JP5042005B2 - Communication monitoring device, communication gateway evaluation device, and communication monitoring method - Google Patents

Description

  The present invention provides a plurality of microcomputers each including a receiving unit that receives communication data transmitted via each communication line, and a time stamp processing unit that adds reception time information to the communication data received by the receiving unit. In addition, the present invention relates to a communication monitoring device, a communication gateway evaluation device, and a communication monitoring method including a communication information storage unit that stores communication data received by each microcomputer and reception time information of the communication data.

  Devices connected to a network such as an electronic control unit mounted on a vehicle are inspected at the time of factory shipment. As an electronic control unit, for example, there is a communication gateway that enables communication by mutually relaying data between networks having different communication speeds. There is a check whether the data relay function of the gateway is normal.

  As a method for inspecting whether or not the data relay function is normal, Patent Document 1 discloses that a plurality of electronic control units are connected in series, and data for inspection is transmitted as transmission data from one end of the serial connection. Inspecting the data relay function of a plurality of electronic control units at a time by receiving the test data relayed by a plurality of electronic control units at the end as received data and confirming the received data and the transmitted data An electronic control unit inspection method is disclosed. In this inspection method, inspection is performed by connecting inspection devices to a plurality of electronic control units.

  In the inspection of a device connected to the network, as illustrated in FIG. 1, the communication monitor device 100 is connected to the device to be inspected, and data is transmitted / received between the communication monitor device 100 and the device to be inspected, or Whether data transmitted / received between the device to be inspected and other devices is received by the communication monitor device 100, and the processing speed, timing, and cycle of data transmission / reception are equal to or higher than a predetermined speed set in advance It is determined whether or not, whether it is a predetermined timing, whether it is a predetermined cycle, or the like. At that time, the communication monitoring apparatus 100 executes a so-called time stamp for adding time information to the transmission / reception data, and clarifies the time when the data was transmitted / received.

  For example, as shown in FIG. 2, the communication monitoring apparatus 100 includes a plurality of microcomputers 200 (201 to 20m), and each microcomputer 200 generates a reception interrupt when receiving communication data. Receiver 210 (211 to 21n). Each reception unit 210 includes a latch circuit 220 that stores time information when communication data is received, and a time stamp processing unit 230 that adds the time information to communication data. The time information is a count value by an internal timer circuit 700 provided in each microcomputer 200.

  Then, the communication data to which the time information is added by each time stamp processing unit 230 is output to the communication information storage unit 400 configured by an FPGA or the like via the switch circuit 800 that passes each communication data exclusively and sequentially. And stored in the communication information storage unit 400. Further, the communication information storage unit 400 is managed by a management unit 500 having a CPU or the like, and communication data and time information are transferred to the evaluation unit 600 configured by a general-purpose computer or the like via the management unit 500 and evaluated. The unit 600 evaluates the connection operation of the device to be inspected based on the communication data and the time information.

Further, as such a communication monitoring device, Patent Document 2 discloses a transmission line monitoring device having a data collection function for collecting all data on a transmission line, which is received every time the data collection function receives data. Store the data in the buffer, compare whether the received data is the same as the set data, and if it is the set data, save the cycle current value register in the cycle previous value register and store the receive time stamp in the cycle current value register A transmission line monitoring apparatus is disclosed in which a period is obtained from a difference between a period previous value register and a period current value register and compared with a period preset value to determine whether or not a period deviation has occurred.
JP 2006-228091 A JP 2004-207803 A

  However, in the case of the communication monitoring apparatus 100 as shown in FIG. 2, the internal timer circuit 700 provided in each microcomputer 200 is different from the internal timer circuit 700 provided in the other microcomputer 200. The time information added to the communication data received by the microcomputer 200 cannot be synchronized between the microcomputers 200.

  For example, even when two microcomputers 201 and 202 simultaneously receive communication data and execute a time stamp, the time information added to each communication data may have a different value.

  This will be described in detail below based on the block diagram of FIG. 2 and the time chart of FIG. When the receiving units 211 and 21n of the microcomputer 201 and the receiving units 211 and 21n of the microcomputer 202 simultaneously receive communication data, the time information added by the time stamp processing unit 230 of the microcomputer 201 is shown in FIG. As shown in a), the time information added by the time stamp processing unit 230 of the microcomputer 202 is “B1” which is the count value of the internal timer circuit 700 of the microcomputer 201 when communication data is received. As shown in FIG. 3B, the count value of the internal timer circuit 700 of the microcomputer 202 at the time of communication data reception is “C1”. Since each internal timer circuit 700 provided in each microcomputer 200 is a different circuit, “B1” and “C1” are not necessarily the same value.

