Inspection apparatus and inspection method
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HONDA MOTOR CO LTD
- Filing Date
- 2022-12-20
- Publication Date
- 2026-06-16
Smart Images
Figure CN116471140B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to an inspection apparatus and an inspection method. Background Technology
[0002] Previously, vehicles were equipped with multiple electronic devices to perform various processes. To control the operation of these electronic devices, vehicles were equipped with multiple ECUs (Electronic Control Units). To enable the multiple ECUs to coordinate their operations, they were interconnected via a network to send and receive data, thereby sharing information. CAN (Controller Area Network) was widely used as the communication protocol for this purpose.
[0003] Patent document 1 discloses a communication system in which multiple ECUs are interconnected via a common communication line. A message sent by one ECU is received by multiple other ECUs, and reception success or failure information indicating the success or failure of message reception is generated and sent.
[0004] Existing technical documents
[0005] Patent documents
[0006] Patent Document 1: Japanese Patent No. 5717240 Specification Summary of the Invention
[0007] The problem that the invention aims to solve
[0008] Since it is impossible to perform internal inspections on the IPU (Integrated Power Unit), DU (Drive Unit), CHGR (Charger) and other components that make up an electric vehicle, we replace normally functioning good equipment one by one to identify the equipment that is malfunctioning. We then conduct inspections by replacing the good equipment to confirm whether the inspection information has improved.
[0009] However, during the inspection for replacing defective products, expensive equipment needs to be prepared for the inspection, and the equipment replacement work also requires a set amount of time.
[0010] On the other hand, in the communication system of Patent Document 1, one ECU receives success or failure information, thereby confirming that the local unit can correctly send messages to any other ECU. However, it cannot determine whether the CAN communication function (receiving function) of the message's destination, i.e., the other ECU, is functioning properly.
[0011] In view of the above-mentioned problems, the present invention aims to provide an inspection technique capable of inspecting the CAN communication function in the ECU of the object to be inspected.
[0012] Solution for solving the problem
[0013] One aspect of the present invention relates to an inspection apparatus for inspecting the CAN communication function of an ECU (Electronic Control Unit) of an inspection target. The inspection apparatus includes: a connection unit that connects the communication circuit of the ECU to the inspection apparatus one-to-one; an inspection message generation unit that generates an inspection message by setting a predetermined signal level in an acknowledgment field of a data format corresponding to a message received from the ECU of the inspection target; a sending unit that sends the inspection message to the ECU; a receiving unit that receives a response message from the ECU in response to the inspection message; an acknowledgment unit that confirms whether the signal level of the acknowledgment field in the response message has changed relative to the setting of the inspection message; and a reception function determination unit that determines whether the reception function of the ECU is normal based on the confirmation of the acknowledgment unit.
[0014] Other aspects of the present invention relate to an inspection method using an inspection apparatus connected one-to-one with the communication circuit of an ECU to be inspected via a connection unit, and inspecting the CAN communication function of the ECU. This inspection method includes: a step whereby the inspection device's inspection message generation unit generates an inspection message with a predetermined signal level set in an acknowledgment field corresponding to a message received from the ECU to be inspected; a step whereby the inspection device's sending unit sends the inspection message to the ECU; a step whereby the inspection device's receiving unit receives a response message from the ECU in response to the inspection message; a confirmation step whereby the inspection device's confirmation unit confirms whether the signal level of the acknowledgment field in the response message has changed relative to the setting of the inspection message; and a step whereby the inspection device's receiving function determination unit determines whether the ECU's receiving function is normal based on the confirmation result of the confirmation step.
[0015] The effects of the invention
[0016] According to the present invention, an inspection technique is provided that can inspect the CAN communication function in the ECU of the object being inspected. Attached Figure Description
[0017] Figure 1 This is a diagram showing the outline structure of an inspection system including an inspection apparatus according to an embodiment.
[0018] Figure 2 This is a diagram showing an example of the circuit structure of the ECU being inspected.
[0019] Figure 3 This is a diagram illustrating the functional structure of the inspection device according to the embodiment.
[0020] Figure 4 This is a diagram illustrating the process of performing an inspection using the inspection device described in the embodiment.
[0021] Figure 5 It is a diagram that schematically illustrates the process of receiving a message, determining the data format of the message, and finally checking the generation and sending of the message.
[0022] Figure 6A This is a diagram illustrating an example of the data format structure of an inspection message based on the CAN protocol.
[0023] Figure 6B This is a diagram illustrating an example of the data format structure of an inspection message based on the CAN FD protocol.
[0024] Figure 7 It is a schematic diagram illustrating the process of receiving a response message, confirming the signal level of the acknowledgment field, and finally determining the reception function.
[0025] Figure 8 This is a diagram illustrating the process of determining bit rate.
[0026] Figure 9 This is a diagram illustrating the process of data format identification and processing.
[0027] Explanation of reference numerals in the attached figures
[0028] 10: Inspection device; 20: ECU of the object to be inspected; 30: Connection unit; 110: Initial message confirmation unit; 120: Transmission function determination unit; 130: Inspection message generation unit; 140: Transmission unit; 150: Receiving unit; 160: Confirmation unit; 170: Receiving function determination unit; 180: Determination time change unit. Detailed Implementation
[0029] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Furthermore, the following embodiments are not intended to limit the scope of the claims, and the present invention does not require a combination of all the features described in the embodiments. Two or more features from the plurality of features described in the embodiments may be arbitrarily combined. Additionally, the same or identical structures are labeled with the same reference numerals, and repeated descriptions are omitted.
[0030] [Overview structure of the inspection system including inspection device 10]
[0031] Figure 1 This is a diagram showing the outline structure of an inspection system including the inspection device 10 according to the embodiments. Figure 1The example shown is an ECU 200, the ECU included in device 20, which is the object of inspection. Device 20 may also be an IPU (Integrated Power Unit), DU (Drive Unit), or CHGR (Charger), etc. The inspection device 10 of this embodiment is an inspection device for inspecting 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.
[0032] When devices such as IPU and DU are connected to the CAN bus in the vehicle, the ECU of each device 20 functions as a communication node. However, here, the connector used to connect to the CAN bus is removed, and the inspection device 10 is connected one-to-one with the ECU 200 (communication circuit 210) to be inspected. The CAN communication function in the ECU 200 to be inspected is checked by confirming the signals (messages) from the ECU 200 to be inspected.
[0033] The connection section 30 connects the inspection device 10 (CAN communication section 100) to the ECU 200 (communication circuit 210) being inspected one-to-one via the connector 34. The connection section 30 has CANL 31 and CA NH 32 as bus signal lines for CAN communication.
