Communication device, communication system, and fault omen diagnosis method

Abstract

A communication device for transmitting a data signal is provided with a setting value data variation diagnosis unit. The setting value data variation diagnosis unit uses first setting value data for adjusting a transmission waveform when transmitting and receiving a data signal to and from an external device via a transmission line, and second setting value data for adjusting a transmission waveform when looping back a data signal between a transmission circuit and a reception circuit in a transmission device, and determines the variation of the data signal based on a predetermined determination condition. The communication device determines a change in the first setting value data when transmitting and receiving a data signal to and from the external device via the transmission line and a change in the second setting value data when looping back the data signal between the transmission circuit and the reception circuit, and diagnoses a fault indication of the communication device and the transmission line on the basis of the determination results.

Description

Technical Field

[0001] The present invention relates to a communication device, a communication system, and a predicted failure sign diagnosis method having a function of performing a predicted failure sign diagnosis in data communication via an in-vehicle network, for example. Background Art

[0002] In recent years, data communication has become indispensable in the foundation of industry and life, and it is hoped that the signs of failure can be detected before the communication device fails. For example, with the popularization of autonomous driving and car-sharing services, it is difficult to ensure the long-term reliability of semiconductor components installed in automobiles if the operation rate of automobiles increases significantly. Therefore, it is believed that maintaining the functions of semiconductor components by replacing parts will become the mainstream in the future. Semiconductors used in communication devices that communicate data with on-board sensors and cameras are closely related to safety control, so it is necessary to establish a diagnostic method that focuses on the diagnosis of failure signs.

[0003] Patent Document 1 discloses a method of diagnosing a sign of failure by comparing setting value data for adjusting a transmission waveform during communication with diagnostic reference information. Prior art literature Patent Literature

[0004] Patent Document 1: Japanese Patent Application Publication No. 2017-129969 Summary of the invention Problem that the invention aims to solve

[0005] Using the technology of Patent Document 1, for example, when a fault sign is detected in a communication path where a first communication device and a second communication device are connected via a transmission line, it is possible to determine that the diagnosed communication path is in a fault sign state. However, it is impossible to determine whether the location of the fault sign is the first communication device, the second communication device, or the transmission line. Therefore, it is necessary to spend maintenance man-hours to determine the actual location of the fault sign, and when the location of the fault sign cannot be determined, more than necessary parts or communication devices will be replaced preventively for suspicious parts or communication devices, thereby increasing costs.

[0006] In view of the above situation, a method is desired that can at least determine whether a communication device to be diagnosed is in a state of predicted failure. Technical means of solving problems

[0007] In order to solve the above-mentioned problem, a communication device according to one embodiment of the present invention is a communication device for transmitting a data signal, comprising: a transmitting circuit for transmitting a data signal; a receiving circuit for receiving a data signal; and a set value data change diagnosis unit, which uses first set value data for adjusting a transmission waveform when transmitting and receiving a data signal with an external device via a transmission line, and second set value data for adjusting a transmission waveform when looping back the data signal between the transmitting circuit and the receiving circuit, and determines, according to specified judgment conditions, changes in the first set value data when transmitting and receiving a data signal with an external device via a transmission line, and changes in the second set value data when looping back the data signal between the transmitting circuit and the receiving circuit, and diagnoses signs of failure of the communication device and the transmission line based on the judgment results. Effects of the Invention

[0008] According to at least one aspect of the present invention, by adding failure sign diagnosis during loopback to diagnosis during transmission and reception with an external device via a transmission line, a communication device can perform self-diagnosis and determine whether the communication device to be diagnosed is in a failure sign state. The other objects, structures, and effects than those described above will become clear from the following description of the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a block diagram showing an example of the internal configuration of a communication device constituting the communication system according to the first embodiment of the present invention. Figure 2 This is a diagram showing an example of temporal variation of setting value data for transmission waveform adjustment according to the first embodiment of the present invention. Figure 3 This is a diagram showing a table in which the predicted failure-evidence diagnosis results in the communication device alone are classified into different cases according to the first embodiment of the present invention. Figure 4 This is a diagram showing a table in which predicted failure-evidence diagnosis results in two communication devices are classified into different cases according to the first embodiment of the present invention. Figure 5 This is a block diagram showing an example of the internal configuration when the communication device according to the first embodiment of the present invention is provided with a temperature detection unit. Figure 6 This is a block diagram showing an example of the internal configuration when a power supply voltage detection unit is provided in the communication device according to the first embodiment of the present invention. Figure 7 This is a diagram showing an example of a configuration in which information on predicted-failure-evidence diagnosis results is collected in a host device and a predicted-failure-evidence location is identified by the host device in the communication system according to the first embodiment of the present invention. Figure 8This is a diagram showing an example of a configuration in which a predicted failure sign location is identified by a communication device without using a host device in a communication system according to a second embodiment of the present invention. Fig. 9 This is a diagram showing an example of a configuration in which a determination threshold used in predicted failure indication diagnosis of a communication device is changed in accordance with an instruction from an external device in a communication system according to a third embodiment of the present invention. Fig.10 This is a diagram showing an example of a configuration in which an instruction from an external device is transmitted and received between two communication devices by wireless communication in a communication system according to a third embodiment of the present invention. Fig.11 This is a block diagram showing a hardware configuration example of a communication device, a microcomputer, and a computer included in a server according to the first embodiment of the present invention. DETAILED DESCRIPTION

[0010] Hereinafter, examples of methods for implementing the present invention (hereinafter referred to as "implementation methods") are described with reference to the accompanying drawings. In this specification and the accompanying drawings, the same components or components having substantially the same functions are marked with the same symbols and repeated descriptions are omitted. In addition, when there are multiple components having the same or similar functions, different subscripts are sometimes added to the same symbols for description. In addition, when there is no need to distinguish these multiple components, the subscripts are sometimes omitted for description.

[0011] <First embodiment> First, a communication device according to a first embodiment of the present invention and a communication system using the communication device will be described. Figure 1 1 is a block diagram showing an example of the internal structure of a communication device constituting the communication system according to the first embodiment. Figure 1 In the example shown, the communication device 1 and the communication device 2 are connected via a transmission line 10. In the case of in-vehicle Ethernet (registered trademark), the transmission line 10 is a set of twisted pair cables (differential transmission line). Full-duplex communication can be performed between the communication device 1 and the communication device 2 using the twisted pair cables. For example, the communication device 1 and the communication device 2 are used as an in-vehicle Ethernet switch.

[0012] [Configuration of Communication Device 1] In the communication device 1, the transmission circuit is composed of a transmission processing circuit 101, an emphasis circuit 102, and a transmission output circuit 103, and the reception circuit is composed of a reception input circuit 104, an equalizer circuit 105, an error detection unit 106, and a reception processing circuit 107. In addition, the communication device 1 includes an input / output unit 108 and a setting value data change diagnosis unit 109, which diagnoses the change of the setting value data for transmission waveform adjustment, and the details will be described later.

[0013] The transmission processing circuit 101 converts data (e.g., IP packets) output from the input / output unit 108 into a signal suitable for transmission (referred to as a "data signal"), and outputs the data signal to the emphasis circuit 102 via the signal line 11. In the figure, the transmission processing circuit 101 is indicated as "TX".

[0014] The emphasis circuit 102 amplifies the high frequency band of the data signal input from the transmission processing circuit 101 according to the attenuation characteristics at high frequencies inherent in the transmission path, and outputs it to the transmission output circuit 103. As a result, the frequency characteristics of the data signal received by the communication device 2 on the receiving side are improved. In addition, the emphasis circuit 102 outputs the set value data 1 for adjusting the transmission waveform described later (the value obtained by indexing the value of the tap coefficient for adjusting the transmission waveform) to the set value data change diagnosis unit 109 via the signal line 12. Generally, the emphasis circuit 102 is realized by using a compensation circuit such as a frequency filter that is adjusted in a manner to optimize the frequency characteristics of the data signal.

