JPH06129949A - Failure diagnosis information communication device - Google Patents

Abstract

PURPOSE:To configure a data transmission line connecting a plurality of electronic control units (ECU) and a tester in a single serial transmission line and at the same time transmit information for diagnosing failure which is transmitted from a plurality of ECUs to the tester while avoiding collision on the transmission line. CONSTITUTION:A single serial transmission line L0 for transmitting information to and receiving information from a plurality of ECUs 1A and 2A and a tester 310 which diagnoses failure by obtaining information for diagnosing failure from the ECUs 1A and 2A is provided and at the same time a priority for transmitting the information for diagnosing failure to the tester 310 is set to the ECUs 1A and 2A and then own information for diagnosis failure is transmitted to the tester 310 via the serial transmission line L0 with a time difference according to the priority.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a failure diagnosis information communication device for transmitting information for failure diagnosis from an electronic device mounted on each vehicle to a diagnosis device through a serial transmission line.

[0002]

2. Description of the Related Art FIG. 6 shows, for example, Japanese Utility Model Laid-Open No. 63-163444.
It is a block diagram which shows the system configuration of the conventional failure diagnosis information communication device shown in the publication. In the figure, 1, 2,
... 8 is an electronic control unit (hereinafter referred to as an ECU) mounted on a vehicle, and each of the ECUs 1, 2, ... 8 is a control process for an electronic device in the vehicle and a data for failure diagnosis of the electronic device ( (Information) transmission / reception processing, CPUs 11 to 18, transmission buffers TX and reception buffers RX connected to the respective CPUs, which transmit and receive data to and from a tester as a failure diagnosis device described later, and signals for confirming communication initialization from the tester. And a receiving buffer CH for receiving the received data.

Reference numeral 31 is a tester for diagnosing failure of each of the ECUs ₁ , ₂ , ... ₈ , The communication lines m ₁ , m ₂ ,.
2, ... Transmit buffer TX and receive buffer RX for every 8
ECU-side signal lines L ₁ , L ₂ , ... L _{8 connected} to
The ECU 1, 2, ... 8 receives a diagnostic command, which is data requesting fault diagnostic information, and receives response data to the diagnostic command via the communication line C connected between the ground and each reception buffer CH. Perform the failure diagnosis of.

As the configuration of the tester 31, a reference numeral 31a is a CP for performing failure diagnosis processing, communication processing of diagnostic data, and the like.
U, each data is transmitted through the transmission buffer TX and the reception buffer RX by the multiplexer 31b through the communication lines m ₁ , m ₂ ,
To · · · m ₈ is selectively transmitted and received. Reference numerals 31c and 31d denote ROMs, EPROMs, and 31s in which processing programs are stored.
e is a display device for displaying the diagnosis result through the display interface 31f, 31g is a keyboard for setting a diagnosis mode and the like to the CPU 31a through the input / output encoder 31h, 31i is a buzzer for notifying a failure diagnosis judgment by a buzzer sound, and 31j is a constant of the CPU 31a. The operation of the constant voltage power supply 31j, which is a voltage power supply, is indicated by the pilot lamp 31k.

Next, the operation of the conventional failure diagnosis information communication device will be described with reference to the timing chart of FIG. 7 and the flowchart of FIG. First, the connectors 41a and 41b
, The communication lines on the tester 31 side m ₁ , m ₂ , ...
₈ and ECUs ₁ , ₂ , ... Communication lines L ₁ , L ₂ , ... on the 8 side
· L ₈ together with respectively connected, the communication line C tester 3
1 is connected to the ground. As a result, the ECUs 1, 2,
A low-level initialization signal is input to the CPUs 11, 12, ... 18 of ... 8 via the reception buffer CH (at the point of circle A in FIG. 7). And each CPU 11, 12,
.. 18 detects the low level of the initialization signal, initializes, and becomes a communication enabled state.