[0034] The power supply unit 105 can convert an external power source into a predetermined voltage (e.g., 12V) called power supply voltage VCC, and supply it to the ECU 200 under inspection via power line 33. The connection unit 30 may also include bus signal lines 31 and 32 and power line 33. Furthermore, the power supply voltage VCC is not limited to being supplied from the power supply unit 105; it can also be supplied from the vehicle side to the ECU 200 under inspection. When the power supply voltage VCC is supplied from the vehicle side, power line 33 is not required, and the connection unit 30 can be configured to include at least bus signal lines 31 and 32.
[0035] [ECU 200 being inspected]
[0036] Figure 2 This diagram illustrates an example of the circuit structure of the ECU 200 to be inspected. The ECU 200 includes a communication circuit 210 and a controller 240. The communication circuit 210 includes a transmitting circuit 220 that processes messages based on signals output from the ECU 200, and a receiving circuit 230 that processes signals (messages) received from an external source. The controller 240 is a control unit that oversees the operation of the transmitting circuit 220 and the receiving circuit 230 within the communication circuit 210.
[0037] The bus signal line 31 (CANL) of the connection section 30 is a low-potential signal line, and the bus signal line 32 (CANH) is a high-potential signal line compared to the bus signal line 31. The potential is a potential obtained by using the ground potential (i.e., ground potential) in the inspection device 10 as a reference.
[0038] The controller 240 inputs a transmit signal TXD to the transmit circuit 220, and the transmit circuit 220 outputs a signal (message) based on the transmit signal TXD, which includes a high level or a low level signal. Additionally, the receive circuit 230 converts the signal (message) received from bus signal lines 31 and 32, which includes a high level or a low level signal, into a receive signal RXD, and outputs the converted receive signal RXD to the controller 240.
[0039] In the signal levels, a high level corresponds to a data value, for example, logic 1, and as the potential of the bus signal line, it corresponds to the recessive level (CANH: 32). Conversely, a low level corresponds to a data value, for example, logic 0, and as the potential of the bus signal line, it corresponds to the dominant level (CANL: 31). Dominant means a signal with higher priority among the transmitted signals on bus signal lines 31 and 32, while recessive means a signal with lower priority among the transmitted signals on bus signal lines 31 and 32. Furthermore, the specific signal processing within the ECU 200 is known technology and will not be described in detail here.
[0040] [Inspection device 10]
[0041] (Functional Structure)
[0042] Figure 3 This diagram illustrates the functional structure of the inspection device 10 according to this embodiment. The inspection device 10 has an initial message confirmation unit 110, a transmission function determination unit 120, an inspection message generation unit 130, a transmission unit 140, a receiving unit 150, a confirmation unit 160, a receiving function determination unit 170, and a determination time change unit 180 as its functional structure.
[0043] These functional structures are implemented by reading a predetermined computer program stored in the storage medium of the inspection device 10 into RAM, and by having the CPU of the inspection device 10 perform signal processing. Alternatively, if the same function can be achieved, these functional structures can also be constructed using integrated circuits or the like.
[0044] (Sensitivity switching function settings)
[0045] The inspection device 10 of this embodiment can switch the inspection judgment time between standard mode and sensitive mode using a sensitivity switching switch (not shown).
[0046] The first continuous determination time in standard mode (e.g., 1.5 seconds) is set for abnormal detection conditions of vehicles that meet the standards. However, in reality, some malfunctions may be difficult to reproduce within the inspection time limited to the repair site. For example, in unstable conditions such as solder pad peeling, the malfunction will not occur continuously. In the time setting of standard mode, there may be situations where it is difficult to detect the continuation of malfunctioning conditions (abnormalities).
[0047] For ECUs whose malfunctions are difficult to occur continuously, the inspection device 10 of this embodiment is provided with a sensitive mode in order to easily detect continuous malfunctions. In this sensitive mode, inspection can be performed with a shorter second continuous determination time (e.g., 0.75 seconds) compared to the sampling time of the signal in the first continuous determination time.
[0048] Based on the input from the sensitivity switching switch, the determination time change unit 180 changes the continuous determination time used to determine whether the CAN communication function is normal from the first continuous determination time in the standard mode (e.g., 1.5 seconds) to the second continuous determination time in the sensitive mode (e.g., 0.75 seconds), which is shorter than the first continuous determination time.
[0049] When set to standard mode, the receiving function determination unit 170 determines whether the receiving function of the ECU 200 (receiving circuit 230) is normal based on a first continuous determination time. Furthermore, when the determination time change unit 180 changes the determination time, i.e., when set to sensitive mode, the receiving function determination unit 170 determines whether the receiving function of the ECU 200 is normal based on a second continuous determination time.
[0050] If the malfunction continues during the continuous determination time (first continuous determination time, second continuous determination time), the receiving function determination unit 170 determines that the receiving function of the ECU 200 is in a malfunctioning state.
[0051] Furthermore, the switching between standard mode and sensitive mode is also applied to the determination of the transmission function. That is, when set to standard mode, the transmission function determination unit 120 determines whether the transmission function of the ECU 200 (transmission circuit 220) is normal based on a first continuous determination time. Conversely, when the determination time change unit 180 changes the determination time, i.e., when set to sensitive mode, the transmission function determination unit 120 determines whether the transmission function of the ECU 200 is normal based on a second continuous determination time. If the malfunction (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 malfunctioning.
[0052] Furthermore, the sensitivity can be switched at any time by operating the sensitivity switching switch. For example, if the sensitivity is switched by operating the sensitivity switching switch at the beginning of the inspection or during the inspection, the determination time change unit 180 can change the determination time setting from the first continuous determination time to the second continuous determination time. Alternatively, the determination time change unit 180 can change the determination time setting from the second continuous determination time to the first continuous determination time.
[0053] [Check message data format]
[0054] Next, the structure of the data format of the inspection message generated by the inspection message generation unit 130 will be explained. The following description is an overview of the data format based on the CAN or CAN FD communication protocol, and the data format will also be referred to as a data frame. Furthermore, in the data format (data frame), the area defined by the data in bit units is called a field. Figure 6A as well as Figure 6B The data format (data frame) described herein is the data format used when the inspection message 600 is sent from the inspection device 10 to the ECU 200.
[0055] Figure 6A This diagram illustrates an example of the structure of the data format (data frame) of the inspection message 600 generated by the inspection message generation unit 130 based on the CAN protocol. Additionally, Figure 6B This diagram illustrates an example of the structure of the data format (data frame) of the inspection message generated by the inspection message generation unit 130 based on the CAN FD protocol. Figure 6A as well as Figure 6B In this context, the numerical values of each part of each data format represent the length (bit length) of the data to be used, which is equivalent to several bits.
[0056] (CAN standard format)
[0057] exist Figure 6A In the diagram, ST61 shows a standard format data frame based on the CAN protocol, and ST62 shows an extended format data frame based on the CAN protocol. ST62 partially illustrates the structure from the SOF up to the data field; the structure after the data field in ST62 is the same as the standard format in ST61.
