ECU 20 determines again whether or not it has received a mounted product response request. If the host ECU 10 fails to receive the mounted product response due to noise or synchronization failure of communication, the host ECU 10 transmits the mounted product response request again. Therefore, each lower-level ECU 20 confirms again whether or not it has received the response request for the installation product after transmitting the response for the installation product. However, the present disclosure may omit step S24.

After that, each lower ECU 20 receives the product recognition completion via the communication line 30 in step S25. Then, each lower-level ECU 20 stores the received product-recognized information in the storage device 22 in step S26.

<Processing operation: ID setting processing>
An ID setting process, which is an example of a method of setting identification information in the upper ECU 10 and each lower ECU 20, will now be described with reference to FIGS. 8 and 9. FIG. 8 and 9 can also be said to be an identification information setting process for setting the identification information of each lower ECU 20. FIG. Note that the ID setting process is not limited to the one described below.

The host ECU 10 starts the process shown in the flowchart of FIG. 8 when the vehicle is powered on. Similarly, each lower ECU 20 starts the process shown in the flowchart of FIG. 9 when the vehicle power is turned on. Each lower ECU 20 performs the same processing. Therefore, one sub-ECU 20 will be exemplified for explanation.

First, the processing operation of the host ECU 10 will be described with reference to FIG. In step S30, an ID setting determination request is transmitted to all subordinate ECUs. By transmitting an ID setting determination request, the upper ECU 10 requests the lower ECU 20 to determine whether the ID can be set.

In step S31, it is determined whether or not an ID setting request has been received. When the upper ECU 10 receives an ID setting request from the lower ECU 20, the process proceeds to step S32. On the other hand, if the upper ECU 10 does not receive an ID setting request from the lower ECU 20, the flowchart of FIG. 8 is terminated. Further, the host ECU 10 shifts to the normal communication mode after completing the flow chart of FIG.

Note that the present disclosure can also omit steps S30 and S31. In this case, the host ECU 10 performs steps S32 to S44 each time the vehicle is powered on. Thereby, the processing of the upper ECU 10 and the lower ECU 20 can be reduced. Also, the upper ECU 10 can reliably set the selectable ID of the lower ECU 20 .

In step S32, a selectable ID and a selection command are transmitted to all subordinate ECUs (transmitting step). The upper ECU 10 transmits a selectable ID and a selection command to all the lower ECUs 20 connected to the communication line 30 in order to select a selectable ID. At this time, the host ECU 10 transmits a selectable ID and a selection command for each selectable ID. That is, the host ECU 10 transmits the selectable ID and the selection command via the communication line 30 with each selectable ID as the destination. As a result, the upper ECU 10 causes each lower ECU 20 to select one of all selectable ID1 to ID15.

In step S33, an ID return request is transmitted to all lower-level ECUs (reply request step). The upper ECU 10 transmits an ID reply request to all the lower ECUs 20 connected to the communication line 30 in order to return the selected selection ID. At this time, the host ECU 10 transmits an ID return request for each selectable ID. That is, the host ECU 10 transmits an ID reply request via the communication line 30 to each selectable ID as a destination. In other words, the host ECU 10 transmits ID reply requests one by one for all selectable ID1 to ID15. As a result, the upper ECU 10 individually returns the selection ID to each lower ECU 20 .

In step S34, the selection ID and product information are received. The upper ECU 10 receives reply information including the selection ID and the product information PI from all the lower ECUs 20 . At this time, the upper ECU 10 receives the selection ID and the product information PI individually from each lower ECU 20 . As described above, each selection ID is a selectable ID selected by each lower ECU 20 . The selection ID and product information PI correspond to reply information. The reply information should include at least the selection ID and the product information PI. Therefore, the reply information may contain other information in addition to the selection ID and the product information PI. Hereinafter, the selection ID and the product information PI are collectively referred to as reply information.