[0006] Next the tester 31 at circle B switches the multiplexer 31b, the tester 31 via the reception buffer RX connected to CPU 31a, the communication line m _1, L ₁ and connecting the transmit buffer TX to the communication line m ₁ A data transmission path is established between the ECU and the ECU 1. After establishing the data transmission path, C
The PU 31a sends a diagnostic command, which is data requesting information for failure diagnosis at the time of circle C, from the transmission buffer TX to the transmission buffer TX and the reception buffer RX of the ECU ₁ via the communication lines m ₁ and L ₁ to be received by the CPU 11.

Upon receiving the diagnostic command, the CPU 11 sends a preset response command from the transmission buffer TX via the communication line L ₁ to the CPU 31a of the tester 31 at the point of time D.
Send to. The data format of the diagnostic command and response data communicated between each of the ECUs 1, 2, ... 8 and the tester 31 is a 10-bit start-stop synchronous SCI format format as shown in FIG. 5B. With this data format, the effective data is 8 bits,
The 1st and 10th bits indicate the start bit and the stop bit, respectively.

Upon receiving the response data, the tester 31 displays the response data on the display device 31e via the display interface 31f. Next, when diagnosing the failure of the ECU 2, at the time of circle E, the multiplexer 31b connects the communication line to m.
_The ECU switches from ₁ to m ₂ and sends the diagnostic command transmitted from the CPU 31a to the communication line L ₂ at the time of circle F to send the ECU
Send to 2. When the ECU 2 receives the diagnostic command,
At the time of circle G, the response data is sent to the communication line L ₂ and is sent to the CPU 31a of the tester 31 like the previous response data.

When the failure diagnosis for each ECU is completed and the connectors 41a and 41b are disconnected, each E at the time of circle H
The initialization signal on the communication line C for the CUs 1, 2, ... 8 rises from low level to high level and the communication mode is released.

Next, the data communication processing of the CPU 31a in the tester 31 will be described with reference to the flowchart of FIG. First, an ECU to be diagnosed is designated (step S801), the multiplexer 31b is switched according to the designated ECU, and the ECU and the tester 31 are connected via a communication line (step S802). Subsequently, a diagnostic command is set from the keyboard 31g through the input / output encoder 31h, or change data or the like is input to set the diagnostic command (step S803), and the diagnostic command is applied to the diagnostic target through the already connected communication line. An EC
It is transmitted to U (step S804).

After transmitting the diagnostic command, the ECU waits for a reply of response data from the ECU (step S805). If there is no reply, the timer output of the internally set free-run timer is read, and the diagnostic command is determined based on the timer output. It is determined whether it is received within the time (step S807).
At this time, if it is determined that the response data is not received within the predetermined time, no response is displayed on the display device 31e (step S808). However, if it is determined in step S805 that the response data from the ECU to be diagnosed is received, the response data is displayed on the display device 31e (step S8).
06).

After the display, the CPU 31a displays a keyboard 31g.
It is further determined whether or not the change data of the ECU to be diagnosed is input (step S809). Then, if there is no change in the ECU to be diagnosed, step S80 is performed again.
Returning to step 3, the diagnostic command is transmitted again and the response data is received. However, if it is determined that the ECU to be diagnosed is changed, the process returns to step S801 to specify the ECU to be changed, and steps S802 to 809 are repeated.

Next, the ECU 1, which receives the diagnostic command,
The operation of the CPU built in 2, ... 8 will be described with reference to the flowchart of FIG. The CPU checks the level of the initialization signal while controlling various control target devices which are the original functions (steps S901 and 902). When it is determined that the signal level is the high level, the control process is continued without shifting to the communication process. However, if it is determined that the signal level is low, the arrival of the diagnostic command transmitted from the tester 31 is waited for (step S903), and the waiting is continued until the diagnostic command arrives. When the diagnostic command is received, diagnostic data corresponding to the command is transmitted to the tester 31 as response data (step S904). After transmitting the response data, the process returns to step S901 and the control process is performed until the diagnostic command is received.