[0058] exist Figure 6AIn ST61 and ST62, the upper line represents the recessive level (logic value 1) signal level, and the lower line represents the dominant level (logic value 0) signal level. Data with a line only on the dominant level side represents dominant data, and data with a line only on the recessive level side represents recessive data. Data with lines on both sides represents data that changes (inverts) to dominant or recessive depending on the transmitted data.
[0059] SOF (Start Of Frame) is a field that indicates the start of data frame transmission. The SOF signal level changes from a recessive level (logic value 1) during bus idle to a dominant level (logic value 0), thereby enabling the ECU 200 being checked to synchronize its reception processing.
[0060] In addition to identifying data content and the sending node, the ID (identifier) can also be used to determine the priority of communication arbitration. In the standard format, the identifier field (ID field) is 11 bits long.
[0061] The Remote Transmission Request (RTR) field is used to distinguish between data frames and remote frames. Here, the remote frame is the field used according to the requirements of the data frame. Similar to the identifier field (ID field), the RTR can be used for communication arbitration.
[0062] The IDE is a field used to distinguish between standard format (e.g., 11-bit) and extended format (e.g., 29-bit). In the standard format, dominant signals (logic value 0) are set in the IDE, while in the extended format, recessive signals (logic value 1) are set in the IDE.
[0063] "r" represents the reservation bit, and DLC (Data Length Code) is a field that indicates how many bytes of data will be sent in the subsequent data fields. The IDE, reservation bit ("r"), and DLC together are referred to as the control fields.
[0064] The data field is the portion of the data to be sent and is based on the data length set by the DLC. Within the data field, full bytes are sent starting from the most significant bit (MSB). The data field is 0 to 8 bytes long (0 to 64 bits long), and its length can be set in 1-byte increments.
[0065] CRC (Cyclic Redundancy Check) is a field that represents the result of a calculation on the sent values of the SOF, ID, control field, and data field. For example, the sending node performs the calculation on the sent value and sets the resulting value in the CRC. The receiving node, in the same way as the sending node, performs the calculation on the received values of the SOF, ID, control field, and data field and compares them with the CRC setting value, thereby determining whether the received message (data) was received correctly.
[0066] For example, when the sending node is the ECU 200 being inspected and the receiving node is the inspection device 10, the receiving unit 150 of the inspection device 10 calculates the received values of the SOF, ID, control field, and data field of the received data and compares them with the CRC setting value, thereby determining whether the received message (data) was received normally. CRC_DEL (CRC delimiter) is the field indicating the end of the CRC sequence. CRC and CRC_DEL (CRC delimiter) are also collectively referred to as the CRC field.
[0067] ACK (ACKknowledge) is an acknowledgment field 610 used to determine whether the data sent up to the CRC checkpoint was successfully received by the receiving circuit 230 of the destination node (e.g., the ECU 200 under inspection). The acknowledgment field is 1 bit long. If the sending node (inspection device 10) sends a dominant (logic value 0) acknowledgment, and the receiving node (ECU 200) successfully receives the data up to the CRC checkpoint, it sends a recessive (logic value 1) acknowledgment. If the receiving node malfunctions, it sends an acknowledgment with the acknowledgment field 610 set to (maintained) as dominant (logic value 0).
[0068] ACK_DEL (ACK delimiter) is the field that indicates the end of the ACK field. ACK and ACK_DEL (ACK delimiter) are also collectively referred to as the ACK field. Following ACK_DEL (ACK delimiter), EOF (End Of Frame) is the field to be sent at the end of the data frame.
[0069] (CAN Extended Format)
[0070] The extended format shown in ST62 illustrates a structure different from the standard format (ST61). The basic ID is 11 bits long; the ID in the standard format is referred to as the basic ID in the extended format. Following the basic ID in the extended format is the SRR (Substitute Remote Request Bit), which sets a 1-bit recessive signal. Following the SRR is the IDE (Identifier Extension Bit), which sets a 1-bit recessive signal (logic value 1).
[0071] In the extended format, the identifier field (ID field) consists of an 11-bit basic ID field and an 18-bit extended ID field. That is, in the extended format, the identifier field (ID field) is 29 bits long (11 bits + 18 bits).
[0072] The reservation bits ("r1", "r0") each set a dominant signal of 1 bit length. The DLC (Data Length Code) is a field that indicates how many bytes of data will be sent in the subsequent data fields. The reservation bits ("r1", "r0") and the DLC together are called the control field.
[0073] (CAN FD standard format)
[0074] exist Figure 6B In the diagram, ST63 shows a standard format data frame based on the CAN FD protocol, and ST64 shows an extended format data frame based on the CAN FD protocol. In ST64, the structure from SOF to the data field differs from the standard format of ST63, but the structure after the data field in ST64 is the same as the standard format of ST63.
[0075] exist Figure 6B In ST63 and ST64, the upper line represents the recessive level (logic value 1) signal level, and the lower line represents the dominant level (logic value 0) signal level. Data with a line only on the dominant level side represents dominant data, and data with a line only on the recessive level side represents recessive data. Data with lines on both sides represents data that changes (inverts) to dominant or recessive depending on the transmitted data.
[0076] SOF (Start Of Frame) is a field that indicates the start of data frame transmission. When a slave node transmits a data frame, the initial portion transmitted to indicate the start of the data frame is in a dominant state. The SOF signal level changes from a recessive level (logic value 1) when the bus is idle to a dominant level (logic value 0), thereby enabling the ECU 200 to synchronize its reception processing.
[0077] The CAN FD protocol's arbitration area consists of an ID (Identifier) and a Remote Request Substitution (RRS). Similar to the CAN protocol, the ID, besides identifying the data content and the sending node, is also used to determine the priority of communication arbitration. The RTR (Remote Transmission Request) used in the CAN protocol is replaced by a 1-bit RRS. In the standard format, the identifier field (ID field) is 11 bits long.
[0078] The control area of a CAN FD consists of IDE, FDF, res, BRS, ESI, and DLC. Compared to the CAN protocol, CAN FD adds FDF, BRS, and ESI. Similar to the CAN protocol, IDE is a field used to distinguish between standard formats (e.g., 11 bits) and extended formats (e.g., 29 bits). In the standard format, dominant signals (logic value 0) are set in IDE, while in the extended format, recessive signals (logic value 1) are set in IDE. res is equivalent to the reservation bit in the CAN protocol, and DLC (Data Length Code) indicates how many bytes of data will be sent in subsequent data fields.
[0079] The FDF (FD Format Indicator) field is used to distinguish between the CAN protocol and the CAN FD protocol. It is set to dominant (=0) for the CAN protocol and recessive (=1) for the CAN FD protocol.