  Therefore, as shown in FIG. 4, a reference timer circuit 410 serving as a timer circuit common to the plurality of microcomputers 200 is used in the communication monitoring apparatus 100, and each microcomputer 200 performs a reference process when reading received communication data. It can be considered that the problem described above can be solved by giving the value of the timer circuit 410 to the communication data.

  However, in the case of the configuration of FIG. 4, the count value output by the reference timer circuit 410 is a common count value for each microcomputer 200 and is a synchronized value. If another interrupt process is executed before the data read process is executed, a delay occurs in the read process, and the delay becomes an error.

  In view of the above-described conventional problems, an object of the present invention is a communication monitor capable of reducing the time stamp error caused by the occurrence of another interrupt process while synchronizing the time stamp timing in each microcomputer. An apparatus, a communication gateway evaluation apparatus, and a communication monitoring method are provided.

  In order to achieve the above-described object, the characteristic configuration of the communication monitoring apparatus according to the present invention includes a receiving unit that receives communication data transmitted via each communication line, and reception time information in the communication data received by the receiving unit. A communication monitor device including a plurality of microcomputers each including a time stamp processing unit for providing communication data, and a communication information storage unit that stores communication data received by each microcomputer and reception time information of the communication data. Each time stamp processing unit uses the value of the reference timer circuit common to each microcomputer acquired at the time of reading each communication data, and the value of the internal timer circuit of each microcomputer acquired at the time of receiving and reading each communication data. The reception time information is generated by correcting based on the difference value.

  According to the above configuration, each time stamp processing unit is executed based on the value of the reference timer circuit common to each microcomputer, so that the timing of the time stamp in each microcomputer can be synchronized. In addition, even if another interrupt processing is executed before a time stamp for certain communication data is executed in a certain microcomputer, the time stamp processing unit is obtained at the time of receiving and reading each communication data. Since the value of the reference timer circuit is corrected based on the difference value between the values of the internal timer circuits of the microcomputers, the time stamp error caused by the occurrence of another interrupt process is reduced.

  As described above, according to the present invention, there is provided a communication monitoring apparatus capable of reducing the time stamp error caused by the occurrence of another interrupt process while synchronizing the time stamp timing of each microcomputer. I was able to do it.

  The communication monitoring device according to the present invention will be described below. As shown in FIG. 5A, the communication monitor device 1 is connected to the communication line SL, and is configured to monitor communication data transmitted through each communication line SL.

  For example, the communication line SL is mounted on a vehicle and used for communication between a plurality of electronic control devices that control an engine, a door, and the like. Communication protocols include CAN (Controller Area Network), LIN (Local Interconnect Network), and FlexRay. And MOST (Media Oriented Systems Transport).

  In this embodiment, six types of networks using the CAN protocol, that is, six communication lines SL (SL1 to SL6) are used as communication lines, and one of each communication line is an electronic control unit (ECU). A to F are connected to a communication gateway apparatus G (hereinafter referred to as “communication gateway G”) as an inspection target that mediates communication of the electronic control apparatuses A to F. The communication gateway G is, for example, a drive network used for an electronic control device that controls an engine, a brake, etc., a body network used for an electronic control device that controls a door, etc., and a network used for failure diagnosis For example, a device that connects two or more electronic control devices that are connected to different networks so that they can communicate bidirectionally or unidirectionally. Connect between networks with different protocols and communication speeds.

  In FIG. 5A, an electronic control device is connected to each communication line SL. However, instead of the electronic control device, a simulation device that simulates processing performed by the electronic control device may be connected. Good. That is, as shown in FIG. 5B, a configuration in which the inside of the one-dot chain line in FIG.

  The communication data is defined according to the protocol of the network through which the communication data is transmitted. For example, in the case of the CAN protocol used in the present embodiment, the communication data is a data frame transmitted at the time of data transfer to another electronic control device on the network, and a transmission request is made to another electronic control device on the network. It consists of multiple types of frames, such as a remote frame transmitted at the time, and an error frame transmitted by the electronic control device that has detected a communication error, and each frame includes an arbitration field composed of data identifiers, data It consists of a control field for designating a length, a field such as a data field in which data is stored, and various flags that are switched depending on the presence or absence of an error.