[0015] The transmission output circuit 103 amplifies the data signal input from the emphasis circuit 102 at a preset gain, and outputs the data signal to the input / output unit 108 via the signal line 13 .

[0016] The input / output unit 108 performs a process of outputting the data signal input from the transmission output circuit 103 to the transmission line 10 (solid line). In addition, the data signal is input from the communication device 2 to the input / output unit 108 via the transmission line 10 (dashed line). Furthermore, the input / output unit 108 outputs the data signal input from the transmission output circuit 103 during loopback to the reception input circuit 104 via the signal line 14 (double-dashed line). Similarly, in the communication device 2, the input / output unit 208 outputs the data signal input from the transmission output circuit 203 during loopback to the reception input circuit 204 via the signal line 24 (dotted line).

[0017] The reception input circuit 104 amplifies the data signal input from the input / output unit 108 at a preset gain, and outputs the data signal to the equalizer circuit 105 .

[0018] After receiving the data signal from the receiving input circuit 104, the equalizer circuit 105 adjusts the frequency characteristics of the data signal for the purpose of restoring the signal waveform that has changed due to the characteristics of the transmission path or minimizing the change, and outputs the data signal to the error detection unit 106. In addition, the equalizer circuit 105 outputs the set value data 2 (the value of the tap coefficient for adjusting the transmission waveform) for transmission waveform adjustment described later to the set value data change diagnosis unit 109 via the signal line 15. The equalizer circuit 105 is implemented by using a compensation circuit such as a frequency filter that is adjusted in a manner to optimize the frequency characteristics of the data signal. In most cases, the high-frequency band is amplified for the signal sent from the transmission line for the purpose of enhancing the lost high-frequency component.

[0019] The error detection unit 106 compares the data signal input from the equalizer circuit 105 with a preset data signal to detect an error, and outputs the error detection result together with the data signal to the reception processing circuit 107 .

[0020] The reception processing circuit 107 receives the data signal and the error detection result, and performs processing to convert the data signal into data suitable for use in a subsequent processing block or device (not shown). In the figure, the reception processing circuit 107 is indicated as "RX".

[0021] The setting value data change diagnostic unit 109 monitors the changes of the setting value data 1 for transmission waveform adjustment obtained from the emphasis circuit 102 and the setting value data 2 for transmission waveform adjustment obtained from the equalizer circuit 105, and diagnoses the failure signs of the communication device and the transmission line. The setting value data change diagnostic unit 109 outputs the diagnosis result of the failure sign to the device outside the communication device 1 via the signal line 16.

[0022] [Configuration of Communication Device 2] In the communication device 2, the transmission circuit is composed of a transmission processing circuit 201, an emphasis circuit 202, and a transmission output circuit 203, and the reception circuit is composed of a reception input circuit 204, an equalizer circuit 205, an error detection unit 206, and a reception processing circuit 207. In addition, the communication device 2 includes an input / output unit 208 and a set value data change diagnosis unit 209, and the details of the set value data change diagnosis unit 209 are described below.

[0023] The transmission processing circuit 201, the emphasis circuit 202, and the transmission output circuit 203 constituting the transmission circuit are the same as the transmission processing circuit 101, the emphasis circuit 102, and the transmission output circuit 103 of the communication device 1. In addition, the reception input circuit 204, the equalizer circuit 205, the error detection unit 206, and the reception processing circuit 207 constituting the reception circuit are the same as the reception input circuit 104, the equalizer circuit 105, the error detection unit 106, and the reception processing circuit 107 of the communication device 1. In addition, the input / output unit 208 and the set value data change diagnosis unit 209 are the same as the input / output unit 108 and the set value data change diagnosis unit 109 of the communication device 1. The description of these processing blocks of the communication device 2 is omitted. In addition, the signal lines 21 to 26 correspond to the signal lines 11 to 16 of the communication device 1.

[0024] When transmitting and receiving data signals, communication devices 1 and 2 adjust the transmission waveform because they are affected by the frequency characteristics of transmission line 10. The circuits that perform this adjustment function are emphasis circuits 102 and 202 on the transmission side and equalizer circuits 105 and 205 on the reception side.

[0025] For example, the emphasis circuits 102 and 202 are, for example, finite impulse response (FIR) type digital filters (frequency filters). In a FIR type digital filter (hereinafter referred to as "FIR filter"), for example, when the number of taps of the transfer function is 3, the transmission waveform can be adjusted using 3 tap coefficients. Hereinafter, the tap coefficients are simply referred to as "coefficients".

[0026] The equalizer circuits 105 and 205 are, for example, decision feedback equalizers (DFE) using digital filters (frequency filters). In DFE, for example, when the number of taps of a transfer function is three, the transmission waveform can be adjusted using three tap coefficients.

[0027] In the emphasis circuits 102 and 202 and the equalizer circuits 105 and 205, the values ​​of the tap coefficients for adjusting the transmission waveform are indexed and referred to as "transmission waveform adjustment setting value data". However, "transmission waveform adjustment setting value data" is sometimes referred to simply as "setting value data". In the present embodiment, at least a change in either the emphasis circuit setting value data or the equalizer circuit setting value data is monitored to detect a sign of a failure.

[0028] Since both FIR filters and DFE are digital filters, an example of FIR filters is described here. The transfer function formula of the FIR filter is H(z)=a0+(a1×Z -1 )+(a2×Z -2 ) indicates that the three coefficients in the formula are a0, a1, and a2. For example, for each of the values ​​of the three coefficients a0, a1, and a2, the ratio of the change from the value of the initial state is calculated, and the value after indexing using the maximum value among them is used as the setting value data for transmission waveform adjustment.

[0029] For example, the values ​​in the initial state are "a0 = -0.20, a1 = +0.70, a2 = -0.10", and the subsequent state is "a0 = -0.30, a1 = +0.90, a2 = -0.10". In this case, the ratio of change from the initial state value is a0 = -50.0 [%], a1 = +28.6 [%], a2 = 0.0 [%].

[0030] The absolute value of the ratio of change from the value of the initial state is the largest at -50.0[%] of the coefficient a0, and the maximum value is 50[%]. The indexed value in this case is -50. Here, as an example, the percentage value is standardized to 0 to 100. The setting value data for transmission waveform adjustment (the value after indexing the value of the tap coefficient for adjusting the transmission waveform) tends to change more from the value of the initial state as the communication devices 1, 2 and the transmission line 10 deteriorate. Therefore, in the setting value data change diagnosis unit 109, by monitoring the change of the setting value data for transmission waveform adjustment, it is possible to diagnose a sign of a fault.

[0031] In the above example, the maximum value of the ratio of changes in the three coefficients is focused on, but each of the three coefficients may be converted into an index and the failure sign diagnosis may be performed separately. Alternatively, the permissible range of the three coefficients may be determined, and the minimum value of the three coefficients may be used as an indexed value for the tolerance up to the permissible range, or the three coefficients may be used as indexed values ​​respectively. In addition, among the three coefficients, a0 and a2 generate an undershoot waveform and play an important role in adjusting the transmission waveform, so the coefficients can also be weighted for indexing. For example, in the above example, in the case of "a0 = -0.2" → "a0 = -0.3", if the weight of the coefficient is 1.2 times, the ratio of the change is -50[%] → -60[%]. On the other hand, when the allowable range is determined and the margin is indexed, it is also possible to consider reducing the margin to 0.8 times. As described in Patent Document 1, it is also possible to consider the case of only paying attention to the changes in coefficients a0 and a2.