However, a plurality of lower-level ECUs 20 may select the same selectable ID. In this case, the plurality of lower-level ECUs 20 that have selected the same selectable ID simultaneously transmit reply information in response to ID reply requests addressed to the same destination (selectable ID). Communication collision occurs when a plurality of lower-level ECUs 20 simultaneously transmit reply information. That is, communication collision corresponds to communication collision of reply information. Therefore, the host ECU 10 performs step S35, which will be described later.

In step S35, it is determined whether or not there is communication conflict (collision determination step). The higher-level ECU 10 determines whether or not there is a communication conflict based on the presence or absence of reply information in response to an ID reply request transmitted with a selectable ID as a destination. The higher-level ECU 10 determines that there is communication conflict when reply information cannot be received in response to the ID reply request, and determines that there is no communication conflict when reply information is received in response to the ID reply request. It can be said that the higher-level ECU 10 can recognize selectable IDs that are not in communication conflict based on the presence or absence of reply information.

If the host ECU 10 does not determine that there is a communication collision, the process proceeds to step S36. If the host ECU 10 determines that there is a communication collision, the process proceeds to step S38. In other words, the upper ECU 10 proceeds to step S38 if it determines that even one reply from the lower ECU 20 conflicts, and proceeds to step S36 if it determines that there is no conflict.

It should be noted that the reply information received in response to the ID reply request can be regarded as the reply information that was not determined as communication collision. Therefore, the reply information received in response to the ID reply request corresponds to non-collision information.

In step S38, it is determined whether or not there is a lower ECU that has not collided. If even one piece of reply information is received in response to the all-ID reply request, the upper ECU 10 determines that there is a lower ECU that is not in communication collision, and proceeds to step S39. On the other hand, if the upper ECU 10 has not received any reply information in response to the all-ID return request, it determines that there is no lower ECU 20 that is not in communication collision, and proceeds to step S41.

In step S39, ID registration of the non-collision SECU is performed (storage step). A non-collision SECU is a subordinate ECU 20 that has not caused a communication collision. That is, the non-collision SECU is the lower ECU 20 that has successfully transmitted the reply information to the upper ECU 10 . The non-collision SECU is the subordinate ECU 20 that selects a selectable ID that does not overlap with other subordinate ECUs 20 from all selectable ID1 to ID15. The non-collision SECU corresponds to a non-collision node.

If the reply information can be received, there is one non-collision SECU that has sent the selection ID. Therefore, the host ECU 10 performs ID registration of the non-collision SECU by registering (storing) the selection ID included in the received reply information in the storage device 12 . Further, when performing ID registration, the host ECU 10 associates and stores the selection ID and the product information PI received together with the selection ID. Thereby, the host ECU 10 can determine which selection ID corresponds to which product (product information PI). In the example of FIG. 1, the host ECU 10 associates and stores the selection ID2 (selectable ID2) and the product information PI2. Note that the selection ID registered in step S39 can also be said to be a registered ID. The storage step can also be called a registration step or a registration process.

Thereby, the upper ECU 10 can recognize that the lower ECU 20 having a one-to-one relationship with the selection ID exists. It can also be said that the upper ECU 10 can recognize that the selected ID registered in step S39 and the lower ECU 20 that transmitted the selected ID have a one-to-one relationship.

In step S40, the ID setting completion is notified to the non-collision SECU. The upper ECU 10 transmits completion information indicating completion of ID setting to the lower ECU 20 that has transmitted the registered ID. At this time, the host ECU 10 transmits the completion information via the communication line 30 to the registered ID as a destination. Thereby, the lower ECU 20 that has transmitted the registered ID can receive the completion information. In this way, the host ECU 10 notifies the non-collision SECU of the completion of ID setting.