  As shown in FIG. 6, the communication monitor device 1 includes a plurality of microcomputers 2 and a communication information storage unit 3 that stores communication data received by each microcomputer 2 and reception time information of the communication data. . In the present embodiment, the communication monitor device 1 includes three microcomputers 2A, 2B, and 2C, and the plurality of microcomputers 2 and the communication information storage unit 3 are mounted on a PCI board.

  The communication monitor device 1 includes a motherboard 4 as a management unit on which a CPU that executes a predetermined operating system is mounted. The motherboard 4 is connected to a communication information storage unit 3 and a PCI bus 5 mounted on a PCI board. It is connected. The management unit controls the entire communication monitor device 1 and the like.

  The communication information storage unit 3 includes a storage area such as a register for reading and storing communication data and reception time information, and associates a plurality of communication data output from each microcomputer 2 with the reception time information. , Stored in the storage areas at different addresses. In order to realize such a function, the communication information storage unit 3 is configured by, for example, an FPGA (Field Programmable Gate Array).

  The communication information storage unit 3 is connected to each microcomputer 2 via an A / D bus (address data bus) 6 composed of a plurality of address lines and data lines.

  Further, the communication information storage unit 3 includes a reference timer circuit 31. The reference timer circuit 31 is configured by a free-run timer that repeats timing at a preset period, and the free-run timer is configured by including, for example, a crystal oscillator.

  Each microcomputer 2 receives a communication data transmitted through each communication line SL (SL1 to SL6), and a time stamp process for giving reception time information to the communication data received by the reception unit 21 And a portion 22. Each microcomputer 2 includes a CPU, a ROM that stores a control program executed by the CPU, a RAM that is used as a working area, a peripheral circuit, and the like. The functions of the unit 22 and the like are realized by the CPU executing a control program.

  The receiving unit 21 is configured to generate a reception interrupt when receiving communication data transmitted via each communication line SL. The receiving unit 21 includes various registers such as a data register that stores received communication data and an interrupt register that stores various states in order to execute a reception interrupt.

  Each time stamp processing unit 22 is configured to read communication data received by the receiving unit 21 and to add reception time information to the communication data. That is, each time stamp processing unit 22 is configured to add reception time information to metadata such as a data format and a title constituting communication data.

  When adding the reception time information to the communication data, each time stamp processing unit 22 sets the value of the reference timer circuit 31 common to each microcomputer 2 acquired at the time of reading each communication data, at the time of receiving each communication data, and The reception time information is generated by performing correction based on the difference value of the value of the internal timer circuit 23 of each microcomputer 2 acquired at the time of reading.

  Specifically, in this embodiment, each microcomputer 2 has a local time information acquisition unit 24 that acquires the value of the internal timer circuit 23 and a reference that acquires the value of the reference timer circuit 31 common to the plurality of microcomputers 2. Each time stamp processing unit 22 from the reference time information acquired by the reference time information acquisition unit 25 at the time of reading communication data from the reception unit 21 and the reception unit 21 A value obtained by subtracting the difference value of the received local time information acquired by the local time information acquiring unit 24 at the time of reading communication data from is calculated as received time information.

  Here, like the reference timer circuit 31, the internal timer circuit 23 is configured by a free-run timer. The local time information acquisition unit 24 includes, for example, a register that stores the latest count value of the internal timer circuit 23. The reference time information acquisition unit 25 stores, for example, the latest count value of the reference timer circuit 31. It is composed of registers.

  Each time stamp processing unit 22 is stored in the local time information acquisition unit 24 at the time of reception by the reception unit 21 in order to realize the calculation of the reception time information and the addition of the calculated reception time information to the communication data. The count value stored in the latch circuit 220 is subtracted from the count value stored in the local time information acquisition unit 24 when the communication circuit data is read from the latch circuit 220 storing the received count value and the communication data. A subtractor 221, a subtracter 222 that subtracts the calculation result in the subtractor 221 from the count value stored in the reference time information acquisition unit 25 when reading out the communication data from the reception unit 21, and a subtracter 222 And a reception time information adding unit 223 for adding the calculation result to the communication data read from the receiving unit 21.