[0080] BRS (Bit Rate Switch) is a field used to switch the data phase to a higher speed. The transmitting node switches to a high-speed clock mode at the BRS sampling point. When the BRS is set to a high-speed clock mode, the receiving node responding also switches its clock mode accordingly.
[0081] ESI (Error State Indicator) is a data frame that indicates the error state of the sending node. It is set to explicit in the normal state of an active error (no error has occurred). When the error count exceeds a fixed value starting from an active error, it transitions to an passive error (error passive). In the passive error state, it is set to implicit.
[0082] The DLC (Data Length Code) indicates the number of bytes of data to be sent in the subsequent data field. The data field becomes the data length based on the DLC for the portion of the data to be sent. Within the data field, full bytes are sent starting from the most significant bit (MSB). The CAN protocol's data field is 0 to 8 bytes long (0 to 64 bits long), but in the CAN FD protocol, data up to a maximum of 64 bytes can be sent, and the data length can be selected as 0 to 8, 12, 16, 20, 24, 32, 48, or 64 bytes.
[0083] The CRC (Cyclic Redundancy Check) region of the CAN FD protocol consists of Stuff Count, CRC, and CRC Delimiter (CRC_DEL).
[0084] The 4-bit Stuff Count is set to the Gray code value (3 bits) obtained by dividing the number of stuff bits before the CRC area by 8 (Stuff bit count modulo 8) and the parity bit (1 bit) of the Gray code value.
[0085] In CRC (Cyclic Redundancy Check), to maintain transmission quality accompanying the increase in data area (data field), the calculation result of the transmitted value is set as follows: starting from SOF, it includes not only the data area bits but also the Stuff Count and padding bits. When the transmitted data is less than 16 bytes, a 17-bit data area is set in the CRC; when the transmitted data exceeds 16 bytes, a 21-bit data area is set in the CRC.
[0086] Similar to the CAN protocol, the CAN FD protocol employs a bit stuffing rule from the SOF (State of Frame) to the end of the data area (data format). In the CRC area, a fixed padding bit is configured at a fixed bit position at the beginning of the CRC area, and the value of the fixed padding bit is set to the opposite of the value of the preceding bit. For example, if the same level state on bus signal lines 31 and 32 has been consecutively transmitted N times (e.g., five times), a state bit (padding bit) opposite to the transmitted state up to this point is inserted. CRC_DEL (CRC delimiter) is the field indicating the end of the CRC sequence. Based on the bit stuffing rule, if the same level state (dominant or recessive) continues for more than N+1 bits (e.g., 6 bits) on bus signal lines 31 and 32, it is treated as a stuffing error.
[0087] Similar to the CAN protocol, the ACK (ACK knowledge) field in the CAN FD protocol consists of ACK and ACK Delimiter (ACK_DEL). ACK (ACK knowledge) is an acknowledgment field 610 used to determine whether the transmitted data up to the CRC check was successfully received by the receiving circuit 230 of the destination node (e.g., the ECU 200 under inspection). The acknowledgment field is 1 bit long. If the sending node (inspection device 10) sends a dominant (logic value 0) acknowledgment, and the receiving node (ECU 200) successfully receives the data up to the CRC check, it sends a recessive (logic value 1) acknowledgment. If the receiving node malfunctions, it sends an acknowledgment with the dominant (logic value 0) setting (maintaining) in the acknowledgment field 610. ACK_DEL (ACK delimiter) is the field indicating the termination of the ACK field. Following ACK_DEL (ACK delimiter), EOF (End Of Frame) is a field to be sent when the data frame ends.
[0088] (CAN FD Extended Format)
[0089] The extended format shown in ST64 illustrates a structure different from the standard format (ST63). The basic ID is 11 bits long; the ID in the standard format is also referred to as the basic ID in the extended format. In the extended format, following the basic ID is the SRR (Substitute Remote Request Bit), which sets a 1-bit dominant signal. Following the SRR is the IDE (Identifier Extension Bit), which sets a 1-bit recessive signal (logic value 1).
[0090] In the extended format, the identifier field (ID field) (implicitly) consists of an 11-bit basic ID field and an 18-bit extended ID field. That is, in the extended format, the identifier field (ID field) (implicitly) consists of 29 bits (= 11 bits + 18 bits).
[0091] [Inspection Processing Flow]
[0092] Next, the process of performing inspection using the inspection device 10 of this embodiment will be described. Figure 4 This is a diagram illustrating the process flow of inspection using inspection device 10. (and) Figure 4 The inspection process will be explained together. Figure 3 The processing of each part of the functional structure of the inspection device 10 shown.
[0093] In step S400, the operator performing the inspection uses the connection part 30 to connect the inspection device 10 to the communication circuit 210 of the ECU 200 of the object being inspected one-to-one.
[0094] Then, in step S410, the power supply to the inspection device 10 is turned on. Additionally, power is supplied to the ECU 200 of the inspection target 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 of the inspection target.
[0095] [ECU 200 transmission function check]
[0096] In step S420, the initial message confirmation unit 110 confirms whether an initial message has been sent from the transmission circuit 220 of the ECU 200. Here, an initial message refers to a message initially sent from the ECU 200 after power is supplied to the ECU 200, based on a predetermined data format. The initial message confirmation unit 110 confirms whether an initial message has been sent from the transmission circuit 220 of the ECU after power is supplied to the ECU 200 from the power supply unit 105 or after power is supplied to the ECU 200 from the vehicle side.
[0097] 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) from the initial message confirmation unit 110. If the malfunction continues during consecutive determination times (first consecutive determination time, second consecutive determination time), the transmission function determination unit 120 determines that the transmission function of the ECU 200 is malfunctioning. If an initial message is output from the transmission circuit 220 of the ECU 200 within a predetermined consecutive determination time, the transmission function determination unit 120 determines that the transmission circuit 220 of the ECU 200 is normal. Conversely, if no initial message is output from the transmission circuit 220 of the ECU 200 within a predetermined consecutive determination time, the transmission function determination unit 120 determines that the transmission circuit 220 of the ECU 200 is malfunctioning. According to the inspection device 10 of this embodiment, the CAN communication function (transmission function) of the ECU 200 to be inspected can be checked. Furthermore, the confirmation of the presence or absence of an initial message, such as... Figure 8 The process in steps S820 and S870 differs in that it does not check for the presence or absence of errors. In this embodiment, message reception is performed without detecting any of the errors, such as CRC errors, form errors, and stuff errors, as will be explained later in step S435. In this respect, the confirmation of the presence or absence of an initial message differs from that in message reception.