In step S41, the selectable ID and selection command are resent to the collision SECU. The conflict SECU is the lower ECU 20 that is causing the communication conflict. In other words, the collision SECU is the lower ECU 20 that has not been able to transmit the reply information to the higher ECU 10 . The collision SECU is the subordinate ECU 20 that has selected a selectable ID duplicated with other subordinate ECUs 20 from all selectable ID1 to ID15. Therefore, if the higher-level ECU 10 fails to receive the reply information, it means that a plurality of lower-level ECUs 20 have selected the destinations (selectable IDs) of the ID reply request requesting the reply information. A selectable ID selected by a plurality of lower-level ECUs 20 can be said to be a duplicate ID.

Also, in step S41, the transmission target of the selection command is different from that in step S33. The object of transmission in step S41 is the collision SECU. Note that the transmission target in step S42 is also the collision SECU. Also, the transmission source in step S43 is the collision SECU.

The host ECU 10 transmits the selectable ID and the selection command via the communication line 30 with the duplicate ID as the destination. That is, the host ECU 10 transmits a selectable ID and a selection command via the communication line 30 for each duplicate ID. The selectable ID here is a selectable ID that has not been registered in step S39. As a result, the host ECU 10 causes each collision SECU to select one of a plurality of unregistered selectable IDs.

In other words, when a plurality of lower ECUs 20 have selected the same selectable ID, the upper ECU 10 can reselect the selectable ID. That is, even if each lower ECU 20 selects the same selectable ID as another lower ECU 20, it can select a selectable ID again.

In step S42, an ID reply request is transmitted to the collision SECU. The host ECU 10 transmits an ID return request to each collision SECU connected to the communication line 30 in order to return the selected selection ID. At this time, the host ECU 10 transmits an ID reply request via the communication line 30 with the duplicate ID as the destination. That is, the host ECU 10 transmits an ID reply request via the communication line 30 for each duplicate ID. As a result, the host ECU 10 individually returns the selection ID to each of the collision SECUs 20 .

In step S43, the selection ID and product information are received. The host ECU 10 receives the selection ID and product information PI from each collision SECU. At this time, the host ECU 10 receives the selection ID and the product information PI individually from each collision SECU 20 . Step S44 is similar to step S35.

In step S36, ID registration is performed (storage step). In step S37, the completion of ID setting is notified. As in steps S39 and S40, the host ECU 10 performs registration processing and notifies completion of ID setting. However, in step S36, the host ECU 10 registers the unregistered selection ID as a registration target. In step S37, the host ECU 10 transmits completion information to the selected ID registered in step S36.

Next, the processing operation of the lower ECU 20 will be described with reference to FIG.

In step S50, it is determined whether or not an ID setting determination request has been received. The lower ECU 20 determines whether or not it has received an ID setting determination request addressed to itself, which is transmitted from the higher ECU 10 . If the lower ECU 20 determines that it has received the ID setting determination request, it proceeds to step S51. If the subordinate ECU 20 does not determine that it has received the ID setting determination request, it terminates the flowchart of FIG. Further, if the lower ECU 20 does not determine that it has received the ID setting determination request, it shifts to the normal communication mode.

In step S51, an ID setting request is transmitted. The lower ECU 20 transmits an ID setting request via the communication line 30 .

In step S52, it is determined whether or not a selectable ID and a selection command have been received. The lower ECU 20 determines whether or not it has received a selectable ID and a selection command addressed to itself, which are transmitted from the upper ECU 10 . If the lower ECU 20 determines that it has received the selectable ID and the selection command, it proceeds to step S53. If the subordinate ECU 20 does not determine that the selectable ID and the selection command have been received, the subordinate ECU 20 repeatedly executes step S52.

In step S53, an ID is selected (selection step). The lower ECU 20 selects an arbitrary selectable ID from all selectable ID1 to ID15 received from the higher ECU 10 . In other words, the lower ECU 20 randomly selects one selectable ID from all selectable ID1 to ID15. More specifically, when the subordinate ECU 20 receives all selectable ID1 to ID15 and a selection instruction, it selects one selectable ID from all selectable ID1 to ID15.