  The storage of the count value by the latch circuit 220 is executed under the control of hardware such as a peripheral circuit provided in the microcomputer 2 or firmware incorporated in the hardware when a reception interrupt occurs.

  The calculation of the reception time information by the subtracters 221 and 222 and the addition of the reception time information to the communication data by the reception time information adding unit 223 are executed by the CPU of the microcomputer 2 executing a control program, that is, software. This is executed when the communication data is read from the receiving unit 21 under the control of

  Here, the time when the communication data is read from the receiving unit 21 is the time after the start of the reading process by the software executed in response to the occurrence of the reception interrupt. For example, the reading process of the communication data from the receiving unit 21 is started. Or when a predetermined time elapses after the start of reading the communication data from the receiving unit 21, or immediately after the end of the reading process of the communication data from the receiving unit 21.

  Each time stamp processing unit 22 executes a process for unifying the count-up cycles of both timer circuits 23 and 31 to the same cycle when the count-up cycles of the internal timer circuit 23 and the reference timer circuit 31 are different. It is configured.

  This will be described in detail below. The time stamp processing unit 22 matches the count-up cycle of the timer circuit with high accuracy with the count-up cycle of the timer circuit with low accuracy.

  For example, when the count-up cycle of the internal timer circuit 23 is 125 (nsec) and the count-up cycle of the reference timer circuit 31 is 1 (μsec), the time stamp processing unit 22 counts the internal timer circuit 23 with high accuracy. The value is divided by 8 and rounded to a predetermined digit, and the count value of both timer circuits 23 and 31 is matched by matching with the count value of the low-precision reference timer circuit 31.

  As a specific example of unifying the count-up period to the same period, as shown in FIG. 10, the count-up period of the internal timer circuit 23 is 0.5 (μsec), and the count-up period of the reference timer circuit 31 is 1 (μsec). ), The count value of the internal timer circuit 23 at the time of reception is “4”, the count value of the internal timer circuit 23 at the time of data read processing is “8”, and the count value of the reference timer circuit 31 at the time of reception is “ 1 ”, when the count value of the reference timer circuit 31 at the time of data reading processing is“ 4 ”, the time stamp processing unit 22 divides the count value of the internal timer circuit 23 by 2, and the internal timer circuit at the time of reception The count value of 23 is “2”, and the count value of the internal timer circuit 23 at the time of data read processing is “4”.

  When the count value of the internal timer circuit 23 after division is compared with the count value of the reference timer circuit 31, at the time of reception, the count value of the internal timer circuit 23 is “2” and the count value of the reference timer circuit 31 is “1”. In the data read process, the count value of the internal timer circuit 23 is “4” and the count value of the reference timer circuit 31 is “4”. That is, in the case of the above-described method, the error that occurs can be suppressed to the count-up cycle of the timer circuit with low accuracy at the maximum.

  In addition, each microcomputer 2 has exclusive communication data output so that the communication data to which the reception time information is given in each time stamp processing unit 22 is not simultaneously output to the A / D bus 6. A switch circuit 26 is provided for selection. The selection of the output communication data by the switch circuit 26 is a configuration that can be switched by the instruction of the arbitration circuit described in the next paragraph, even if the configuration is such that each microcomputer 2 switches according to the reception order of each communication data. Also good.

  Further, the communication monitor device 1 prevents the communication data from being simultaneously output from the microcomputers 2 to the communication information storage unit 3, that is, a plurality of communication data collide on the A / D bus 6. So that the output order of the communication data is adjusted based on the input order to the receiving unit 21 and the like.

  Hereinafter, the reception time information generation processing by the communication monitoring apparatus 1 will be described based on the time chart of FIG. 7 and the flowchart of FIG.

  In the microcomputer 2A, the reception unit 211 receives the communication data D1 from the communication line SL1, and at the same time, the reception unit 212 receives the communication data D2 from the communication line SL2. In the microcomputer 2B, the reception unit 213 receives the communication data D2 from the communication line SL3. A case where the receiving unit 214 receives the communication data D4 from the communication line SL4 simultaneously with receiving the communication data D3 will be described. In the following description, the count-up cycle of the internal timer circuit 23 is 125 (nsec), and the count-up cycle of the reference timer circuit 31 is 1 (μsec).