[0032] In addition, the above-mentioned FIR filter and DFE are examples of an emphasis circuit and an equalizer circuit for adjusting the transmission waveform, and are not limited to this circuit method, and also include analog signal processing circuits, etc. In addition, the number of taps is not limited to 3, and when the number of taps is N, the transmission waveform can be adjusted with N coefficients.

[0033] Usually, the setting value data for adjusting the transmission waveform is determined before the data signal is transmitted or received. For example, the setting value data for adjusting the transmission waveform is determined by repeating transmission and reception in a predetermined signal pattern between the communication device 1 and the communication device 2 so as to achieve the optimal condition for the error in the error detection unit 106 or 206 to be zero. A method for diagnosing a failure sign of a communication path using the setting value data for adjusting the transmission waveform during normal transmission and reception is known in Patent Document 1.

[0034] The present invention uses setting value data 1 (referred to as "setting value data 1" for distinction) for adjusting the transmission waveform during normal transmission and reception and setting value data 2 (referred to as "setting value data 2" for distinction from setting value data 1) for adjusting the transmission waveform during loopback from the transmission circuit to the reception circuit in the same communication device to perform fault sign diagnosis. In the present invention, in addition to being able to self-diagnose the normality and abnormality of the communication device itself, by using the diagnosis results of transmission and reception between the communication device 1 and the communication device 2, the fault sign location (communication device 1 or communication device 2 or transmission line 10) can be determined.

[0035] For example, in the fault sign diagnosis during normal transmission and reception, when it is determined that there is a fault sign in "communication device 2 sends" → "transmission line 10" → "communication device 1 receives", it can be understood that there is an abnormality in the communication path, but the location of the fault sign cannot be determined. Therefore, in the present invention, by adding the fault sign diagnosis during loopback, it is possible to obtain information on the self-diagnosis results for communication device 1 and communication device 2 respectively, so that the location of the fault sign can be determined. If there is a response of normal reception from the communication device at the transmission destination (for example, communication device 1), it can be confirmed that the communication is normal. The confirmation of the presence or absence of a response from the communication counterpart is performed by the communication device that sent the data signal or the upper device described later.

[0036] The signal path when a loop is performed within the same communication device, for example in the case of communication device 1, is "transmission processing circuit 101" → "emphasis circuit 102" → "transmission output circuit 103" → "signal line 13" → "input and output unit 108" → "signal line 14" → "reception input circuit 104" → "equalizer circuit 105" → "error detection unit 106".

[0037] As in normal transmission and reception, the setting value data 2 for transmission waveform adjustment is determined so as to achieve the optimum condition for zero error in the error detection unit 106 of the communication device 1. The same is true for the communication device 2, so the description thereof is omitted.

[0038] During loopback, since the communication path does not include the transmission line 10, the transmission waveform has less distortion. Therefore, it is more effective to adjust the transmission waveform in the emphasis circuit 102 and the equalizer circuit 105 under setting conditions different from those during normal transmission and reception. For example, in the setting of the tap coefficient of the transfer function in the emphasis circuit 102, the setting is performed in such a way that the signal amplitude becomes smaller. Alternatively, the gain of the entire signal in the transmission output circuit 103 and the gain of the entire signal in the reception input circuit 104 are adjusted to a setting that reduces the signal amplitude.

[0039] In addition, regarding the signal pattern when investigating the optimal conditions, it is considered that a diagnostic pattern prone to error, such as only one Hi level in a continuous Lo level, and only one Lo level in a continuous Hi level, is suitable for capturing changes as a fault sign diagnosis. In a diagnostic pattern prone to error, an error is easily detected by the error detection unit 106. In addition, as a diagnostic pattern prone to error, a diagnostic pattern in which the frequency of the signal is increased and the interval of the time axis is shortened can also be considered.

[0040] In addition, although not shown in the figure in this embodiment, in the case of a configuration in which full-duplex communication is performed through one transmission line (for example, using different frequency bands), an echo cancellation circuit (not shown) is mounted to remove the transmission signal included in the reception signal. The echo cancellation function is activated during loopback, and when the looped signal is removed, it is necessary to take measures such as disabling the echo cancellation function. For example, the circuit for disabling the echo cancellation function is provided between the input / output unit 108 and the reception input circuit 104, at least one stage before the equalizer circuit 105.

[0041] In addition, when looping back in the communication device 1, it may be affected by reflection of the electric signal from the connected transmission line 10 or the data signal from the communication device 2. In such a case, for example, a method of providing a function of disconnecting the transmission line 10 by a switch circuit or the like in the input / output unit 108 and performing a method of predictive diagnosis of a fault during looping back in a state where the transmission line 10 is disconnected may be considered.

[0042] In addition, the failure sign diagnosis needs to be performed at a time that does not interfere with normal communication. For example, the setting value data change diagnosis unit 109 preferably performs the failure sign diagnosis at the start-up (communication training) or end of the communication device.

[0043] The transmission waveform adjustment set value data variation diagnosis section 109 performs diagnosis of a failure sign using the transmission waveform adjustment set value data 1 and set value data 2 indexed with the tap coefficients of the transfer functions of the emphasis circuit 102 and the equalizer circuit 105 .

[0044] Next, use Figure 2 The following describes the temporal changes in the set value data of the transmission waveform adjustment. Figure 2 This is a diagram showing an example of temporal variation of setting value data for transmission waveform adjustment according to the present embodiment. Figure 2 The horizontal axis represents time and the vertical axis represents the set value data for the transmission waveform adjustment, which is an example of a case where determination is performed using a plurality of threshold values.

[0045] The setting value data change diagnosis unit 109 determines the change of the setting value data (failure sign) based on the relationship between the setting value data adjusted by the transmission waveform and the threshold values ​​(TH-U1, TH-U2, TH-U3, TH-D1, TH-D2, TH-D3). The magnitude relationship of the upper threshold value is TH-U1 < TH-U2 < TH-U3, and the magnitude relationship of the lower threshold value is TH-D1 > TH-D2 > TH-D3.

[0046] In this example, the value of the set value data of the transmission waveform adjustment changes upward with the passage of time. Here, as the simplest diagnostic method, when it is determined as a fault sign when it exceeds the upper threshold value TH-U3, it can be considered that it is simply determined as a fault sign when the value of the set value data of the transmission waveform adjustment exceeds the threshold value TH-U3. In addition, when the value of the set value data of the transmission waveform adjustment is lower than the lower threshold value TH-D3, it is also determined as a fault sign.

[0047] In addition, the time until the fault sign (here, threshold TH-U3) is predicted based on the time when the threshold TH-U1 is exceeded or the time when the threshold TH-U2 is exceeded. That is, the time when the set value data adjusted by the transmission waveform reaches the threshold TH-U3 can be known from the time when the set value data exceeds the threshold TH-U1 to the threshold TH-U2. In addition, the state of the fault sign (the development speed of component degradation) can also be estimated based on the time from the threshold TH-U1 to the threshold TH-U3 or the time from the threshold TH-U2 to the threshold TH-U3. The state of the fault sign can also be estimated by comparing the time from the threshold TH-U1 to the threshold TH-U3 and the time from the threshold TH-U2 to the threshold TH-U3.

[0048] In addition, even if multiple thresholds are not used, the time until the fault sign is obtained by acquiring the set value data of the transmission waveform adjustment in time series can also be predicted. In this case, at least one threshold (for example, threshold TH-U3) is set. For example, the time when the threshold TH-U3 is reached can be estimated based on the degree of the inclination or rising curve of the data (time series data) after the set value data of the transmission waveform adjustment is acquired in time series. In this way, by capturing the change in time using the time series data, the fault sign can be diagnosed. In addition, compared with the judgment using time series data, the judgment using multiple thresholds has the effect of reducing the amount of data.