Note that the collision SECU selects the same selectable ID as the other lower-level ECUs 20 . Therefore, when the host ECU 10 executes step S41, only the collision SECU selects selectable IDs. At this time, the collision SECU again selects one selectable ID from the selectable IDs that have not been registered in the registration process. Note that the case where the host ECU 10 executes step S41 is the same as the case where it is determined that there is a communication collision.

Further, according to the present disclosure, when it is determined that there is a communication collision, all lower-level ECUs 20 may select selectable IDs again (selection step). In this case, it is possible to prevent the processing of the host ECU 10 from becoming complicated.

In step S54, it is determined whether or not an ID reply request has been received. The lower ECU 20 determines whether or not it has received an ID return request addressed to itself, which is transmitted from the higher ECU 10 . The lower ECU 20 uses the selection ID selected in step S53 to determine whether or not it has received an ID return request addressed to itself. When the lower ECU 20 determines that it has received the ID return request, it proceeds to step S55. If the lower ECU 20 does not determine that it has received the ID reply request, it repeats step S54. In other words, the lower ECU 20 waits for an ID return request from the upper ECU 10 and proceeds to step S55.

In step S55, the selection ID and product information are returned (reply step). When receiving the ID return request, the lower ECU 20 returns the selection ID and the product information PI. The subordinate ECU 20 returns the selection ID selected in step S53 and the product information PI stored in the storage device 22 . Also, the lower ECU 20 transmits the selection ID and the product information PI to the upper ECU 10 via the communication line 30 .

Thus, in this embodiment, when an ID return request is received, an example is adopted in which the selection ID and the product information PI are returned. However, the present disclosure is not so limited. The lower ECU 20 may transmit the selected ID and the product information PI to the upper ECU 10 when one selectable ID is selected from the selectable ID1 to ID15. In this case, step S33 may be omitted.

In step S56, it is determined whether or not the completion of ID setting has been notified. The lower ECU 20 determines whether it has received the completion information addressed to itself, which is transmitted from the higher ECU 10 . The lower ECU 20 uses the selection ID selected in step S53 to determine whether or not the completion information addressed to itself has been received. When the lower ECU 20 receives the completion information, it considers that the ID setting completion has been notified, and terminates the flowchart of FIG. If the lower ECU 20 has not received the completion information, it considers that the ID setting completion has not been notified and returns to step S52.

<effect>
In this way, according to the lower node recognition method, when a connection signal and a non-connection signal are assigned to the same bit in different product information signals transmitted in synchronization, the upper ECU 10 receives the connection signal. By receiving a plurality of product information signals transmitted in synchronism, the higher-level ECU 10 knows the bit that received the connection signal. Therefore, the upper ECU 10 can recognize the product of the lower ECU 20 connected to the communication line 30 from the product information PI associated with the bit of the received connection signal in the bit assignment 122 . Therefore, the lower node recognition method can shorten the recognition time of the lower ECUs 20 than the configuration in which the plurality of lower ECUs 20 transmit the product information signal at different timings.

Further, according to the lower node recognition method (method of setting identification information), the upper ECU 10 transmits all selectable ID1 to ID15, and each lower ECU 20 transmits the selection ID selected from all selectable ID1 to ID15 as the product information. It is transmitted to the host ECU 10 together with the PI. In the lower node recognition method, the higher ECU 10 can recognize the lower ECU 20 by associating and storing the selection ID received from the lower ECU 20 and the product information PI. Further, it can be said that the lower node recognition method can automatically recognize the lower ECU 20 when the lower ECU 20 is added, deleted, or replaced with respect to the in-vehicle network 100 .

Therefore, the lower node recognition method does not require a dedicated device for setting identification information between the communication line 30 and the lower ECU 20 . Therefore, the lower node recognition method can recognize the lower ECU 20 without increasing the number of parts.