[0098] Then, in step S430, the function determination unit 120 causes the inspection device 10 to display the determination result on a display unit (not shown). The display unit can be, for example, an indicator that allows visual confirmation of the determination result, or a display device such as a liquid crystal or organic EL display. Furthermore, it is not limited to visual display; for example, a speaker (sound source) (not shown) can switch between a notification tone during normal determination and a notification tone during malfunction. Thus, the operator performing the inspection can confirm the determination result of the inspection device 10 visually or audibly.
[0099] [ECU 200 receiver function check]
[0100] In order to perform a receiving function check on the ECU 200, the inspection device 10 determines the transmission speed (bit rate) and data format in CAN communication based on the messages sent from the ECU 200 (S435). The inspection device 10 determines the bit rate and format of the messages received from the transmitting circuit 220 of the ECU 200 (either the initial output message or messages sent after the initial message).
[0101] (Bit rate determination (message reception))
[0102] In step S435, the receiving unit 150 determines the transmission speed (bit rate) in CAN communication based on the message received from the ECU 200. By determining the message transmission speed (bit rate), messages can be received from the ECU 200 without errors, and the data format can be correctly determined in the subsequent step S440. Figure 8 This is a diagram illustrating the specific process of determining the transmission speed (bit rate).
[0103] In step S810, the receiving unit 150 sets the initial value of the bit rate to 1 Mbps.
[0104] In step S820, the receiving unit 150 determines whether it can receive messages from the ECU 200 based on the initial value setting (S810). If the CRC calculated based on the message is inconsistent with the CRC value contained in the message, the receiving unit 150 considers it a CRC error (S820: "No") and proceeds to step S830.
[0105] In addition, CRC_DEL (CRC delimiter), ACK_DEL (ACK delimiter), and EO F in the message are usually determined to be recessive (logical value 1). Here, if a dominant (logical value 0) is detected, it is considered to be a form error (S820: "No"), and the process proceeds to step S830.
[0106] In addition, the receiving unit 150 monitors whether the bit filling rule is followed. If the state of the same level on the bus signal lines 31 and 32 continues for a predetermined number of bits (e.g., 6 bits) or more, it considers the filling error to be incorrect (S820: "No") and proceeds to step S830.
[0107] If the receiving unit 150 detects at least one of the following errors: CRC error, form error, and stuff error, it proceeds to step S830.
[0108] In step S830, the receiving unit 150 decreases the initial bit rate (1 Mbps → 500 Kbps) and determines whether a message can be received (S820). If a message cannot be received (S820: "No"), the receiving unit 150 decreases the bit rate value sequentially (500 Kbps → 250 Kbps → 125 Kbps) and determines whether a message can be received (S820).
[0109] If the receiving unit 150 does not detect any of the errors, such as CRC error, format error, or padding error, it determines that it can receive the message (S820: "Yes") and proceeds to step S840.
[0110] In step S840, the receiving unit 150 determines the bit rate at which messages can be received without errors. For example, if a message is received without detecting any of the errors, such as CRC errors, format errors, and padding errors, at a setting of 250Kbps, the receiving unit 150 determines the bit rate of the message to be 250Kbps.
[0111] Then, in step S850, the receiving unit 150 determines whether the FDF value of the message format is 1. If the FDF value is not 1 (S850: "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 S840. On the other hand, if FDF = 1 in the determination in step S850 (S850: "Yes"), the process proceeds to step S860.
[0112] Then, in step S860, the receiving unit 150 sets the initial value of the bit rate of the CAN FD protocol to 1 Mbps.
[0113] In step S870, the receiving unit 150 determines whether it can receive messages from the ECU 200 based on the initial value setting (S860). Similar to the determination process in step S820, the receiving unit 150 determines whether there are any errors. In step S870, if the receiving unit 150 detects at least one of the following errors: CRC error, format error, and stuffing error, the process proceeds to step S880.
[0114] In step S880, the receiving unit 150 increases the bit rate of the initial value (1Mbps→2Mbps) and determines whether a message can be received (S870). If a message cannot be received (S870: "No"), the receiving unit 150 increases the bit rate value sequentially (2Mbps→4Mbps→5Mbps→8Mbps) and determines whether a message can be received (S870).
[0115] If the receiving unit 150 does not detect any of the errors, such as CRC error, format error, or padding error, it determines that it can receive the message (S870: "Yes") and proceeds to step S890.
[0116] In step S890, the receiving unit 150 determines the bit rate at which messages can be received without errors. For example, if a message can be received at 8 Mbps without detecting any errors, including CRC errors, format errors, and padding errors, the receiving unit 150 determines the message bit rate to be 8 Mbps. Then, after step S890, this process returns to step S435. In this case, the transmission speed (bit rate) in the CAN FD protocol becomes the value determined in step S890. Through the above processing, the determination process for the transmission speed (bit rate) ends.
[0117] (Data format identification)
[0118] In step S440, the receiving unit 150 determines the data format of the message sent from the ECU 200. Figure 9 It is a diagram illustrating the specific process of data format identification and processing.
[0119] In step S435, the receiving unit 150 determines the bit rate. This process is performed previously in Figure 8 As described in the process, the receiving unit 150 obtains the transmission speed (bit rate) of the sent message based on the processing in step S435.
[0120] In step S910, 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) (S910: "True"), the receiving unit 150 proceeds to S920.
[0121] In step S920, 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) (S920: "True"), the receiving unit 150 proceeds to S940.
[0122] Then, in step S940, the receiving unit 150 determines the format of the received message as the standard format of the CAN protocol (11-bit CAN).
[0123] On the other hand, if the signal of FDF is set to be recessive (FDF=1) in the determination in step S920 (S920: "pseudo"), the receiving unit 150 causes the processing to proceed to S950.
[0124] Then, in step S950, the receiving unit 150 determines the format of the received message as the standard format of the CAN FD protocol (11-bit CAN FD).
[0125] On the other hand, if the determination in step S910 is set to the case where the IDE signal is recessive (IDE=1) (S910: "false"), the receiving unit 150 causes the processing to proceed to S930.
[0126] In step S930, 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) (S930: "True"), the receiving unit 150 proceeds to S960.
[0127] Then, in step S960, the receiving unit 150 determines the format of the received message as the extended format of the CAN protocol (29-bit CAN).
[0128] On the other hand, if the signal of FDF is set to be recessive (FDF=1) in the determination of step S930 (S930: "pseudo"), the receiving unit 150 causes the processing to proceed to S970.
[0129] Then, in step S970, the receiving unit 150 determines the format of the received message as an extended format of the CAN FD protocol (29-bit CAN FD). The format determination process ends after the above steps.
[0130] (Check message 600 generation)
[0131] In step S450, the inspection message generation unit 130 generates an inspection message 600 corresponding to the communication protocol of the ECU 200 being inspected, based on the determination result of the transmission speed (bit rate) (S435) and the determination result of the data format (S440). Through this step, the inspection message generation unit 130 generates an inspection message 600, which is generated by setting a predetermined signal level in the confirmation field 610 of the data format corresponding to the message received from the ECU 200 being inspected.