[0049] In addition, the acquired set value data of the transmission waveform adjustment can also be used to diagnose fault signs using statistical methods or machine learning.

[0050] Next, the sequence of the fault sign diagnosis in the setting value data change diagnosis unit 109 is described. For example, the case where the communication device 1 performs the fault sign diagnosis at startup is described as an example. First, the fault sign diagnosis during loopback is performed in the communication device 1, and the communication device 1 itself is confirmed by self-diagnosis whether there is a problem. Next, the communication device 1 performs the fault sign diagnosis during normal transmission and reception. For example, in the communication device 1, the setting value data change diagnosis unit 109 obtains the setting value data of the transmission waveform adjustment of the following four modes. (1) Setting value data 2 for adjusting the transmission waveform of the emphasis circuit 102 during loopback (2) Setting value data 2 for adjusting the transmission waveform of the equalizer circuit 105 during loopback (3) Setting value data 1 for adjusting the transmission waveform of the emphasis circuit 102 during normal transmission and reception (4) Setting value data 1 for adjusting the transmission waveform of the equalizer circuit 105 during normal transmission and reception

[0051] Then, the setting value data change diagnosis unit 109 performs a fault sign diagnosis on the setting value data adjusted for each transmission waveform in (1) to (4) above based on a predetermined determination condition. When the setting value data change diagnosis unit 109 determines that there is a fault sign, it outputs a fault sign signal from the signal line 16 to a device outside the communication device 1.

[0052] Next, use Figure 3 Different situations in which the predicted failure-evidence diagnosis results in the communication device alone according to the present embodiment differ will be described. Figure 3 FIG. 2 is a diagram showing a table in which the predicted failure sign diagnosis results in the communication device 1 alone are classified into different cases. Figure 3Table 3 showing the case classification includes items such as "No.", "Communication device 1→2 (normal)", "Communication device 1 (loopback)", "Communication device 2→1 (normal)", and "Failure sign location".

[0053] "No." is an identifier (for example, a number) for uniquely identifying a row (record) in a table. "Communication device 1 → 2 (normal)" indicates a normal communication state in which a data signal is transmitted from communication device 1 to communication device 2. In the figure, "○" indicates normal, and "×" indicates a failure sign state. “Communication device 1 (loopback)” indicates a communication state when loopback is performed in the communication device 1 . "Communication device 2 → 1 (normal)" indicates a normal communication state in which a data signal is transmitted from the communication device 2 to the communication device 1. In the figure, "○" indicates normal, and "×" indicates a failure sign state. The “predicted failure sign location” indicates the predicted failure sign location determined based on the communication states indicated by “communication device 1 → 2 (normal)”, “communication device 1 (loopback)”, and “communication device 2 → 1 (normal)”.

[0054] In addition to the usual diagnosis during transmission and reception, the diagnosis during loopback is also added, thereby being able to determine whether the communication device 1 itself is normal or in a state of failure sign. However, since the failure sign state of the communication device 2 is unknown, it is sometimes impossible to determine the failure sign location ( Figure 3 No.3, No.4, No.7).

[0055] For example, in the data of No. 3, "communication device 1→2 (normal)" is in a state of forewarning of a fault, "communication device 1 (loopback)" is normal, and "communication device 2→1 (normal)" is in a state of forewarning of a fault. In addition, in the data of No. 4, "communication device 1→2 (normal)" is in a state of forewarning of a fault, "communication device 1 (loopback)" is normal, and "communication device 2→1 (normal)" is normal. And, in the data of No. 7, "communication device 1→2 (normal)" is normal, "communication device 1 (loopback)" is normal, and "communication device 2→1 (normal)" is in a state of forewarning of a fault. In the case of any of the data of No. 3, No. 4, and No. 7, "communication device 1" or "transmission line 10" may be a forewarning of a fault location.

[0056] In addition, in this embodiment, by adding the diagnosis during loopback to the diagnosis during normal transmission and reception, it is sometimes possible to infer which of the transmission circuit or reception circuit of the communication device 1 has a sign of failure. For example, in the data of No. 2, "communication device 1→2 (normal)" is in a state of sign of failure, "communication device 1 (loopback)" is in a state of sign of failure, and "communication device 2→1 (normal)" is normal. In the case of this combination, since "communication device 1 (loopback)" is in a state of sign of failure and "communication device 2→1 (normal)" is normal, it can be determined that there is a sign of failure in the transmission circuit of the communication device 1.

[0057] Similarly, in the data of No. 5, "communication device 1→2 (normal)" is normal, "communication device 1 (loopback)" is in a fault sign state, and "communication device 2→1 (normal)" is in a fault sign state. In the case of this combination, since "communication device 1 (loopback)" is in a fault sign state and "communication device 1→2 (normal)" is normal, it can be determined that there is a fault sign in the receiving circuit of communication device 1. In this way, by being able to infer whether the fault sign occurs in the transmission circuit or the receiving circuit in the communication device, it is helpful to analyze the failure of the circuit board mounted on the communication device or the communication device.

[0058] In addition, the diagnosis of the communication state, that is, the diagnosis of the fault sign, can be performed based on "communication device 1 (loopback)". When "communication device 1 (loopback)" is in the fault sign state, regardless of the diagnosis results of "communication device 1→2 (normal)" and "communication device 2→1 (normal)", it can be determined that there is a fault sign (No.1, No.2, No.5, No.6) in communication device 1. As a result, the diagnosis of "communication device 1→2 (normal)" and "communication device 2→1 (normal)" can be omitted.

[0059] As described above, the communication device of this embodiment (for example, communication device 1) is a communication device for transmitting data signals, which includes: a sending circuit (sending processing circuit 101 to sending output circuit 103), which sends data signals; a receiving circuit (receiving input circuit 104 to receiving processing circuit 107), which receives data signals; and a set value data change diagnostic unit (set value data change diagnostic unit 109). The set value data change diagnosis unit is configured to use the first set value data for adjusting the transmission waveform when a data signal is transmitted and received with an external device (for example, communication device 2) via a transmission line (communication device 1→2 (normal), communication device 2→1 (normal)) and the second set value data for adjusting the transmission waveform when a data signal is looped back between a transmitting circuit and a receiving circuit (communication device 1 (loopback)), and to determine the change of the first set value data when a data signal is transmitted and received with an external device via a transmission line and the change of the second set value data when a data signal is looped back between a transmitting circuit and a receiving circuit according to a prescribed determination condition, and to diagnose a sign of failure of the communication device and the transmission line according to the determination result.

[0060] According to the communication device (e.g., communication device 1) of the present embodiment described above, by adding the diagnosis during loopback to the diagnosis during transmission and reception with an external device (e.g., communication device 2) via a transmission line, it is possible to diagnose a fault sign based on the set value data adjusted by the transmission waveform under different conditions. Thus, the communication device itself can be self-diagnosed, and the accuracy of fault sign diagnosis is improved. In the present embodiment, it is possible to grasp whether the communication device (e.g., communication device 1) of the diagnosis object is in a fault sign state.

[0061] In this way, since the communication device (component) showing a sign of failure can be identified, for example, only the component that needs to be replaced can be replaced or maintenance can be performed, resulting in a reduction in component costs and maintenance man-hours.

[0062] Next, use Figure 4 A description will be given of a case where the predicted failure-evidence diagnosis results in two communication devices differ according to the present embodiment. Figure 4 1 is a diagram showing a table in which the predicted failure-evidence diagnosis results in the two communication devices 1 and 2 are classified into different cases. Figure 4 The example is an example of determining the predicted fault location using the predicted fault diagnosis results of the communication device 1 and the communication device 2. Figure 3 The situation shown in Table 3 is distinguished. Figure 4 The table 4 for case classification shown in the figure has an additional item of "communication device 2 (loopback)". That is, the table 4 for case classification has items of "No.", "communication device 1→2 (normal)", "communication device 1 (loopback)", "communication device 2→1 (normal)", "communication device 2 (loopback)" and "failure sign location".

