Relay device, communication system, and processing method

Abstract

A relay device relays communication. The relay device includes a reception unit that receives communication data from a communication device, a storage unit that stores the communication data received by the reception unit, and a processing unit that performs processing. A first period and a second period are alternately set. The processing unit changes the total number of the first period and the second period included in a next prescribed period each time a prescribed period including the first period and the second period elapses. The processing unit determines whether or not communication data is stored in the storage unit. The processing unit determines a period to which a communication determination time point for which the determination is made belongs between the first period and the second period in a case where it is determined that the communication data is stored in the storage unit.

Description

Technical Field

[0001] This disclosure relates to relay devices, communication systems, and processing methods.

[0002] This application claims priority based on Japanese Application No. 2021-116631, filed on July 14, 2021, and invokes all the contents recorded in the aforementioned Japanese application. Background Technology

[0003] Patent Document 1 discloses a communication system in which a communication device transmits data to another communication device via a relay device. The communication device transmits priority data that needs to reach the other communication device within a short period. Upon receiving priority data from the communication device, the relay device determines whether to transmit the received priority data. An allowable period and a prohibition period are alternately and repeatedly set; during the allowable period, the transmission of priority data is permitted, and during the prohibition period, the transmission of priority data is prohibited. If the time point at which the relay device determines whether to transmit priority data falls within the allowable period, it transmits the received priority data during the allowable period.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: International Publication No. 2020 / 136843 Summary of the Invention

[0007] One aspect of this disclosure relates to a relay device for relaying communication, wherein the relay device comprises: a receiving unit for receiving communication data from a communication device; a storage unit for storing the communication data received by the receiving unit; and a processing unit for performing processing, alternately setting a first period and a second period, wherein each time a predetermined period including the first period and the second period passes, the processing unit changes the total number of the first period and the second period included in the next predetermined period, the processing unit determines whether the communication data is stored in the storage unit, and if the processing unit determines that the communication determination time point has been determined, it determines the period to which the determined communication determination time point belongs in the first period and the second period.

[0008] One aspect of the communication system disclosed herein includes: a communication device for transmitting data; and a relay device for receiving data from the communication device and transmitting the received data. The communication device has a communication processing unit that performs processing and instructs the relay device to transmit communication data. The relay device includes: a relay receiving unit for receiving the communication data from the communication device; a relay storage unit for storing the communication data received by the relay receiving unit; and a relay processing unit that performs processing, alternately setting a first period and a second period. Whenever a predetermined period including the first period and the second period passes, the relay processing unit changes the total number of the first period and the second period included in the next predetermined period. The relay processing unit determines whether the communication data is stored in the relay storage unit. If the relay processing unit determines that the communication data is stored in the relay storage unit, it determines the period to which the determined communication determination time point belongs within the first period and the second period.

[0009] One aspect of this disclosure relates to a processing method for a relay device, the relay device comprising: a receiving unit for receiving communication data from a communication device; and a storage unit for storing the communication data received by the receiving unit, the relay device performing communication relay, wherein a computer performs the following steps: whenever a predetermined period comprising alternately set first and second periods has elapsed, changing the total number of the first and second periods included in the next predetermined period; determining whether the communication data is stored in the storage unit; and if it is determined that the communication determination time point in the storage unit belongs to the period of the first and second periods.

[0010] Furthermore, this disclosure can be implemented not only as a relay device with such a characteristic processing unit, but also as a processing method that includes the characteristic processing as a step, or as a computer program for causing a computer to execute the step. Additionally, this disclosure can be implemented as a semiconductor integrated circuit that implements part or all of the relay device, or as a communication system that includes the relay device. Attached Figure Description

[0011] Figure 1 This is a block diagram showing the main structural components of the communication system in Implementation 1.

[0012] Figure 2 This is an explanatory diagram of the relay method of the relay device.

[0013] Figure 3 This is an illustration of the actions performed within the transmit buffer.

[0014] Figure 4 This is an explanatory diagram illustrating the relay frame determination method performed by the relay device.

[0015] Figure 5 It is a graph that shows the relationship between relay determination time points and actions related to relay frames.

[0016] Figure 6 This is an explanatory diagram illustrating the method for determining communication frames by a relay device.

[0017] Figure 7 It is a graph that shows the relationship between communication decision points and actions related to communication frames.

[0018] Figure 8 This is a block diagram showing the main structural components of a relay device.

[0019] Figure 9 This is an explanatory diagram of the content of the pattern data.

[0020] Figure 10 It is a chart that represents the content of the target data.

[0021] Figure 11 It is a block diagram showing the main structural components of the vehicle-mounted equipment.

[0022] Figure 12 This is a flowchart illustrating the initial setup steps performed by the relay device and the on-board equipment.

[0023] Figure 13 This is a flowchart illustrating the initial setup steps performed by the relay device and the on-board equipment.

[0024] Figure 14 It is a timing diagram that outlines the method for determining the overall duration of onboard equipment.

[0025] Figure 15 This is an explanatory diagram illustrating the method for determining the scope.

[0026] Figure 16 This is an explanatory diagram illustrating the method for determining the overall period when there are two ranges as to which the scope belongs.

[0027] Figure 17 This is a flowchart illustrating the steps of the period change processing corresponding to the communication queue of the transmit buffer.

[0028] Figure 18 This is a flowchart illustrating the steps involved in the communication frame relay processing of the transmit buffer.

[0029] Figure 19 This is a flowchart representing the steps involved in determining the processing time of the onboard equipment.

[0030] Figure 20 This is a flowchart illustrating the steps involved in relay frame transmission processing for onboard equipment.

[0031] Figure 21 This is an explanatory diagram of the content of the pattern data in Implementation Method 2.

[0032] Figure 22 This is a flowchart illustrating the steps of the period notification processing of the transmission buffer in Implementation 3.

[0033] Figure 23 This is a flowchart representing the steps involved in determining the processing time of the onboard equipment.

[0034] Figure 24 This is a flowchart illustrating the initial setup steps performed on the relay device and the vehicle-mounted equipment in Implementation Method 4.

[0035] Figure 25 It is a timing diagram that outlines the method for determining the overall duration of onboard equipment.

[0036] Figure 26 This is a flowchart illustrating the steps of the period change processing corresponding to the communication queue of the transmit buffer.

[0037] Figure 27 This is a flowchart illustrating the steps involved in the communication frame transmission and processing of in-vehicle equipment.

[0038] Figure 28 This is a flowchart illustrating the steps involved in the period adjustment process of the transmit buffer. Detailed Implementation

[0039] [The problem this disclosure aims to solve]

[0040] In cases where it is possible to determine the overall period from when data transmission is indicated in the communication device to the time point at which the data is determined, for example, the communication device can adjust the time point at which the transmission of the indicated priority data is made so that the time point at which the priority data is determined falls within the permissible period. However, Patent Document 1 does not disclose a structure capable of determining the overall period.

[0041] This disclosure was made in view of the above circumstances, and its purpose is to provide a relay device, communication system, and processing method capable of determining the overall period from the transmission of instruction data to the determination time of the data.

[0042] [The Effects of This Disclosure]

[0043] According to the above method, it is possible to determine the entire period from the time the data is sent to the time the data is determined.

[0044] [Description of embodiments of this disclosure]

[0045] First, embodiments of this disclosure will be described. At least some of the embodiments described below may be combined arbitrarily.

[0046] (1) One aspect of the present disclosure relates to a relay device for relaying communication, wherein the relay device comprises: a receiving unit for receiving communication data from a communication device; a storage unit for storing the communication data received by the receiving unit; and a processing unit for performing processing, alternately setting a first period and a second period, wherein each time a predetermined period including the first period and the second period passes, the processing unit changes the total number of the first period and the second period included in the next predetermined period, the processing unit determines whether the communication data is stored in the storage unit, and if the processing unit determines that the communication determination time point has been determined, the processing unit determines the period to which the determined communication determination time point belongs in the first period and the second period.

[0047] (2) In a relay device according to one aspect of the present disclosure, the processing unit changes the total number of each specified period in such a way that the total number of each of a plurality of consecutive specified periods is different, and for the plurality of specified periods, the processing unit changes the position of the boundary within each specified period in such a way that the position of the boundary between the first period and the second period is different.

[0048] (3) In a relay device according to one aspect of the present disclosure, the processing unit changes the total number of each specified period in such a way that the total number contained in each of a plurality of consecutive specified periods is different, and the processing unit repeats the plurality of specified periods multiple times.

[0049] (4) In a relay device according to one aspect of this disclosure, the receiving unit receives communication data from the communication device each time the specified period has elapsed, and the processing unit changes the total number of each specified period in such a way that the total number contained in each of the multiple consecutive specified periods is different. When the multiple specified periods have elapsed, the processing unit determines the range to which the communication determination time point belongs in the specified period based on multiple determination results related to the period, and the processing unit determines the overall period from the time when the communication device instructs the transmission of communication data to the time point of communication determination based on the determined range.

[0050] (5) In a relay device according to one aspect of this disclosure, the receiving unit receives relay data for relaying, stores the received relay data in the storage unit, alternately sets an allowed period and a prohibited period, allows the transmission of the relay data during the allowed period, and prohibits the transmission of the relay data during the prohibited period, the processing unit determines whether the relay data is stored in the storage unit, and when the processing unit determines that the relay data is stored in the storage unit, determines the period to which the determined relay determination time point belongs in the allowed period and the prohibited period, and when the determined period is the allowed period, the processing unit instructs the transmission of the relay data, and the processing unit adjusts the start time point or length of the allowed period based on the determined overall period.

[0051] (6) A communication system according to one aspect of this disclosure includes: a communication device for transmitting data; and a relay device for receiving data from the communication device and transmitting the received data, the communication device having a communication processing unit that performs processing, the communication processing unit instructing the relay device to transmit communication data, the relay device having: a relay receiving unit for receiving the communication data from the communication device; a relay storage unit for storing the communication data received by the relay receiving unit; and a relay processing unit that performs processing, alternately setting a first period and a second period, wherein each time a predetermined period including the first period and the second period passes, the relay processing unit changes the total number of the first period and the second period included in the next predetermined period, the relay processing unit determines whether the communication data is stored in the relay storage unit, and if the relay processing unit determines that the communication determination time point to which the determination is made belongs in the first period and the second period.

[0052] (7) In a communication system according to one aspect of this disclosure, the communication processing unit instructs the relay receiving unit to send communication data whenever the specified period has elapsed. The relay processing unit changes the total number of each specified period in such a way that the total number contained in each of the multiple consecutive specified periods is different. When the multiple specified periods have elapsed, the communication processing unit determines the range to which the communication determination time point belongs in the specified period based on multiple determination results determined by the relay processing unit. Based on the determined range, the communication processing unit determines the overall period from the instruction to send the communication data to the communication determination time point.

[0053] (8) In a communication system according to one aspect of this disclosure, the communication processing unit instructs the transmission of relay data for relaying to the relay receiving unit, the relay storage unit stores the relay data received by the relay receiving unit, and alternately sets an allowable period and a prohibition period, allowing the transmission of the relay data during the allowable period and prohibiting the transmission of the relay data during the prohibition period. The relay processing unit determines whether the relay data is stored in the relay storage unit. If the relay processing unit determines that the relay data is stored in the relay storage unit, it determines the period to which the determined relay determination time point belongs in the allowable period and the prohibition period. If the determined period is the allowable period, the relay processing unit instructs the transmission of the relay data. The communication processing unit determines the transmission instruction time point for instructing the transmission of the relay data based on the determined overall period.

[0054] (9) In a communication system according to one aspect of this disclosure, when the determined period is the first period, the relay processing unit instructs the communication device to send the communication data received by the relay receiving unit; when the determined period is the second period, the relay processing unit discards the communication data received by the relay receiving unit; and when the multiple predetermined periods have elapsed, the communication processing unit determines the range to which the communication determination time point belongs within the predetermined periods based on the multiple reception results of the communication data.

[0055] (10) One aspect of the present disclosure relates to a processing method for a relay device, the relay device comprising: a receiving unit for receiving communication data from a communication device; and a storage unit for storing the communication data received by the receiving unit, the relay device performing communication relay, wherein a computer performs the following steps: whenever a predetermined period comprising alternately set first and second periods has elapsed, changing the total number of the first and second periods included in the next predetermined period; determining whether the communication data is stored in the storage unit; and if it is determined that the communication data is stored in the storage unit, determining the period to which the determined communication determination time point belongs in the first and second periods.