[0014]

Since the conventional fault diagnosis information communication device has the system configuration as described above, communication lines for the number of ECUs are required, and therefore, the ECU is required.
As the number of communication lines increases, the number of pins of the connector for connecting the communication lines also increases with the increase in the number of communication lines, and there is a problem that maintenance of the device is troublesome.

Further, the communication system for transmitting and receiving data between the tester and each ECU is point-to-point communication in which the multiplexer on the CPU side selects the communication line connected to the ECU which is the object of failure diagnosis and transmits and receives data. However, there is a problem that it is necessary to transmit a diagnostic command for each ECU when performing a failure diagnosis for a plurality of ECUs, and it takes a long time to complete the failure diagnosis for all the ECUs as a whole. .

The present invention has been made to solve the above problems, and a data transmission line connecting a plurality of electronic devices and a diagnostic device is constituted by a single serial transmission line, and a plurality of electronic devices are connected. An object of the present invention is to obtain a failure diagnosis information communication device capable of transmitting failure diagnosis information transmitted from a device to a diagnosis device while avoiding collision on the transmission path.

[0017]

A failure diagnosis information communication device according to the present invention is a unit for transmitting and receiving information between a plurality of electronic devices and a diagnostic device that obtains failure diagnosis information from these electronic devices and performs a failure diagnosis. With one serial transmission line,
For each of the electronic devices, a priority order for transmitting the failure diagnosis information to the diagnosis apparatus is set, and the failure diagnosis information of its own is transmitted to the diagnosis apparatus through the serial transmission path with a time difference according to the priority order. It is to be transmitted.

[0018]

In the failure diagnosis information communication device according to the present invention, after transmitting the information requesting the failure diagnosis information to a plurality of electronic devices at once through the serial transmission line, each electronic device sends the information to the diagnosis device through the serial transmission line. By transmitting the failure diagnosis information at a time lag, it is possible to avoid collision of the transmission information on the transmission path.

[0019]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the system configuration of a failure diagnosis information communication device according to this embodiment. In the figure, the same reference numerals as those in FIG. 6 indicate the same or corresponding portions. In the figure, 31
0 is a tester as a diagnostic device in the present embodiment,
The CPU 31 is different from the conventional tester 31 in configuration.
A is directly connected to the communication line m ₀ via the transmission buffer TX and the reception buffer RX. Communication line m ₀ is connector 41
Communication line L that forms a serial transmission line via a and 41b
Connected to ₀ . The communication line L ₀ is branched and connected to the transmission buffer TX and the reception buffer RX of each ECU 1A, 2A as an electronic device.

CPU 1 built in each ECU 1A, 2A
In 1A and 12A, the priority when transmitting the response data in response to the diagnostic command and the timing of transmitting the response data are set according to the priority. Furthermore, each ECU 1
Since the transmission buffer TX and the reception buffer RX of A and 2A are commonly connected by the communication line L ₀ , the response data transmitted by itself and the response data transmitted by another ECU can be respectively received through the reception buffer RX. . Therefore, it is possible to confirm that the ECU having the higher priority has finished transmitting the response data.

Next, the operation of this embodiment will be described with reference to the timing chart of FIG. 2 and the flow charts of FIGS. In this embodiment, the CPU 31A and each ECU 1
The diagnostic command and response data transmitted / received between A and 2A will be described with the data format of a plurality of bytes shown in FIG. First, the CPU 31A transmits a diagnostic command in data units at intervals of T ₁ seconds from the communication line m ₀ to the connectors 41a, 41.
It is sent to the communication line L ₀ branched and connected to each ECU 1A, 2A via b. At this time, the time width T ₀ of the unit data is less than T ₁ second.

The diagnostic command is sent to each ECU via the communication line L _0.
1A, 2A receive buffer C via receive buffer RX
It is simultaneously received by the PUs 11A and 12A. CPU11
As shown in FIG. 3B, each of A and 12A has a built-in frilan timer which is always incremented by software. Then, when the timer output of the free run timer is read and it is determined that there is no data input for T ₁ second or more (time point A in FIG. 2), reception completion of the diagnostic command is confirmed.

