JP2008072328A - Evaluating device for gateway ecu - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an evaluating device capable of precisely evaluating the relay function of a gateway device, thereby inexpensively and highly precisely evaluating the relay function of the gateway device. <P>SOLUTION: The evaluating device 10 is connected to a gateway ECU (Electric Control Unit) 30 through a CAN (Controller Area Network) 1 bus 21 and a CAN2 bus 22. A first microcomputer (CPU_1) 13 transmits relay frames (frames A and B) relayed by the gateway ECU 30. A third microcomputer (CPU_3) 15 evaluates the relay time of the gateway ECU 30 from time differences between frames (frames A' and B') which are relayed by the gateway ECU 30 among the frames transmitted from the first microcomputer 13 and frames (frames A and B) which are not relayed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an evaluation apparatus for a gateway ECU. Specifically, the present invention relates to an evaluation device that accurately evaluates a relay function of a gateway ECU.

  Conventionally, there is a communication protocol called CAN (Controller Area Network) as an in-vehicle network of an automobile (for example, Non-Patent Documents 1 and 2 below). CAN is a serial communication protocol internationally standardized by ISO (International Organization for Standardization) (ISO11891, ISO11519).

  In an in-vehicle LAN using CAN, an ECU (Electric Control Unit) for controlling the hardware of the automobile is connected via a CAN bus, and each CAN bus is connected via a gateway device.

  For example, a CAN bus to which an engine ECU for controlling an engine or the like is connected and a CAN bus to which an information ECU for controlling a navigation system or the like is connected are connected via a gateway device.

  A feature of the CAN protocol is a multi-master system in which all nodes (ECUs) can start transmitting messages (hereinafter referred to as “frames”, one communication unit in CAN) when the bus is free.

  On the other hand, the gateway device relays the frame between the CAN buses such as transferring a frame from a certain ECU to another ECU connected to another CAN bus.

As described above, in an in-vehicle LAN using CAN, it is important to relay a frame within a predetermined time via a gateway device. Therefore, it is important to evaluate in advance how long it takes to relay a frame through the gateway device. Therefore, the proposal of the evaluation apparatus which evaluates the relay time has been desired.
“CAN Introduction” www.renesas.com “What is CAN?” Www.toyo.co.jp/car/CAN/CAN_General.htm

  However, when the relay time is evaluated using an existing measuring machine, if a plurality of channels are measured at the same time, it is necessary to provide each measuring machine for each channel, and the measuring machines must be synchronized. Therefore, the equipment becomes complicated and expensive.

  Further, the existing measuring machine has a problem that the accuracy when measuring the relay time is low, such as “100 μs”. For example, an evaluation apparatus capable of evaluating with high accuracy such as “1 μs” is desired.

  The present invention has been made in view of the above problems, and an object thereof is to provide an evaluation device that accurately evaluates a relay function of a gateway device.

  Another object of the present invention is to provide an evaluation device that evaluates the relay function of a gateway device at low cost and with high accuracy.

  In order to achieve the above object, according to an embodiment of the present invention, an evaluation device for a gateway device that connects a plurality of CAN buses and relays a frame transferred to the CAN bus transmits the frame. Of the frames transmitted from the transmitter, the transmitter receives the first frame relayed through the gateway device and the second frame not relayed through the gateway device, and receives the first frame and the frame And an evaluation unit that evaluates the gateway device based on a second frame.

  According to another embodiment of the present invention, in the evaluation device, the evaluation unit includes a first channel unit that receives the first frame and a second channel that receives the second frame. And a section.

  Further, according to another embodiment of the present invention, in the evaluation device, the evaluation unit relays the gateway device by comparing the reception time of the first frame and the reception time of the second frame. It is characterized by evaluating time.

  Furthermore, according to another embodiment of the present invention, the evaluation apparatus further includes a data arrangement table indicating whether or not the first and second frames are relayed to the gateway apparatus, The first frame is relayed based on a data arrangement table, and the second frame is not relayed.

  Furthermore, according to another embodiment of the present invention, in the evaluation device, the transmission unit adds the first frame to the data field of the first frame relaying the gateway device according to a predetermined rule. An identification code is inserted every time and the first frame is transmitted.