[0056] In the above method, for example, the communication device instructs the transmission of communication data each time a predetermined period elapses. Each time a predetermined period elapses, the relay device changes the total number of the first and second periods included in the next predetermined period. The relay device determines the period to which the communication determination time point of the communication data belongs. Based on the determination results of multiple communication data sets, the communication device or relay device can determine the range to which the communication determination time point of the communication data belongs within the predetermined period. Based on the determined range, the communication device or relay device can determine the entire period from when the communication device instructs the transmission of communication data until the communication determination time point.

[0057] In the above method, for example, the communication device instructs the transmission of communication data each time a predetermined period has elapsed. Regarding the multiple consecutive predetermined periods, the total number of the first period and the total number of the second period are different. After the multiple consecutive predetermined periods have elapsed, the communication device or relay device determines the range to which the communication determination time point of the communication data belongs within the predetermined periods based on the determination results of multiple communication data.

[0058] When the boundaries between multiple consecutive specified periods are consistent, and multiple communication determination time points vary near these consistent boundaries, the period to which each communication determination time point belongs is not fixed within any given specified period. Therefore, the communication device or relay device cannot accurately determine the corresponding range. However, when the locations of the boundaries between multiple consecutive specified periods are different, the communication device or relay device can accurately determine the corresponding range even when the communication determination time points vary.

[0059] In the above method, for example, the communication device instructs the transmission of communication data each time a predetermined period elapses. Each time multiple consecutive predetermined periods elapse, the communication device or relay device determines the range to which the communication determination time point belongs based on the determination results of multiple communication data. The relay device repeats the predetermined period multiple times. Therefore, in the case of a change in the communication determination time point, the communication device or relay device can determine the overall period taking the change into account based on the determined multiple ranges.

[0060] In the above method, for example, the communication device instructs the transmission of communication data each time a predetermined period has elapsed. If the predetermined period has elapsed, the relay device determines the range to which the communication determination time point belongs based on the determination results of multiple communication data. The relay device then determines the overall period based on the determined range.

[0061] In the above method, the relay device adjusts the start time or length of the allowed period based on the determined overall period, for example, in a way that makes the relay determination time point of the relay data belong to the allowed period.

[0062] In the above method, for example, the communication device instructs the transmission of communication data each time a predetermined period has elapsed. If the predetermined period has elapsed, the communication device determines the range to which the communication determination time point belongs based on the determination results of multiple communication data points. The communication device then determines the overall period based on the determined range.

[0063] In the above method, the communication device determines the transmission instruction time point for sending relay data to the relay device based on the overall determined period, for example, in a way that makes the relay determination time point of the relay data fall within the allowed period.

[0064] In the above method, the result of receiving communication data represents the determination result of communication data related to the period. The communication device determines the range to which the communication determination time point belongs based on the received result, and determines the overall period based on the determined range.

[0065] [Details of the embodiments disclosed herein]

[0066] Hereinafter, specific examples of the communication system involved in the embodiments of this disclosure will be described with reference to the accompanying drawings. Furthermore, this disclosure is not limited to these examples, as shown in the claims, and is intended to include all modifications with the same meaning and scope as the claims.

[0067] (Implementation Method 1) <Structure of Communication System>

[0068] Figure 1 This is a block diagram showing the main structural components of the communication system 1 in Embodiment 1. The communication system 1 is mounted on a vehicle M. The communication system 1 includes a relay device 2 and three on-board devices 3a, 3b, and 3c. The on-board devices 3a, 3b, and 3c are, for example, ECUs (Electronic Control Units). Three connectors 2a, 2b, and 2c are connected to the relay device 2. The on-board devices 3a, 3b, and 3c are connected to the connectors 2a, 2b, and 2c in a detachable manner.

[0069] Vehicle-mounted devices 3a, 3b, and 3c function as communication devices. They transmit and receive relay frames for relay purposes. A relay frame is data composed of multiple bits, equivalent to relay data. Relay device 2 receives relay frames from vehicle-mounted devices 3a, 3b, and 3c. When relay device 2 receives a relay frame from vehicle-mounted device 3a, it sends the received relay frame to one of vehicle-mounted devices 3b or 3c. Similarly, when relay device 2 receives a relay frame from vehicle-mounted device 3b, it sends the received relay frame to one of vehicle-mounted devices 3a or 3c. When relay device 2 receives a relay frame from vehicle-mounted device 3c, it sends the received relay frame to one of vehicle-mounted devices 3a or 3b. As described above, relay device 2 relays communication between two of the vehicle-mounted devices 3a, 3b, and 3c.

[0070] Vehicle-mounted devices 3a, 3b, and 3c respectively transmit relay frames containing sensor data or indication data to relay device 2. Sensor data represents the detected values ​​by the sensors. The vehicle M, for example, has a receiving unit for receiving instructions from occupants. Indication data, for example, represents the instructions received by the receiving unit. Indication data, for example, represents an indication of locking or unlocking a door. Upon receiving a relay frame from relay device 2, vehicle-mounted devices 3a, 3b, and 3c perform actions based on the received relay frame.

[0071] Vehicle-mounted devices 3a, 3b, and 3c transmit and receive communication frames to determine the overall period described later. A communication frame is data composed of multiple bits, equivalent to communication data. Relay device 2 receives communication frames from vehicle-mounted devices 3a, 3b, and 3c respectively. When relay device 2 receives a communication frame from vehicle-mounted device 3a, it transmits the received communication frame to vehicle-mounted device 3a. Similarly, when relay device 2 receives a communication frame from vehicle-mounted device 3b, it transmits the received communication frame to vehicle-mounted device 3b. When relay device 2 receives a communication frame from vehicle-mounted device 3c, it transmits the received communication frame to vehicle-mounted device 3c.

[0072] <Operation of Relay Device 2>

[0073] Figure 2 This is an explanatory diagram of the relay method of relay device 2. Relay device 2 has a device storage unit 22 (see reference). Figure 8 ).like Figure 2As shown, the device storage unit 22 includes three receive buffers Ra, Rb, and Rc, and three transmit buffers Ta, Tb, and Tc, serving as storage areas. The relay device 2 writes relay frames received from the vehicle-mounted devices 3a, 3b, and 3c into the receive buffers Ra, Rb, and Rc, respectively. Similarly, the relay device 2 writes communication frames received from the vehicle-mounted devices 3a, 3b, and 3c into the receive buffers Ra, Rb, and Rc, respectively.

[0074] Relay frames, with the target devices 3a, 3b, and 3c, are written to the transmit buffers Ta, Tb, and Tc, respectively. Similarly, communication frames, with the target devices 3a, 3b, and 3c, are written to the transmit buffers Ta, Tb, and Tc, respectively. The relay frames and communication frames represent the target devices.

[0075] Relay device 2 transfers relay frames destined for vehicle-mounted device 3a from the relay frames stored in receive buffers Rb and Rc to transmit buffer Ta. Similarly, relay device 2 transfers relay frames destined for vehicle-mounted device 3b from the relay frames stored in receive buffers Ra and Rc to transmit buffer Tb. Relay device 2 transfers relay frames destined for vehicle-mounted device 3c from the relay frames stored in receive buffers Ra and Rb to transmit buffer Tc.

[0076] The communication frames stored in the receive buffers Ra, Rb, and Rc are sent to the vehicle-mounted devices 3a, 3b, and 3c, respectively. Therefore, the relay device 2 transfers the communication frames stored in the receive buffers Ra, Rb, and Rc to the transmit buffers Ta, Tb, and Tc, respectively.

[0077] Relay device 2 sends relay frames and communication frames stored in transmit buffer Ta to vehicle-mounted device 3a. Similarly, relay device 2 sends relay frames and communication frames stored in transmit buffer Tb to vehicle-mounted device 3b. Relay device 2 sends relay frames and communication frames stored in transmit buffer Tc to vehicle-mounted device 3c.

[0078] Figure 3 This is an explanatory diagram of the actions performed within the transmit buffer Ta. Transmit buffers Ta, Tb, and Tc are respectively configured with a first queue Q1, a second queue Q2, and a communication queue Qm as storage areas. Onboard devices 3a, 3b, and 3c transmit two types of relay frames. Hereinafter, these two types of relay frames will be referred to as the first relay frame and the second relay frame, respectively.

[0079] Relay device 2 writes a first relay frame, whose target is vehicle-mounted device 3a, into the first queue Q1 in the transmission buffer Ta. Simultaneously, relay device 2 writes a second relay frame, whose target is vehicle-mounted device 3a, into the second queue Q2 in the transmission buffer Tb. Relay device 2 then writes communication frames whose target is vehicle-mounted device 3a into the communication queue Qm.

[0080] The writes performed by relay device 2 in each of the transmit buffers Tb and Tc are the same as those performed in the transmit buffer Ta. Relay device 2 writes the first relay frame, the second relay frame, and the communication frame, respectively, to the first queue Q1, the second queue Q2, and the communication queue Qm of transmit buffer Tb, with the target being the vehicle-mounted device 3b. Relay device 2 writes the first relay frame, the second relay frame, and the communication frame, respectively, to the first queue Q1, the second queue Q2, and the communication queue Qm of transmit buffer Tc, with the target being the vehicle-mounted device 3c.

[0081] If a first relay frame is stored in the first queue Q1 in each of the transmit buffers Ta, Tb, and Tc, the relay device 2 transmits or discards the first relay frame stored in the first queue Q1. After transmitting the first relay frame, the relay device 2 discards the transmitted first relay frame. The discarding of the relay frame is achieved by deleting the relay frame from the device storage unit 22.

[0082] Similarly, when a second relay frame is stored in the second queue Q2 in each of the transmission buffers Ta, Tb, and Tc, the relay device 2 transmits or discards the second relay frame stored in the second queue Q2. After transmitting the second relay frame, the relay device 2 discards the transmitted second relay frame. When a communication frame is stored in the communication queue Qm in each of the transmission buffers Ta, Tb, and Tc, the relay device 2 transmits or discards the communication frame stored in the communication queue Qm. After transmitting the communication frame, the relay device 2 discards the transmitted communication frame. The discarding of a communication frame is achieved by deleting the communication frame from the device storage unit 22.

[0083] Figure 4 This is an explanatory diagram illustrating the relay frame determination method performed by relay device 2. Relay device 2 has a master counter 20 (see reference). Figure 8 The count value is stored in the main counter 20. Figure 4 The display shows the count value of the main counter 20. A certain count is predetermined. The count value is 2 or higher. Every certain period of time, the main counter 20 increments the count value by 1. When the count value is (count value) - 1, the main counter 20 resets the count value to zero after a certain period of time. Figure 4 In the example, the count is 120. One period is represented by (count)·(a certain period). "·" represents the product.

[0084] For the first queue Q1 and the second queue Q2, the open and close periods are set alternately and repeatedly. Figure 4 In the example, for the first queue Q1, the period with count values ​​in the range of 0 to 74 is the open period. The period with count values ​​in the range of 75 to 119 is the closed period. For the second queue Q2, the period with count values ​​in the range of 0 to 74 is the closed period. The period with count values ​​in the range of 75 to 119 is the open period.

[0085] Relay device 2 determines whether a first relay frame is stored in the first queue Q1. If it determines that a first relay frame is stored in the first queue Q1, relay device 2 determines the period to which the relay determination time point belongs from the open period and the close period. Similarly, relay device 2 determines whether a second relay frame is stored in the second queue Q2. If it determines that a second relay frame is stored in the second queue Q2, relay device 2 determines the period to which the relay determination time point belongs from the open period and the close period.

[0086] Figure 5 This is a graph showing the relationship between relay decision time points and actions related to relay frames. For example... Figure 5 As shown, relay device 2 transmits the first relay frame when the period of the first queue Q1 to which the relay determination time point belongs is an open period. The first relay frames stored in transmission buffers Ta, Tb, and Tc are respectively sent to vehicle-mounted devices 3a, 3b, and 3c. When the period to which the relay determination time point belongs is a closed period, relay device 2 discards the first relay frame.