In this embodiment, an example in which the higher-level ECU 10 determines communication collision is adopted. However, the present disclosure is not limited to this, and each lower ECU 20 may determine communication collision. In this case, each lower ECU 20 that has determined that there is a communication conflict may exclude non-conflicting selectable IDs from selection candidates when selecting selectable IDs.

The preferred embodiments of the present disclosure have been described above. However, the present disclosure is by no means limited to the above embodiments, and various modifications are possible without departing from the scope of the present disclosure.

(Second embodiment)
The second embodiment differs from the first embodiment in the processing operations of the upper ECU 10 and the lower ECU 20 . The present embodiment differs from the first embodiment in that the higher-level ECU 10 transmits a mounted product response request for each product system. Further, the present embodiment is different from the first embodiment in that the subordinate ECU 20 transmits a controlled product response in response to an on-board product response request of the corresponding system. The configurations of the in-vehicle network 100, the upper ECU 10, and the lower ECU 20 are the same as in the first embodiment.

However, the information stored in the upper ECU 10 and the lower ECU 20 differs from that in the first embodiment. Products mounted on vehicles can be classified into multiple systems. The product system includes, for example, an engine system, a hybrid (HV) system, and a body system. System information indicating the product system of each lower ECU 20 is pre-stored in the non-volatile memory of the storage device 22 .

In the example of FIG. 12, system information indicating that SECU1 and SECU2 are engine systems is stored in the storage device 22 . System information indicating that the SECU 3 is an HV system is stored in the storage device 22 . System information indicating that SECUX is a body system is stored in the storage device 22 . On the other hand, the host ECU 10 has a plurality of system information stored in advance in the non-volatile memory of the storage device 12 .

Here, processing operations of the upper ECU 10 and the lower ECU 20 will be described. The host ECU 10 starts the process shown in the flowchart of FIG. 10 when the vehicle is powered on. Similarly, each lower ECU 20 starts the process shown in the flowchart of FIG. 11 when the vehicle power is turned on. In FIG. 10, the same step numbers are assigned to the same processes and determinations as in FIG. In addition, in FIG. 11, the same step numbers are given to the same processes and determinations as in FIG.

In step S11a, the host ECU 10 transmits a mounted product response request including system information. In this manner, the upper ECU 10 causes the lower ECU 20 to transmit the mounted product response for each system of the product.

Note that the host ECU 10 has a preset order for transmitting the mounted product response request for each system. Here, it is set so that the mounted product response request is transmitted in the order of the engine system, the HV system, and the body system.

In step S15, it is determined whether or not all systems have been recognized. The host ECU 10 determines whether product recognition has been completed for all systems. If the host ECU 10 does not determine that all systems have been recognized, it returns to step S11a, and if it determines that all systems have been recognized, the flowchart of FIG. 10 ends.

For example, each time the host ECU 10 transmits a mounted product response request including system information, it stores that recognition of the host ECU 20 (product) of the system has been completed. Thereby, the host ECU 10 can determine whether or not product recognition has been completed for all systems.

Each lower ECU 20 determines whether or not it is a corresponding system in step S22a. Each subordinate ECU 20 determines whether or not it is a corresponding system based on the system information stored in its own storage device 22 and the system information included in the mounted product response request.

Each lower ECU 20 determines that it is the corresponding system when the system information included in the mounted product response request matches the system information stored in its own storage device 22 . When the system information included in the mounted product response request does not match the system information stored in its own storage device 22, each lower ECU 20 determines that the system is not the corresponding system. When each lower ECU 20 determines that it is the corresponding system, it proceeds to step S23, and when it determines that it is not the corresponding system, it returns to step S22. Therefore, in step S23, only the subordinate ECU 20 determined as the corresponding system transmits the mounted product response.

In the example of FIG. 12, the higher-level ECU 10 transmits a mounted product response request including the system information of the engine system in the first frame. Therefore, in the second frame, only SECU1 and SECU2 transmit the installed product response.