[0063] In this embodiment, it is assumed that the predicted failure signs of the internal circuits of the communication device 1 and the communication device 2 can be detected by the predicted failure sign diagnosis during loopback. Figure 4As can be seen from Table 4 showing the different situations, by adding the diagnosis during loopback to the diagnosis during normal transmission and reception, one or more predicted failure locations can be identified from the communication device 1 , the communication device 2 , and the transmission line 10 .

[0064] For example, Figure 3 The fault sign diagnosis result in "No.3" of Table 3 shown corresponds to Figure 4 The fault sign diagnosis results of "No. 5" and "No. 6" in Table 4 are shown. In "No. 5" in Table 4, when "communication device 1→2 (normal)" is in the fault sign state, "communication device 1 (loopback)" is normal, and "communication device 2→1 (normal)" is in the fault sign state, and "communication device 2 (loopback)" is in the fault sign state, the communication device 2 can be determined as the fault sign part. Similarly, in "No. 6" in Table 4, when "communication device 1→2 (normal)" is in the fault sign state, "communication device 1 (loopback)" is normal, and "communication device 2→1 (normal)" is in the fault sign state, and "communication device 2 (loopback)" is normal, the transmission line 10 can be determined as the fault sign part.

[0065] in addition, Figure 3 The fault sign diagnosis result in "No. 4" of Table 3 shown corresponds to Figure 4 The fault sign diagnosis results of "No.7" and "No.8" in Table 4 are shown. In "No.7" in Table 4, when "communication device 1→2 (normal)" is in the fault sign state, "communication device 1 (loopback)" is normal, and "communication device 2→1 (normal)" is normal, and "communication device 2 (loopback)" is in the fault sign state, the communication device 2 can be determined as the fault sign part. Similarly, in "No.8" in Table 4, when "communication device 1→2 (normal)" is in the fault sign state, "communication device 1 (loopback)" is normal, and "communication device 2→1 (normal)" is normal, and "communication device 2 (loopback)" is normal, the transmission line 10 can be determined as the fault sign part.

[0066] In addition, for example, Figure 3 The fault sign diagnosis result in "No.7" of Table 3 shown corresponds to Figure 4The fault sign diagnosis results of "No. 13" and "No. 14" in Table 4. In "No. 13" in Table 4, when "communication device 1→2 (normal)" is normal, "communication device 1 (loopback)" is normal, and "communication device 2→1 (normal)" is in a fault sign state, and "communication device 2 (loopback)" is in a fault sign state, the communication device 2 can be determined as the fault sign part. Similarly, in "No. 14" in Table 4, when "communication device 1→2 (normal)" is normal, "communication device 1 (loopback)" is normal, and "communication device 2→1 (normal)" is in a fault sign state, and "communication device 2 (loopback)" is normal, the transmission line 10 can be determined as the fault sign part.

[0067] In addition, if Figure 4 As shown, even in the case of performing the diagnosis of "communication device 2 (loopback)" in addition to "communication device 1 → 2 (normal)", "communication device 1 (loopback)", and "communication device 2 → 1 (normal)", according to Figure 3 For the reasons described above, the diagnosis of the communication state, that is, the diagnosis of the failure sign can also be performed based on the "communication device 1 (loopback)" and the "communication device 2 (loopback)".

[0068] As described above, the communication system of the present embodiment is a communication system including a first communication device (e.g., communication device 1) and a second communication device (e.g., communication device 2) for transmitting a data signal. The first communication device and the second communication device are respectively provided with: a transmission circuit (transmission processing circuit 101 to transmission output circuit 103, transmission processing circuit 201 to transmission output circuit 203) for transmitting a data signal; a receiving circuit (reception input circuit 104 to reception processing circuit 107, reception input circuit 204 to reception processing circuit 207) for receiving a data signal; and a setting value data change diagnosis unit (setting value data change diagnosis unit 109, 209). The setting value data change diagnosis unit is configured to use the first setting value data for adjusting the transmission waveform when a data signal is transmitted and received between the first communication device and the second communication device via a transmission line (communication device 1→2 (normal), communication device 2→1 (normal)), the second setting value data for adjusting the transmission waveform when a loopback occurs between a transmission circuit and a reception circuit in the first communication device (communication device 1 (loopback)), and the third setting value data for adjusting the transmission waveform when a loopback occurs between a transmission circuit and a reception circuit in the second communication device (communication device 2 (loopback)), and determine the change of the first setting value data when a data signal is transmitted and received between the first communication device and the second communication device via a transmission line, the change of the second setting value data when a loopback occurs between a transmission circuit and a reception circuit in the first communication device, and the change of the third setting value data when a loopback occurs between a transmission circuit and a reception circuit in the second communication device according to a predetermined determination condition, and diagnose the failure signs of the first communication device, the second communication device, and the transmission line according to the determination results, and determine the part having the failure sign.

[0069] According to the communication system (for example, including communication devices 1 and 2) of the present embodiment described above, in the diagnosis when sending and receiving between two communication devices (for example, communication devices 1 and 2) via the transmission line, in addition to the diagnosis when looping back in each communication device, by performing fault sign diagnosis, it is possible to determine which communication device or transmission line is the fault sign location.

[0070] In this way, since the communication device (component) showing a sign of failure can be identified, for example, only the component that needs to be replaced can be replaced or maintenance can be performed, resulting in a reduction in component costs and maintenance man-hours.

[0071] [Variation (1) of the first embodiment] Next, refer to Figure 5 A modified example (1) of the communication device according to the present embodiment will be described. Figure 5 This is a block diagram showing an example of the internal configuration when the communication device of the present embodiment is provided with a temperature detection unit (temperature detection circuit). This example is an example of a case where the influence of the temperature of the communication device is taken into consideration in the failure sign diagnosis.

[0072] exist Figure 1The communication device 1 and the communication device 2 shown in the figure are respectively provided with a temperature detection unit 111 and a temperature detection unit 211 for detecting the temperature inside the communication device. The setting value data change diagnosis unit 109, 209 changes the judgment threshold of the fault sign diagnosis according to the temperature inside the communication device 1, 2 detected by the temperature detection unit 111, 211. In this way, it is possible to prevent the situation where the setting value data for adjusting the transmission waveform of the data signal is erroneously judged as a fault sign state when it changes due to the influence of temperature. As a method for changing the threshold value corresponding to the temperature, for example, a method can be considered in which the temperature dependence of the setting value data is measured during the product factory inspection and the threshold value information corresponding to the temperature inside the communication device is pre-stored.

[0073] [Modification (2) of the first embodiment] Next, refer to Figure 6 A modification example (2) of the communication device according to the present embodiment will be described. Figure 6 This is a block diagram showing an example of the internal configuration when a power supply voltage detection unit (power supply voltage detection circuit) is provided in the communication device of the present embodiment. This example is an example of a case where the influence of the power supply voltage of the communication device is taken into consideration in the failure sign diagnosis.

[0074] exist Figure 1 The communication device 1 and the communication device 2 shown in the figure are respectively provided with a power supply voltage detection unit 112 and a power supply voltage detection unit 212. The setting value data change diagnosis unit 109, 209 changes the judgment threshold of the fault sign diagnosis according to the power supply voltage provided to the communication devices 1, 2 detected by the power supply voltage detection unit 112, 212. In this way, it is possible to prevent the setting value data for adjusting the transmission waveform of the data signal from being erroneously judged as a fault sign state when it changes due to the influence of the power supply voltage. As a method of changing the threshold value corresponding to the power supply voltage, for example, a method of measuring the power supply voltage dependency of the setting value data during the product factory inspection and pre-storing the threshold value information corresponding to the power supply voltage is considered.