[0087] Similarly, for the second relay frame, if the relay device 2 transmits the second relay frame during the open period of the second queue Q2 to which the relay determination time point belongs, the second relay frame stored in the transmission buffers Ta, Tb, and Tc respectively is transmitted to the vehicle-mounted devices 3a, 3b, and 3c. If the relay device 2 discards the second relay frame if the period to which the relay determination time point belongs is the closed period, the second relay frame is also discarded.

[0088] The opening period of the first queue Q1 and the second queue Q2 is equivalent to the allow period for transmitting relay frames. The closing period of the first queue Q1 and the second queue Q2 is equivalent to the prohibition period for transmitting relay frames.

[0089] exist Figure 4 The diagram illustrates the method for determining the first and second relay frames stored in the transmission buffer Ta. Figure 4 The first layer shows the relay determination time points of the first and second relay frames sent by the vehicle-mounted device 3b to the relay device 2. Figure 4 The second layer shows the relay determination time points for the first and second relay frames sent by the vehicle-mounted device 3c to the relay device 2. Figure 4 The third layer shows the first and second relay frames sent by relay device 2 to vehicle-mounted equipment 3a.

[0090] like Figure 4 As shown, among multiple first relay frames whose transmission source is one of the vehicle-mounted devices 3b and 3c, the first relay frame whose relay determination time point belongs to the open period of the first queue Q1 is transmitted by the relay device 2 to the vehicle-mounted device 3a. Among multiple first relay frames whose transmission source is one of the vehicle-mounted devices 3b and 3c, the first relay frame whose relay determination time point belongs to the closed period of the first queue Q1 is discarded by the relay device 2.

[0091] Similarly, among multiple second relay frames whose transmission source is one of the vehicle-mounted devices 3b and 3c, the second relay frame whose relay determination time point belongs to the open period of the second queue Q2 is transmitted by the relay device 2 to the vehicle-mounted device 3a. Among multiple second relay frames whose transmission source is one of the vehicle-mounted devices 3b and 3c, the second relay frame whose relay determination time point belongs to the closed period of the second queue Q2 is discarded by the relay device 2.

[0092] Relay device 2 transmits and discards relay frames according to the IEEE 802.1Qbv and IEEE 802.1Qci standards as described above. IEEE is a registered trademark and is an abbreviation for the Institute of Electrical and Electronics Engineers.

[0093] Figure 6 This is an explanatory diagram illustrating the communication frame determination method performed by relay device 2. For communication queue Qm, an open period and a close period are alternately and repeatedly set. One cycle includes an open period and a close period. The open period and close period of communication queue Qm correspond to the first period and the second period, respectively. One cycle corresponds to a predetermined period. Relay device 2 determines whether a communication frame is stored in communication queue Qm. If it determines that a communication frame is stored in communication queue Qm, relay device 2 determines the period to which the communication determination time point belongs from the open period and the close period.

[0094] Figure 7 It is a graph showing the relationship between communication decision points and actions related to communication frames. For example... Figure 6As shown, for a communication frame, relay device 2 transmits the communication frame when the communication determination time point belongs to an open period. The communication frames stored in transmission buffers Ta, Tb, and Tc are respectively sent to vehicle-mounted devices 3a, 3b, and 3c. For a communication frame, relay device 2 discards the communication frame when the communication determination time point belongs to a closed period.

[0095] exist Figure 6 The method for determining the communication frames stored in the transmit buffer Ta is shown in the figure. Figure 6 The first layer shows the communication determination time point of the communication frame sent by the vehicle-mounted device 3a to the relay device 2. Figure 6 The second layer shows the communication frames sent by relay device 2 to vehicle-mounted equipment 3a. For example... Figure 6 As shown, communication frames whose communication determination time point belongs to the open period of communication queue Qm are sent by relay device 2 to vehicle-mounted device 3a. Communication frames whose communication determination time point belongs to the closed period of communication queue Qm are discarded by relay device 2.

[0096] Relay device 2 transmits and discards communication frames in accordance with the IEEE 802.1Qbv and IEEE 802.1Qci standards as described above.

[0097] like Figure 6 As shown, each time a cycle is completed, relay device 2 can change the total number of open and closed periods contained in a cycle. Figure 6 In the example, relay device 2 changes the total number of open and closed periods in one cycle from 2 to 4. Onboard device 3a repeatedly indicates the transmission of communication frames at times when the count value is zero.

[0098] For each of the K cycles, relay device 2 determines the period to which the communication determination time point of the communication frame belongs. K is an integer greater than or equal to 2. Based on the K determination results related to the period, vehicle-mounted device 3a determines the range to which the communication determination time point belongs within a cycle. Based on the determined range, vehicle-mounted device 3a determines the overall period from the indication of transmission of the communication frame in vehicle-mounted device 3a up to the communication determination time point. Based on the determined overall period, vehicle-mounted device 3a indicates the transmission of the first relay frame and the second relay frame in a manner that makes the relay determination time point belong to the open period.

[0099] Similarly, on-board devices 3b and 3c repeatedly indicate the transmission of communication frames at time points when the count value is zero. On-board devices 3b and 3c determine their respective ranges in the same way as on-board device 3a. On-board devices 3b and 3c determine their overall durations in the same way as on-board device 3a. On-board devices 3b and 3c indicate the transmission of the first and second relay frames in the same way as on-board device 3a.

[0100] <Structure of Relay Device 2>

[0101] Figure 8 This is a block diagram showing the main structural components of relay device 2. As described above, relay device 2 includes a master counter 20 and a device storage unit 22. Relay device 2 also includes three device communication ICs 21a, 21b, and 21c, and a device control unit 23. IC is an abbreviation for Integrated Circuit. The master counter 20, device communication ICs 21a, 21b, and 21c, device storage unit 22, and device control unit 23 are connected to the device bus 24. Device communication ICs 21a, 21b, and 21c are connected to connectors 2a, 2b, and 2c, respectively. As described above, vehicle-mounted devices 3a, 3b, and 3c are connected to connectors 2a, 2b, and 2c, respectively.

[0102] The communication ICs 21a, 21b, and 21c receive relay frames, communication frames, request data, and start data from the vehicle-mounted devices 3a, 3b, and 3c, respectively. The communication ICs 21a, 21b, and 21c function as receiving units and relay receiving units, respectively. Following the instructions of the control unit 23, the communication ICs 21a, 21b, and 21c transmit relay frames, communication frames, response data, count data, mode data, and target data to the vehicle-mounted devices 3a, 3b, and 3c.

[0103] The request data is the data that requests the transmission of response data. The start data indicates the beginning of communication frame transmission. Response data is sent upon receiving the request data. The count data represents the count value of the master counter 20. The mode data represents the configuration for the on and off periods for K cycles. The target data represents the target time point. The target time point is the time at which a determination should be made as to whether a relay frame is stored.

[0104] Figure 9 This is a diagram illustrating the content of the pattern data. In Figure 9 The example shown is a count of 120 and K = 3. In the pattern data, the configuration of the on and off periods for each of the first, second, and third cycles is represented by the count value of the master counter 20. For example, the on period of the first cycle is a period with count values ​​ranging from 0 to 59. The off period of the first cycle is a period with count values ​​ranging from 60 to 119. Figure 9 In the example, for each of the K cycles, the number of open periods is the same as the number of closed periods.

[0105] The total number of open and closed periods in the i-th cycle is 2^i. Here, i is any natural number below K, and can also be any one of 1, 2, ..., K. Figure 9 In the example, the multiple periods contained in each period are of the same length. Furthermore, the length of each of the multiple periods contained in each period may also differ from the length of at least one of the other periods.

[0106] According to the pattern data, relay device 2 changes the total number and boundary positions of the open and close periods of communication queue Qm from the first cycle to the Kth cycle. The boundary of the change is the boundary between the open and close periods. Each time a cycle passes, relay device 2 changes the total number of open and close periods of communication queue Qm in the next cycle. Relay device 2 changes the total number of open and close periods in each cycle in a way that the total number in each of the K consecutive cycles is different.

[0107] Figure 10 This is a graph representing the content of the target data. As mentioned above, the target data represents the target time point of the relay frame. The target time point is represented by the count value of the master counter 20. Figure 10 The target data used by the vehicle-mounted device 3a is shown. The vehicle-mounted device 3a sends the first relay frame and the second relay frame to the device communication IC 21a in a manner that makes the relay determination time point the target time point.

[0108] exist Figure 10 In the example, vehicle-mounted device 3a sends a first relay frame to vehicle-mounted device 3b at the time when the main counter 20 reaches a count of 0, making it the relay determination time point. Vehicle-mounted device 3a also sends a first relay frame to vehicle-mounted device 3c at the time when the main counter 20 reaches a count of 20, making it the relay determination time point. Similarly, vehicle-mounted device 3a sends a second relay frame to vehicle-mounted device 3b at the time when the main counter 20 reaches a count of 60, making it the relay determination time point. Finally, vehicle-mounted device 3a sends a second relay frame to vehicle-mounted device 3c at the time when the main counter 20 reaches a count of 100, making it the relay determination time point.

[0109] The target data used by vehicle-mounted devices 3b and 3c contains the same content as the target data used by vehicle-mounted device 3a. The target data used by vehicle-mounted device 3b shows the content of a relay frame whose transmission target is either vehicle-mounted device 3a or 3c. The target data used by vehicle-mounted device 3c shows the content of a relay frame whose transmission target is either vehicle-mounted device 3a or 3b. Preferably, the target time points of multiple first relay frames with the same transmission target but different transmission sources are different. Similarly, it is preferable that the target time points of multiple second relay frames with the same transmission target but different transmission sources are different.

[0110] exist Figure 8The device storage unit 22 stores pattern data and three target data. The device control unit 23 has a processing element, such as a CPU (Central Processing Unit), for performing processing. The device control unit 23 functions as a processing unit and a relay processing unit. The device storage unit 22 also stores a computer program Pr. The computer program Pr is a program product. The processing element (computer) of the device control unit 23 executes the computer program Pr to perform three data transmission processes, three period change processes, data movement processes, communication frame relay processes for each of the transmission buffers Ta, Tb, and Tc, and the first and second relay processes for transmission buffers Ta, Tb, and Tc.

[0111] The three data transmission processes are for sending response data, count data, mode data, and target data to onboard devices 3a, 3b, and 3c, respectively. The period change processing, based on the mode data, changes the total number and boundary positions during the open and closed periods of communication queue Qm from the first cycle to the Kth cycle. These three period change processes correspond to communication queues Qm in transmit buffers Ta, Tb, and Tc, respectively. The data movement processing moves relay frames or communication frames from one of the receive buffers Ra, Rb, and Rc to at least one of the transmit buffers Ta, Tb, and Tc. The communication frame relay processing relays communication frames. The first relay processing relays the first relay frame. The second relay processing relays the second relay frame.

[0112] Furthermore, the computer program Pr can also be provided to the relay device 2 using a non-transitory storage medium Ar in a readable manner. The storage medium Ar is, for example, a portable memory. Examples of portable memory include CD-ROMs, USB (Universal Serial Bus) memory, SD cards, micro SD cards, or compact flash memory (registered trademark). When the storage medium Ar is a portable memory, the processing element of the device control unit 23 can also read the computer program Pr from the storage medium Ar using a reading device (not shown). The read computer program Pr is written to the device storage unit 22. Furthermore, the computer program Pr can also be provided to the relay device 2 by communicating with an external device via a communication unit (not shown) of the relay device 2. In this case, the processing element of the device control unit 23 obtains the computer program Pr via the communication unit. The obtained computer program Pr is written to the device storage unit 22.

[0113] Furthermore, the number of processing elements in the device control unit 23 is not limited to one, but may be two or more. When the device control unit 23 has multiple processing elements, the multiple processing elements can also collaboratively perform the aforementioned processes such as three data transmission processes and three period change processes.

[0114] The device storage unit 22 is composed of, for example, non-volatile memory and volatile memory. In this case, the non-volatile memory of the device storage unit 22 stores, for example, computer program Pr, pattern data, and target data. In the storage area of ​​the volatile memory of the device storage unit 22, for example, three receive buffers Ra, Rb, and Rc and three transmit buffers Ta, Tb, and Tc are provided.