Similarly, the higher-level ECU 10 transmits a mounted product response request including HV system information in the third frame. Therefore, in the 4th frame, only SECU3 transmits the mounted product response. The host ECU 10 transmits a mounted product response request including body system information in the fifth frame. Therefore, in the 6th frame, only SECUX sends an on-board product response. SECUX is a body-type product. Note that the number of subordinate ECUs 20 in each system is not limited to the above example.

The subordinate node recognition method of the second embodiment can produce the same effect as the first embodiment. In addition, since the amount of data that can be transmitted by the communication protocol is limited, it may not be possible to manage the product information of all the lower nodes of the vehicle with one bit assignment. However, in the lower node recognition method of the second embodiment, it is possible to recognize the products of all vehicles by confirming each system such as an engine. It should be noted that the host ECU 10 may transmit an on-board product response request including a plurality of system information. In this case, the subordinate ECUs 20 of a plurality of systems simultaneously transmit the mounted product response.

(Modification 1)
The host ECU 10 may not have system information. In this case, for all lower-level ECUs 20, the order of transmission of mounted product responses to mounted product response requests is determined for each system. In addition, it can be said that each lower-level ECU 20 has a predetermined frame for transmitting the mounted product response. In the example of FIG. 13, the transmission order of the mounted product response is determined so that the engine system is the first and the HV system is the second. The subordinate ECUs 20 that transmit in one frame may be products of a plurality of systems (subordinate ECUs 20).

In this way, each lower-level ECU 20 transmits the mounted product response in a time division manner. Therefore, the modified example can recognize the lower ECU 20 earlier than the second embodiment.
(Modification 2)

<Processing operation: ID setting processing>
Next, the processing operation of the host ECU 10 in the modified example 2 will be described with reference to FIGS. 14 to 17. FIG. In modification 2, the processing operation when YES is determined in step S35 is different from that in the first embodiment. In other words, Modification 2 differs from the first embodiment in the method of reselecting selectable IDs. The configurations of the upper ECU 10, the lower ECU 20, and the in-vehicle network 100 are the same as in the first embodiment.

In step S60, first collision processing is performed. The first collision processing will be described with reference to the flowchart of FIG. 15 . In step S601, it is determined whether or not it is a non-collision SECU. If the host ECU 10 determines that the vehicle is the non-collision SECU, the process proceeds to step S602, and if not, the process proceeds to step S605.

Note that the upper ECU 10 determines that the lower ECU that has sent the reply information in response to the ID return request is the non-collision SECU. Also, the host ECU 10 recognizes the selection ID included in the received reply information as the destination of the non-collision SECU.

On the other hand, the higher-level ECU 10 determines that the lower-level ECU that has not sent reply information in response to the ID return request is a collision SECU. Also, the host ECU 10 recognizes the destination (selectable ID) of the ID reply request when requesting the reply information that could not be received as the destination of the collision SECU.

Step S602 is similar to step S39. That is, the host ECU 10 associates and stores the selection ID included in the non-collision information and the product information PI (storage step). Step S603 is similar to step S40.

In step S604, a communication prohibition request is transmitted (communication prohibition step). The upper ECU 10 transmits a communication prohibition request to the lower ECU 20 that has transmitted the registered selection ID (registered ID). The subordinate ECU 20 that has transmitted the registered ID is the non-collision SECU. Therefore, the host ECU 10 prohibits the non-collision SECU from communicating. At this time, the host ECU 10 transmits a communication prohibition request via the communication line 30 to the registered ID as a destination.

Thereby, the non-collision SECU 20 receives the communication prohibition request. A non-collision SECU that has received a communication prohibition request does not, for example, transmit a request addressed to itself even if it receives the request.

In step S605, the selection command is resent to the collision SECU (retransmitting step). In step S605, as in step S41, the selection command is resent only to the collision SECU. The host ECU 10 transmits a selection command via the communication line 30 using the selectable ID that is the destination of the collision SECU. Also, the host ECU 10 commands selection of one selectable ID from all selectable ID1 to ID15.

