Inspection device and inspection method

Abstract

To provide an inspection technique capable of inspecting a CAN communication function in an ECU.SOLUTION: An inspection apparatus, that inspects a CAN communication function of an ECU to be inspected, comprises: a connection unit configured to connect a communication circuit of the ECU and the inspection apparatus on a one-to-one basis: an inspection message creation unit configured to create an inspection message in which a predetermined signal level indicating a higher priority of communication arbitration than a message received from the ECU to be inspected is set in an identifier field of a data format corresponding to the message; a transmission unit configured to transmit the inspection message to the ECU; a reception unit configured to receive a message transmitted from the ECU; and a reception function determination unit configured to determine whether a reception function of the ECU is normal on the basis of whether the reception unit has received the message from the ECU after the transmission of the inspection message.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an inspection device and an inspection method. [Background technology]

[0002] Conventionally, vehicles are equipped with multiple electronic devices that perform various processes. To control the operation of these electronic devices, vehicles are equipped with multiple ECUs (Electronic Control Units). To enable the multiple ECUs to operate in coordination, the ECUs are interconnected via a network, and data is sent and received so that the multiple ECUs can share information. CAN (Controller Area Network) is widely used as the communication protocol.

[0003] Patent document 1 discloses a communication load determination device used in a communication system that follows a communication protocol in which multiple communication devices (ECUs) communicate via a common bus, a priority is assigned to each frame sent from the communication device, and frames with lower priority have a longer waiting time before being sent to the bus. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 05578207 Specification Summary of the Invention [Problem to be solved by the invention]

[0005] Since it is not possible to inspect the internal components of electric vehicles, such as the IPU (Integrated Power Unit), DU (Drive Unit), and CHGR (Charger), in order to identify defective devices, a non-defective device replacement test is conducted in which normally functioning devices are sequentially replaced to see if the test information improves.

[0006] However, in an inspection for replacing non-defective devices, it is necessary to prepare each expensive device for inspection, and the inspection work also requires a certain number of steps for the device replacement work.

[0007] On the other hand, the communication load determination device of Patent Document 1 determines whether a communication load is abnormal based on whether the average waiting time until transmission exceeds the allowable waiting time, according to the rule of transmitting messages first with higher priority, and is unable to determine whether the CAN communication function (receiving function) in the ECU is normal.

[0008] In view of the above-mentioned problems, the present invention aims to provide an inspection technique that can inspect the CAN communication function of an ECU to be inspected. [Means for solving the problem]

[0009] An inspection device according to one embodiment of the present invention is an inspection device that inspects the CAN communication function of an ECU to be inspected, and includes a connection unit that connects the communication circuit of the ECU to the inspection device on a one-to-one basis, an inspection message creation unit that creates an inspection message in which a predetermined signal level indicating a higher communication arbitration priority than a message is set in an identifier field of a data format corresponding to the message received from the ECU to be inspected, a transmission unit that transmits the inspection message to the ECU, a reception unit that receives the message transmitted from the ECU, and a reception function determination unit that determines whether the receiving function of the ECU is normal or not based on whether the reception unit receives a message from the ECU after transmitting the inspection message. a judgment time changing unit that changes a continuous judgment time for determining whether the CAN communication function is normal or not from a first continuous judgment time to a second continuous judgment time that is shorter than the first continuous judgment time, in response to an input from a sensitivity switching unit; Equipped with.

[0010] Another aspect of the present invention provides an inspection method for an inspection device that is connected one-to-one to a communication circuit of an ECU under test via a connection unit and inspects the CAN communication function of the ECU under test, the inspection method comprising the steps of: an inspection message creation unit of the inspection device creating an inspection message in which a predetermined signal level indicating a higher communication arbitration priority than a message is set in an identifier field of a data format corresponding to the message received from the ECU under test; a transmission unit of the inspection device transmitting the inspection message to the ECU; a reception unit of the inspection device receiving the message transmitted from the ECU; and a reception function determination unit of the inspection device determining whether the reception function of the ECU is normal or not, based on whether a message has been received from the ECU in the reception step after transmitting the inspection message. a step in which a judgment time changing unit of the inspection device changes a continuous judgment time for determining whether the CAN communication function is normal or not from a first continuous judgment time to a second continuous judgment time that is shorter than the first continuous judgment time, based on an input from a sensitivity switching means; It has. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide an inspection technique that can inspect the CAN communication function of an ECU to be inspected. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of an inspection system including an inspection apparatus according to an embodiment. [Figure 2] FIG. 2 is a diagram showing an example of the circuit configuration of an ECU to be inspected. [Figure 3] FIG. 2 is a diagram showing the functional configuration of an inspection apparatus according to an embodiment. [Figure 4] FIG. 2 is a diagram illustrating the flow of an inspection using the inspection device of the embodiment. [Figure 5] FIG. 10 is a diagram schematically illustrating the flow of receiving a message, determining the data format of the message, and generating a test message. [Figure 6A] FIG. 2 is a diagram showing an example of the data format of an inspection message based on the CAN protocol. [Figure 6B] FIG. 10 is a diagram showing an example of the data format of an inspection message based on the CAN FD protocol. [Figure 7]A diagram showing a schematic flow of sending an inspection message, checking whether a message has been sent from the ECU, and judging the receiving function. [Figure 8] A diagram showing an example of setting an identifier field (ID field). [Figure 9] FIG. 10 is a diagram illustrating the flow of a bit rate determination process. [Figure 10] FIG. 10 is a diagram illustrating the flow of processing for determining a data format. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention as claimed, and not all combinations of features described in the embodiments are necessarily essential to the invention. Two or more of the features described in the embodiments may be arbitrarily combined. Furthermore, the same reference numerals are used for the same or similar components, and redundant explanations will be omitted.

[0014] [Schematic configuration of inspection system including inspection device 10] FIG. 1 is a diagram showing a schematic configuration of an inspection system including an inspection device 10 according to an embodiment. In FIG. 1, an ECU included in a device 20 is exemplarily shown as an ECU 200 to be inspected. The device 20 may be, for example, an IPU (Integrated Power Unit), a DU (Drive Unit), or a CHGR (Charger). The inspection device 10 of this embodiment is an inspection device that inspects the CAN communication function of the ECU 200 to be inspected. The inspection device 10 has a CAN communication unit 100 and a power supply unit 105.

[0015] When devices 20 such as IPUs and DUs are connected to the CAN in a vehicle, the ECU of each device 20 functions as a communication node, but here, the CAN connection coupler is removed, and the inspection device 10 and the ECU 200 (communication circuit 210) to be inspected are connected one-to-one, and the CAN communication function of the ECU 200 to be inspected is inspected by checking the signal (message) from the ECU 200 to be inspected.