[0115] <Structure of vehicle-mounted equipment 3a, 3b, and 3c>

[0116] Figure 11 This is a block diagram showing the main structural components of the vehicle-mounted device 3a. The vehicle-mounted device 3a includes a counter 30, a device communication IC 31, a device storage unit 32, and a device control unit 33. These are connected to a device bus 34. The device communication IC 31 is also connected to a device connector B. The device connector B of the vehicle-mounted device 3a is detachably connected to the connection connector 2a.

[0117] The slave counter 30 stores a count value. Similar to the master counter 20, the slave counter 30 increments its count by 1 after a certain period. The certain period and count of the slave counter 30 are the same as those of the master counter 20. When the count value is (count count) - 1, the slave counter 30 resets its count to zero after a certain period. The device control unit 33 synchronizes the count value of the slave counter 30 with the count value of the master counter 20.

[0118] The device communication IC 31 receives relay frames, communication frames, response data, count data, mode data, and target data from the device communication IC 21a of the relay device 2. Following the instructions of the device control unit 33, the device communication IC 31 transmits relay frames, communication frames, request data, and start data.

[0119] The device storage unit 32 stores a computer program Pe. The computer program Pe is a program product. The device control unit 33 has a processing element, such as a CPU, that performs processing. The device control unit 33 functions as a communication processing unit. The processing element (computer) of the device control unit 33 performs adjustment processing, period determination processing, write processing, and relay frame transmission processing, etc., by executing the computer program Pe.

[0120] During the adjustment process, the device control unit 33 adjusts the count value from the counter 30. During the adjustment process, the device control unit 33 also writes mode data and target data to the device storage unit 32. The period determination process determines the overall period. The write process writes the relay frame to the device storage unit 32. The relay frame transmission process transmits the relay frame to the relay device 2.

[0121] Furthermore, the computer program Pe can also be provided to the vehicle-mounted device 3a using a non-temporary storage medium Ae in which the computer program Pe is stored in a readable manner. The storage medium Ae is, for example, a portable memory. When the storage medium Ae is a portable memory, the processing element of the device control unit 33 can also read the computer program Pe from the storage medium Ae using a reading device (not shown). The read computer program Pe is written to the device storage unit 32. Furthermore, the computer program Pe can also be provided to the vehicle-mounted device 3a by communicating with an external device via a communication unit (not shown) of the vehicle-mounted device 3a. In this case, the processing element of the device control unit 33 obtains the computer program Pe through the communication unit. The obtained computer program Pe is written to the device storage unit 32.

[0122] Furthermore, the number of processing elements in the device control unit 33 is not limited to one, but may be two or more. When the device control unit 33 has multiple processing elements, the multiple processing elements can also collaboratively perform adjustment processing, period determination processing, write processing, and relay frame transmission processing, etc.

[0123] The device storage unit 32 may be composed of, for example, non-volatile memory and volatile memory. In this case, the non-volatile memory of the device storage unit 32 stores, for example, computer program Pe and target data.

[0124] Vehicle-mounted devices 3b and 3c are configured similarly to vehicle-mounted device 3a. Connector 2a corresponds to connectors 2b and 2c. Device communication IC 21a corresponds to device communication ICs 21b and 21c.

[0125] <Initial settings performed on relay device 2>

[0126] Figure 12 and Figure 13 This is a flowchart illustrating the initial setup steps performed by the relay device 2 and the vehicle-mounted device 3a. During the initial setup, the device control unit 23 of the relay device 2 performs data transmission processing. The device control unit 33 of the vehicle-mounted device 3a performs adjustment processing. The device control unit 23 of the relay device 2 performs data transmission processing when the vehicle-mounted device 3a is disconnected from the connector 2a. The device control unit 33 of the vehicle-mounted device 3a performs adjustment processing when the vehicle-mounted device 3a is connected to the connector 2a.

[0127] During data transmission processing, the device control unit 23 determines whether the vehicle-mounted device 3a is connected to the connector 2a (step S1). If the device control unit 23 determines that the vehicle-mounted device 3a is not connected to the connector 2a (S1: No), it executes step S1 again and waits until the vehicle-mounted device 3a is connected to the connector 2a. If the device control unit 23 determines that the vehicle-mounted device 3a is connected to the connector 2a (S1: Yes), it instructs the device communication IC 21a to send the count data representing the count value of the master counter 20 to the device communication IC 31 of the vehicle-mounted device 3a (step S2).

[0128] During the adjustment process, the device control unit 33 of the vehicle-mounted device 3a determines whether the device communication IC 31 has received the counting data (step S11). If the device control unit 33 determines that the device communication IC 31 has not received the counting data (S11: No), it executes step S11 again and waits until the device communication IC 31 receives the counting data. If the device control unit 33 determines that the device communication IC 31 has received the counting data (S11: Yes), it adjusts the count value from the counter 30 to the count value represented by the counting data received by the device communication IC 31 (step S12).

[0129] Next, the device control unit 33 instructs the device communication IC 31 to send the request data to the device communication IC 21a of the relay device 2 (step S13). The request data includes device transmission count information indicating the count value of the slave counter 30 at the time when the request data was sent. Hereinafter, the count value of the slave counter 30 at the time when the request data was sent will be recorded as the device transmission count value.

[0130] After executing step S2, the device control unit 23 of relay device 2 determines whether the device communication IC 21a has received the requested data (step S3). If the device control unit 23 determines that the device communication IC 21a has not received the requested data (S3: No), it executes step S3 again and waits until the device communication IC 21a receives the requested data. If the device control unit 23 determines that the device communication IC 21a has received the requested data (S3: Yes), it instructs the device communication IC 21a to send response data to the device communication IC 31 of the vehicle-mounted device 3a (step S4).

[0131] The response data includes device transmission count information, device reception count information, and device transmission count information contained in the request data. The device reception count information represents the count value of the main counter 20 at the time when the device communication IC 21a receives the request data. The device transmission count information represents the count value of the main counter 20 at the time when the device communication IC 21a sends the response data. Hereinafter, the count value of the main counter 20 at the time when the device communication IC 21a receives the request data will be recorded as the device reception count value. The count value of the main counter 20 at the time when the device communication IC 21a sends the response data will be recorded as the device transmission count value.

[0132] After executing step S13, the device control unit 33 of the vehicle-mounted device 3a determines whether the device communication IC 31 has received response data from the device communication IC 21a of the relay device 2 (step S14). If the device control unit 33 determines that the device communication IC 31 has not received response data (S14: No), it executes step S14 again and waits until the device communication IC 31 receives response data.

[0133] Hereinafter, the count value of the slave counter 30 at the time when the device communication IC 31 receives the response data will be recorded as the device receive count value. As mentioned above, the response data includes device transmit count information, device receive count information, and device transmit count information.

[0134] The device transmit count value, device receive count value, device transmit count value, and device receive count value are represented by Het, Hrr, Hrt, and Her, respectively. The propagation time of the request data and response data is considered to be the same. In this case, the difference Hd between the count values ​​of the master counter 20 and the slave counter 30 is represented by the following equation (1).

[0135] Hd=((Hrr-Het)-(Her-Hrt)) / 2...(1)

[0136] When the device control unit 33 determines that the device communication IC 31 has received response data (S14: Yes), it performs a fine adjustment of the count value of the slave counter 30 based on the difference Hd (step S15). As described above, when the device communication IC 31 of the vehicle-mounted device 3a receives count data from the device communication IC 21a of the relay device 2, the device control unit 33 adjusts the count value of the slave counter 30 to the count value represented by the count data received by the device communication IC 31. Therefore, the count value of the slave counter 30 is less than the actual count value of the master counter 20.

[0137] In step S15, the device control unit 33 increments the count value of the slave counter 30 by the absolute value of the difference Hd. As a result, the count value of the slave counter 30 is substantially the same as the count value of the master counter 20.

[0138] Furthermore, regarding equation (1), when Hrr is smaller than Het, the count value is used to reach the value required for Hrr from Het, as (Hrr-Het). When Hrt is smaller than Her, the count value is used to reach the value required for Her from Hrt, as (Her-Hrt).

[0139] Furthermore, the method for calculating the difference Hd is not limited to the method using equation (1).

[0140] After executing step S4, the device control unit 23 of relay device 2 instructs device communication IC 21a to send mode data to device communication IC 31 of vehicle-mounted device 3a (step S5). After executing step S15, the device control unit 33 of vehicle-mounted device 3a determines whether device communication IC 31 has received mode data from device communication IC 21a (step S16). If the device control unit 33 determines that device communication IC 31 has not received mode data (S16: No), it executes step S16 again and waits until device communication IC 31 receives mode data.

[0141] When the device control unit 33 determines that the device communication IC 31 has received mode data (S16: Yes), it writes the mode data received by the device communication IC 31 into the device storage unit 32 (step S17).

[0142] After executing step S5, the device control unit 23 of relay device 2 instructs device communication IC 21a to send target data for vehicle-mounted device 3a to device communication IC 31 of vehicle-mounted device 3a (step S6). After executing step S6, device control unit 23 ends the data transmission process. If vehicle-mounted device 3a is disconnected from connector 2a, device control unit 23 executes the data transmission process again.

[0143] After executing step S17, the device control unit 33 of the vehicle-mounted device 3a determines whether the device communication IC 31 has received the target data of the vehicle-mounted device 3a from the device communication IC 21a (step S18). If the device control unit 33 determines that the device communication IC 31 has not received the target data (S18: No), it executes step S18 again and waits until the device communication IC 31 receives the target data.

[0144] When the device control unit 33 determines that the device communication IC 31 has received target data for the vehicle-mounted device 3a (S18: Yes), it writes the target data for the vehicle-mounted device 3a received by the device communication IC 31 into the device storage unit 32 (step S19). After executing step S19, the device control unit 33 ends the adjustment process. If the vehicle-mounted device 3a is disconnected from the connector 2a and then reconnected to the connector 2a, the device control unit 33 executes the adjustment process again.

[0145] As described above, when the device control unit 23 and the equipment control unit 33 respectively perform data transmission processing and adjustment processing, the count values ​​of the master counter 20 and the slave counter 30 are substantially the same. Furthermore, the device storage unit 32 of the vehicle-mounted equipment 3a stores mode data and target data used by the vehicle-mounted equipment 3a.

[0146] Furthermore, if the count and time period of the slave counter 30 are inconsistent with the count and time period of the master counter 20, the device communication IC 21a of the relay device 2 sends the count value, count, and time period of the master counter 20 to the device communication IC 31 of the vehicle-mounted device 3a in step S2. Upon receiving the count data, the device control unit 33 adjusts the count value, count, and time period of the slave counter 30 to the count value, count, and time period represented by the count data.

[0147] The initial settings of relay device 2 with vehicle-mounted devices 3b and 3c are the same as the initial settings of relay device 2 with vehicle-mounted device 3a. Connector 2a corresponds to connectors 2b and 2c. Device communication IC 21a corresponds to device communication ICs 21b and 21c.

[0148] <An overview of the methods for determining the overall period>

[0149] Figure 14 This is a timing diagram outlining the method for determining the overall duration of the vehicle-mounted device 3a. After the count value of the master counter 20 is synchronized with the count value of the slave counter 30, the vehicle-mounted device 3a determines its overall duration. The vehicle-mounted device 3a first sends start data to the relay device 2. Upon receiving the start data, the relay device 2 waits until the count value of the master counter 20 becomes zero.

[0150] When the count value becomes zero, relay device 2 begins to change according to the period of the pattern data. As described above, relay device 2 changes the total number and boundary positions, etc., for the open and closed periods of communication queue Qm according to the pattern data, from the first period to the Kth period. The boundary of the change is the boundary between the open and closed periods. Relay device 2 repeats the change according to the period of the pattern data N times. Here, N is an integer greater than 2.

[0151] After sending start data, vehicle-mounted device 3a waits until the count value of counter 30 reaches zero. When the count value reaches zero, vehicle-mounted device 3a sends a communication frame to relay device 2. Upon receiving the communication frame, relay device 2 writes the received communication frame into receive buffer Ra. Then, relay device 2 transfers the communication frame stored in receive buffer Ra to transmit buffer Ta. Next, relay device 2 determines whether a communication frame is stored in transmit buffer Ta.