[0132] The receiving function determination unit 170 of the inspection device 10 is based on the inspection message 600 ( Figure 6A , Figure 6B The ECU 200's receiving function is determined by whether the signal level (logic value) set in the ACK field 610 changes (reverses) in the response message from the ECU 200. Figure 5 This is a schematic diagram illustrating the process from receiving a message sent from ECU 200 (bit rate determination: S435), determining the data format of the message (S440), checking the generation of message 600 (S450), until the sending of message 600 is checked (S460).
[0133] The data formats of messages in CAN communication are diverse. However, in the inspection device 10 of this embodiment, different data formats are stored for each ECU to be inspected. The data format can be automatically determined, and an inspection message corresponding to the communication protocol of the ECU 200 to be inspected can be generated based on the determination result of transmission speed (bit rate) (S435) and the determination result of data format (S440).
[0134] Therefore, compared to the situation where the operator has to prepare by matching the specifications of the ECU 200 to the inspection, the operator's burden can be reduced and the inspection can be carried out in a shorter time.
[0135] In order to determine the data format, the inspection message generation unit 130 of this embodiment has an accumulation unit 133 and a selection unit 135. Figure 3 The storage unit 133 stores data formats classified based on combinations of multiple communication protocol types, frame rates, and transmission speeds. The selection unit 135 selects a data format from the storage unit 133 that corresponds to the message received from the transmission circuit 220 of the ECU 200. The storage unit 133 is, for example, a storage medium capable of non-volatilely storing various data formats, such as a hard disk drive or flash memory.
[0136] The storage unit 133 stores data formats classified based on combinations of communication protocol type (e.g., CAN, CAN FD, etc.), frame rate (e.g., 11-bit, 29-bit, etc.), and transmission speed (e.g., CAN: 125Kbps, 250Kbps, 500Kbps, 1Mbps; CAN FD: 1Mbps, 2Mbps, 4Mbps, 5Mbps, 8Mbps, etc.). Furthermore, the data format classification examples are merely illustrative and not limited to these examples.
[0137] The inspection message generation unit 130 generates an inspection message 600 based on the data format selected by the selection unit 135. Figure 6A , Figure 6B For example, when the selection unit 135 selects the type of communication protocol (CAN FD), frame rate (29 bits), and transmission speed (8 Mbps) data format from the storage unit 133, the inspection message generation unit 130 generates an inspection message based on the data format selected by the selection unit 135.
[0138] In this step, the inspection message generation unit 130 generates an inspection message 600 corresponding to the data format of each ECU 200 being inspected through an automatic data format discrimination function. The inspection message generation unit 130 generates an inspection message 600 that is configured with a predetermined signal level in the ACK field 610 of the data format to determine whether the receiving circuit 230 of the ECU 200 can normally receive the inspection message 600.
[0139] In this embodiment, the check message generation unit 130 generates, for example, a check message 600, which is generated by setting the logic value 0 (dominant level) in the acknowledgment field (ACK field) 610 as a predetermined signal level.
[0140] (Check message 600 being sent)
[0141] Then, in step S460, the sending unit 140 sends the inspection message 600 generated by the inspection message generation unit 130 to the receiving circuit 230 of the ECU 200. The sending unit 140 sends the inspection message 600 to the ECU 200 at the transmission speed determined in S435.
[0142] The ECU 200 processes the received inspection message 600 in the receiving circuit 230 and sends a response message to the inspection device 10 as a response to the inspection message 600. Figure 7 This is a schematic diagram illustrating the process from receiving the response message sent from ECU200 (S470), confirming the signal level of the acknowledgment field (ACK field) in the response message (S480), to determining the reception function (S490).
[0143] (Receiving the response message)
[0144] In step S470, the receiving unit 150 receives a response message for the inspection message 600 from the transmitting circuit 220 of the ECU 200.
[0145] (Confirm the setting of the ACK field)
[0146] The CAN communication protocol specifies the following rule: after receiving a message, the ECU responds by changing (inverting) the signal level of the ACK field 610. In this embodiment, to determine whether the receiving function in the ECU 200 is normal, the confirmation unit 160 checks whether the signal level of the ACK field has changed (inverted). A change (inversion) is, for example, a change in signal level from logic value 0 (dominant level) to logic value 1 (recessive level). The ACK field 610 is 1 bit long. If the sending node, i.e., the checking device 10, sends a dominant (logic value 0) ACK, and the receiving node, i.e., the ECU 200, can normally receive data up to the CRC field, it sends a recessive (logic value 1) ACK response. If the receiving ECU 200's sending function (receiving function) malfunctions, it sends an ACK response with the ACK field 610 set to (maintained) as dominant (logic value 0).
[0147] In step S480, the confirmation unit 160 confirms whether the signal level of the acknowledgment field (ACK field) in the response message has changed relative to the setting of the signal level of the acknowledgment field (ACK field) in the check message 600. In the check message 600 of this embodiment, the signal level of the acknowledgment field (ACK field) is set to a logic value of 0 (dominant level) as a predetermined signal level.
[0148] The confirmation unit 160 confirms whether the signal level of the ACK field in the response message has changed relative to the setting of the check message 600. That is, it confirms whether the setting of logic value 0 (dominant level) is changed to logic value 1 (recessive level) or remains at the setting of logic value 0 (dominant level).
[0149] (Processing for determining the receiving function)
[0150] In step S490, the receiving function determination unit 170 determines whether the receiving function of the receiving circuit 230 of the ECU 200 is normal based on the confirmation from the confirmation unit 160. In this step, if the signal level of the confirmation field 610 in the response message changes relative to the setting of the check message 600 during the first or second consecutive determination time, the receiving function determination unit 170 determines that the communication function (receiving function) of the ECU 200 is normal. Conversely, if the signal level of the confirmation field 610 in the response message remains unchanged relative to the setting of the check message during the first or second consecutive determination time, the receiving function determination unit 170 determines that the communication function (receiving function) of the ECU 200 is malfunctioning. When the receiving circuit 230 of the ECU 200 normally receives the check message, it converts the value of the confirmation field (ACK field) from logic value 0 (dominant level) to logic value 1 (recessive level) into a receiving signal RXD, and outputs the converted receiving signal RXD to the controller 240.
[0151] The controller 240 generates an acknowledgment message (TXD) based on the received signal RXD and outputs it to the transmitting circuit 220. The value of the acknowledgment field (ACK field) set in the acknowledgment message sent from the transmitting circuit 220 reflects the result of the transformation processing in the receiving circuit 230.