[0075] [Communication system including host device] Next, refer to Figure 7 In the communication system of the present embodiment, a configuration is described in which information on the predicted-failure-evidence diagnosis results is collected in the host device and the predicted-failure-evidence location is identified by the host device.

[0076] Figure 7 This is a diagram showing an example of a configuration in which information on the failure sign diagnosis results is collected in a host device in a communication system, and the failure sign location is determined by the host device. Figure 7, there is shown a configuration example in which information on the failure sign diagnosis results of the setting value data change diagnosis units 109 and 209 of the communication device 1 and the communication device 2 are collected in the host device 300, and the communication device and the transmission line having the failure sign part are determined by the host device 300.

[0077] In this example, the electronic control device 100 having the communication device 1 further has the communication device 3, and the electronic control device 200 having the communication device 2 further has the communication device 5. In the electronic control device 100, the communication device 1 and the communication device 3 are connected via the signal line 16. Similarly, in the electronic control device 200, the communication device 2 and the communication device 5 are connected via the signal line 26. The communication device 3 may have the same configuration as the communication device 1, or may have a configuration without the setting value data change diagnosis unit 109 of the communication device 1. Similarly, the communication device 5 may have the same configuration as the communication device 2, or may have a configuration without the setting value data change diagnosis unit 209 of the communication device 2.

[0078] The host device 300 includes a communication device 4, a communication device 6, and a microcomputer 310 for determining a predicted fault location based on a predicted fault diagnosis result. The communication device 3 of the electronic control device 100 and the communication device 4 of the host device 300 are connected via a transmission line 30. In addition, the communication device 5 of the electronic control device 200 and the communication device 6 of the host device 300 are connected via a transmission line 50. The communication device 4 may have the same structure as the communication device 1, or may have a structure without the setting value data change diagnosis unit 109 of the communication device 1. Similarly, the communication device 6 may have the same structure as the communication device 2, or may have a structure without the setting value data change diagnosis unit 209 of the communication device 2.

[0079] The failure sign diagnosis result of the communication device 1 is sent to the microcomputer 310 from the signal line 16 via the communication device 3, the transmission line 30, and the communication device 4. That is, the failure sign diagnosis result of the communication device 1 is sent from the setting value data change diagnosis unit 109 to the transmission processing circuit 101 of the communication device 3 via the signal line 16. Then, in normal data communication, the failure sign diagnosis result is sent from the input-output unit 108 of the communication device 3 to the input-output unit 108 of the communication device 4 via the transmission line 30. Furthermore, the failure sign diagnosis result is sent from the reception processing circuit 107 of the communication device 4 to the microcomputer 310.

[0080] Similarly, the failure sign diagnosis result of the communication device 2 is sent from the signal line 26 to the microcomputer 310 via the communication device 5, the transmission line 50, and the communication device 6. Since the specific communication path for sending the failure sign diagnosis result of the communication device 2 from the signal line 26 to the microcomputer 310 via the communication device 5, the transmission line 50, and the communication device 6 is the same as the communication path for the failure sign diagnosis result of the communication device 1, the detailed description is omitted.

[0081] Then, in the microcomputer 310 , based on the predicted failure-evidence diagnosis result of the communication device 1 and the predicted failure-evidence diagnosis result of the communication device 2 , the predicted failure-evidence locations of the communication device 1 , the communication device 2 , and the transmission line 10 are specified.

[0082] In addition, instead of the failure sign diagnosis result, the setting value data of the transmission waveform adjustment of the emphasis circuit 102 and the equalizer circuit 105 of the communication device 1 and the setting value data of the transmission waveform adjustment of the emphasis circuit 202 and the equalizer circuit 205 of the communication device 2 may be sent to the host device 300. The microcomputer 310 of the host device 300 can also collect the setting value data of each circuit sent by the communication device 1 and the setting value data of each circuit sent by the communication device 2 to perform the failure sign diagnosis and determine the failure sign location.

[0083] For example, consider a case where a vehicle is equipped with a plurality of communication devices 1 to 6. If there are ECUs (Electronic Control Units) having communication devices 1 and 3, and ECUs having communication devices 2 and 5, then host device 300 is equivalent to an integrated ECU that performs integrated control of these ECUs.

[0084] As described above, the communication system of this embodiment is a communication system including a first communication device (eg, communication device 1 ) that transmits data signals, a second communication device (eg, communication device 2 ), and an information processing device (host device 300 ). The first communication device and the second communication device respectively include: a sending circuit (sending processing circuit 101 to sending output circuit 103, sending processing circuit 201 to sending output circuit 203), which sends a data signal; a receiving circuit (receiving input circuit 104 to receiving processing circuit 107, receiving input circuit 204 to receiving processing circuit 207), which receives a data signal; and a setting value data change diagnosis unit (setting value data change diagnosis unit 109, 209). The setting value data variation diagnosis unit is configured to use first setting value data for adjusting a transmission waveform when a data signal is transmitted and received between a first communication device and a second communication device via a transmission line (communication device 1→2 (normal), communication device 2→1 (normal)), second setting value data for adjusting a transmission waveform when a loopback is performed between a transmission circuit and a reception circuit in the first communication device (communication device 1 (loopback)), and third setting value data for adjusting a transmission waveform when a loopback is performed between a transmission circuit and a reception circuit in the second communication device (communication device 2 (loopback)), and determine, based on a predetermined determination condition, a variation of the first setting value data when a data signal is transmitted and received between the first communication device and the second communication device via a transmission line, a variation of the second setting value data when a loopback is performed between a transmission circuit and a reception circuit in the first communication device, and a variation of the third setting value data when a loopback is performed between a transmission circuit and a reception circuit in the second communication device, and diagnose a sign of failure of the first communication device, the second communication device, and the transmission line based on the determination result. The information processing device is configured to acquire the predicted failure sign diagnosis result of the setting value data change diagnosis unit from the first communication device and the second communication device, and identify a location having a predicted failure sign.

[0085] According to the communication system of the present embodiment described above (for example, including communication devices 1, 2, and host device 300), the fault sign diagnosis results of multiple communication devices can be collected in an external information processing device, and the fault sign location can be determined by the information processing device. Therefore, the fault sign location can be determined in the information processing device with higher data processing capacity than the communication device.

[0086] <Second Embodiment> The second embodiment is a communication system according to the first embodiment (see Figure 7 ) An example of identifying the fault sign location by the communication device without using a host device. Figure 8 A second embodiment will be described.

[0087] Figure 8 1 is a diagram showing an example of a structure in which a communication device determines a failure sign location without using a host device in a communication system of the present embodiment. Figure 1) is added with a signal line 17 connecting the transmission processing circuit 101 and the setting value data change diagnosis unit 109, and a signal line 18 connecting the reception processing circuit 107 and the setting value data change diagnosis unit 109. Similarly, in the communication device 2, a signal line 27 connecting the transmission processing circuit 201 and the setting value data change diagnosis unit 209, and a signal line 28 connecting the reception processing circuit 207 and the setting value data change diagnosis unit 209 are added. In order to distinguish from the above-mentioned communication device 1 and communication device 2, in this embodiment, they are described as communication device 1A and communication device 2A.