  When receiving the communication data D1 and D2 respectively (S1), the receiving units 211 and 212 set the interrupt registers of the receiving units 211 and 212 at time B1, which is the count value of the internal timer circuit 23 when receiving the communication data D1 and D2. A reception interrupt is generated by turning on (S2), and the receiving units 213 and 214 receive the communication data D3 and D4 (S1), respectively, and the count value of the internal timer circuit 23 at the time of receiving the communication data D3 and D4 is received. A reception interrupt is generated by turning on the interrupt registers of the reception units 213 and 214 at a certain time C1 (S2).

  At this time, since the internal timer circuits 23 of the two microcomputers 2A and 2B are separate circuits and are not synchronized with each other, it is assumed that the microcomputers 2A and 2B received the communication data D1, D2, D3 and D4 at the same time. However, the time B1 and the time C1 are not necessarily the same time.

  When the reception units 211 and 212 generate a reception interrupt, the count value stored in the local time information acquisition unit 24 of the microcomputer 2A is stored in the latch circuit 220 of the microcomputer 2A (S3). Similarly, when the reception units 213 and 214 generate a reception interrupt, the count value stored in the local time information acquisition unit 24 of the microcomputer 2B is stored in the latch circuit 220 of the microcomputer 2B (S3). That is, the value of time B1 is stored in the latch circuit 220 of the microcomputer 2A, and the value of time C1 is stored in the latch circuit 220 of the microcomputer 2B.

  Then, under the control of software corresponding to the reception interrupt, the microcomputer 2A starts the communication data D1 reading process, and similarly, the microcomputer 2B starts the communication data D3 reading process (S4). Note that the reading process of the communication data D2 and D4 is suspended until the reading process of the communication data D1 and D3 is completed.

  In each of the microcomputers 2A and 2B, the count value (time) of the internal timer circuit 23 stored in the local time information acquisition unit 24 in the subtractor 221 at the times B2 and C2 when the communication data D1 and D3 are read. B2 and C2) are subtracted from the count values (time B1 and C1) stored in the latch circuit 220 (S5), and the timer stamp processing unit 22 counts up the internal timer circuit 23 and the reference timer circuit 31. In order to unify the cycle, an operation for dividing the result of the operation (B2-B1, C2-C1) by 8 is executed (S6), and the count stored in the reference time information acquisition unit 25 in the subtractor 222. The calculation result ((B2-B1) / 8, (C2-C1) / 8) in the timer stamp processing unit 22 is not subtracted from the value (time A2). Operation is performed (S7).

  In FIG. 7, the time A2 and the times B2 and C2 are displayed as if they were the same time, but the reference timer circuit 31 and the internal timer circuit 23 are separate circuits and are not synchronized with each other. Therefore, time A2 and time B2 and C2 are not necessarily the same time.

  Thereafter, in the reception time information adding unit 223 of each microcomputer 2A, 2B, the calculation results (A2- (B2-B1) / 8, A2- (C2-C1) / 8) are stored in the communication information from the receiving unit 21. The communication data D1 and D3 output to the unit 3 are added to the communication data D1 and D3, respectively (S8), and the communication data D1 and D3 read processing ends.

  Subsequently, under the control of the software, the microcomputer 2A starts the reading process of the communication data D2 and the microcomputer 2B starts the reading process of the communication data D4 with the end of the reading process of the communication data D1 and D3 as a trigger. (S9).

  In each of the microcomputers 2A and 2B, the count value (time) of the internal timer circuit 23 stored in the local time information acquisition unit 24 in the subtracter 221 at the times B3 and C3 when reading the communication data D2 and D4. B3, C3) is subtracted from the count value (time B1, C1) stored in the latch circuit 220 (S10), and the timer stamp processing unit 22 counts up the internal timer circuit 23 and the reference timer circuit 31. In order to unify the cycle, an operation of dividing the result of the operation (B3-B1, C3-C1) by 8 is executed (S11), and the count stored in the reference time information acquisition unit 25 in the subtractor 222 An operation for subtracting the operation result ((B3-B1) / 8, (C3-C1) / 8) in the subtractor 221 from the value (time A3). The line (S12). As described above, the time A3 and the times B3 and C3 are not necessarily the same time.

  Thereafter, in the reception time information assigning unit 223 of each of the microcomputers 2A and 2B, the calculation results (A3- (B3-B1) / 8, A3- (C3-C1) / 8) are stored in the communication information from the receiving unit 21. It is added to the communication data D2 and D4 output to the unit 3 (S13), and the reading process of the communication data D2 and D4 is completed.