[0152] When relay device 2 determines that a communication frame is stored in the transmit buffer Ta, it determines the period to which the determined communication determination time point belongs within the open or closed period of the communication queue Qm. If the determined period is an open period, relay device 2 transmits the communication frame to the vehicle-mounted device 3a. If the determined period is a closed period, relay device 2 discards the communication frame. Therefore, for vehicle-mounted device 3a, receiving a communication frame means that the period determined by relay device 2 is an open period. For vehicle-mounted device 3a, not receiving a communication frame means that the period determined by relay device 2 is a closed period. The reception result is equivalent to the determination result related to the period.

[0153] Whenever the count value reaches zero, the vehicle-mounted device 3a sends a communication frame to the relay device 2. The vehicle-mounted device 3a sends (K·N) communication frames to the relay device 2. Based on the (K·N) received results, the N ranges to which the communication determination time point belongs are determined.

[0154] Figure 15 This is an illustration of the method for determining the scope. In Figure 15 The text shows the use of... Figure 9 The example shown is pattern data. In Figure 9 In the example, K is 3. The on-board device 3a determines the range based on K received results. Figure 15 The diagram illustrates an example where relay device 2 receives K communication determination time points of 67 from vehicle-mounted device 3a. Vehicle-mounted device 3a does not recognize the case where communication determination time point 67 is received. Therefore, vehicle-mounted device 3a also fails to identify the range to which the communication determination time point belongs. Vehicle-mounted device 3a receives mode data from relay device 2.

[0155] When the communication determination time point is 67, relay device 2 discards the communication frames sent from vehicle-mounted device 3a in the first cycle. Relay device 2 then sends the communication frames sent from vehicle-mounted device 3a in the second cycle back to vehicle-mounted device 3a. Relay device 2 then sends the communication frames sent from vehicle-mounted device 3a in the third cycle back to vehicle-mounted device 3a. Based on the three reception results, vehicle-mounted device 3a identifies the three periods determined by relay device 2 in the first, second, and third cycles as the off period, the on period, and the on period, respectively.

[0156] When the range of the three periods is the closing period, the opening period, and the opening period, respectively, and the range is the one to which it belongs, Figure 15 In this example, the range is between 60 and 74. Thus, the vehicle-mounted device 3a determines the range based on K received results.

[0157] Furthermore, the opening and closing periods of the pattern data are configured such that the number of the three periods corresponding to the three cycles is one for each of the ranges of closing, opening, and opening periods. Specifically, in the i-th cycle of the pattern data, the opening and closing periods are configured such that the number of each of the opening and closing periods existing in the common range of the first to (i-1)-th cycles is less than one.

[0158] exist Figure 15 In the first cycle, the number of common ranges is 2. The first common range is the open period of the first cycle. The second common range is the closed period of the first cycle. Regarding the second cycle, the number of open periods and closed periods belonging to each common range is 1 each.

[0159] The number of common ranges for the first and second cycles is 4. The first common range consists of two periods corresponding to the first and second cycles, where the period is open and the period is closed, respectively. The third common range consists of two periods corresponding to the first and second cycles, where the period is closed and the period is open, respectively. The fourth common range consists of two periods corresponding to the first and second cycles, where the period is closed and the period is closed, respectively. Regarding the third cycle, the number of open and closed periods within each common range of the first and second cycles is 1. Within the common ranges, only open or closed periods can also be configured.

[0160] like Figure 14As shown, after determining N belonging ranges, the vehicle-mounted device 3a determines the overall duration based on the determined N belonging ranges. The overall duration is represented by the width of the count value from the transmission indication value indicating the transmission of the communication frame to the communication determination time point. The transmission indication value is a count value. As mentioned above, the count value increments by 1 every certain period. Therefore, the overall duration is the product of the count value width and the certain period. As mentioned above, the vehicle-mounted device 3a indicates the transmission of the communication frame when the count value is zero. Therefore, the count value at the communication determination time point represents the overall duration.

[0161] In order to determine the overall duration of the vehicle-mounted device 3a, it first determines the calculated value used to calculate the overall duration. If the N determined belonging ranges are the same, the vehicle-mounted device 3a determines the calculated value as the central value of the determined belonging ranges. The vehicle-mounted device 3a determines the overall duration as the product of the value obtained by subtracting the transmission indication value (=0) of the communication frame from the determined calculated value and a certain duration. The determined overall duration is represented by the value obtained by subtracting the transmission indication value from the calculated value. The N belonging ranges determined by the vehicle-mounted device 3a may include two ranges. That is, there is a possibility that ranges E1 and E2 exist as belonging ranges.

[0162] Figure 16 This diagram illustrates the method for determining the overall period when there are two ranges, E1 and E2, as the scope to which the device belongs. When the vehicle-mounted device 3a transmits multiple communication frames, the communication determination time points for these frames may be inconsistent. That is, the communication determination time points may change.

[0163] exist Figure 16 In the example, the communication determination time point varies around 75. Range E1 is the range from 60 to 74. Range E2 is the range from 75 to 89. When there are two ranges E1 and E2 as the belonging ranges, the vehicle-mounted device 3a determines the calculated value of the overall period as the value of the majority range of ranges E1 and E2. The more numerous the minority ranges of ranges E1 and E2, the closer the vehicle-mounted device 3a determines the calculated value of the overall period as the value of the minority range.

[0164] For example, if the number of values ​​in range E2 is greater than the number in range E1, the on-board device 3a will determine the calculated value as the value within range E2. The more values ​​in range E1 there are, the closer the calculated value within range E2 will be to the value within range E1. Thus, the overall period considering the variation in the communication decision time point is determined.

[0165] Furthermore, the method for determining the overall period is not limited to the methods described above. The overall period can be determined simply by basing it on the identified N constituent ranges; there is no problem with that.

[0166] The method for determining the overall duration of vehicle-mounted devices 3b and 3c is the same as the method for determining the overall duration of vehicle-mounted device 3a.

[0167] The following describes the specific processing performed on the device control unit 23 of relay device 2 and the vehicle-mounted equipment 3a, 3b, and 3c regarding the method for determining the overall duration.

[0168] <Changes in the period of the pattern data>

[0169] Figure 17 This is a flowchart illustrating the steps of the period change processing corresponding to the communication queue Qm of the transmission buffer Ta. The period change processing is executed by the device control unit 23 of the relay device 2 after initial settings. The value of variable U is stored in the device storage unit 22 of the relay device 2. The device control unit 23 changes the value of variable U. In the period change processing, the device control unit 23 first determines whether the device communication IC 21a has received start data from the vehicle-mounted device 3a (step S21). If the device control unit 23 determines that the device communication IC 21a has not received start data (S21: No), it executes step S21 again and waits until the device communication IC 21a receives start data.

[0170] If the device control unit 23 determines that the device communication IC 21a has received start data (S21: Yes), it sets the value of variable U to zero (step S22) and determines whether the count value of the main counter 20 is zero (step S23). If the device control unit 23 determines that the count value is not zero (S23: No), it executes step S23 again and waits until the count value becomes zero.

[0171] When the device control unit 23 determines that the count value is zero (S23: Yes), it changes the period according to the mode data (step S24). As described above, the device control unit 23 changes the total number of open and closed periods in the next cycle according to the mode data, each time one cycle has elapsed. The device control unit 23 changes the total number of open and closed periods in each cycle in such a way that the total number of each of the K consecutive cycles is different. Then, the device control unit 23 increments the value of variable U by 1 (step S25).

[0172] After executing step S25, the device control unit 23 determines whether the value of variable U is N (step S26). If the device control unit 23 determines that the value of variable U is not N (S26: No), it executes step S23 again and performs the period change according to the pattern data. If the device control unit 23 determines that the value of variable U is N (S26: Yes), it ends the period change process. After ending the period change process, the device control unit 23 performs the period change process again.

[0173] As described above, during the period change processing, the device control unit 23 repeats the period change according to the mode data N times.

[0174] The period change processing corresponding to the communication queue Qm of the transmit buffers Tb and Tc is the same as the period change processing corresponding to the communication queue Qm of the transmit buffer Ta. Device communication IC21a corresponds to device communication ICs 21b and 21c. Onboard device 3a corresponds to onboard devices 3b and 3c.

[0175] <Communication frames and relay frame movement performed by relay device 2>

[0176] As described above, the device control unit 23 of the relay device 2 performs data movement processing. During this processing, the device control unit 23 writes the communication frames received by the device communication ICs 21a, 21b, and 21c into the receive buffers Ra, Rb, and Rc of the device storage unit 22, respectively. The device control unit 23 then transfers the communication frames stored in the receive buffers Ra, Rb, and Rc to the communication queue Qm of the transmit buffers Ta, Tb, and Tc, respectively. The device storage unit 22 functions as a relay storage unit.

[0177] The device control unit 23 writes the relay frames received by the device communication ICs 21a, 21b, and 21c into the receive buffers Ra, Rb, and Rc, respectively. Within the relay frames stored in the receive buffers Rb and Rc, the device control unit 23 transfers the relay frame destined for the vehicle-mounted device 3a to the transmit buffer Ta. Here, the device control unit 23 transfers the first relay frame to the first queue Q1 of the transmit buffer Ta. The device control unit 23 then transfers the second relay frame to the second queue Q2 of the transmit buffer Ta.

[0178] Similarly, the device control unit 23 transfers relay frames destined for vehicle-mounted device 3b from the relay frames stored in the receive buffers Ra and Rc to the transmit buffer Tb. Here, the device control unit 23 transfers the first relay frame to the first queue Q1 of the transmit buffer Tb. The device control unit 23 then transfers the second relay frame to the second queue Q2 of the transmit buffer Tb. Similarly, the device control unit 23 transfers relay frames destined for vehicle-mounted device 3c from the relay frames stored in the receive buffers Ra and Rb to the transmit buffer Tc. Here, the device control unit 23 transfers the first relay frame to the first queue Q1 of the transmit buffer Tc. The device control unit 23 then transfers the second relay frame to the second queue Q2 of the transmit buffer Tc.

[0179] <Relay of communication frames performed by relay device 2>

[0180] Figure 18This is a flowchart illustrating the steps of communication frame relay processing for the transmit buffer Ta. In the communication frame relay processing of the transmit buffer Ta, the device control unit 23 of the relay device 2 determines whether a communication frame is stored in the communication queue Qm of the transmit buffer Ta (step S31). If the device control unit 23 determines that no communication frame is stored in the communication queue Qm (S31: No), it executes step S31 again, waiting until a communication frame is written into the communication queue Qm.

[0181] When the device control unit 23 determines that a communication frame is stored in the communication queue Qm (S31: Yes), it reads the count value of the main counter 20 (step S32). The count value read in step S32 corresponds to the communication determination time point at which it was determined that a communication frame is stored in the communication queue Qm. Next, the device control unit 23 determines the period to which the count value read in step S32 belongs during the open and closed periods of the communication queue Qm (step S33).

[0182] Next, the device control unit 23 determines whether the period determined in step S33 is an open period (step S34). If the determined period is not an open period, it means that the determined period is a closed period. If the device control unit 23 determines that the determined period is an open period (S34: Yes), it instructs the device communication IC 21a to send a communication frame stored in the communication queue Qm (step S35). As a result, the device communication IC 21a sends the communication frame to the device communication IC 31 of the vehicle-mounted device 3a. The sent communication frame is discarded.

[0183] If the device control unit 23 determines that the determined period is not an open period (S34: No), it discards the communication frame stored in the communication queue Qm (step S36). After executing one of steps S35 and S36, the device control unit 23 ends the communication frame relay processing of the transmission buffer Ta. Then, the device control unit 23 executes the communication frame relay processing of the transmission buffer Ta again.

[0184] As described above, in the communication frame relay processing, the device control unit 23 instructs the device communication IC 21a to send communication frames whose communication determination time point belongs to the open period to the vehicle-mounted device 3a.

[0185] The communication frame relay processing for transmit buffers Tb and Tc is the same as that for transmit buffer Ta. Device communication IC21a corresponds to device communication ICs 21b and 21c. Vehicle-mounted device 3a corresponds to vehicle-mounted devices 3b and 3c.