Furthermore, according to another embodiment of the present invention, in the evaluation apparatus, the transmission unit includes at least two transmission channel units,
When there is the second frame with the same ID that does not relay the gateway device, the transmission unit obtains a value obtained by inverting the data value inserted in the data field of the second frame from one transmission channel unit. The second frame as a data value is transmitted.

  ADVANTAGE OF THE INVENTION According to this invention, the evaluation apparatus which evaluates the relay function of a gateway apparatus accurately can be provided. Furthermore, according to the present invention, it is possible to provide an evaluation device that evaluates the relay function of the gateway device at low cost and with high accuracy.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram illustrating a configuration example of an evaluation apparatus 10 to which the present invention is applied and an example in which the evaluation apparatus 10 is connected to a gateway (G / W) ECU 30.

  The evaluation apparatus 10 is connected to the host PC 40 via the LAN and is connected to the gateway ECU 30 via the CAN buses 21 and 22. The evaluation device 10 transmits a frame to the gateway ECU 30 and measures the subsequent frame on the CAN bus. The host PC 40 performs analysis and the like based on the frame measured by the evaluation apparatus 10.

  The evaluation device 10 includes a motherboard 11 and a CAN board 12. The motherboard 11 includes a CPU, a ROM, a RAM, and the like inside, and controls the entire evaluation apparatus 10.

  The CAN board 12 includes three microcontrollers (hereinafter referred to as “microcomputers”) 13, 14, and 15, and transmits and receives frames to and from the gateway ECU 30. The CAN board 12 is connected to the motherboard 11 via the PCI bus, and outputs a reception result or the like to the motherboard 11.

  The first microcomputer (CPU_1) 13 transmits relay data (relay frame) relayed to the gateway ECU 30 to the CAN1 bus 21. The first microcomputer 13 is a transmission-dedicated microcomputer that transmits a relay frame.

  The second microcomputer (CPU_2) 14 transmits a frame (data not relayed) that is not relayed to the gateway ECU 30. The second microcomputer 14 is a transmission-dedicated microcomputer that transmits non-relay frames.

  The third microcomputer (CPU_3) 15 receives the frames transmitted from the first and second microcomputers 13 and 14, and stores (logs) the frames. The third microcomputer 15 evaluates the relay time and the like from the logged frame. The third microcomputer 15 is a reception-only microcomputer. Details will be described later.

  Each microcomputer 13, 14, 15 has an output stage or an input stage for two channels, and is connected as follows.

  That is, the first channel (upper side in FIG. 1) of the first microcomputer 13 is connected to the gateway ECU 30 via the CAN1 bus 21. The gateway ECU 30 is connected to the second channel of the third microcomputer 15 via the CAN2 bus 22.

  At the output stage of the first channel of the first microcomputer 13, there are a first connection point 24 and a second connection point 25 in order toward the gateway ECU 30.

  The first connection point 24 is connected to the first channel of the second microcomputer 14, and the second connection point 25 is connected to the first channel of the third microcomputer 15.

  On the other hand, on the second channel of the third microcomputer 15, there are a third connection point 26 and a fourth connection point 27 in order toward the gateway ECU 30.

  The third connection point 26 is connected to the second channel of the second microcomputer 14, and the fourth connection point 27 is connected to the second channel of the first microcomputer 13.

  Thus, a frame is transmitted / received from the evaluation apparatus 10 connected to the gateway ECU 30 as follows.

  The first microcomputer 13 transmits “frame A” from the first channel and “frame B” from the second channel.

  “Frame A” is transmitted to the gateway ECU 30 via the first and second connections 24, 25. The gateway ECU 30 relays the “frame A” and transmits it to the second channel of the third microcomputer 15 via the CAN 2 bus 22, the fourth and third connection points 27 and 26.

  In this embodiment, “′” is added to the frame relayed by the gateway ECU 30 to distinguish it from the others. Therefore, “frame A” becomes “frame A ′” when relayed to the gateway ECU 30.

  “Frame A” is also transmitted from the second connection point 25 to the first channel of the third microcomputer 15.

  Furthermore, “frame A” is transmitted from the first connection point 24 to the first channel of the second microcomputer 14, but the second microcomputer 14 discards the received frame. "Is discarded even if it is received.