[0088] In the communication device 1A, the predicted fault sign diagnosis result of the setting value data change diagnosis unit 109 is sent to the transmission processing circuit 101 via the signal line 17, and is sent to the communication device 2A through normal data communication. The predicted fault sign diagnosis result of the communication device 1A that has reached the communication device 2A is sent from the reception processing circuit 207 to the setting value data change diagnosis unit 209 via the signal line 28. In the setting value data change diagnosis unit 209, since the predicted fault sign diagnosis results of the communication device 1A and the communication device 2A are collected, the predicted fault sign locations of the communication device 1A, the communication device 2A, and the transmission line 10 can be identified.

[0089] On the contrary, in the communication device 2A, the predicted fault sign diagnosis result of the setting value data change diagnosis unit 209 is sent to the transmission processing circuit 201 via the signal line 27, and is sent to the communication device 1A through the normal data communication. The predicted fault sign diagnosis result of the communication device 2A that has reached the communication device 1A is sent from the reception processing circuit 107 to the setting value data change diagnosis unit 109 via the signal line 18. In the setting value data change diagnosis unit 109, since the predicted fault sign diagnosis results of the communication device 1A and the communication device 2A are collected, the predicted fault sign parts of the communication device 1A, the communication device 2A, and the transmission line 10 can be determined. The result obtained by the communication device 1A determining the predicted fault sign part is output to the device outside the communication device 1A via the signal line 16. Similarly, the result obtained by the communication device 2A determining the predicted fault sign part is output to the device outside the communication device 2A via the signal line 26.

[0090] <Third Embodiment> The third embodiment is an example in which the determination threshold used in the predicted failure sign diagnosis of the communication device is changed in accordance with an instruction from an external device.

[0091] Fig. 9 This is a diagram showing an example of a configuration in which a determination threshold used in the predicted failure sign diagnosis of a communication device is changed in accordance with an instruction from an external device in the communication system according to the present embodiment. Fig.10This is a diagram showing an example of a configuration in which an instruction from an external device is transmitted and received between two communication devices by wireless communication in the communication system according to the present embodiment.

[0092] like Fig. 9 As shown, the communication device 1B of this embodiment is a device which is a device of the above-mentioned communication device 1A (see Figure 8 ) is provided with a signal line T1 connecting the transmission processing circuit 101 and the external device, and a signal line R1 connecting the reception processing circuit 107 and the external device. Similarly, the communication device 2B is provided with a signal line T2 connecting the transmission processing circuit 201 and the external device, and a signal line R2 connecting the reception processing circuit 207 and the external device on the communication device 2A.

[0093] In addition, in the communication device 1B, the signal line 16 for outputting the predicted fault diagnosis result from the setting value data change diagnosis unit 109 existing in the communication device 1A is deleted, and the predicted fault diagnosis result is output from the signal line R1 via the signal line 18 and the reception processing circuit 107. Similarly, in the communication device 2B, the signal line 26 for outputting the predicted fault diagnosis result from the setting value data change diagnosis unit 209 existing in the communication device 2A is deleted, and the predicted fault diagnosis result is output from the signal line R2 via the signal line 28 and the reception processing circuit 207.

[0094] use Fig.10 An example of a method of changing the determination threshold of the failure sign diagnosis of the communication device 1B and the communication device 2B according to an instruction from an external device will be described. Fig.10 In the embodiment, the electronic control device 100B can transmit and receive data signals with the electronic control device 200B via the transmission line 10. In addition, the electronic control device 100B can transmit and receive data signals with the server 400 (an example of an external device) by wireless communication. The electronic control device 200 has a wired communication function, but can also be configured in the same manner as the electronic control device 100 having a wireless communication function.

[0095] For example, in the case of utilizing wireless communication, the instruction data from the external device (e.g., the server 400) received by the antenna 130 provided in the electronic control device 100B is transmitted to the microcomputer 110 that controls the electronic control device 100B via the wireless communication module 120. The instruction data from the external device includes information for changing the determination threshold of the fault sign diagnosis. In addition, the instruction data from the external device is transmitted from the microcomputer 110 to the transmission processing circuit 101 of the communication device 1B via the signal line T1. In the communication device 1B, the instruction data is transmitted from the transmission processing circuit 101 to the setting value data change diagnosis unit 109 via the signal line 17. Therefore, the setting value data change diagnosis unit 109 can change the determination threshold of the fault sign diagnosis according to the instruction from the external device.

[0096] On the other hand, in the communication device 2B mounted on the electronic control device 200B, the instruction data from the external device is transmitted to the setting value data change diagnosis unit 209 via the communication device 1B, the transmission line 10, the receiving circuit from the input / output unit 208 to the receiving processing circuit 207, and the signal line 28. Therefore, the setting value data change diagnosis unit 209 can change the determination threshold value of the failure sign diagnosis according to the instruction from the external device.

[0097] In this way, the setting value data change diagnosis unit 109, 209 can obtain instructions from an external device via a communication network based on wireless communication, and change the threshold value of the fault sign diagnosis according to the instructions from the external device. For example, in the case of an on-board communication device, the setting value data change diagnosis unit 109, 209 in the communication device obtains information on the fault occurrence status in the same vehicle model as an instruction from the external device, and changes the judgment condition according to the information on the fault occurrence status, which can improve the accuracy of the fault sign diagnosis. For example, the so-called change of judgment condition refers to changing Figure 2 As an example, when it is desired to detect a sign of failure of a certain component at an early stage based on the failure occurrence status of the same vehicle model, a measure of reducing the value of the threshold TH-U3 to approach the threshold TH-U2 is considered.

[0098] exist Fig.10In the example, on the contrary, wireless communication can also be used to send the fault sign diagnosis results of the communication device 1B and the communication device 2B and the setting value data of the transmission waveform adjustment to the external device of the communication device 1 and the communication device 2, such as the server 400. In the server 400, the fault sign diagnosis results and the setting value data of the transmission waveform adjustment sent can be used to implement the fault sign diagnosis. In addition, the server 400 can also return the obtained fault sign diagnosis results to the electronic control device 100B, 200B (communication device 1B, 2B) and the like through wireless communication. For example, if the vehicle-mounted situation is considered, the wireless communication composed of the wireless communication module 120 and the antenna 130 is equivalent to OTA (Over the Air).

[0099] In addition, the external device may be a maintenance terminal used by maintenance personnel during maintenance. The maintenance terminal is connected to a connector connected to the vehicle Ethernet, so that the maintenance terminal and the electronic control device 100B, 200B are connected so as to be communicable. The maintenance personnel sends an instruction to operate the maintenance terminal to change the threshold value of the fault sign diagnosis to the communication device 1B, 2B of the electronic control device 100B, 200B.

[0100] [Computer hardware configuration] Below, refer to Fig.11 The hardware configuration of the communication device, the microcomputer, and the computer included in the server in each of the above-mentioned embodiments will be described.

[0101] Fig.11 This is a block diagram showing a hardware configuration example of a communication device, a microcomputer, and a computer included in a server according to each embodiment of the present invention. Fig.11 The calculator 500 shown is hardware used as a so-called computer.

[0102] The calculator 500 includes a CPU (Central Processing Unit) 501 , a ROM (Read Only Memory) 502 , a RAM (Random Access Memory) 503 , a nonvolatile memory 506 , and a network interface 507 , each of which is connected to a bus.

[0103] The CPU 501 is an example of a processor as a computing device, and the ROM 502 and the RAM 503 are examples of memories.

[0104] The nonvolatile memory 506 is a nonvolatile storage element having a larger capacity than the memory. The program for realizing the functions of the communication device of each embodiment of the present invention is stored in the nonvolatile memory 506. The nonvolatile memory 506 is an example of a non-transient recording medium readable by a computer. In addition, the program may also be stored in the ROM 502. At least, in the case where the functions of the setting value data change diagnosis unit 109 and 209 are realized by software, the CPU 501 executes the program stored in the ROM 502 or the nonvolatile memory 506 to realize the functions of the setting value data change diagnosis unit.