[0186] <Decisions during the overall period>

[0187] Figure 19This is a flowchart illustrating the steps of the period determination process for the vehicle-mounted device 3a. The period change process for the vehicle-mounted device 3a is executed by the device control unit 33 after initial settings are performed. The values ​​of variables X and Y are stored in the device storage unit 32 of the vehicle-mounted device 3a. The device control unit 33 changes the values ​​of variables X and Y respectively.

[0188] During the decision-making process, the device control unit 33 of the vehicle-mounted device 3a first sets the values ​​of variables X and Y to zero (step S41). Next, the device control unit 33 instructs the device communication IC 31 to begin sending data to the device communication IC 21a of the relay device 2 (step S42). After executing step S42, the device control unit 33 determines whether the count value of the counter 30 is zero (step S43). Here, zero is a predetermined transmission indication value for communication frames. If the device control unit 33 determines that the count value is not zero (the transmission indication value for communication frames) (S43: No), it executes step S43 again and waits until the count value becomes zero.

[0189] When the device control unit 33 determines that the count value is zero (communication frame transmission indication value) (S43: Yes), it instructs the device communication IC 31 to send a communication frame to the device communication IC 21a of the relay device 2 (step S44). Here, the target of the communication frame transmission is the vehicle-mounted device 3a. Upon execution of step S44, the device communication IC 31 sends the communication frame to the device communication IC 21a of the relay device 2. As described above, the device communication IC 21a of the relay device 2 sends the communication frame to the device communication IC 31 when the communication determination time point is during the open period. When the device communication IC 21a of the relay device 2 is during the closed period, it discards the communication frame.

[0190] After executing step S44, the device control unit 33 writes reception result data, representing the reception result of the device communication IC 31 related to the communication frame, into the device storage unit 32 (step S45). Next, the device control unit 33 increments the value of variable X by 1 (step S46). After executing step S46, the device control unit 33 determines whether the value of variable X is K (step S47). If the device control unit 33 determines that the value of variable X is not K (S47: No), it executes step S43 again. When the count value becomes zero, that is, when the next cycle arrives, the device control unit 33 instructs the device communication IC 21a to send a communication frame. As described above, the device control unit 33 instructs the device communication IC 21a to send a communication frame every time a cycle elapses. Every time a cycle elapses, the device communication IC 21a receives a communication frame from the device communication IC 31 of the vehicle-mounted device 3a.

[0191] If the equipment control unit 33 determines that the value of variable X is K (S47: Yes), then... Figure 15 As explained, based on K received results, the range to which the communication determination time point belongs within a cycle is determined (step S48). Next, the device control unit 33 sets the value of variable X to zero (step S49) and increments the value of variable Y by 1 (step S50). After executing step S50, the device control unit 33 determines whether the value of variable Y is N (step S51).

[0192] If the device control unit 33 determines that the value of variable Y is not N (S51: No), it executes step S43 again, instructing the transmission of K communication frames. As described above, the device control unit 33 determines the range to which N belongs. If the device control unit 33 determines that the value of variable Y is N (S51: Yes), it determines the overall duration of the vehicle-mounted device 3a as described above (step S52). Next, the device control unit 33 writes the overall duration data representing the overall duration determined in step S52 into the device storage unit 32 (step S53). After executing step S53, the device control unit 33 ends the duration determination process.

[0193] As described above, the device control unit 33 determines the range to which the communication determination time point belongs based on K received results. Based on the determined N ranges, the device control unit 33 determines the overall period that takes into account the variation of the communication determination time point.

[0194] The timing determination processing of vehicle-mounted devices 3b and 3c is the same as that of vehicle-mounted device 3a. Device communication IC21a corresponds to device communication ICs 21b and 21c.

[0195] <Relay of relay frames performed by relay device 2>

[0196] The device control unit 23 of relay device 2 performs the first relay processing and the second relay processing of transmission buffer Ta in the same manner as the communication frame relay processing of transmission buffer Ta. In the description of the communication frame relay processing of transmission buffer Ta, the communication frame, communication determination time point, and communication queue Qm are replaced with the first relay frame, relay determination time point, and first queue Q1, respectively. This allows for the description of the first relay processing of transmission buffer Ta. In the description of the communication frame relay processing of transmission buffer Ta, the communication frame, communication determination time point, and communication queue Qm are replaced with the second relay frame, relay determination time point, and second queue Q2, respectively. This allows for the description of the second relay processing of transmission buffer Ta.

[0197] The device control unit 23 of relay device 2 executes the first relay processing for each of the transmit buffers Tb and Tc in the same way as the first relay processing for the transmit buffer Ta. The device control unit 23 of relay device 2 executes the second relay processing for each of the transmit buffers Tb and Tc in the same way as the second relay processing for the transmit buffer Ta. The transmit buffer Ta corresponds to the transmit buffers Tb and Tc.

[0198] <Data frame writing performed by vehicle-mounted devices 3a, 3b, and 3c respectively>

[0199] As described above, the device control units 33 of each of the vehicle-mounted devices 3a, 3b, and 3c perform write processing. When each of the vehicle-mounted devices 3a, 3b, and 3c has a sensor, upon receiving sensor data from the sensor, the device control unit 33 generates a relay frame containing the input sensor data during the write processing. When each of the vehicle-mounted devices 3a, 3b, and 3c has a receiving unit for receiving instructions, upon receiving an instruction from the receiving unit, the device control unit 33 generates a relay frame containing instruction data indicating the received instruction during the write processing. The device control unit 33 writes the generated relay frame to the device storage unit 32. The relay frame generated by the device control unit 33 is either a first relay frame or a second relay frame.

[0200] <Transmission of relay frames by vehicle-mounted equipment 3a, 3b, and 3c>

[0201] Figure 20 This is a flowchart illustrating the relay frame transmission process of the vehicle-mounted device 3a. After performing the period determination process, if the device control unit 33 of the vehicle-mounted device 3a writes a relay frame into the device storage unit 32, the device control unit 33 performs the relay frame transmission process. The device storage unit 32 stores overall period data representing the overall period determined in the period determination process.

[0202] In the relay frame transmission process, the device control unit 33 determines the relay frame transmission indication value based on the target time point represented by the target data and the overall period represented by the overall period data (step S61). The relay frame transmission indication value is the count value (time point) of the slave counter 30 that the device control unit 33 instructs the transmission of the relay frame. The relay frame transmission indication value corresponds to the transmission indication time point.

[0203] Assume the relay frame stored in device storage unit 32 is a second relay frame whose target is vehicle-mounted device 3b. In this case, such as Figure 10As shown, the target time point of the second relay frame is 60. Assume the width of the count value corresponding to the entire period is 30. In this case, the transmission indication value of the relay frame is 30 (=60-30). Assume the relay frame stored in the device storage unit 32 is the first relay frame whose transmission target is the vehicle-mounted device 3b. In this case, the target time point of the first relay frame is zero. When the count is 120, the transmission indication value of the relay frame is 90 (=0-30+120).

[0204] Next, the device control unit 33 determines whether the count value from the counter 30 is the relay frame transmission indication value determined in step S61 (step S62). If the device control unit 33 determines that the count value is not the relay frame transmission indication value (S62: No), it executes step S62 again and waits until the count value becomes the transmission indication value determined in step S61.

[0205] If the device control unit 33 determines that the count value is a relay frame transmission indication value (S62: Yes), it instructs the device communication IC 31 to send the relay frame stored in the device storage unit 32 to the relay device 2 (step S63). After executing step S63, the device control unit 33 ends the frame transmission process.

[0206] As described above, the device communication IC 31 of the vehicle-mounted device 3a determines the transmission instruction value for sending a relay frame to the relay device 2 based on the determined overall period, in a manner that makes the relay determination time point of the relay frame belong to the open period.

[0207] The relay frame transmission processing of vehicle-mounted devices 3b and 3c is the same as that of vehicle-mounted device 3a.

[0208] (Implementation Method 2)

[0209] In the pattern data of Implementation Method 1, the total number of open and closed periods included in the i-th cycle is 2 to the power of i. As mentioned above, i is any natural number less than or equal to K. However, in the pattern data, the total number of open and closed periods included in the i-th cycle is not limited to 2 to the power of i.

[0210] The differences between Embodiment 2 and Embodiment 1 will be explained below. Since the structures other than those described later are the same as those in Embodiment 1, the structural parts that are the same as those in Embodiment 1 will be labeled with the same reference numerals as those in Embodiment 1, and their descriptions will be omitted.

[0211] <Content of pattern data>

[0212] Figure 21 This is an explanatory diagram of the content of the pattern data in Implementation Method 2. Figure 21The example shown has a count of 210 and K = 4. In the pattern data of Implementation 2, the total number of on and off periods in each cycle is a prime number. Figure 21 In the example, the total number of the first, second, third, and fourth cycles are 2, 3, 5, and 7, respectively. For the K cycles, the positions of the boundaries between the open and closed periods are all different.

[0213] In the i-th cycle of the pattern data, the open and close periods are configured such that the number of each open and close period within the common range of the first to (i-1)-th cycles is less than 1. Figure 21 In the example, the multiple periods contained in each cycle are of the same length.

[0214] <Changes in the period of the pattern data>

[0215] In step S24 of the period change processing, the device control unit 23 of the relay device 2 changes the period according to the mode data, similar to Embodiment 1. Therefore, for K cycles, the device control unit 23 changes the position of the boundary within each cycle in such a way that the position of the boundary between the open period and the close period is different for each cycle.

[0216] In the pattern data of implementation method 1, such as Figure 16 As shown, the boundaries of the three cycles coincide at 60 (count value). Therefore, when the communication determination time point varies around 60, the period to which the communication determination time point belongs is not fixed in each of the first, second, and third cycles. Therefore, the device control unit 23 cannot accurately determine the range to which the communication determination time point belongs based on the K periods determined in the K cycles. However, in Embodiment 2, the positions of the boundaries between the open and closed periods are different for each of the K cycles. Therefore, even when the communication determination time point varies, the device control unit 23 can accurately determine the range.

[0217] Furthermore, similar to Implementation 1, the lengths of the multiple periods included in each cycle can also differ from the lengths of at least one of the other periods. Therefore, in the pattern data, the lengths of the multiple open periods and multiple closed periods included in the K cycles can be adjusted in a manner consistent with the lengths of all common ranges related to the K cycles. Additionally, the total number of open periods and closed periods in each cycle can also be non-prime.

[0218] <The Effects of Communication System 1>

[0219] The communication system 1 in embodiment 2 also has the same effect as the communication system 1 in embodiment 1.

[0220] (Implementation Method 3)

[0221] In Embodiment 1, the device control unit 23 of the relay device 2 performs communication frame relay processing for each of the transmission buffers Ta, Tb, and Tc, thereby notifying the device control units 33 of each of the vehicle-mounted devices 3a, 3b, and 3c of the period to which the communication determination time point belongs. However, the method for notifying the period to which the communication determination time point belongs is not limited to this method.

[0222] The differences between Embodiment 3 and Embodiment 1 will be explained below. Since the structures other than those described later are the same as those in Embodiment 1, the structural parts that are the same as those in Embodiment 1 will be labeled with the same reference numerals as those in Embodiment 1, and their descriptions will be omitted.

[0223] <Structure of Relay Device 2>

[0224] In Embodiment 2, the processing element (computer) of the device control unit 23 executes the period notification processing for each of the transmission buffers Ta, Tb, and Tc by executing the computer program Pr, instead of the communication frame relay processing for each of the transmission buffers Ta, Tb, and Tc. In each of the three period notification processes, the device control unit 23 notifies the on-board devices 3a, 3b, and 3c of the period to which the communication determination time point belongs.

[0225] <Processing of Notifications During the Period>

[0226] Figure 22 This is a flowchart illustrating the steps of the period notification processing for the transmission buffer Ta in Embodiment 3. During the period notification processing for the transmission buffer Ta, the device control unit 23 of the relay device 2 determines whether a communication frame is stored in the communication queue Qm of the transmission buffer Ta (step S71). If the device control unit 23 determines that no communication frame is stored in the communication queue Qm (S71: No), it executes step S71 again, waiting until a communication frame is written into the communication queue Qm.