[0016] The connection unit 30 connects the inspection device 10 (CAN communication unit 100) and the ECU 200 (communication circuit 210) to be inspected in a one-to-one relationship via a connection coupler 34. The connection unit 30 has CANL 31 and CANH 32 as bus signal lines for CAN communication.

[0017] The power supply unit 105 can supply the power supply voltage VCC, which is converted from an external power supply to a predetermined voltage (for example, 12 V), to the ECU 200 under test via the power supply line 33. The connection unit 30 may include bus signal lines 31 and 32 and the power supply line 33. The power supply voltage VCC does not necessarily have to be supplied from the power supply unit 105, but may also be supplied to the ECU 200 under test from the vehicle side. When the power supply voltage VCC is supplied from the vehicle side, the power supply line 33 is not essential, and the connection unit 30 may be configured to include at least the bus signal lines 31 and 32.

[0018] [ECU200 to be inspected] 2 is a diagram showing an example of the circuit configuration of ECU 200 to be inspected. ECU 200 has a communication circuit 210 and a controller 240. Communication circuit 210 has a transmission circuit 220 that performs processing to transmit messages based on signals output from ECU 200, and a reception circuit 230 that performs processing to receive signals (messages) received from the outside. Controller 240 is a control unit that controls the operations of transmission circuit 220 and reception circuit 230 in communication circuit 210.

[0019] The bus signal line 31 (CANL) of the connection unit 30 is a signal line on the low potential side, and the bus signal line 32 (CANH) is a signal line on the high potential side compared to the bus signal line 31. The potential is a potential based on the ground potential (i.e., earth potential) of the inspection device 10.

[0020] The transmission circuit 220 receives a transmission signal TXD from the controller 240, and outputs a signal (message) including a high or low signal level that is generated based on the transmission signal TXD. The reception circuit 230 converts the signal (message) including a high or low signal level that is received from the bus signal lines 31 and 32 into a reception signal RXD, and outputs the converted reception signal RXD to the controller 240.

[0021] Regarding signal levels, a high level corresponds to, for example, a logical value of 1 as a data value, and corresponds to a recessive level (CANH: 32) as a potential of the bus signal line. A low level corresponds to, for example, a logical value of 0 as a data value, and corresponds to a dominant level (CANL: 31) as a potential of the bus signal line. Dominant refers to the signal that is more dominant among the signals transmitted through the bus signal lines 31 and 32, and recessive refers to the signal that is less dominant among the signals transmitted through the bus signal lines 31 and 32. Specific signal processing within the ECU 200 is a well-known technique, and detailed description thereof will be omitted.

[0022] [Inspection device 10] (Functional configuration) 3 is a diagram showing the functional configuration of the inspection device 10 of this embodiment. The inspection device 10 has, as its functional configuration, an initial message confirmation unit 110, a transmission function determination unit 120, an inspection message creation unit 130, a transmission unit 140, a reception unit 150, a reception function determination unit 170, and a determination time change unit 180.

[0023] These functional configurations are realized by reading a predetermined computer program stored in a storage medium of the inspection device 10 into the RAM and executing signal processing by the CPU of the inspection device 10. Furthermore, they may be configured by integrated circuits or the like as long as they perform similar functions.

[0024] (Sensitivity switching function setting) The inspection device 10 of this embodiment can switch the inspection determination time between a standard mode and a sensitive mode using a sensitivity changeover switch (not shown).

[0025] The first continuous judgment time in standard mode (e.g., 1.5 seconds) is set to match the abnormality detection conditions of a standard vehicle. However, actual malfunctions can be difficult to reproduce within the limited inspection time at a repair site. For example, in an unstable state, such as when solder is peeling, the malfunction does not occur continuously, and the standard mode time setting may make it difficult to detect a phenomenon in which the malfunction (abnormality) continues.

[0026] In order to make it easier to detect continuous malfunctions even for ECUs in an operating state where continuous malfunctions are unlikely to occur, the inspection device 10 of this embodiment is provided with a sensitive mode that can perform inspections within a second continuous judgment time (e.g., 0.75 seconds) in the sensitive mode, which is shorter than the signal sampling time in the first continuous judgment time.

[0027] The judgment time change unit 180 changes the continuous judgment time for determining whether the CAN communication function is normal or not from a first continuous judgment time (e.g., 1.5 seconds) in standard mode to a second continuous judgment time (e.g., 0.75 seconds) in sensitive mode, which is shorter than the first continuous judgment time, based on input from the sensitivity changeover switch.

[0028] When the standard mode is set, receiving function determination unit 170 determines whether the receiving function of ECU 200 (receiving circuit 230) is normal based on the first continuous determination time. When the determination time has been changed by determination time change unit 180, that is, when the sensitive mode is set, receiving function determination unit 170 determines whether the receiving function of ECU 200 is normal based on the second continuous determination time.

[0029] If the malfunction state (abnormality) continues during the continuous determination time (first continuous determination time, second continuous determination time), receiving function determination unit 170 determines that the receiving function of ECU 200 is in a malfunction state.

[0030] The switching between the standard mode and the sensitive mode is also performed in the transmission function determination process. That is, when the standard mode is set, the transmission function determination unit 120 determines whether the transmission function of the ECU 200 (transmission circuit 220) is normal or not based on the first continuous determination time. When the determination time is changed by the determination time change unit 180, that is, when the sensitive mode is set, the transmission function determination unit 120 determines whether the transmission function of the ECU 200 is normal or not based on the second continuous determination time. When the malfunction state (abnormality) continues during the continuous determination time (first continuous determination time, second continuous determination time), the transmission function determination unit 120 determines that the transmission function of the ECU 200 is in a malfunction state.

[0031] The sensitivity can be switched at any timing by operating the sensitivity switch. For example, when the sensitivity is switched by operating the sensitivity switch at the start of or during the test, the judgment time changing unit 180 can change the judgment time setting from the first continuous judgment time to the second continuous judgment time. Alternatively, the judgment time changing unit 180 can change the judgment time setting from the second continuous judgment time to the first continuous judgment time.

[0032] [Inspection message data format] Next, the configuration of the data format of the inspection message created by the inspection message creation unit 130 will be described. The following description is an overview of the data format based on the CAN or CAN FD communication protocol, and the data format is also referred to as a data frame. In addition, in the data format (data frame), an area in which bit-by-bit data is set is called a field. The data format (data frame) described in FIGS. 6A and 6B is the data format used when transmitting an inspection message 600 from the inspection device 10 to the ECU 200.

[0033] Fig. 6A is a diagram showing an example of the configuration of the data format (data frame) of an inspection message 600 based on the CAN protocol, which is created by the inspection message creation unit 130. Fig. 6B is a diagram showing an example of the configuration of the data format (data frame) of an inspection message based on the CAN FD protocol, which is created by the inspection message creation unit 130. In Fig. 6A and Fig. 6B, the numerical value of each part of each data format indicates the length (bit length) of the data, i.e., how many bits are used.