  According to the above-described configuration, the reception time information is generated based on the count value of the reference timer circuit 31 used in common for both the microcomputers 2A and 2B, so that the internal timer circuit 23 of both the microcomputers 2A and 2B Can eliminate time lag due to asynchronous.

  In addition, when another interrupt process or output of communication data from another microcomputer 2 is executed between the reception interrupt and the communication data read process, and the communication data read process is suspended, There is a possibility that the time until the communication data reading process is delayed. Also, the time until the read process varies depending on the presence or absence of other interrupt processes, that is, when another interrupt process occurs, the time until the read process is longer than when no other interrupt process occurs. There is a risk of this. As a result, these delays and variations become errors in the reception time information given to the communication data.

  However, according to the above-described configuration, the internal timer circuits of the microcomputers 2A and 2B acquired at the time of reception and reading of each communication data from the count value A3 of the reference timer circuit 31 regardless of the presence or absence of other interrupt processing. By performing correction by subtracting B2-B1 and C2-C1 which are the difference values of the values of 23, these delays and variations are corrected, so that the occurrence of errors can be reduced. Even if there is a difference between “B1” and “C1” and “B2” and “C2” due to the separate internal timer circuit 23, the difference “B2-B1” and “C2-C1” are substantially the same. This is because it becomes a value.

  As described above, the communication monitoring method according to the present invention includes a plurality of microcomputers 2 that receive communication data transmitted via each communication line, and gives reception time information to the communication data received by each microcomputer 2. In the communication monitoring method, each microcomputer 2 uses the value of the common reference timer circuit 31 acquired at the time of reading each communication data as the internal timer circuit of each microcomputer 2 acquired at the time of receiving and reading each communication data. This is a method of generating reception time information by correcting based on a difference value of 23 values.

  Hereinafter, another embodiment will be described. As shown by the broken line in FIG. 6 and as shown in FIG. 8A, the communication monitoring device 1 is connected to each communication line SL that is input to and output from a communication gateway G that connects a plurality of networks of different systems. May be configured to include an evaluation unit 7 that is connected to each reception unit 21 and evaluates the connection operation of the communication gateway G based on each communication data and reception time information stored in the communication information storage unit 3.

  As shown in FIG. 8B, the communication gateway G is configured to mutually connect a plurality of networks having different protocols. For example, the communication gateway G includes a plurality of protocol conversion processing units 81 (811 to 81i) and gateway processing. A portion 82 and the like are provided.

  The protocol conversion unit 81 outputs communication data to the corresponding network N using a protocol unique to the network N, and transmits the communication data input from the network N to the destination network N added to the communication data. Is converted into intermediate data that specifies the transmission destination network N and output.

  The gateway processing unit 82 is output from each protocol conversion processing unit 81 based on a transmission / reception route information table 83 in which a plurality of intermediate data and an address indicating the transmission destination network N corresponding to each intermediate data are stored in advance. The intermediate data is relayed and output to the protocol conversion processing unit 81 corresponding to the destination network N.

  The evaluation unit 7 includes, for example, a general-purpose computer that is installed with an application program that operates under a predetermined operating system and includes a display unit and input / output devices such as a keyboard and a mouse.

  Then, each communication data transmitted through each communication line SL and received by each receiving unit 21 of each microcomputer 2 is fetched together with the reception time information given by the time stamp processing unit 22, and these communication data and reception time are taken. Based on the information, the communication gateway 8 is evaluated.

  For example, as shown in FIG. 8A, communication data output from one electronic control device A is input to another electronic control device E via the communication line SL1, the communication gateway G, and the communication line SL5. The communication data being transmitted through the communication line SL1 and the communication data being transmitted through the communication line SL5 are captured by the receiving units 21 of the microcomputers 2A and 2C of the communication monitor device 1, and reception time information is given to each communication data. And output to the evaluation unit 7.

  The evaluation unit 7 evaluates whether or not the format of the communication data acquired from the communication line SL1 matches the protocol of the network to which the electronic control device A belongs, and the format of the communication data acquired from the communication line SL5 is electronic. It is evaluated whether or not it matches the protocol of the network to which the control device E belongs. The evaluation unit 7 determines that the communication data is transmitted without any problem when the format of the communication data matches the protocol.