[0227] When the device control unit 23 determines that a communication frame is stored in the communication queue Qm (S71: Yes), it reads the count value of the main counter 20 (step S72). The count value read in step S72 corresponds to the communication determination time point at which it was determined that a communication frame is stored in the communication queue Qm. Next, the device control unit 23 determines the period to which the count value read in step S72 belongs during the opening and closing periods of the communication queue Qm (step S73).

[0228] Next, the device control unit 23 instructs the device communication IC 21a to send period data representing the period determined in step S33 (step S74). The period data, for example, indicates the number of times the device control unit 23 determined the on-time (or off-time) period. The device control unit 33 of the vehicle-mounted device 3a can identify the period determined by the device control unit 23 based on whether the number represented by the period data increases. After executing step S74, the device control unit 23 ends the period notification processing of the transmission buffer Ta. Then, the device control unit 23 executes the period notification processing of the transmission buffer Ta again.

[0229] As described above, whenever a communication frame is received from the device communication IC 31 of the vehicle-mounted device 3a, the device communication IC 21a sends period data to the device communication IC 31. Thus, the period determined by the device control unit 23 is notified to the vehicle-mounted device 3a.

[0230] The period notification processing for each of the transmit buffers Tb and Tc is the same as that for the transmit buffer Ta. Device communication IC 21a corresponds to device communication ICs 21b and 21c. Vehicle-mounted device 3a corresponds to vehicle-mounted devices 3b and 3c. In embodiment 3, the relay device 2 does not need to send communication frames to vehicle-mounted devices 3a, 3b, and 3c.

[0231] <Decisions during the overall period>

[0232] Figure 23 This is a flowchart illustrating the steps of the time determination process for the vehicle-mounted device 3a. When comparing Embodiment 3 with Embodiment 1, the content of the time determination process differs. In the time determination process of the vehicle-mounted device 3a in Embodiment 3, the device control unit 33 executes steps S41-S44 and S46-S53 in the same manner as in Embodiment 1. Therefore, their detailed descriptions are omitted.

[0233] In the period determination process of the vehicle-mounted device 3a, after executing step S44, the device control unit 33 determines whether the device communication IC 31 has received period data from the device communication IC 21a of the relay device 2 (step S81). If the device control unit 33 determines that the device communication IC 31 has not received period data (S81: No), it executes step S81 and waits until the device communication IC 31 receives period data.

[0234] When the device control unit 33 determines that the device communication IC 31 has received period data (S81: Yes), it writes the period data received by the device communication IC 31 into the device storage unit 32 (step S82). After executing step S82, the device control unit 33 executes step S46. In step S48, based on the K periods represented by the K periods of data stored in the device storage unit 32, the range to which the communication determination time point belongs is determined.

[0235] As described above, the device control unit 33 determines the range to which the communication determination time point belongs based on K period data.

[0236] In embodiment 3, the period determination processing of each of the vehicle-mounted devices 3b and 3c is the same as that of the vehicle-mounted device 3a. Device communication IC 21a corresponds to device communication ICs 21b and 21c.

[0237] <Effects and Notes of Communication System 1>

[0238] The communication system 1 in embodiment 3 also has the same effect as the communication system 1 in embodiment 1.

[0239] Furthermore, in embodiment 3, the pattern data from embodiment 2 can also be used.

[0240] (Implementation Method 4)

[0241] In implementation 1, the transmission indication value of the relay frame is determined based on the overall duration. However, the object determined based on the overall duration may also be different from the transmission indication value of the relay frame.

[0242] The differences between Embodiment 4 and Embodiment 1 will be explained below. Since the structures other than those described later are the same as those in Embodiment 1, the structural parts that are the same as those in Embodiment 1 will be labeled with the same reference numerals as those in Embodiment 1, and their descriptions will be omitted.

[0243] <Initial Settings>

[0244] Figure 24 This is a flowchart illustrating the initial setup steps performed on the relay device 2 and the vehicle-mounted device 3a in Embodiment 4. When comparing Embodiment 4 with Embodiment 1, the data transmission processing and adjustment processing differ. In the data transmission processing, the device control unit 23 of the relay device 2 executes steps S1 to S4 in the same manner as in Embodiment 1. In the adjustment processing, the device control unit 33 of the vehicle-mounted device 3a executes steps S11 to S15 in the same manner as in Embodiment 1. Therefore, detailed descriptions of steps S1 to S4 and S11 to S15 are omitted.

[0245] During the adjustment process, after executing step S15, the device control unit 33 instructs the device communication IC 31 to send the transmission instruction value data of the vehicle-mounted device 3a to the device communication IC 21a of the relay device 2 (step S101). The transmission instruction value data of the vehicle-mounted device 3a represents the transmission instruction value of the relay frame transmitted by the vehicle-mounted device 3a. After executing step S101, the device control unit 33 ends the adjustment process. The transmission instruction value of the relay frame is predetermined. The transmission instruction value data is pre-stored in the device storage unit 32.

[0246] In the data transmission process, after executing step S4, the device control unit 23 determines whether the device communication IC 21a has received the transmission instruction value data of the vehicle device 3a from the device communication IC 31 of the vehicle device 3a (step S91). If the device control unit 23 determines that the device communication IC 21a has not received the transmission instruction value data of the vehicle device 3a (S91: No), it executes step S91 again and waits until the device communication IC 21a receives the transmission instruction value data of the vehicle device 3a.

[0247] When the device control unit 23 determines that the device communication IC 21a has received the transmission instruction value data from the vehicle-mounted device 3a (S91: Yes), it writes the transmission instruction value data received by the device communication IC 21a from the vehicle-mounted device 3a into the device storage unit 22 (step S92). After executing step S92, the device control unit 33 ends the adjustment process.

[0248] As described above, after the device control unit 23 and the vehicle-mounted device 3a have been initially set, the transmission instruction value data of the vehicle-mounted device 3a is stored in the device storage unit 22. The count value of the slave counter 30 is synchronized with the count value of the master counter 20.

[0249] The initial settings of relay device 2 with vehicle-mounted devices 3b and 3c are the same as the initial settings of relay device 2 with vehicle-mounted device 3a. The connection connector 2a and device communication IC 21a of vehicle-mounted device 3a correspond to the connection connector 2b and device communication IC 21b of vehicle-mounted device 3b, respectively. Furthermore, the connection connector 2a and device communication IC 21a of vehicle-mounted device 3a correspond to the connection connector 2c and device communication IC 21c of vehicle-mounted device 3c, respectively.

[0250] <An overview of the methods for determining the overall period>

[0251] Figure 25This is a timing diagram outlining the method for determining the overall duration of the vehicle-mounted device 3a. In Embodiment 4, after initial setup, it is not the vehicle-mounted device 3a, but the relay device 2 that sends start data. Upon receiving the start data, the vehicle-mounted device 3a waits until the count value of the counter 30 becomes zero. When the count value becomes zero, the vehicle-mounted device 3a sends a communication frame to the relay device 2. Thereafter, the vehicle-mounted device 3a sends a communication frame to the relay device 2 whenever the count value becomes zero.

[0252] After transmitting the start data, relay device 2 waits until the count value of the main counter 20 becomes zero. When the count value becomes zero, relay device 2 begins changing the duration according to the pattern data. Relay device 2 performs N changes according to the duration of the pattern data. Whenever a communication frame is received from the vehicle-mounted device 3a, relay device 2 determines the communication determination time point (count value) of the received communication frame within the open and closed periods of the communication queue Qm in the transmit buffer Ta.

[0253] The vehicle-mounted device 3a sends (K·N) communication frames to the relay device 2. Based on the (K·N) determination results, the relay device 2 determines N ranges to which the communication determination time point belongs. The relay device 2 determines the overall duration of the vehicle-mounted device 3a based on the determined N ranges. The determination of the ranges performed by the relay device 2 is the same as that performed by the vehicle-mounted device 3a in Embodiment 1. The determination of the overall duration performed by the relay device 2 is the same as that performed by the vehicle-mounted device 3a in Embodiment 1.

[0254] The method for determining the overall duration of vehicle-mounted devices 3b and 3c is the same as the method for determining the overall duration of vehicle-mounted device 3a.

[0255] The following describes the specific processing performed on the device control unit 23 of relay device 2 and the vehicle-mounted equipment 3a, 3b, and 3c regarding the method for determining the overall duration.

[0256] <Changes in the period of the pattern data>

[0257] Figure 26 This is a flowchart illustrating the steps of the period change processing corresponding to the communication queue Qm of the transmit buffer Ta. When comparing Embodiment 4 with Embodiment 1, the content of the period change processing differs. In the period change processing of Embodiment 4, the device control unit 23 of the relay device 2 executes steps S22 to S26 in the same manner as in Embodiment 1. Therefore, their detailed descriptions are omitted.

[0258] During the change processing, firstly, the device control unit 23 instructs the device communication IC 21a to send start data to the device communication IC 31 of the vehicle-mounted device 3a (step S111). After executing step S111, the device control unit 23 executes step S22.

[0259] The period change processing corresponding to the communication queue Qm of the transmit buffers Tb and Tc is the same as the period change processing corresponding to the communication queue Qm of the transmit buffer Ta. Device communication IC21a corresponds to device communication ICs 21b and 21c. Onboard device 3a corresponds to onboard devices 3b and 3c.

[0260] <Structure of vehicle-mounted equipment 3a, 3b, and 3c>

[0261] In Embodiment 4, the processing element (computer) of the device control unit 33 executes the communication frame transmission process by executing the computer program Pe, instead of the processing determined during the process.

[0262] <Communication Frame Transmission Processing>

[0263] Figure 27 This is a flowchart illustrating the steps of the communication frame transmission processing of the vehicle-mounted device 3a. After initial settings are performed, the communication frame transmission processing of the vehicle-mounted device 3a is executed by the device control unit 33. Similar to Embodiment 1, the values ​​of variables X and Y are stored in the device storage unit 32 of the vehicle-mounted device 3a. During the communication frame transmission processing of the vehicle-mounted device 3a, the device control unit 33 executes steps S41, S43, S44, and S46 to S51 of the period determination processing in Embodiment 1. Therefore, detailed descriptions of these steps are omitted.

[0264] In the communication frame transmission processing of the vehicle-mounted device 3a, the device control unit 33 first determines whether the device communication IC 31 has received the start data (step S121). If the device control unit 33 determines that the device communication IC 31 has not received the start data (S121: No), it executes step S121 again and waits until the device communication IC 31 receives the start data. If the device control unit 33 determines that the device communication IC 31 has received the start data (S121: Yes), it executes step S41.

[0265] After executing step S41, the device control unit 33 executes step S43. After executing step S44, the device control unit 33 executes step S46. If the device control unit 33 determines that the value of variable Y is N (S51: Yes), the device control unit 33 terminates the communication frame transmission process.

[0266] The communication frame transmission processing of vehicle-mounted devices 3b and 3c is the same as that of vehicle-mounted device 3a. Device communication IC21a corresponds to device communication ICs 21b and 21c.

[0267] <Transmission of relay frames by vehicle-mounted equipment 3a, 3b, and 3c>

[0268] The relay frame transmission processing of vehicle-mounted equipment 3a, 3b, and 3c (refer to...) Figure 20 In this embodiment, the device control unit 33 does not execute step S61, but executes steps S62 and S63. The transmission instruction value in step S62 is the transmission instruction value represented by the transmission instruction value data. The device communication IC 31 of each of the vehicle-mounted devices 3a, 3b, and 3c transmits a relay frame when the count value becomes the transmission instruction value represented by the transmission instruction value data. In embodiment 4, target data is not used.

[0269] <Structure of Relay Device 2>

[0270] In Embodiment 4, the processing element (computer) of the device control unit 23 further executes the period adjustment processing for each of the transmit buffers Ta, Tb, and Tc by executing the computer program Pr. The period adjustment processing adjusts the start time or length of the opening period for each of the first queue Q1 and the second queue Q2. The device storage unit 22 stores the values ​​of the variables Fa, Ga, Fb, Gb, Fc, and Gc used in the three period adjustment processes. These values ​​are changed by the device control unit 23.