Therefore, the collision SECU reselects one selectable ID from all selectable ID1 to ID15. Among all selectable ID1 to ID15, some have already been registered by the host ECU 10. FIG. Therefore, when the collision SECU selects a selectable ID again, it may select an already registered selectable ID. A registered selectable ID is also referred to as a registered ID.

Note that in step S605, unlike step S41, the selectable ID need not be resent. In other words, the host ECU 10 causes each collision SECU to select one of all selectable ID1 to ID15 that have already been transmitted.

Here, it returns to the flowchart of FIG. Step S61 is the same as step S33. Therefore, the upper ECU 10 transmits an ID reply request to all the lower ECUs 20 connected to the communication line 30 in order to return the selected selection ID. However, some lower-level ECUs 20 have received the communication prohibition request in step S604. Therefore, the lower ECU 20 that has received the communication prohibition request does not return the selection ID and the product information PI even if it receives the ID return request.

In step S62, it is determined whether or not there is communication collision. The host ECU 10 determines whether or not there is a communication conflict, as in step S35. Then, if the host ECU 10 does not determine that there is a communication collision, the process proceeds to step S64. If the host ECU 10 determines that there is a communication collision, the process proceeds to step S62.

In step S63, a second collision process is performed. The second collision processing will be described with reference to the flowchart of FIG. 16 . Step S631 is the same as step S601. Step S637 is similar to step S604. Step S638 is similar to step S605.

In step S632, it is determined whether or not a registered ID has been selected. The host ECU 10 determines whether or not the non-collision SECU has selected the registered ID based on the received selected ID and registered ID. A non-collision SECU that has transmitted a selection ID of registered IDs is referred to as a selected SECU. On the other hand, a non-collision SECU that has sent a selection ID that is not a registered ID is referred to as a non-selection SECU. That is, the host ECU 10 distinguishes between the selected SECU and the non-selected SECU depending on whether or not there is a registered ID that is the same as the received selected ID.

Therefore, the selection ID transmitted by the selected SECU has already been selected by another lower-level ECU 20, although there is no communication collision. On the other hand, the selection ID transmitted by the non-selection SECU is not in communication conflict and is not selected by other lower-level ECUs 20 .

When the host ECU 10 determines that the received selection ID is among the registered IDs, it considers that the registered ID is selected, and proceeds to step S635. That is, the host ECU 10 determines the non-collision SECU that has transmitted the selection ID as the selected SECU.

Further, when the host ECU 10 determines that the received selection ID is not among the registered IDs, it considers that the registered ID is not selected and proceeds to step S633. That is, the host ECU 10 determines the non-collision SECU that has transmitted the selection ID as the non-selection SECU.

In step S633, ID registration of non-selected SECUs is performed (storage step). The host ECU 10 performs ID registration in the same manner as in step S602. It can be said that the host ECU 10 registers the IDs of the non-selected SECUs by registering selection IDs that are not duplicated and are not registered IDs.

In step S634, the non-selected SECUs are notified of the completion of ID setting. The host ECU 10 transmits completion information in the same manner as in step S603. The destination of the completion information here is the non-selected SECU.

In step S635, another idle ID is registered in the selected SECU (unselected storage step). A free ID is a selectable ID that is not stored or registered in association with the product information PI.

The host ECU 10 registers another idle ID in the selected SECU. That is, the host ECU 10 associates the product information PI received from the selected SECU with the empty ID and stores them in the storage device 12, thereby registering another empty ID in the selected SECU. In other words, if the selection ID included in the non-collision information has already been stored in association with the product information PI after the retransmission process, the higher-level ECU 10 stores the product information included in the non-collision information and the free ID. and are stored in association with each other. In this way, with respect to the selected SECU, the product information PI is associated with the idle ID selected by the host ECU 10 rather than the selected ID selected by the selected SECU.