[0105] In addition, the determination threshold value ( Figure 2 ) and the classification of the fault warning diagnosis results ( Figure 3 , Figure 4 ), and the data obtained by acquiring the set value data of the transmission waveform adjustment in time series ( Figure 2 )wait.

[0106] In addition, in using Figure 7 The microcomputer 310 of the host device 300 or Fig.10 When the server 400 has a function of diagnosing fault signs or determining the location of fault signs, a program that implements the same function as the setting value data change diagnosis unit 109, 209 is recorded in the ROM 502 or non-volatile memory 506 possessed by the microcomputer 310 and the server 400.

[0107] The network interface 507 is composed of a communication device, etc., which controls the communication with other devices (such as ECU) through a communication line or a network such as an in-vehicle Ethernet. For example, the input and output units 108 and 208 of the communication device are implemented by the network interface 507. Fig.10 The wireless communication module 120 in the electronic control device 100B is an example of the network interface 507 .

[0108] Furthermore, the present invention is not limited to the above-mentioned embodiments. Of course, various other application examples and modified examples may be adopted without departing from the scope of the main purpose of the present invention described in the claims. For example, the above-mentioned embodiments are detailed and specific descriptions of the composition in order to easily explain the present invention, and are not necessarily limited to having all the constituent elements described. In addition, constituent elements of other embodiments may be used to replace a part of the composition of certain embodiments. Constituent elements of other embodiments may also be added to the composition of certain embodiments. In addition, for a part of the composition of each embodiment, other constituent elements may also be added, replaced, or deleted.

[0109] In addition, the above-mentioned various structures, functions, processing units, etc. can also be implemented in part or in whole by hardware, for example, by designing with integrated circuits. As hardware, a broad processor device such as FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit) can also be used. In addition, the above-mentioned various structures, functions, processing units, etc. can also be implemented by software by interpreting and executing a program that realizes each function through a processor possessed by a computer.

[0110] In the above-mentioned embodiments, control lines and information lines are shown as lines that are considered necessary for explanation, and not all control lines and information lines are shown in the product. In reality, it can be considered that almost all components are connected to each other. Explanation of symbols

[0111] 1 to 6…communication device, 1A, 2A…communication device, 1B, 2B…communication device, 10, 30, 50…transmission line, 101, 201…transmission processing circuit, 102, 202…emphasis circuit, 103, 203…transmission output circuit, 104, 204…reception input circuit, 105, 205…equalizer circuit, 106, 206…error detection unit, 107, 207…reception processing circuit, 108, 208…input and output unit, 109, 209…set value data change adjustment unit, 100, 200…electronic control unit, 100B, 200B…electronic control unit, 111, 211…temperature detection unit, 112, 212…power supply voltage detection unit, 300…host device, 110, 310…microcomputer

Claims

1. A communication device for transmitting a data signal, characterized in that: have: a transmitting circuit that transmits a data signal; a receiving circuit that receives a data signal; and A set value data change diagnosis unit uses first set value data for adjusting a transmission waveform when a data signal is transmitted and received via a transmission line with an external device, and second set value data for adjusting a transmission waveform when a data signal is looped back between the transmitting circuit and the receiving circuit, and determines changes in the first set value data when the data signal is transmitted and received via the transmission line with the external device, and changes in the second set value data when the data signal is looped back between the transmitting circuit and the receiving circuit, respectively, according to prescribed determination conditions, and diagnoses signs of failure of the communication device and the transmission line based on the determination results.

2. The communication device according to claim 1, characterized in that The first set value data and the second set value data for adjusting the transmission waveform are set values ​​of tap coefficients of a transfer function of an emphasis circuit or set values ​​of tap coefficients of a transfer function of an equalizer circuit.

3. The communication device according to claim 1, characterized in that The timing when the setting value data change diagnosis unit performs the diagnosis of the failure sign is when the communication device is started or stopped.

4. The communication device according to claim 1, characterized in that: A temperature detection circuit is provided to detect the temperature in the communication device. The set value data change diagnostic unit changes the determination condition according to the temperature detected by the temperature detection circuit.

5. The communication device according to claim 1, characterized in that: A power supply voltage detection circuit is provided for detecting a power supply voltage supplied to the communication device. The setting value data change diagnostic unit changes the determination condition according to the power supply voltage detected by the power supply voltage detection circuit.

6. The communication device according to claim 1, characterized in that: The setting value data change diagnosis unit changes the determination condition according to an instruction from an external device of the communication device.

7. The communication device according to claim 1, characterized in that: The setting value data change diagnosis unit diagnoses the predicted failure sign based on a plurality of threshold values ​​or a temporal change in time series data of the first setting value data and the second setting value data.

8. A communication system comprising a first communication device and a second communication device for transmitting a data signal, wherein the communication system is characterized in that: The first communication device and the second communication device respectively include: a transmitting circuit that transmits a data signal; a receiving circuit that receives a data signal; and A set value data change diagnosis unit uses first set value data for adjusting a transmission waveform when a data signal is transmitted and received via a transmission line between the first communication device and the second communication device, second set value data for adjusting a transmission waveform when a loopback occurs between the transmitting circuit and the receiving circuit in the first communication device, and third set value data for adjusting a transmission waveform when a loopback occurs between the transmitting circuit and the receiving circuit in the second communication device, and determines, based on a predetermined determination condition, a change in the first set value data when a data signal is transmitted and received via a transmission line between the first communication device and the second communication device, a change in the second set value data when a loopback occurs between the transmitting circuit and the receiving circuit in the first communication device, and a change in the third set value data when a loopback occurs between the transmitting circuit and the receiving circuit in the second communication device, and diagnoses a failure sign of the first communication device, the second communication device, and the transmission line based on the determination result, and determines a portion having the failure sign.

9. A communication system comprising a first communication device, a second communication device and an information processing device for transmitting a data signal, wherein the communication system is characterized in that: The first communication device and the second communication device respectively include: a transmitting circuit that transmits a data signal; a receiving circuit that receives a data signal; and a set value data change diagnosis unit, which uses first set value data for adjusting a transmission waveform when a data signal is transmitted and received via a transmission line between the first communication device and the second communication device, second set value data for adjusting a transmission waveform when a loopback occurs between the transmitting circuit and the receiving circuit in the first communication device, and third set value data for adjusting a transmission waveform when a loopback occurs between the transmitting circuit and the receiving circuit in the second communication device, and based on a predetermined determination condition, determines a change in the first set value data when a data signal is transmitted and received via a transmission line between the first communication device and the second communication device, a change in the second set value data when a loopback occurs between the transmitting circuit and the receiving circuit in the first communication device, and a change in the third set value data when a loopback occurs between the transmitting circuit and the receiving circuit in the second communication device, and diagnoses a sign of failure of the first communication device, the second communication device, and the transmission line based on the determination result, The information processing device acquires the predicted failure sign diagnosis result of the setting value data change diagnosis unit from the first communication device and the second communication device, and specifies a location having the predicted failure sign.

10. A method for diagnosing a fault sign, which is a communication device for transmitting and receiving data signals through a transmitting circuit and a receiving circuit, characterized in that: This includes the following processing: Processing of using first set value data for adjusting a transmission waveform when transmitting and receiving a data signal with an external device via a transmission line, and second set value data for adjusting a transmission waveform when looping back the data signal between the transmitting circuit and the receiving circuit, and determining changes in the first set value data when transmitting and receiving the data signal with the external device via the transmission line, and changes in the second set value data when looping back the data signal between the transmitting circuit and the receiving circuit, respectively, according to a predetermined determination condition; as well as A process of diagnosing a sign of failure of the communication device and the transmission line based on the determination result.

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