After confirming the reception completion, if the CPU 11A of the ECU 1A, which is set to the first priority, reads the timer output and determines that T ₂ seconds have elapsed (T ₂ > T ₁ ), the time point of the circle B is reached. Then, the response data is sent to the communication line L ₀ at intervals of T ₁ seconds (T ₁ > T ₀ ) in the data unit of the time width T ₀ . The response data is received by the CPU 12A via the reception buffer RX of the ECU 2A commonly connected to the communication line L ₀ , and when it is confirmed that the top data of the response data has been transmitted, the transmission of its own response data is awaited. Go into action (Maru C
Point of time).

While waiting for data transmission, the CPU 1 of the ECU 2A
When 2A reads the timer output and confirms that no data is received for T ₁ second or more, it determines the end of transmission of response data by the ECU 1A. Further, when it is confirmed by the timer output that T ₃ seconds (T ₃ > T ₂ + T ₀ ) has elapsed, the response data is started to be transmitted for each unit data at intervals of T ₁ seconds from the time point of the circle D. The response data transmission start time is set according to the data transmission priority of the ECU.

On the other hand, the tester 310 that receives the response data.
CPU 31A inside reads out the timer output for T ₄ seconds (T ₄ >
After confirming that there is no data received for T ₃ ) or more, the ECU 1
The reception of all response data from A and 2A is judged (Maru E
Point of time).

Next, the CPU in each ECU 1A, 2A
The data communication processing of 11A and 12A will be described with reference to the flowchart of FIG. First, the CPU 11A determines whether or not the diagnostic command transmitted from the tester 31A has been received for each unit data (step S301). When the data reception is not judged, the timer output t of the free run timer which is always incremented in step S313
Is compared with the read data transmission interval time T ₁ (step S304), and when the timer output t ≦ T ₁ , it is determined that the data transmission cycle has not been reached, and the process returns to step S301 to wait for data reception.

If it is judged that the data has been received, the timer output is reset to 0 to prepare for the next unit data transmission time measurement (step S302), and the received data is saved in a predetermined storage area (step S303). After that, the processes of steps S301 to S304 are further repeated, and the data is saved each time the return unit data is received. While each process is being performed, the unit data is not received in step S304 and the timer output t
When it is determined that> T ₁ , it is determined that all the unit data forming the diagnostic command has been received, and it is determined whether the response command needs to be returned (step S
305).

At this time, if the CPU 11A determines that it is necessary to return the response data to the diagnostic command,
The timer output t is read and t and T _C (= T ₂ seconds: ECU1
In the case of A) (step S306), t ≧ T _C
If it is determined that the response data is transmitted, the response data transmission is started (step S309).

After transmitting the response data, the timer output t is reset to 0 (step S310), the response data transmitted by the ECU 2A is received by the reception buffer RX to monitor the data transmission, and the transmission of the response data by the ECU 2A is completed. Enter the judgment process. As the end determination process, the timer output t is read and compared with a preset T ₄ seconds (step S311), and if t ≧ T ₄ , it is determined that the transmission of all response data has ended.

However, during t <T ₄ , it is determined whether or not unit data is received (step S312). If not received, the process returns to step S311 to check whether or not unit data is received within T ₄ seconds. . When the unit data is received, the timer output is reset to 0 (step S310),
The process for determining the end of response data transmission is entered again. If it is determined in step S305 that the response data need not be returned, the process proceeds to response data end determination processing in steps S310 to 312.

It should be noted that the processing of the ECU 2 until the timer output t becomes equal to or more than T ₃ is merely the processing of determining whether or not its own reception buffer RX has received the unit data (step S307), and the response data Wait for sending.
When the unit data is received, the timer output t is reset to 0 to prepare for the data non-transmission time measurement (step S3).
08).