[0034] (CAN standard format) 6A, ST61 shows a data frame in a standard format based on the CAN protocol, and ST62 shows a data frame in an extended format based on the CAN protocol. ST62 partially illustrates the configuration from the SOF to the data field, and the configuration after the data field in ST62 is the same as the standard format of ST61.

[0035] In ST61 and ST62 in Figure 6A, the upper line indicates the signal level of the recessive level (logical value 1), and the lower line indicates the signal level of the dominant level (logical value 0). Portions with lines only on the dominant level side indicate data that is fixed to dominant, and portions with lines only on the recessive level side indicate data that is fixed to recessive. Portions with lines on both sides indicate data that changes (is inverted) between dominant and recessive depending on the data being transmitted.

[0036] SOF (Start Of Frame) is a field that indicates the start of data frame transmission. When the signal level of the SOF changes from a recessive level (logical value 1) of bus idle to a dominant level (logical value 0), the ECU 200 under test can synchronize its reception process.

[0037] The ID (Identifier) ​​is used to identify the data content and the transmitting node, as well as to determine the priority of communication arbitration. In this embodiment, the identifier field (ID field) 610 is used as a field for communication arbitration to determine whether the receiving circuit 230 of the ECU 200 has successfully received the data. In the standard format, the identifier field (ID field) 610 is 11 bits long.

[0038] The RTR (Remote Transmission Request) field is used to distinguish between a data frame and a remote frame, where the remote frame is used to request a data frame. The RTR can be used for communication arbitration in the same way as the identifier field (ID field) 610.

[0039] The IDE is a field used to distinguish between standard format (e.g., 11 bits) and extended format (e.g., 29 bits). In standard format, a dominant signal (logic value 0) is set to IDE, and in extended format, a recessive signal (logic value 1) is set to IDE.

[0040] The "r" indicates a reserved bit, and the DLC (Data Length Code) is a field that indicates how many bytes of data will be sent in the following data field. The IDE, reserved bit ("r"), and DLC together are also called the control field.

[0041] The data field is the part of the data to be transmitted, and is the data length set by the DLC. Within the data field, all bytes are transmitted with the most significant bit (MSB) first. The data field is 0 to 8 bytes long (0 to 64 bits long), and the length can be set for each byte.

[0042] CRC (Cyclic Redundancy Check) is a field that indicates the calculation result of the transmitted values ​​of the SOF, ID, control field, and data field. For example, the transmitting node calculates the transmitted values ​​and sets the calculated transmitted values ​​as the CRC. The receiving node calculates the received values ​​of the SOF, ID, control field, and data field in the same way as the transmitting node, and compares them with the CRC set value to determine whether the received message (data) was received correctly.

[0043] For example, if the transmitting node is the ECU 200 to be inspected and the receiving node is the inspection device 10, the receiving unit 150 of the inspection device 10 can determine whether the received message (data) was received correctly by calculating the received values ​​of the SOF, ID, control field, and data field of the received data and comparing them with the CRC setting value. CRC_DEL (CRC delimiter) is a field that indicates the end of the CRC sequence. CRC and CRC_DEL (CRC delimiter) are collectively referred to as the CRC field.

[0044] ACK (ACKnowledge) is a confirmation field for determining whether the data up to the transmitted CRC has been successfully received by the receiving circuit 230 of the destination node (for example, the ECU 200 being inspected). The confirmation field is 1 bit long, and the transmitting node transmits a dominant (logical value 0), and if the receiving node has successfully received the data up to the CRC field, it transmits a recessive (logical value 1) confirmation response. ACK_DEL (ACK delimiter) is a field that indicates the end of the ACK field. ACK and ACK_DEL (ACK delimiter) are collectively referred to as the ACK field. EOF (End Of Frame), which follows ACK_DEL (ACK delimiter), is a field that is sent at the end of the data frame.

[0045] (CAN extended format) The extended format shown in ST62 has a different configuration from the standard format (ST61). The base ID is 11 bits long, and the ID in the standard format is called the base ID in the extended format. In the extended format, the base ID is followed by the Substitute Remote Request Bit (SRR), which is set to a 1-bit recessive signal. Following the SRR is the Identifier Extension Bit (IDE), which is set to a 1-bit recessive signal (logical value 1).

[0046] In the extended format, the identifier field (ID field) 610 is composed of an 11-bit base ID field and an 18-bit extended ID field. That is, in the extended format, the identifier field (ID field) 610 is composed of 29 bits (= 11 bits + 18 bits).

[0047] The reserved bits ("r1", "r0") are each set to a 1-bit dominant signal. The DLC (Data Length Code) is a field that indicates how many bytes of data will be transmitted in the following data field. The reserved bits ("r1", "r0") and DLC together are also called the control field.

[0048] (CAN FD standard format) 6B, ST63 shows a data frame in a standard format based on the CAN FD protocol, and ST64 shows a data frame in an extended format based on the CAN FD protocol. In ST64, the configuration from the SOF to the data field is different from the standard format of ST63, but the configuration after the data field in ST64 is the same as the standard format of ST63.

[0049] In ST63 and ST64 in Figure 6B, the upper line indicates the signal level of the recessive level (logical value 1), and the lower line indicates the signal level of the dominant level (logical value 0). Portions with a line only on the dominant level side indicate data that is fixed to dominant, and portions with a line only on the recessive level side indicate data that is fixed to recessive. Portions with lines on both sides indicate data that changes (inverts) to dominant or recessive depending on the data being transmitted.

[0050] SOF (Start Of Frame) is a field that indicates the start of data frame transmission. When a data frame is transmitted from a node, the first part transmitted is set to a dominant state to indicate the start of the data frame. When the SOF signal level changes from a bus idle recessive level (logical value 1) to a dominant level (logical value 0), the ECU 200 under test can synchronize its reception process.

[0051] The arbitration area of ​​the CAN FD protocol is composed of an ID (Identifier) ​​and an RRS (Remote Request Substitution). As with the CAN protocol, the ID (Identifier) ​​is used to identify data content and transmitting nodes, and also determines the priority of communication arbitration. The RTR (Remote Transmission Request) used in the CAN protocol is replaced with the 1-bit RRS. The ID (Identifier) ​​is used to identify data content and transmitting nodes, and also determines the priority of communication arbitration. In this embodiment, the identifier field (ID field) 610 is used as a communication arbitration field to determine whether data has been successfully received by the receiving circuit 230 of the ECU 200. In the standard format, the identifier field (ID field) 610 is 11 bits long.