  On the other hand, “frame B” is transmitted from the fourth connection point 27 to the second channel of the third microcomputer 15 via the third connection point 26.

  Further, “frame B” is transmitted from the fourth connection point 27 to the gateway ECU 30. “Frame B” is relayed to the gateway ECU 30 and transferred to the third microcomputer 15 from the second connection point 25 to the first channel as “frame B ′”.

  “Frame X” is transmitted from the first channel of the second microcomputer 14, and “Frame Y” is transmitted from the second channel.

  “Frame X” is transferred to the first channel of the third microcomputer 15 via the first and second connection points 24, 25. “Frame X” goes from the second connection point 25 to the gateway ECU 30, but the gateway ECU 30 is set so as not to relay even if “frame X” is transmitted, and therefore “frame X” is discarded. Similarly, “frame X” is also transferred from the first connection point 24 to the first microcomputer 13, but the first microcomputer 13 discards this “frame X” even if it is received.

  “Frame Y” is transmitted from the third connection point 26 to the second channel of the third microcomputer 15. “Frame Y” also goes from the third connection point 26 to the gateway ECU 30 via the fourth connection point 27, but “frame Y” is set so as not to be relayed, and is discarded.

  Neither “frame X” nor “frame Y” is relayed to gateway ECU 30 as “outside relay frame”.

  In this way, the third microcomputer 15 assigns “Frame A” and “Frame A ′”, “Frame B ′” and “Frame B”, “Frame X” and “Frame Y” to the first and second channels, respectively. Receive at. The third microcomputer 15 evaluates the gateway ECU 30 from these received frames.

  FIG. 2 is a diagram illustrating a configuration example of the third microcomputer 15. The third microcomputer 15 includes a CPU 151, an I / O (Input / Output) bus 152, and a CAN controller 153.

  The CPU 151 is connected to the CAN controller 153 via the I / O bus 152, and measures the frame relay time for the data from the CAN controller 153. Details will be described later.

  The CAN controller 153 includes two CAN modules 154 and 155 (the first channel is CAN module 1 (154), the second channel is CAN module 2 (155)), a memory access controller 156, a RAM 157, and an interface circuit 158. Prepare.

  The two CAN modules 154 and 155 are connected to the CAN2 bus 22 and transfer the transferred frames to the memory access controller 156, respectively.

  The memory access controller 156 is connected to the RAM 157 and stores frames from the CAN modules 154 and 155 in the RAM 157. The RAM 157 functions as a message buffer in which received frames (received data or messages) are stored.

  The interface circuit 158 serves as an interface with the CPU 151 via the I / O bus 152. The data is converted into a data format that can be read by the CPU 151.

  The operation of the third microcomputer 15 configured as described above is as follows. That is, the frame transferred to the two CAN modules 154 and 155 is transferred to the memory access controller 156.

  The memory access controller 156 stores a frame in the message buffer for each identified frame based on, for example, frame identification information such as an ID inserted into the frame. Each entry is configured for each frame. In the example of FIG. 2, it consists of “N” entries.

  At this time, the memory access controller 156 also stores time information (time stamp information) at which the frame is captured in the same entry. Therefore, time information of each frame is also stored for each frame.

  Furthermore, when the memory access controller 156 receives a message from the CAN bus, the memory access controller 156 outputs an interrupt request to the CPU 151. The interrupt request is transferred to the CPU 151 via the interface circuit 158.

  Based on this interrupt request, the CPU 151 controls the memory access controller 156 to read each frame and its time stamp stored in the message buffer. The CPU 151 obtains these information via the interface circuit 158 and the I / O bus 152. The CPU 151 evaluates the relay time based on such information.

  As described above, in the evaluation apparatus 10, the time information captured by the memory controller 156 in advance is stored in the message buffer, and the evaluation is performed based on the information.

  Therefore, as compared with the case where the CPU 151 performs capture processing in response to an interrupt request and obtains time information (time stamp information), time information with high accuracy can be obtained because there is no time lag from the reception of the frame to the interrupt request. Can do.

  Next, specific processing when the CPU 151 evaluates the gateway ECU 30 will be described. FIG. 3A to FIG. 4 are flowcharts showing specific evaluation processing examples.