[0271] <Period Adjustment Processing>

[0272] Figure 28 This is a flowchart illustrating the steps of the period adjustment process for the transmission buffer Ta. After initial settings are performed, the period adjustment process for the transmission buffer Ta is executed by the device control unit 23 in parallel with the communication frame transmission process of the vehicle-mounted device 3a. In the period adjustment process for the transmission buffer Ta, the device control unit 23 first sets the values ​​of variables Fa and Ga to zero (step S131). Next, the device control unit 23 determines whether a communication frame is stored in the communication queue Qm of the transmission buffer Ta (step S132). If the device control unit 23 determines that no communication frame is stored in the communication queue Qm (S132: No), it waits until a communication frame is stored in the communication queue Qm.

[0273] When the device control unit 23 determines that a communication frame is stored in the communication queue Qm (S132: Yes), it reads the count value of the main counter 20 (step S133). The count value read in step S133 corresponds to the communication determination time point at which the communication frame is determined to be stored in the communication queue Qm. Next, the device control unit 23 determines the period to which the count value read in step S133 belongs during the open and closed periods of the communication queue Qm (step S134). After executing step S134, the device control unit 23 increments the value of the variable Fa by 1 (step S135) and determines whether the value of the variable Fa is K (step S136).

[0274] If the device control unit 23 determines that the value of variable Fa is not K (S136: No), it executes step S132 again to determine the period to which the communication determination time point of the next received communication frame belongs. As described above, the K periods to which the communication determination time points of K communication frames belong are determined.

[0275] If the device control unit 23 determines that the value of variable Fa is K (S136: Yes), it determines the range to which the communication determination time point belongs within one cycle based on the determined K periods (step S137). The range determination performed by the device control unit 23 is the same as the range determination performed by the device control unit 33 of the vehicle-mounted device 3a. Next, the device control unit 23 sets the value of variable Fa to zero (step S138) and increments the value of variable Ga by 1 (step S139). After executing step S139, the device control unit 23 determines whether the value of variable Ga is N (step S140).

[0276] If the device control unit 23 determines that the value of variable Ga is not N (S140: No), it executes step S132 again. The device control unit 23 redetermines the K periods to which the communication determination time point belongs, and redetermines the range based on the determined K periods. As described above, the device control unit 23 determines the range N times. If the device control unit 23 determines that the value of variable Ga is N (S140: Yes), it determines the overall period of the vehicle-mounted device 3a based on the determined N ranges (step S141). The determination of the overall period performed by the device control unit 23 is the same as the determination of the overall period performed by the device control unit 33 of the vehicle-mounted device 3a.

[0277] Next, the device control unit 23 adjusts the opening periods of the first queue Q1 and the second queue Q2 of the transmission buffer Ta based on the overall period determined in step S141 (step S142). The adjustment of the opening period is an adjustment of the start time or length of the opening period. In one cycle, the period other than the opening period is the closing period. Therefore, when the start time and length of the opening period are determined, the start time and length of the closing period are automatically determined. The on-board devices 3a, 3b, and 3c transmit the first relay frame or the second relay frame when the count value from the counter 30 is the transmission instruction value represented by the transmission instruction value data.

[0278] In step S142, for the transmission buffer Ta, the device control unit 23 adjusts the start time or length of the opening period of the first relay queue Q1 so that the relay determination time point of all first relay frames whose transmission target is the vehicle-mounted device 3a belongs to the opening period of the first queue Q1. Additionally, for the transmission buffer Ta, the device control unit 23 adjusts the start time or length of the opening period of the second queue Q2 so that the relay determination time point of all second relay frames whose transmission target is the vehicle-mounted device 3a belongs to the opening period of the second queue Q2. After executing step S142, the device control unit 23 ends the period adjustment process.

[0279] The period adjustment processing for transmit buffers Tb and Tc is the same as that for transmit buffer Ta. Onboard device 3a corresponds to onboard devices 3b and 3c. Variable Fa corresponds to variables Fb and Fc. Variable Ga corresponds to variables Gb and Gc.

[0280] <Effects and Notes of Communication System 1>

[0281] The communication system 1 in embodiment 4 also has the same effects as the communication system 1 in embodiment 1, except for the effects obtained by adjusting the transmission indication value of the relay frame.

[0282] Furthermore, in embodiment 4, the pattern data from embodiment 2 can also be used.

[0283] <Variations of Embodiments 1-4>

[0284] In embodiments 1 to 4, device communication ICs 21a, 21b, and 21c each have a processing element for performing processing. Each of the device communication ICs 21a, 21b, and 21c can also replace the device control unit 23 to perform a portion of the aforementioned processing performed by the device control unit 23. In this case, the entirety of the device communication ICs 21a, 21b, and 21c and the device control unit 23, or one of the device communication ICs 21a, 21b, and 21c, functions as a processing unit or a relay processing unit. Similarly, device communication IC 31 has a processing element for performing processing. Device communication IC 31 can also replace the device control unit 33 to perform a portion or all of the aforementioned processing performed by the device control unit 33. In this case, both the device communication IC 31 and the device control unit 33, or the device communication IC 31 itself, functions as a communication processing unit.

[0285] The transmission indication value for the communication frame can also be a value other than zero. Furthermore, if the variation in the communication determination time point is small, N can also be 1. In this case, the calculated value for the entire period is, for example, determined to be the central value of the determined range. Moreover, vehicle-mounted devices 3a, 3b, and 3c can each transmit multiple first relay frames during the opening of the first queue Q1. Similarly, vehicle-mounted devices 3a, 3b, and 3c can each transmit multiple second relay frames during the opening of the second queue Q2.

[0286] When the relay determination time point falls within a closed period, the processing is not limited to discarding the relay frame; it can also include retaining the transmission of the relay frame. In this case, for example, the relay frame is not transmitted until the next open period arrives. When the next open period arrives, the transmitted relay frame that was retained is transmitted. The number of queues for relay frames set in the transmission buffers Ta, Tb, and Tc is not limited to two, but can be three or more. The number of vehicle-mounted devices connected to the relay device 2 is not limited to three, but can be four or more.

[0287] The disclosed embodiments 1 to 4 should be considered illustrative in all respects and not restrictive. The scope of the invention is not as described above, but is set forth in the claims and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0288] Label Explanation

[0289] 1. Communication System

[0290] 2 Relay device

[0291] 2a, 2b, 2c Connector

[0292] 3a, 3b, 3c Vehicle-mounted equipment (communication devices)

[0293] 20 main counter

[0294] Communication ICs (Receiver Unit, Relay Receiver Unit) for devices 21a, 21b, and 21c

[0295] 22. Device storage section (storage section, relay storage section)

[0296] 23. Device Control Unit (Processing Unit, Relay Processing Unit)

[0297] 24 Device Bus

[0298] 30 from counter

[0299] 31 Device Communication IC

[0300] 32 Equipment Storage Department

[0301] 33 Equipment Control Department (Communication Processing Department)

[0302] 34 Device Bus

[0303] Ae, Ar storage media

[0304] B Device Connector

[0305] E1, E2 range

[0306] M vehicle

[0307] Pe, Pr computer programs

[0308] Q1 First Queue

[0309] Q2 Second Queue

[0310] Qm communication queue

[0311] Ra, Rb, Rc receive buffers

[0312] Ta, Tb, Tc send buffers.

Claims

1. A relay device for relaying communications, wherein, The relay device includes: The receiving unit receives communication data from the communication device; The storage unit stores the communication data received by the receiving unit; and Processing Department, Execute Processing Alternately set the first period and the second period. Whenever the processing unit passes through a predetermined period that includes the first period and the second period, it changes the total number of the first period and the second period included in the next predetermined period. The processing unit determines whether the communication data is stored in the storage unit. When the processing unit determines that the communication data is stored in the storage unit, it determines the period to which the communication determination time point belongs in the first period and the second period.

2. The relay device according to claim 1, wherein, The processing unit changes the total number for each specified period in such a way that the total numbers for each of a plurality of consecutive specified periods are different from each other. For the plurality of specified periods, the processing unit changes the position of the boundary within each specified period in such a way that the position of the boundary between the first period and the second period is different from that of each other.

3. The relay device according to claim 1 or claim 2, wherein, The processing unit changes the total number of each specified period in such a way that the total number contained in each of a plurality of consecutive specified periods is different from that of each other. The processing unit repeats the multiple specified periods multiple times.

4. The relay device according to any one of claims 1 to 3, wherein, The receiving unit receives communication data from the communication device each time the predetermined period elapses. The processing unit changes the total number of each specified period in such a way that the total number contained in each of a plurality of consecutive specified periods is different from that of each other. After the aforementioned multiple specified periods have elapsed, the processing unit determines the range to which the communication determination time point belongs within the specified periods based on multiple determination results related to the periods. The processing unit determines the entire period from the time the communication device instructs the transmission of communication data until the communication determination time point, based on the determined range.

5. The relay device according to claim 4, wherein, The receiving unit receives relay data for relay purposes. The received relay data is stored in the storage unit. Alternately set an allow period and a prohibition period, during which the transmission of the relay data is permitted, and during the prohibition period, the transmission of the relay data is prohibited. The processing unit determines whether the relay data is stored in the storage unit. If the processing unit determines that the relay data is stored in the storage unit, it determines the period to which the relay determination time point belongs between the permitted period and the prohibited period. If the determined period falls within the permitted period, the processing unit instructs the transmission of the relay data. The processing unit adjusts the start time or length of the allowed period based on the determined overall period.

6. A communication system, comprising: Communication devices, for transmitting data; and The relay device receives data from the communication device and transmits the received data. The communication device includes a communication processing unit, which performs processing. The communication processing unit instructs the relay device to send communication data. The relay device has: The relay receiving unit receives the communication data from the communication device; The relay storage unit stores the communication data received by the relay receiving unit; and Relay processing department, performing the processing. Alternately set the first period and the second period. Whenever the relay processing unit passes through a predetermined period that includes both the first and second periods, it changes the total number of the first and second periods included in the next predetermined period. The relay processing unit determines whether the communication data is stored in the relay storage unit. When the relay processing unit determines that the communication data is stored in the relay storage unit, it determines the period to which the determined communication determination time point belongs in the first period and the second period.

7. The communication system according to claim 6, wherein, The communication processing unit instructs the relay receiving unit to send communication data each time the specified period elapses. The relay processing unit changes the total number of each specified period in such a way that the total number contained in each of a plurality of consecutive specified periods is different from that of each other. After the specified periods have elapsed, the communication processing unit, based on multiple determination results determined by the relay processing unit, determines the range to which the communication determination time point belongs within the specified periods. The communication processing unit determines the entire period from the date of sending the instruction communication data to the date of the communication determination, based on the determined range.

8. The communication system according to claim 7, wherein, The communication processing unit instructs the relay receiving unit to send relay data for relay purposes. The relay storage unit stores the relay data received by the relay receiving unit. Alternately set an allow period and a prohibition period, during which the transmission of the relay data is permitted, and during the prohibition period, the transmission of the relay data is prohibited. The relay processing unit determines whether the relay data is stored in the relay storage unit. If the relay processing unit determines that the relay data is stored in the relay storage unit, it determines the period to which the relay determination time point belongs between the permitted period and the prohibited period. If the determined period falls within the permitted period, the relay processing unit instructs the transmission of the relay data. The communication processing unit determines the transmission instruction time point for instructing the transmission of the relay data based on the overall period determined.

9. The communication system according to claim 7 or claim 8, wherein, When the determined period is the first period, the relay processing unit instructs the communication device to send the communication data received by the relay receiving unit. If the determined period is the second period, the relay processing unit discards the communication data received by the relay receiving unit. After the specified periods have elapsed, the communication processing unit determines the range to which the communication determination time point belongs within the specified periods based on the multiple reception results of the communication data.

10. A processing method for a relay device, the relay device comprising: a receiving unit for receiving communication data from a communication device; and a storage unit for storing the communication data received by the receiving unit, wherein the relay device performs communication relay, wherein... The computer performs the following steps: Each time a specified period consisting of alternating first and second periods is elapsed, the total number of the first and second periods included in the next specified period is changed; Determine whether the communication data is stored in the storage unit; and If it is determined that the communication data is stored in the storage unit, the period to which the communication determination time point belongs in the first period and the second period is determined.

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