In step S636, the ID setting completion is notified to the non-collision SECU. The host ECU 10 transmits completion information in the same manner as in step S603. The non-collision SECU here is the non-select SECU. Also, the host ECU 10 transmits the completion information to the empty ID as a destination.

Here, it returns to the flowchart of FIG. In step S64, it is determined whether or not there is a lower ECU whose registered ID has been reselected. If the upper ECU 10 determines that there is a lower ECU whose registered ID has been reselected, the process proceeds to step S65; otherwise, the process proceeds to step S16.

In step S65, a third collision process is performed. The third collision processing will be described with reference to the flowchart of FIG. 17 . Step S651 is the same as step S632. Step S652 is the same as step S633. Step S653 is the same as step S634. Step S654 is similar to step S635. Step S655 is the same as step S636.

<effect>
The subordinate node recognition method of Modification 2 can achieve the same effects as those of the first embodiment. In the subordinate node recognition method, when the collision SECU selects a selectable ID again, it selects a selectable ID from all selectable ID1 to ID15. Therefore, in the lower node recognition method, the number of selectable IDs to be selected does not decrease even when selection is made again. That is, in the lower node recognition method, the number of selectable IDs to be selected for reselection is the same as the number of selectable IDs to be selected for initial selection. Therefore, the lower node recognition method can shorten the time until the selection ID is registered as compared with the first embodiment.

Although the present disclosure has been described in accordance with embodiments, it is understood that the present disclosure is not limited to such embodiments or structures. The present disclosure also includes various modifications and modifications within the equivalent range. Additionally, while various combinations and configurations are shown in this disclosure, other combinations and configurations, including only one element, more, or less, are within the scope and spirit of this disclosure. is to enter.

DESCRIPTION OF SYMBOLS 10... Upper ECU, 11... Arithmetic device, 12... Storage device, 121... ID storage area, 122... Bit assignment, 13... Communication device, 20... Lower ECU, 21... Arithmetic device, 22... Storage device, 221... Selection ID , 23... communication device, 30... communication line, 100... in-vehicle network

Claims (3)

Said subordinate node in a network comprising: a communication line; an upper node connected to said communication line; and a plurality of lower nodes which are electronic control devices connected to said communication line for transmitting and receiving communication frames with said upper node A method of recognizing a node, comprising:
said upper node has product group information in which product information indicating products of each lower node is associated with each of a plurality of divided areas in said communication frame;
Each lower node assigns a connection signal indicating that it is connected to the communication line to the area associated with the product information indicating the product of itself as the communication frame, which transmits the product information signal to which the connection signal is assigned;
a request step (S11, S11a) in which the upper node transmits a request signal to the plurality of lower nodes connected to the communication line to request transmission of the product information signal;
a transmitting step (S23) in which, when each of the plurality of lower nodes receives the request signal, transmits the product information signal in synchronization with the other lower nodes;
The upper node receives the plurality of product information signals transmitted in the transmitting step, and based on the received plurality of product information signals and the product group information, the lower node connected to the communication line a recognition step (S12, S13) for recognizing the product of the node,
In the recognition step, if the connection signal and the non-connection signal are assigned to the same region in the different product information signals transmitted in the transmission step, the connection signal is received and the product group information is received. a lower node recognition method for recognizing the product of the lower node connected to the communication line from the product information associated with the area of the received connection signal. Each lower node has system information indicating the product system in which the product is included,
The upper node has a plurality of the system information indicating different product systems,
In the request step, the upper node transmits the system information in addition to the request signal for each system information,
2. The lower node recognition method according to claim 1, wherein said plurality of lower nodes transmit said product information signal in said transmission step upon receiving said request signal and said system information possessed by itself. Each lower node has a predetermined order of transmission of the product information signal for each product line including the product of itself,
2. The method according to claim 1, wherein in said transmitting step, each of said plurality of lower nodes receives said request signal and, when it comes to said transmission order of itself, synchronizes with said other lower nodes and transmits said product information signal. The subordinate node recognition method described.

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