[0052] The CAN FD control field consists of IDE, FDF, res, BRS, ESI, and DLC. Compared to the CAN protocol, FDF, BRS, and ESI have been added in CAN FD. IDE is the same as in the CAN protocol and is a field used to distinguish between standard format (e.g., 11 bits) and extended format (e.g., 29 bits). In standard format, a dominant signal (logical value 0) is set to IDE, and in extended format, a recessive signal (logical value 1) is set to IDE. res corresponds to a reserved bit in the CAN protocol, and DLC (Data Length Code) is a field that indicates how many bytes of data will be transmitted in the subsequent data field.

[0053] FDF (FD Format Indicator) is a field used to distinguish between the CAN protocol and the CAN FD protocol. In the CAN protocol, it is set to dominant (=0), and in the CAN FD protocol, it is set to recessive (=1).

[0054] BRS (Bit Rate Switch) is a field for switching to a faster data phase, and the transmitting node switches to a clock mode with a higher transfer speed at the BRS sampling point. When the BRS setting switches to a clock mode with a higher transfer speed, the responding receiving node also switches its clock mode in the same way.

[0055] ESI (Error State Indicator) is a data frame that indicates the error state of the sending node. In the error active state, which indicates a normal state where no errors have occurred, the dominant state is set, and when the error counter exceeds a certain value, the state transitions from error active to error passive. In the error passive state, the recessive state is set.

[0056] The DLC (Data Length Code) is a field that indicates how many bytes of data will be transmitted in the following data field. The data field is the portion of the data to be transmitted, and is the data of the length set by the DLC. All bytes in the data field are transmitted using the most significant bit (MSB). The data field in the CAN protocol is 0 to 8 bytes long (0 to 64 bits long), but the CAN FD protocol can transmit up to 64 bytes of data, and the data length can be selected from 0 to 8, 12, 16, 20, 24, 32, 48, and 64 bytes.

[0057] The CRC (Cyclic Redundancy Check) field of the CAN FD protocol consists of a Stuff Count, CRC, and CRC Delimiter (CRC_DEL).

[0058] The 4-bit Stuff Count contains the remainder (3 bits) obtained by dividing the number of stuff bits before the CRC area by 8 (Stuff bit count modulo 8) and gray-coded it, as well as the parity bit (1 bit) of the gray-coded value.

[0059] In order to maintain transmission quality as the data field increases, the CRC (Cyclic Redundancy Check) is set with the calculation result of the transmission value including not only the bits in the data field from SOF but also the Stuff Count and stuff bits. If the transmission data is 16 bytes or less, a 17-bit data field is set for the CRC, and if the transmission data is more than 16 bytes, a 21-bit data field is set for the CRC.

[0060] Like the CAN protocol, the CAN FD protocol employs a bit stuffing rule from the SOF to the end of the data field (data format). In the CRC field, fixed stuff bits are placed at the beginning of the CRC field and at fixed bit positions, and the value of the fixed stuff bit is set to the opposite value of the previous bit. For example, if the same level state occurs N times (e.g., 5 times) consecutively on the bus signal lines 31 and 32, a state bit (stuff bit) opposite to the state transmitted up to that point is inserted. CRC_DEL (CRC delimiter) is a field indicating the end of the CRC sequence. According to the bit stuffing rule, if the same level state (dominant or recessive) continues for N+1 bits (e.g., 6 bits) or more on the bus signal lines 31 and 32, it is treated as a stuff error.

[0061] The ACK (ACKnowledge) field (confirmation field) in the CAN FD protocol is composed of an ACK and an ACK Delimiter (ACK_DEL (ACK delimiter)), similar to the CAN protocol. ACK (ACKnowledge) is a confirmation field used to determine whether the data up to the transmitted CRC has been successfully received by the receiving circuit 230 of the destination node (e.g., the ECU 200 being tested). The confirmation field is 1 bit long, and the transmitting node transmits a dominant (logical value 0) and, if the receiving node has successfully received the data up to the CRC field, transmits a recessive (logical value 1) acknowledgment. ACK_DEL (ACK delimiter) is a field indicating the end of the ACK field. Following the ACK_DEL (ACK delimiter), EOF (End Of Frame) is a field transmitted at the end of the data frame.

[0062] (CAN FD extended format) The extended format shown in ST64 has a different configuration from the standard format (ST63). The base ID is 11 bits long, and the ID in the standard format is called the base ID in the extended format. In the extended format, the base ID is followed by the SRR (Substitute Remote Request Bit), which is set to a 1-bit dominant signal. Following the SRR is the IDE (Identifier Extension Bit), which is set to a 1-bit recessive signal (logical value 1).

[0063] In the extended format, the identifier field (ID field) 610 is composed of an 11-bit base ID field and an 18-bit extended ID field. That is, in the extended format, the identifier field (ID field) 610 is composed of 29 bits (= 11 bits + 18 bits).

[0064] [Inspection processing flow] Next, a description will be given of the flow of inspection processing using the inspection device 10 of this embodiment. Fig. 4 is a diagram illustrating the processing flow of inspection using the inspection device 10. The processing of each part of the functional configuration of the inspection device 10 shown in Fig. 3 will be described together with the inspection processing flow of Fig. 4.

[0065] In step S400, the operator performing the inspection uses the connection unit 30 to establish a one-to-one connection between the inspection device 10 and the communication circuit 210 of the ECU 200 to be inspected.

[0066] Next, in step S410, the inspection device 10 is powered on. Also, power is supplied to the ECU 200 to be inspected from the power supply unit 105 of the inspection device 10 or from the vehicle side. This establishes CAN communication between the inspection device 10 and the ECU 200 to be inspected.

[0067] [ECU200 transmission function inspection] In step S420, initial message check unit 110 checks whether or not there is an initial message transmitted from transmission circuit 220 of ECU 200. Here, the initial message refers to a message based on a predetermined data format that is transmitted first from ECU 200 after power is supplied to ECU 200. After power supply unit 105 supplies power to ECU 200 or after power is supplied to ECU 200 from the vehicle side, initial message check unit 110 checks whether or not there is an initial message transmitted from transmission circuit 220 of the ECU.

[0068] The transmission function determination unit 120 determines whether the transmission function of the transmission circuit 220 of the ECU 200 is normal based on the confirmation (presence or absence of an initial message) by the initial message confirmation unit 110. The transmission function determination unit 120 determines that the transmission function of the ECU 200 is in a malfunctioning state if a malfunctioning state (abnormality) continues for consecutive determination times (first consecutive determination time, second consecutive determination time). If an initial message is output from the transmission circuit 220 of the ECU 200 for a predetermined consecutive determination time, the transmission function determination unit 120 determines that the transmission circuit 220 of the ECU 200 is normal. Furthermore, if an initial message is not output from the transmission circuit 220 of the ECU 200 for a predetermined consecutive determination time, the transmission function determination unit 120 determines that the transmission circuit 220 of the ECU 200 is malfunctioning. The inspection device 10 of this embodiment can inspect the CAN communication function (transmission function) of the ECU 200 to be inspected. Note that checking for the presence or absence of an initial message differs from receiving a message in that it does not determine whether or not there is an error, as in the processes of steps S820 and S870 in Fig. 8. In this embodiment, receiving a message is processing for acquiring a message without detecting any of the CRC error, form error, and stuff error, as will be described later in step S435, and in this respect checking for the presence or absence of an initial message is distinguished from receiving a message.