  Further, the evaluation unit 7 calculates a difference between the reception time information of the communication data acquired from the communication line SL1 and the reception time information of the communication data acquired from the communication line SL5, and the difference is calculated in advance for the communication gateway 8. Evaluate whether it is longer than the set connection switching time. When the difference is smaller than the connection switching time, the evaluation unit 7 determines that the switching operation by the communication gateway 8 is executed without any problem.

  As described above, the communication monitor device 1 may be configured as a communication gateway evaluation device as described below.

  That is, the communication gateway evaluation apparatus receives the communication data transmitted via the communication line input / output to / from the communication gateway G that interconnects a plurality of networks of different systems, and the reception unit 21 receives the communication data. Communication information for storing a plurality of microcomputers 2 each having a time stamp processing unit 22 for giving reception time information to the received communication data, communication data received by each microcomputer 2, and reception time information of the communication data A communication gateway evaluation device including a storage unit 3 and an evaluation unit 7 that evaluates a connection operation of the communication gateway G based on each communication data and reception time information stored in the communication information storage unit 3. The stamp processing unit 22 is a reference type common to each microcomputer 2 acquired when reading each communication data. The value of the circuit 31 is corrected based on the difference value of the value of the internal timer circuit 23 of each microcomputer 2 acquired at the time of receiving and reading each communication data, and the reception time information is generated. Whether the connection operation by the communication gateway G is executed within a preset connection switching time based on the communication data and the reception time information, or each communication data is converted based on a preset conversion rule It is configured to evaluate whether or not.

  In the above-described embodiment, the configuration in which the reference timer circuit 31 is provided in the communication information storage unit 3 has been described. However, the configuration is not limited to such a configuration. For example, the communication monitor device 1 includes the microcomputer 2 and the communication information storage unit. 3 and an internal timer circuit 23 provided in one of a plurality of microcomputers 2 is used as a reference timer circuit, and the other microcomputers 2 are connected to the internal timer circuit. A configuration may be used in which the value of the circuit 23 is used as the value of the reference timer circuit to generate reception time information.

  In the above-described embodiment, the configuration in which the microcomputer 2 includes the receiving unit 21 that receives communication data transmitted via each communication line SL has been described. However, the microcomputer 2 is configured via each communication line SL. The structure provided with the transmission part which transmits the communication data transmitted may be sufficient.

  For example, the microcomputer 2A is configured to include a transmission unit instead of the reception unit 212 in FIG. 6, and the communication monitoring device 1 communicates from the transmission unit after giving the transmission time information by the time stamp processing unit 22. The configuration may be such that communication data is output to the line SL2. When the communication monitor device 1 has such a configuration, the communication monitor device 1 takes a time from data transmission to the electronic control device via the transmission unit to data return from the electronic control device via the reception unit. Can be measured.

  In the above-described embodiment, the communication monitor device 1 includes the three microcomputers 2A, 2B, and 2C, and each microcomputer 2 includes the two reception units 21. The number of microcomputers 2 included in the device 1 is not limited to three, and the number of receiving units 21 included in each microcomputer 2 is not limited to two. For example, the communication monitor device 1 may include four microcomputers 2 and each microcomputer 2 may include three receiving units 21.

  In the above-described embodiment, the configuration in which the inspection target is the communication gateway G has been described. However, the inspection target is not limited to the communication gateway G, and for example, an electronic control device that controls the engine may be the inspection target. In this case, for example, the communication monitor device 1 transmits data to the electronic control device that controls the engine, and measures the time until the data is returned from the electronic control device to the communication monitor device 1. Then, the electronic control device is inspected.

  In the above-described embodiment, the communication monitoring device 1 (communication gateway evaluation device) according to the present invention monitors a communication line connected to an electronic control device that controls an engine or the like, that is, communication data transmitted through an in-vehicle network. As described above, what the communication monitoring device 1 monitors is not limited to communication data transmitted through the in-vehicle network. For example, the communication monitoring apparatus 1 may be applied to a network mounted on an aircraft, an air conditioning system, or the like, and may be configured to monitor communication data transmitted through the network.

  Note that the above-described embodiment is merely an example of the present invention, and it is needless to say that the specific configuration and the like of each block can be changed and designed as appropriate within the scope of the effects of the present invention.