  3A shows the relay time calculation / determination process, FIG. 3B shows the relay leak process for determining whether or not there is a frame relay leak to the gateway ECU 30, and FIG. 4 shows the non-relay frame. The relay excess determination process for determining whether ("Frame X", "Frame Y") is relayed to the other channel is shown.

  First, the relay time calculation / determination process shown in FIG.

  When this process is started (S10), the CPU 151 calculates a relay time from the acquired time stamp information (S11).

  For example, for “frame A” and “frame A ′”, the difference between the reception times (time stamp information) is calculated to obtain the relay time.

  Next, the CPU 151 determines whether or not the calculated relay time is within a certain time range (several μs to several tens μs) (S12). If it is within the range (YES), it is assumed that there is no problem with the relay time (S13), and the process is terminated (S14). On the other hand, when it is out of range (NO in S12), it is determined that a problem has occurred in the relay time (S15), and the process is terminated (S14).

  Thus, the relay time is calculated by taking the difference from the reception time of “frame A” and “frame A ′”, that is, the frame received without relaying through the gateway ECU 30 and the frame received through relay. Therefore, the frame relay time for the gateway ECU 30 can be easily evaluated. In addition, it is not necessary to synchronize each device as compared with the case where different devices such as the evaluation of “Frame A” and the evaluation of “Frame A ′” are used, and the evaluation can be performed at a low cost because it can be evaluated with a simple configuration. Equipment can be provided. Furthermore, since it is determined whether or not the relay time is within a certain range, the evaluation can be performed with high accuracy.

  In the example of FIG. 3A, the calculation / determination processing of the relay times of “frame A” and “frame A ′” is shown, but the calculation of the relay times of “frame B” and “frame B ′”, etc. Processing can be realized in the same way. By combining these two, a highly reliable and highly accurate evaluation apparatus can be provided. Furthermore, it is possible to provide an evaluation device with higher accuracy and improved reliability by repeating the operation many times within a predetermined time.

  Next, the relay leakage determination process shown in FIG. When the process is started (S20), the data value in “frame A ′” is compared with the data value in “frame A” (S21). If they are the same (YES), there is no relay omission (S22). ), The process is terminated (S23). On the other hand, when they are different (NO in S21), it is determined that relay leakage has occurred (S24), and the process is terminated (S23).

  As described above, the evaluation apparatus 10 compares the data values of “frame A” and “frame A ′” to determine whether or not relay leakage has occurred. Therefore, the relay leakage can be evaluated with a simple configuration. . By combining with the above-described relay time calculation / determination process, a highly reliable and highly accurate evaluation apparatus can be provided.

  As in the above-described relay time calculation / determination process, the data values of “frame B” and “frame B ′” may be compared, or the process may be repeated for a certain period of time.

  Next, the relay excess determination process shown in FIG. 4 will be described. When the process is started (S30), it is determined whether or not the frame having the ID of “Frame X” is received in the other channel of the third microcomputer (CPU — 3) 15 (S31).

  As described with reference to FIG. 1 and the like, the “frame X” that does not relay the gateway ECU 30 is transferred to the first channel of the third microcomputer 15. For example, it is possible to determine which channel is received in the message buffer, and whether or not a frame having the same ID as “Frame X” is received in the second channel is determined.

  If there is the same ID as “frame X” (YES), the CPU 151 compares the data value in the frame having the same ID with the data value in “frame X” (S32). If they match (YES), it is confirmed that “Frame X” is relayed to the other channel (S33), and the process is terminated (S34).

  On the other hand, when the data values do not match (NO in S32), it is confirmed that “frame X” is not relayed to the other channel (S35), and the process is terminated (S34).

  Also, when there is no frame having the same ID as “Frame X” in the other channel (NO in S31), it is confirmed that “Frame X” is not relayed to the other channel (S35), and the process is terminated. (S34).

  As described above, in the evaluation apparatus 10, since it is confirmed whether not only the relay frame but other non-relay frames are received on the predetermined channel, the evaluation can be performed with higher accuracy. You may combine with each above-mentioned process (FIG. 3 (A) and the same figure (B)).

  Next, an example of evaluating whether or not the relay order has changed will be described. FIG. 5A and FIG. 5B are diagrams showing a concept when the relay order is changed.