[0069] Then, in step S430, the transmission function determination unit 120 displays the determination result on a display unit (not shown) of the inspection device 10. The display unit may be configured, for example, as an indicator that allows the determination result to be visually confirmed, or the determination result may be displayed using a display device such as a liquid crystal or organic electroluminescence (EL). Furthermore, instead of being limited to a visual display, for example, a speaker (sound source) (not shown) may be configured to switch between an alarm sound when a normal determination is made and an alarm sound when a malfunction is made. This allows the worker (operator) performing the inspection to visually or audibly confirm the determination result of the inspection device 10.

[0070] [ECU200 receiving function test] In order to inspect the receiving function of the ECU 200, the inspection device 10 determines the transmission speed (bit rate: S435) in CAN communication and the data format (S440) based on the message transmitted from the ECU 200. The inspection device 10 determines the bit rate and format of the message based on the message received from the transmission circuit 220 of the ECU 200 (the initial message output first, or the message transmitted after the initial message).

[0071] (Determining bit rate (receiving message)) In step S435, receiving unit 150 determines the transmission speed (bit rate) in CAN communication based on the message received from ECU 200. By performing processing to determine the transmission speed (bit rate) of the message, it is possible to receive the message from ECU 200 without error, and to accurately determine the data format in the subsequent step S440. Figure 9 is a diagram illustrating a specific flow of the processing to determine the transmission speed (bit rate).

[0072] In step S910, the receiving unit 150 sets the initial value of the bit rate to 1 Mbps.

[0073] In step S920, receiving unit 150 determines, based on the initial value setting (S910), whether or not it can receive the message from ECU 200. If the CRC calculated based on the message does not match the CRC value included in the message, receiving unit 150 determines that there is a CRC error (S920-NO), and proceeds to step S930.

[0074] Furthermore, the CRC_DEL (CRC delimiter), ACK_DEL (ACK delimiter), and EOF in a message are normally recessive (logical value 1). If a dominant (logical value 0) is detected, a form error is detected (S920-NO) and processing proceeds to step S930.

[0075] In addition, the receiving unit 150 monitors whether the bit stuffing rules are being followed, and if the same level state on the bus signal lines 31 and 32 continues for a predetermined number of bits (e.g., 6 bits) or more, it determines that a stuffing error has occurred (S920-NO) and proceeds to step S930.

[0076] If the receiving unit 150 detects at least one of a CRC error, a form error, and a stuff error, the process proceeds to step S930.

[0077] In step S930, the receiving unit 150 reduces the initial bit rate (1 Mbps → 500 Kbps) and determines whether the message can be received (S920). If the message cannot be received (S920-NO), the receiving unit 150 sequentially reduces the bit rate (500 Kbps → 250 Kbps → 125 Kbps) and determines whether the message can be received (S920).

[0078] If the receiving unit 150 detects no error among the CRC error, form error, and stuff error, it determines that the message has been received successfully (S920-YES), and the process proceeds to step S940.

[0079] In step S940, the receiving unit 150 determines the bit rate at which the message can be received without errors. For example, if the message can be received without detecting any of the CRC error, form error, and stuff error at a setting of 250 Kbps, the receiving unit 150 determines the bit rate of the message to be 250 Kbps.

[0080] Next, in step S950, receiving unit 150 determines whether the value of FDF in the message format is 1. If the value of FDF is not 1 (S950-NO), the process returns to step S435. In this case, the transmission speed (bit rate) in the CAN protocol becomes the value determined in step S940. On the other hand, if it is determined in step S950 that FDF=1 (S950-YES), the process proceeds to step S960.

[0081] Then, in step S960, the receiving unit 150 sets 1 Mbps as the initial value of the bit rate of the CAN FD protocol.

[0082] In step S970, receiving unit 150 determines, based on the initial value setting (S960), whether or not it can receive a message from ECU 200. Receiving unit 150 determines whether or not an error has occurred, similar to the determination process in step S920. In step S970, if receiving unit 150 detects at least one error from among a CRC error, a form error, and a stuff error, it proceeds to step S980.

[0083] In step S980, receiving unit 150 increases the bit rate from the initial value (1 Mbps → 2 Mbps) and determines whether the message can be received (S970). If the message cannot be received (S970-NO), receiving unit 150 increases the bit rate value successively (2 Mbps → 4 Mbps → 5 Mbps → 8 Mbps) and determines whether the message can be received (S970).

[0084] If the receiving unit 150 detects no error among the CRC error, form error, and stuff error, it determines that the message has been received successfully (S970-YES), and the process proceeds to step S990.

[0085] In step S990, the receiving unit 150 determines the bit rate at which the message could be received without errors. For example, if the message could be received at 8 Mbps without detecting any of the CRC errors, form errors, and stuff errors, the receiving unit 150 determines the bit rate of the message to be 8 Mbps. After step S990, the process returns to step S435. In this case, the transmission speed (bit rate) in the CAN FD protocol becomes the value determined in step S990. This completes the process of determining the transmission speed (bit rate).

[0086] (Data format determination) In step S440, receiving unit 150 determines the data format of the message transmitted from ECU 200. Fig. 10 is a diagram illustrating a specific flow of the data format determination process.

[0087] In step S435, the receiving unit 150 determines the bit rate. This process is the process previously described with reference to Fig. 9, and the receiving unit 150 acquires the transmission speed (bit rate) of the transmitted message based on the process of step S435.

[0088] In step S1010, the receiving unit 150 determines whether the signal set in the IDE of the message is dominant. If the signal set in the IDE is dominant (IDE=0) (S1010-True), the receiving unit 150 proceeds to S1020.

[0089] In step S1020, the receiving unit 150 determines whether the signal set in the FDF of the message is dominant. If the signal set in the FDF is dominant (FDF=0) (S1020-True), the receiving unit 150 proceeds to S1040.

[0090] Then, in step S1040, the receiving unit 150 determines that the format of the received message is the standard format of the CAN protocol (11-bit CAN).

[0091] On the other hand, if it is determined in step S1020 that the signal set in FDF is recessive (FDF=1) (S1020-False), receiving unit 150 advances the process to S1050.

[0092] Then, in step S1050, receiving unit 150 determines that the format of the received message is the standard format of the CAN FD protocol (11-bit CAN FD).