Explanatory drawing about connection of communication monitoring device Block diagram of a conventional communication monitoring device using an internal timer circuit 2A illustrates the reception of communication data by the microcomputer 201 of the communication monitoring apparatus having the configuration shown in FIG. 2, and FIG. 2B illustrates the reception of communication data by the microcomputer 202 of the communication monitoring apparatus having the configuration of FIG. Time chart for Block diagram of a conventional communication monitoring device using a reference timer circuit (A) shows the connection between the electronic control device and the communication gateway of the communication monitoring device, and (b) is an explanatory diagram showing a configuration in which the electronic control device is realized by a simulation device in FIG. Block diagram of a communication monitoring device according to the present invention. 6A illustrates the reception of communication data by the microcomputer 2A of the communication monitor apparatus having the configuration of FIG. 6, and FIG. 6B illustrates the reception of communication data by the microcomputer 2B of the communication monitor apparatus having the configuration of FIG. Time chart for (A) shows connection with the electronic control unit and communication gateway of the communication monitoring apparatus provided with the evaluation part, (b) is an explanatory view showing the block configuration of the communication gateway Flowchart for explaining reception of communication data by the communication monitor apparatus having the configuration of FIG. Illustration of unifying the count-up cycle into the same cycle

Explanation of symbols

1: Communication monitoring device 2: Microcomputer 3: Communication information storage unit 7: Evaluation unit 21: Reception unit 22: Time stamp processing unit 23: Internal timer circuit 24: Local time information acquisition unit 25: Reference time information acquisition unit 31: Reference timer circuit G: Communication gateway SL: Communication line

Claims (5)

A plurality of microcomputers each including a receiving unit that receives communication data transmitted via each communication line, and a time stamp processing unit that adds reception time information to the communication data received by the receiving unit, A communication monitoring device comprising a communication information storage unit for storing communication data received by a computer and reception time information of the communication data,
Each time stamp processing unit uses a reference timer circuit value common to each microcomputer acquired at the time of reading each communication data, and a difference between values of internal timer circuits of each microcomputer acquired at the time of reception and reading of each communication data. A communication monitoring device, wherein the reception time information is generated by correcting based on a value. A receiving unit that generates a reception interrupt when receiving communication data transmitted via each communication line; and a time stamp processing unit that reads out the communication data received by the receiving unit and gives reception time information to the communication data; A communication monitoring device comprising a plurality of microcomputers, communication data received by each microcomputer, and a communication information storage unit that stores reception time information of the communication data,
Each microcomputer includes a local time information acquisition unit that acquires a value of an internal timer circuit, and a reference time information acquisition unit that acquires a value of a reference timer circuit common to a plurality of microcomputers.
Each time stamp processing unit, based on the reference time information acquired by the reference time information acquisition unit at the time of reading communication data from the reception unit, the local time at the time of the reception interrupt occurrence and at the time of reading communication data from the reception unit A communication monitoring apparatus characterized in that a value obtained by subtracting a difference value of reception local time information acquired by each time information acquisition unit is calculated as the reception time information.   Each communication line input / output to / from a communication gateway device connecting a plurality of networks is connected to each reception unit, and the communication gateway device is evaluated based on each communication data and reception time information stored in the communication information storage unit The communication monitoring apparatus according to claim 1, further comprising an evaluation unit that performs the evaluation. A receiving unit that receives communication data transmitted via a communication line that is input to and output from a communication gateway device that connects a plurality of networks, and a time stamp process that adds reception time information to the communication data received by the receiving unit A plurality of microcomputers, a communication information storage unit that stores communication data received by each microcomputer and reception time information of the communication data, each communication data stored in the communication information storage unit, A communication gateway evaluation device comprising an evaluation unit for evaluating the communication gateway device based on reception time information,
Each time stamp processing unit uses a reference timer circuit value common to each microcomputer acquired at the time of reading each communication data, and a difference between values of internal timer circuits of each microcomputer acquired at the time of reception and reading of each communication data. The reception time information is generated by correcting based on the value,
The said evaluation part evaluates the said communication gateway apparatus based on each communication data and reception time information, The communication gateway evaluation apparatus characterized by the above-mentioned. A communication monitoring method comprising a plurality of microcomputers for receiving communication data transmitted via each communication line, and adding reception time information to communication data received by each microcomputer,
Each microcomputer corrects the value of the common reference timer circuit acquired at the time of reading each communication data based on the difference value of the value of the internal timer circuit of each microcomputer acquired at the time of receiving and reading each communication data. A communication monitoring method for generating the reception time information.

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