[0152] Following the rules of the CAN communication protocol, if the receiving function in the receiving circuit 230 is normal, the signal level of the ACK field 600 in the response message will change (invert) from logic value 0 (dominant level) to logic value 1 (recessive level). In this case, the receiving function determination unit 170 determines that the receiving function in the ECU 200 (receiving circuit 230) is normal. On the other hand, if the receiving function of the ECU 200 (receiving circuit 230) malfunctions, the signal level of the ACK field 610 in the response message remains at logic value 0 (dominant level). In this case, the receiving function determination unit 170 determines that the receiving function in the ECU 200 (receiving circuit 230) malfunctions. If the signal level of the ACK field in the response message changes relative to the setting of the check message 600 during the first or second consecutive determination time set by the determination time change unit 180, the receiving function determination unit 170 determines that the receiving function of the ECU 200 is normal. Furthermore, if the signal level of the confirmation field in the response message remains unchanged relative to the setting of the inspection message 600 during the first or second consecutive determination time, the receiving function determination unit 170 determines that the receiving function of the ECU 200 is in a malfunctioning state.
[0153] In step S495, 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. Through the above processing, the series of inspection processes of the inspection device 10 ends.
[0154] (Modified Example)
[0155] The change (reversal) of the signal level in the confirmation field 610 is not limited to the implementation described above; it can also be a change in signal level from logic value 1 (recessive level) to logic value 0 (dominant level). In this case, the sending node, i.e., the checking device 10, performs a recessive (logic value 1) transmission, and the receiving node, i.e., the ECU 200, sends a dominant (logic value 0) confirmation response if it can normally receive data up to the CRC field. If the transmitting function (receiving function) of the receiving ECU 200 malfunctions, it sends a confirmation response with the confirmation field 610 set (maintained) to recessive (logic value 1).
[0156] In this case, the confirmation unit 160 can confirm (determine) whether the setting of logic value 1 (recessive level) is changed to logic value 0 (dominant level) in the response message or the setting of logic value 1 (recessive level) is maintained.
[0157] (Summary of Implementation Methods)
[0158] The above embodiments describe at least the following inspection device 10 and inspection method.
[0159] First aspect: The inspection apparatus of the above embodiment is an inspection apparatus 10 for inspecting the CAN communication function of the ECU 200 to be inspected, and includes:
[0160] The connecting part 30 connects the communication circuit of the ECU to the inspection device one-to-one;
[0161] The inspection message generation unit 130 generates an inspection message that is formed by setting a predetermined signal level in the confirmation field of the data format corresponding to the message received from the ECU of the inspection target.
[0162] The transmitting unit 140 sends the inspection message to the ECU;
[0163] The receiving unit 150 receives a response message from the ECU in response to the inspection message;
[0164] The confirmation unit 160 confirms whether the signal level of the confirmation field in the response message has changed relative to the setting of the check message; and
[0165] The receiving function determination unit 170 determines whether the receiving function of the ECU is normal based on the confirmation of the confirmation unit.
[0166] According to the inspection apparatus of the first aspect, the CAN communication function (receiving function) of the ECU of the inspection object can be inspected. As a result, the CAN communication function (receiving function) of the ECU of the inspection object can be inspected without performing inspection based on the replacement of good parts, thereby reducing the cost of good parts equipment prepared for inspection and reducing the time required for equipment replacement operations during inspection.
[0167] Second aspect: The inspection device of the above embodiment also includes:
[0168] Power supply unit 105 supplies power to the ECU;
[0169] The initial message confirmation unit 110 confirms whether an initial message has been sent from the ECU of the object under inspection; and
[0170] The transmission function determination unit 120 determines whether the transmission function of the ECU is normal based on whether the initial message is present or not, as confirmed by the initial message confirmation unit.
[0171] The initial message confirmation unit 110 confirms whether the initial message was sent from the ECU after the power supply unit supplies power to the ECU or after the power supply unit supplies power to the ECU from the vehicle side.
[0172] According to the inspection device of the second aspect, the CAN communication function (transmission function) of the ECU of the inspection object can be inspected. As a result, the CAN communication function (transmission function) of the ECU of the inspection object can be inspected without performing inspection based on the replacement of good parts, which can reduce the cost of good parts equipment prepared for inspection, and reduce the time required for equipment replacement operations during inspection.
[0173] Thirdly, the inspection message generation unit 130 further comprises:
[0174] Storage unit 133 stores data formats classified based on a combination of communication protocol type, frame rate, and transmission speed; and
[0175] The selection unit 135 selects from the storage unit a data format corresponding to the message received from the ECU.
[0176] The inspection message generation unit 130 generates the inspection message based on the data format selected by the selection unit.
[0177] According to the inspection device of the third aspect, it is possible to automatically determine the data format of the message received from the ECU, and generate an inspection message with a data format corresponding to the message received from the ECU based on the determination result. As a result, compared with the situation where the operator has to prepare by matching the specifications of the ECU to the inspection, the operator's burden can be reduced, and the inspection can be performed in a shorter time.
[0178] Fourth aspect: The inspection device 10 of the above embodiment also includes a determination time changing unit 180, which changes the continuous determination time used to determine whether the CAN communication function is normal from a first continuous determination time to a second continuous determination time that is shorter than the first continuous determination time based on the input from the sensitivity switching unit.
[0179] Fifthly: The receiving function determination unit 170 determines whether the receiving function of the ECU is normal based on the first continuous determination time.
[0180] If 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 based on the second continuous determination time.
[0181] Sixth aspect: If, during the first or second consecutive determination time, the signal level of the confirmation field in the response message changes relative to the setting of the check message, the receiving function determination unit 170 determines that the receiving function of the ECU is normal.
[0182] If the signal level of the confirmation field in the response message remains in a state relative to the setting of the inspection message during the first continuous determination time or the second continuous determination time, the receiving function determination unit 170 determines that the receiving function of the ECU is in a malfunctioning state.
[0183] According to the inspection devices of aspects 4, 5 and 6, even for ECUs in operating states where malfunctions are difficult to occur continuously, continuous abnormalities can be detected within a short sampling time.
[0184] The seventh aspect: The inspection method of the above embodiment is an inspection method of an inspection device 10 that is connected one-to-one with the communication circuit of the ECU of the ECU under inspection via the connection part 30 and inspects the CAN communication function of the ECU of the ECU under inspection, the inspection method comprising:
[0185] The inspection message generation unit 130 of the inspection device generates an inspection message (S450) by setting a predetermined signal level in the confirmation field of the data format corresponding to the message received from the ECU of the object being inspected.
[0186] The process (S460) in which the sending unit 140 of the inspection device sends the inspection message to the ECU;
[0187] The process (S470) in which the receiving unit 150 of the inspection device receives a response message for the inspection message from the ECU;
[0188] In the confirmation process (S480), the confirmation unit 160 of the inspection device confirms whether the signal level of the confirmation field in the response message has changed relative to the setting of the inspection message; and
[0189] The receiving function determination unit 170 of the inspection device determines whether the receiving function of the ECU is normal based on the confirmation result in the confirmation process (S490).