  First, FIG. 5A will be described. I want to detect whether or not there is a change between frames with the same ID with the same priority for relay processing, but the IDs of the frames “Frame 1”, “Frame 2”, and “Frame 3” are the same and are inserted. The gateway ECU 30 continuously receives the same (0x00) frame for the value of the data field thus set, and the gateway ECU 30 switches the frame order, and the CAN2 bus 22 in the order of “frame 2”, “frame 1”, “frame 3”. Consider the case of being transferred to.

  When the gateway ECU 30 evaluates whether or not frame replacement has occurred, in the above-described example, if the ID of each frame is the same, a difference such as “frame 1” cannot be identified on the third microcomputer 15 side. Therefore, even if the relay order is changed, this cannot be determined.

  In order to solve this problem, in the present embodiment, an automatically incremented identification code is assigned to each frame relayed to the gateway ECU 30 at the head (first byte) of the data field. Even if the frame IDs are the same, by checking the data area, each frame can be identified even if the frames are exchanged.

  In the example shown in FIG. 5B, “0x01”, “0x02”, and “0x03” are assigned to the data field sequentially from “frame 1”.

  Specifically, the first microcomputer 13 of the evaluation device 10 may add the incremented identification code to the head of the data field of the frame so that each frame is transmitted. Of course, it is only necessary to be able to identify the replacement of each frame by the third microcomputer 15 on the receiving side. Therefore, the decremented identification code, increment by two instead of increment by one, etc. A unique data value (data field value) may be assigned to the.

  Further, as a field to be changed for each frame, not only the data field but also other fields such as an ID field may be corrected. When the ID field is changed, the priority order of the frames is changed by changing the ID. In the CAN protocol, arbitration is performed based on the ID. Therefore, when the ID is changed, it is necessary to change the relationship of the priority order of the frames between the frames having the similar transmission order.

  As described above, the evaluation apparatus 10 can evaluate the switching of the relay order in addition to the calculation of the relay time and the like, and therefore can provide a highly accurate and highly reliable evaluation apparatus.

  The following example will be described. For example, consider the in-vehicle LAN network shown in FIG. Nodes A101 to C103 are connected to the CAN1 bus 21, and nodes D104 to F106 are connected to the CAN2 bus 22. The CAN1 bus 21 and the CAN2 bus 22 are connected to the gateway ECU 30. Note that a CAN1 bus 21 is connected to the channel 1 side of the gateway ECU 30 and a CAN2 bus 22 is connected to the channel 2 side.

  The gateway ECU 30 stores a data arrangement table, and the gateway ECU 30 transfers each frame to each node A 101 or the like based on this table. FIG. 7A shows an example of a data arrangement table in the CAN1 bus, and FIG. 7B shows an example of a data arrangement table in the CAN2 bus.

  As shown in FIG. 7A, the frame of “ID1” is transmitted from the node A101 (“Tx” in the data arrangement table), and is received by the channel 1 of the node B102, the node C103, and the gateway ECU 30 (“Rx”). ).

  On the other hand, the frame of “ID2” is also transmitted from the node A101 and received by the node B102 and the node C103, but is not received by the gateway ECU 30 (even if received, it is discarded). That is, the frame of “ID2” is an “outside relay frame” that does not relay the gateway ECU 30.

  As shown in FIG. 7B, the frame of “ID1” is transmitted from the channel 2 side of the gateway ECU 30 (“Tx”) and received by the node D104 to the node F105 (“Rx”).

  On the other hand, the frame of “ID2” is transmitted from the node D104 and received by the node E105 and the node F105, but is not received on the channel 2 side of the gateway ECU 30. That is, the frame of “ID2” is an “outside relay frame” that does not relay the gateway ECU 30.

  In this way, although the “ID1” frame relays to the gateway ECU 30, the “ID2” frame has the same ID on the CAN1 bus 21 and the CAN2 bus 22 regardless of the “non-relay frame”. For example, when a frame of “ID2” is received in a state where the CAN1 bus 21 is connected to the first channel of the third microcomputer 15 of the evaluation apparatus 10 and the CAN2 bus 22 is connected to the second channel, The evaluation device 10 cannot determine whether this frame is a frame transmitted from the node A 101 or whether the frame transmitted from the node D 104 is a frame relayed by the gateway ECU 30 by mistake.