[0093] On the other hand, if it is determined in step S1010 that the signal set in IDE is recessive (IDE=1) (S1010-False), the receiving unit 150 advances the process to S1030.

[0094] In step S1030, the receiving unit 150 determines whether the signal set in the FDF of the message is dominant. If the signal set in the FDF is dominant (FDF=0) (S1030-True), the receiving unit 150 proceeds to S1060.

[0095] Then, in step S1060, the receiving unit 150 determines that the format of the received message is the extended format (29-bit CAN) of the CAN protocol.

[0096] On the other hand, if it is determined in step S1030 that the signal set in the FDF is recessive (FDF=1) (S1030-False), the receiving unit 150 advances the process to S1070.

[0097] Then, in step S1070, the receiving unit 150 determines that the format of the received message is the extended format (29-bit CAN FD) of the CAN FD protocol. This completes the format determination process.

[0098] (Generates inspection message 600) In step S450, based on the determination result of the transmission speed (bit rate) (S435) and the determination result of the data format (S440), the inspection message creation unit 130 generates an inspection message 600 corresponding to the communication protocol of the inspection target ECU 200. By processing this step, the inspection message creation unit 130 creates the inspection message 600 in which a predetermined signal level indicating a higher priority in communication arbitration than the message received from the inspection target ECU 200 is set in the identifier field 610 of the data format corresponding to the message received from the inspection target ECU 200.

[0099] The inspection message creation unit 130 of the inspection device 10 generates an inspection message 600 (FIGS. 6A and 6B) by setting a predetermined signal level in the identifier field 610 of the inspection message 600 (FIG. 6A, FIG. 6B) to indicate a higher priority in communication arbitration than the message transmitted from the ECU 200. The receiving function determination unit 170 of the inspection device 10 then determines the receiving function of the ECU 200 based on whether message transmission from the ECU 200 stops after the transmission of the inspection message 600. FIG. 5 is a diagram schematically illustrating the flow of receiving a message transmitted from the ECU 200 (determining the bit rate: S435), determining the data format of the message (S440), and generating the inspection message 600 (S450).

[0100] There are a wide variety of data formats for messages in CAN communication, but the inspection device 10 of this embodiment stores a different data format for each ECU to be inspected, and can automatically determine the data format.Based on the results of the transmission speed (bit rate) determination (S435) and the data format determination (S440), an inspection message corresponding to the communication protocol of the ECU 200 to be inspected can be created.

[0101] This reduces the burden on the operator who performs the inspection and enables the inspection to be completed in a shorter time than if the operator prepared the specifications of the ECU 200 to be inspected in accordance with the inspection.

[0102] To perform the data format determination process, the check message creation unit 130 of this embodiment includes a storage unit 133 and a selection unit 135 (FIG. 3). The storage unit 133 stores data formats classified based on a combination of a plurality of communication protocol types, frame rates, and transmission speeds, and the selection unit 135 selects, from the storage unit 133, a data format that corresponds to the message received from the transmission circuit 220 of the ECU 200. The storage unit 133 is, for example, a recording medium that can non-volatilely store various data formats, and is realized by, for example, a hard disk drive, a flash memory, or the like.

[0103] The storage unit 133 stores data formats classified based on a combination of, for example, the type of communication protocol (e.g., CAN, CAN FD, etc.), frame rate (e.g., 11 bit, 29 bit, etc.), and transmission speed (e.g., CAN: 125 Kbps, 250 Kbps, 500 Kbps, 1 Mbps; CAN FD: 1 Mbps, 2 Mbps, 4 Mbps, 5 Mbps, 8 Mbps, etc.). Note that the classification example of the data formats is merely illustrative and is not limited to this example.

[0104] The inspection message creation unit 130 creates an inspection message 600 (FIGS. 6A and 6B) based on the data format selected by the selection unit 135. For example, if the selection unit 135 selects a data format with a communication protocol type (CAN FD), a frame rate (29 bits), and a transmission speed (8 Mbps) from the storage unit 133, the inspection message creation unit 130 creates an inspection message based on the data format selected by the selection unit 135.

[0105] In this step, the inspection message creation unit 130 uses a data format automatic discrimination function to generate an inspection message 600 corresponding to the data format of each ECU 200 to be inspected. In order to determine whether the inspection message 600 has been successfully received by the receiving circuit 230 of the ECU 200, the inspection message creation unit 130 creates the inspection message 600 by setting a predetermined signal level in the data format identifier field (ID field) 610, which indicates a higher priority in communication arbitration than the message transmitted from the ECU 200.

[0106] 8 is a diagram showing a setting example of the identifier field (ID field) 610. Setting example 810 shows a setting example of the identifier field (ID field) 610 set by the inspection message creation unit 130, and setting example 820 shows a setting example of the identifier field (ID field) set by the ECU 200. CAN data 830 shows CAN data indicating the signal level (bus state) of the bus communication lines (31, 32).

[0107] In this embodiment, the test message creation unit 130 creates a test message 600 in which, for example, a logical value of 0 (dominant level) is set in the identifier field 610 as a predetermined signal level indicating a high priority of communication arbitration. The identifier field 610 is configured with 11 bits in the standard data format, for example. Note that the setting example in FIG. 8 is not limited thereto, and the number of bits in the identifier field 610 can also be adjusted to 29 bits in the extended format according to the CAN standard.

[0108] In a setting example 810 on the inspection device 10 side, a dominant level (logical value 0) is set as the signal level from the 10th bit to the 4th bit, and a recessive level (logical value 1) is set as the signal level from the 3rd bit to the 0th bit. The setting in the identifier field 610 is arbitrary, and the inspection message creation unit 130 may set a dominant level (logical value 0) as the signal level from the 3rd bit to the 0th bit, not limited to the setting example 810 of FIG. 8. In the transmission signals of the bus signal lines 31 and 32, a dominant level is a signal with a higher priority than a recessive level. Setting all bits of the identifier field 610 to the dominant level (logical value 0) results in the signal level with the highest priority.

[0109] In the setting example 820 on the ECU 200 side in FIG. 8, the signal levels from the 10th bit to the 4th bit are set to a dominant level (logical value 0), and the signal levels from the 3rd bit to the 0th bit are set to a recessive level (logical value 1).

[0110] (Send inspection message 600) Then, in step S460, the transmitter 140 transmits the inspection message 600 created by the inspection message creator 130 to the receiver circuit 230 of the ECU 200. The transmitter 140 transmits the inspection message 600 to the ECU 200 at the transmission rate determined in S435. Fig. 7 is a diagram schematically showing the flow from transmitting the inspection message 600 (S460), checking whether or not there is a message to be transmitted from the ECU 200 (S470), to determining the receiving function (S480).