[0190] According to the inspection method in the seventh aspect, the CAN communication function (receiving function) of the ECU of the inspection object can be inspected. Therefore, the CAN communication function (receiving function) of the ECU of the inspection object can be inspected without performing inspections based on replacement of good parts, thus reducing the cost of good parts equipment prepared for inspection and the time required for equipment replacement during inspection operations.
[0191] (Other implementation methods)
[0192] The present invention may involve providing a program that implements the functions of the above-described embodiments to a system or an inspection device constituting the system via a network or storage medium, and having one or more processors in the computer of the inspection device read out the program to execute the processing of the inspection device.
[0193] The invention is not limited to the above-described embodiments, and various modifications and alterations can be made within the scope of the spirit of the invention.
Claims
1. An inspection device for inspecting the CAN communication function of an ECU (Electronic Control Unit) of an object to be inspected, characterized in that it comprises: A connecting part that connects the communication circuit of the ECU to the inspection device one-to-one; The inspection message generation unit generates an inspection message that is formed by setting a predetermined signal level in the confirmation field of the data format corresponding to the message received from the ECU of the inspection object; The sending unit sends the inspection message to the ECU; A receiving unit that receives a response message from the ECU in response to the inspection message; The confirmation unit confirms whether the signal level of the confirmation field in the response message has changed relative to the setting of the check message; as well as The receiving function determination unit determines whether the receiving function of the ECU is normal based on the confirmation from the confirmation unit. The inspection message generation unit also has: The storage unit stores data in formats categorized based on a combination of communication protocol type, frame rate, and transmission speed; and The selection unit selects a data format from the storage unit that corresponds to the message received from the ECU. The inspection message generation unit generates the inspection message based on the data format selected by the selection unit. The inspection device also includes: The power supply unit supplies power to the ECU; An initial message confirmation unit confirms whether an initial message has been sent from the ECU of the object under inspection; as well as The transmission function determination unit determines whether the ECU's transmission function is normal based on whether the initial message is present, as confirmed by the initial message confirmation unit. The initial message confirmation unit confirms whether the initial message was sent from the ECU after the power supply unit supplies power to the ECU or after the power supply unit supplies power to the ECU from the vehicle side.
2. An inspection device for inspecting the CAN communication function of an ECU (Electronic Control Unit) of an object to be inspected, characterized in that the inspection device comprises: A connecting part that connects the communication circuit of the ECU to the inspection device one-to-one; The inspection message generation unit generates an inspection message that is formed by setting a predetermined signal level in the confirmation field of the data format corresponding to the message received from the ECU of the inspection object; The sending unit sends the inspection message to the ECU; A receiving unit that receives a response message from the ECU in response to the inspection message; The confirmation unit confirms whether the signal level of the confirmation field in the response message has changed relative to the setting of the check message; as well as The receiving function determination unit determines whether the receiving function of the ECU is normal based on the confirmation from the confirmation unit. It also includes a determination time modification unit, which, based on input from a sensitivity switching unit, changes the continuous determination time used to determine whether the CAN communication function is normal from a first continuous determination time to a second continuous determination time that is shorter than the first continuous determination time. If, during the first or second consecutive determination time, the signal level of the confirmation field in the response message changes relative to the setting of the check message, the receiving function determination unit determines that the ECU's receiving function is normal. If, during the first or second consecutive determination time, the signal level of the confirmation field in the response message remains in a state relative to the setting of the inspection message, the receiving function determination unit determines that the receiving function of the ECU is in a malfunctioning state.
3. The inspection device according to claim 2, characterized in that, The receiving function determination unit determines whether the receiving function of the ECU is normal based on the first continuous determination time. If 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 based on the second continuous determination time.
4. An inspection method comprising an inspection device that is connected one-to-one with the communication circuit of an ECU to be inspected via a connecting part and inspects the CAN communication function of the ECU to be inspected, the inspection method being characterized in that it includes: The inspection message generation unit of the inspection device generates an inspection message by setting a predetermined signal level in the confirmation field of the data format corresponding to the message received from the ECU of the object being inspected. The process by which the sending unit of the inspection device sends the inspection message to the ECU; The process of the receiving unit of the inspection device receiving a response message in response to the inspection message from the ECU; In the confirmation process, the confirmation unit of the inspection device confirms whether the signal level of the confirmation field in the response message has changed relative to the setting of the inspection message; The process by which the receiving function determination unit of the inspection device determines whether the receiving function of the ECU is normal based on the confirmation result in the confirmation process; The process by which the power supply unit of the inspection device supplies power to the ECU; The initial message confirmation unit of the inspection device confirms whether an initial message has been sent from the ECU of the object being inspected; and The process by which the transmission function determination unit of the inspection device determines whether the transmission function of the ECU is normal based on whether the initial message is present or not, as confirmed by the initial message confirmation unit. The initial message confirmation unit confirms whether an initial message was sent from the ECU after power was supplied from the power supply unit to the ECU or after power was supplied from the vehicle side to the ECU. The inspection message generation unit also has: The storage unit stores data in formats categorized based on a combination of communication protocol type, frame rate, and transmission speed; and The selection unit selects a data format from the storage unit that corresponds to the message received from the ECU. In the process performed by the inspection message generation unit, the inspection message is generated based on the data format selected by the selection unit.
5. An inspection method comprising an inspection device that is connected one-to-one with the communication circuit of an ECU to be inspected via a connecting part and inspects the CAN communication function of the ECU to be inspected, the inspection method being characterized in that it includes: The inspection message generation unit of the inspection device generates an inspection message by setting a predetermined signal level in the confirmation field of the data format corresponding to the message received from the ECU of the object being inspected. The process by which the sending unit of the inspection device sends the inspection message to the ECU; The process of the receiving unit of the inspection device receiving a response message in response to the inspection message from the ECU; In the confirmation process, the confirmation unit of the inspection device confirms whether the signal level of the confirmation field in the response message has changed relative to the setting of the inspection message; as well as The receiving function determination unit of the inspection device determines whether the receiving function of the ECU is normal based on the confirmation result in the confirmation process. The determination time modification unit of the inspection device, based on input from the sensitivity switching unit, changes the continuous determination time used to determine whether the CAN communication function is normal from a first continuous determination time to a second continuous determination time that is shorter than the first continuous determination time. If, during the first or second consecutive determination time, the signal level of the confirmation field in the response message changes relative to the setting of the check message, the receiving function determination unit determines that the ECU's receiving function is normal. If, during the first or second consecutive determination time, the signal level of the confirmation field in the response message remains in a state relative to the setting of the inspection message, the receiving function determination unit determines that the receiving function of the ECU is in a malfunctioning state.