  Therefore, in this embodiment, the ID is not relayed by the gateway ECU 30, but when the evaluation is performed by transmitting a frame to which the ID used in both the CAN1 bus and the CAN2 bus is assigned, which CAN bus is used. Since it is only necessary to discriminate whether the frame is transmitted as a frame, the data value may be different (for example, the data value is inverted). For example, when the data value of the “ID2” frame on the CAN1 bus side is “0x00”, the data value of the frame with the same ID on the CAN2 bus side may be inverted to “0xFF”.

  FIG. 8 is a flowchart showing an example of such processing. Processing is performed by the second microcomputer 14 of the evaluation apparatus 10.

  When the process is started (S40), the second microcomputer 14 determines a transmission channel (S41). At the time of the first channel (ch1), the transmission data value inserted in the data field of the frame is set to “0x00” (S42). In the case of the second channel (ch2 in S41), the transmission data value is inverted to “0xFF” (S43).

  Then, a DLC (Data Length Code) data length is set in the frame (S44), transmitted to the CAN buses 21 and 22 (S45), and the process is terminated (S46).

  Thus, the evaluation apparatus 10 transmits the data value of the non-relay frame as a unique value for each channel. Even if a frame with the same ID exists in both transmission channels, it is possible to determine a non-relay frame by checking the data value. Therefore, a highly accurate and highly reliable evaluation device can be provided.

  The data arrangement table may be stored in the gateway ECU 30 or may be held for each microcomputer 13, 14, 15 of the evaluation device 30.

  In any of the above-described examples, each of the microcomputers 13, 14, and 15 has been described as including two channel units and transmitting and receiving frames. Of course, each of the microcomputers 13, 14, and 15 may be configured from a plurality of channels such as three or more channels. Even in this case, the present invention can be implemented in exactly the same manner and has the same effects.

It is a figure which shows the structural example by which the evaluation apparatus was connected to gateway ECU. It is a figure which shows the structural example of a 3rd microcomputer. FIG. 3A is a flowchart illustrating an example of relay time calculation / determination processing, and FIG. 3B is a flowchart illustrating an example of relay leakage determination processing. It is a flowchart which shows the example of a relay excess determination process. FIG. 5A shows the concept of frame replacement before countermeasures, and FIG. 5B shows the concept of frame replacement after countermeasures. FIG. 6 is a diagram illustrating a configuration example of the in-vehicle LAN network. FIG. 7A and FIG. 7B are diagrams showing examples of the data arrangement table. It is a flowchart which shows the example of the transmission process of the frame outside a relay.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Evaluation apparatus, 12 CAN board, 13 1st microcomputer (CPU_1), 14 2nd microcomputer (CPU_2), 15 3rd microcomputer (CPU_3), 21 CAN1 bus | bath, 22 CAN2 bus | bath, 30 Gateway ECU, 151 CPU, 153 CAN controller, 156 memory access controller, 157 RAM (message buffer)

Claims (5)

In an evaluation device for a gateway device that relays frames that need to be connected between a plurality of buses and transferred to different buses,
A transmission unit for transmitting a frame;
A receiving unit that receives a first frame in which the frame transmitted from the transmitting unit is relayed by the gateway device and a second frame in which the frame transmitted from the transmitting unit does not pass through the gateway device When,
An evaluation unit that evaluates the gateway device based on the first frame and the second frame;
An evaluation apparatus comprising:   The evaluation apparatus according to claim 1, wherein the receiving unit includes a first channel unit that receives the first frame and a second channel unit that receives the second frame.   The evaluation apparatus according to claim 1, wherein the evaluation unit evaluates the gateway device by comparing a reception time of the first frame with a reception time of the second frame.   The evaluation unit evaluates the gateway device based on information on whether or not the first frame is a frame to be relayed by the gateway device and the presence or absence of the second frame. Item 1. The evaluation apparatus according to Item 1. The bus relayed by the gateway device is a CAN protocol bus,
2. The transmission unit according to claim 1, wherein when a frame having the same ID exists in a plurality of frames to be transmitted, the transmission unit changes contents of a data field of the frame having the same ID. Evaluation device.

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