[0111] (Example of setting identifier fields and message collision reconciliation) The rules of the CAN communication protocol stipulate that when messages are sent from multiple communication nodes (ECUs), arbitration should be performed according to the setting of the identifier (ID) field. Using a mechanism that stops message transmission while a message with a high-priority identifier (ID) field is being received, the inspection device 10 of this embodiment transmits a message with a high-priority identifier (ID) field to the ECU 200 under inspection, thereby determining whether the receiving function of the ECU 200 is normal.

[0112] 8, when messages are transmitted simultaneously from the inspection device 10 and the ECU 200, the signal in the SOF field at the beginning of the message is transmitted, but the signals in both SOF fields are set to a dominant level (logical value 0), and the CAN data 830 is at a dominant level (logical value 0). The inspection device 10 and the ECU 200 compare the signal in the SOF field transmitted by themselves with the CAN data 830, and since the signal in the SOF field and the signal in the CAN data 830 are identical, the inspection device 10 and the ECU 200 continue transmission.

[0113] Next, the data in the identifier field is transmitted bit by bit. If the signal levels of the transmitted bits are the same, that is, if the test device 10 and the ECU 200 transmit signals at a dominant level (logical value 0), the CAN data 830 remains at the dominant level (logical value 0). In the example of Fig. 8, the signal levels of the test device 10 and the ECU 200 are the same from the 10th bit to the 5th bit.

[0114] On the other hand, if a recessive level signal and a dominant level signal are transmitted simultaneously, for example, as in the fourth bit of Fig. 8, the dominant level (logical value 0) on the inspection device 10 side takes priority, and the CAN data 830 becomes the dominant level. In this case, the ECU 200 that transmitted the recessive level (logical value 1) detects that it has lost the communication arbitration due to the difference between the signal (logical value 1) of the identifier field 610 that it transmitted and the CAN data 830 (logical value 0), and stops transmitting the message.

[0115] The inspection device 10 side continues to transmit the third bit and subsequent bits of the identifier field 610, but the ECU 200 side stops transmitting the message signal from the third bit onward.

[0116] While receiving the inspection message 600 with a high-priority identifier field, if the receiving function of the receiving circuit 230 is operating normally, the ECU 200 maintains the state of stopping message transmission. On the other hand, if a malfunction occurs in the receiving function of the receiving circuit 230, the ECU 200 starts transmitting a message corresponding to the inspection message 600 transmitted from the inspection device 10. Alternatively, if a malfunction occurs in the receiving function of the receiving circuit 230, the ECU 200 continues transmitting messages.

[0117] (Check for messages) The receiving unit 150 of the inspection device 10 of this embodiment is configured to be able to receive messages transmitted from the ECU 200, and in step S470, after transmitting the inspection message 600, the receiving unit 150 checks whether or not there is a message from the transmitting circuit 220 of the ECU 200.

[0118] (Receiving function determination process) In step S480, receiving function determination unit 170 determines whether the receiving function of ECU 200 is normal based on whether receiving unit 150 receives a message after transmitting test message 600. In this step, if receiving function determination unit 170 receives a message from ECU 200 during the first continuous determination time or the second continuous determination time, receiving function determination unit 170 determines that the communication function (receiving function) of ECU 200 is malfunctioning. Furthermore, if receiving function determination unit 170 does not receive a message from ECU 200 during the first continuous determination time or the second continuous determination time, receiving function determination unit 170 determines that the communication function (receiving function) of ECU 200 is normal.

[0119] According to the rules of the CAN communication protocol, if the receiving function in the receiving circuit 230 of the ECU 200 is normal, while the receiving circuit 230 is receiving the inspection message 600 with the high priority identifier field, the ECU 200 stops sending messages, maintains the stopped state, and shifts the sending timing of the conflicting messages to transmit them at the available timing.

[0120] If message transmission from ECU 200 is stopped after transmission of the check message 600, the receiving function determination unit 170 determines that the receiving function of ECU 200 (receiving circuit 230) is normal. On the other hand, if a malfunction occurs in the receiving function of ECU 200 (receiving circuit 230), message transmission from ECU 200 continues even after transmission of the check message 600, and the receiving unit 150 receives messages from ECU 200. In this case, the receiving function determination unit 170 determines that the receiving function of ECU 200 (receiving circuit 230) is malfunctioning. If the receiving function determination unit 170 receives a message from ECU 200 during the first continuous determination time or the second continuous determination time set by the determination time change unit 180, the receiving function determination unit 170 determines that the receiving function of ECU 200 is malfunctioning.

[0121] In step S490, the receiving function determination unit 170 displays the determination result on a display unit (not shown) of the inspection device 10. The display of the determination result is the same as in step S430. With the above processing, the series of inspection flows by the inspection device 10 ends.

[0122] (Summary of the embodiment) The above embodiment discloses at least the following inspection device (10) and inspection method.

[0123] Configuration 1. The inspection device of the above embodiment is an inspection device (10) that inspects the CAN communication function of the ECU (200) to be inspected, a connection unit (30) for connecting the communication circuit of the ECU and the inspection device one-to-one; a test message creation unit (130) that creates a test message in which a predetermined signal level indicating a higher priority in communication arbitration than a message received from an ECU to be tested is set in an identifier field of a data format corresponding to the message; a transmitting unit (140) that transmits the inspection message to the ECU; a receiving unit (150) that receives a message transmitted from the ECU; a receiving function determination unit (170) that determines whether a receiving function of the ECU is normal or not based on whether the receiving unit receives a message from the ECU after the transmission of the inspection message; An inspection device comprising:

[0124] The inspection device of configuration 1 can inspect the CAN communication function (receiving function) of the ECU under inspection. This makes it possible to inspect the CAN communication function (receiving function) of the ECU under inspection without inspecting by replacing a non-defective device, thereby reducing the cost of preparing a non-defective device for inspection and the number of steps required for replacing the device during inspection work.

[0125] Configuration 2. The inspection device of the above embodiment includes a power supply unit (105) that supplies power to the ECU; an initial message confirmation unit (110) of the ECU that confirms whether or not an initial message transmitted from the ECU exists; a transmission function determination unit (120) that determines whether a transmission function of the ECU is normal or not by checking whether the initial message is present or absent by the initial message check unit, The initial message confirmation unit (120) confirms whether or not the initial message transmitted from the ECU exists after the power supply unit supplies the power to the ECU or after the vehicle supplies power to the ECU.

[0126] The inspection device of configuration 2 can inspect the CAN communication function (transmission function) of the ECU under inspection. This makes it possible to inspect the CAN communication function (transmission function) of the ECU under inspection without inspecting by replacing a non-defective device, reducing the cost of preparing a non-defective device for inspection and the number of steps required for replacing the device during inspection work.

[0127] Configuration 3. The inspection message creation unit (130) a storage unit (133) that stores data formats classified based on a combination of a type of communication protocol, a frame rate, and a transmission speed; a selection unit (135) that selects, from the storage unit, a data format corresponding to the message received from the ECU; The inspection message creation unit (130) creates the inspection message based on the data format selected by the selection unit.

[0128] The inspection device of configuration 3 can automatically determine the data format of a message received from an ECU, and based on the determination result, create an inspection message in a data format corresponding to the message received from the ECU. This reduces the burden on the operator performing the inspection and enables the inspection to be completed in a shorter time than if the operator had to prepare the specifications of the ECU to be inspected in accordance with the inspection.

[0129] Configuration 4. The inspection device (10) of the above embodiment further includes a judgment time change unit (180) that changes the continuous judgment time for determining whether the CAN communication function is normal or not from a first continuous judgment time to a second continuous judgment time that is shorter than the first continuous judgment time, based on input from the sensitivity switching means.

[0130] Configuration 5. The receiving function determination unit (170) determines whether the receiving function of the ECU is normal or not based on the first continuous determination time, When the determination time is changed by the determination time change unit, the receiving function determination unit determines whether or not the receiving function of the ECU is normal based on the second continuous determination time.

[0131] Configuration 6. The receiving function determination unit (170) determines that the receiving function of the ECU is malfunctioning when a message is received from the ECU during the first continuous determination time or the second continuous determination time, If no message is received from the ECU during the first continuous determination time or the second continuous determination time, it is determined that the receiving function of the ECU is normal.

[0132] According to the inspection devices of the configurations 4, 5 and 6, it is possible to detect consecutive abnormalities in a short sampling time even for an ECU in an operating state where a failure state is unlikely to occur consecutively.

[0133] Configuration 7. The inspection method of the above embodiment is a method for inspecting an inspection device that is connected one-to-one to a communication circuit of an ECU to be inspected via a connection unit and inspects the CAN communication function of the ECU to be inspected, a step (S450) in which an inspection message creation unit (130) of the inspection device creates an inspection message in which a predetermined signal level indicating a higher priority of communication arbitration than the message is set in an identifier field of a data format corresponding to the message received from the ECU to be inspected; a step (S460) in which a transmitting unit (140) of the inspection device transmits the inspection message to the ECU; a receiving step (S470) in which a receiving unit (150) of the inspection device receives a message transmitted from the ECU; The receiving function determination unit (170) of the inspection device has a step (S480) of determining whether the receiving function of the ECU is normal or not based on whether a message is received from the ECU in the receiving step after sending the inspection message.

[0134] According to the inspection method of configuration 7, it is possible to inspect the CAN communication function (reception function) of the ECU to be inspected. This makes it possible to inspect the CAN communication function (reception function) of the ECU to be inspected without inspecting by replacing a non-defective device, thereby reducing the cost of preparing a non-defective device for inspection and the number of steps required for replacing the device during the inspection work.

[0135] (Other embodiments) The present invention also makes it possible to supply a program that realizes the functions of the above-described embodiments to a system or an inspection device that constitutes the system via a network or a storage medium, and have one or more processors in the computer of the inspection device read the program and execute the processing of the inspection device.

[0136] The invention is not limited to the above-described embodiment, and various modifications and variations are possible within the scope of the gist of the invention. [Explanation of symbols]

[0137] 10: Inspection device, 20: ECU to be inspected, 30: Connection part, 110: initial message confirmation unit, 120: transmission function determination unit, 130: inspection message creation unit, 140: transmission unit, 150: reception unit 170: Receiving function determination unit, 180: Determination time change unit

Claims

1. An inspection device that inspects a CAN communication function of an ECU to be inspected, a connection unit that connects a communication circuit of the ECU and the inspection device one-to-one; a test message generator that generates a test message in which a predetermined signal level indicating a higher priority in communication arbitration than a message received from an ECU to be tested is set in an identifier field of a data format corresponding to the message; a transmitting unit that transmits the inspection message to the ECU; a receiving unit that receives a message transmitted from the ECU; a receiving function determination unit that determines whether a receiving function of the ECU is normal or not based on whether the receiving unit receives a message from the ECU after the transmission of the check message; a judgment time changing unit that changes a continuous judgment time for determining whether the CAN communication function is normal or not from a first continuous judgment time to a second continuous judgment time that is shorter than the first continuous judgment time, in response to an input from a sensitivity switching unit; An inspection device comprising:

2. a power supply unit that supplies power to the ECU; an initial message confirmation unit of the ECU that confirms whether or not an initial message is transmitted from the ECU; a transmission function determination unit that determines whether a transmission function of the ECU is normal or not by checking whether the initial message is present or absent by the initial message check unit, The initial message check unit checks whether or not the initial message is transmitted from the ECU after the power supply unit supplies the power to the ECU or after the vehicle supplies the power to the ECU.

2. The inspection device according to claim 1.

3. The inspection message creation unit a storage unit that stores data formats classified based on a combination of a type of communication protocol, a frame rate, and a transmission speed; a selection unit that selects, from the storage unit, a data format corresponding to the message received from the ECU, The inspection message creation unit creates the inspection message based on the data format selected by the selection unit.

3. The inspection device according to claim 2.

4. the reception function determination unit determines whether the reception function of the ECU is normal based on the first continuous determination time, When the determination time is changed by the determination time change unit, the receiving function determination unit determines whether the receiving function of the ECU is normal or not based on the second continuous determination time.

2. The inspection device according to claim 1.

5. the reception function determination unit determines that the reception function of the ECU is malfunctioning when a message is received from the ECU during the first continuous determination time or the second continuous determination time; 5. The inspection device according to claim 1, wherein the receiving function of the ECU is determined to be normal if no message is received from the ECU during the first continuous determination time or the second continuous determination time.

6. A testing method for a testing device that connects one-to-one with a communication circuit of an ECU to be tested via a connection unit and tests a CAN communication function of the ECU to be tested, comprising: a step in which an inspection message creation unit of the inspection device creates an inspection message in which a predetermined signal level indicating a higher priority in communication arbitration than the message is set in an identifier field of a data format corresponding to the message received from the ECU to be inspected; a transmitting unit of the inspection device transmitting the inspection message to the ECU; a receiving step in which a receiving unit of the inspection device receives a message transmitted from the ECU; a step in which a receiving function determination unit of the inspection device determines whether or not a receiving function of the ECU is normal based on whether or not a message is received from the ECU in the receiving step after transmitting the inspection message; a step in which a judgment time changing unit of the inspection device changes a continuous judgment time for determining whether the CAN communication function is normal or not from a first continuous judgment time to a second continuous judgment time that is shorter than the first continuous judgment time, based on an input from a sensitivity switching means; An inspection method comprising:

Images