Next, the CPU 31A in the tester 310
The data communication process will be described with reference to the flowchart of FIG. First, data is read from the keyboard 31g to set a diagnostic command, and the command is changed if necessary (step S401). Then, after transmitting the diagnostic command (step S402), it is determined whether or not the response data is received from the ECU for each unit data (step S403). If the reception determination is made, the timer output t by the free-run timer is set to 0. Is reset to save the received data (steps S404 and 405).

When the unit data is not received, the unit data transmission interval time T ₁ is compared with the timer output t. When t ≦ T ₁ , the process returns to step S403 and the unit data reception is determined. Receive multiple unit data and receive t> T ₁
If it is determined that the error has occurred (step S406), the received response data is saved in a predetermined memory area and used as failure diagnosis data (step S407).

Next, after saving the response data, the timer output t is read, and t and T indicating the response data transmission end time are read.
_It is compared with ₄ (step S408). Comparison result t <T ₄
If so, it waits for the transmission of other response data, and step S4 is performed again.
The processes of 03 to 407 are repeated, and if t ≧ T ₄ , it is determined whether or not the response data is transmitted thereafter (step S
409). At this time, if it is determined that the response data has not been transmitted, no response is displayed on the display device 31e, and if it is determined that the response data has been transmitted, the response data is displayed on the display device 31e (step S411) for another failure diagnosis. In preparation, the process returns to step S401.

[0035]

As described above, according to the present invention, a single serial transmission line for transmitting and receiving information between a plurality of electronic devices and a diagnostic device that obtains fault diagnostic information from these electronic devices and performs fault diagnostics. In addition, each electronic device is provided with a priority order for transmitting the failure diagnosis information to the diagnosis device, and the failure diagnosis information of its own is transmitted through the serial transmission path with a time difference according to the priority order. By transmitting to the diagnostic device, the fault diagnostic information from a plurality of electronic devices can be continuously transmitted to the diagnostic device without collision on the transmission path, so that the fault diagnostic time as a whole is reduced. The effect is that it can be shortened.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of a failure diagnosis information communication device according to the present invention.

FIG. 2 is a timing chart illustrating a procedure for transmitting and receiving a diagnostic command and response data according to the present embodiment.

FIG. 3 is a flowchart illustrating a processing operation of the ECU according to the present embodiment.

FIG. 4 is a flowchart illustrating a processing operation of a tester according to this embodiment.

FIG. 5 is a diagram showing a data format of a diagnostic command and response data used in this embodiment and a conventional device.

FIG. 6 is a block diagram showing a configuration of a conventional failure diagnosis information communication device.

FIG. 7 is a timing chart illustrating a procedure of transmitting / receiving a diagnostic command and response data in a conventional device.

FIG. 8 is a flowchart illustrating a processing operation of a conventional tester.

FIG. 9 is a flowchart illustrating a processing operation of a conventional ECU.

[Explanation of symbols]

1A, 2A ECU 11A, 12A, 31A CPU L ₀ serial transmission line 310 tester

[Procedure amendment]

[Submission date] May 18, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction content]

Upon receiving the diagnostic command, the CPU 11 sends a preset response command from the transmission buffer TX via the communication line L ₁ to the CPU 31a of the tester 31 at the point of time D.
Send to. Each ECU1,2, the data format of the diagnostic command and response data communicated between ... 8 and the tester 31 are taken asynchronous SCI format of the 10-bit configuration as shown in Figure 5 (b). In the case of this data format, the effective data is 8 bits, and the 1st bit and the 10th bit indicate the start bit and the stop bit, respectively.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction content]

After transmitting the diagnostic command, the ECU waits for a response data from the ECU (step S805) . If no response is received, a constant cycle interrupt as shown in FIG.
Based on the incremented value of the software timer, it is determined whether the diagnostic command is received within the predetermined time (step S807). At this time, if it is determined that the response data is not received within the predetermined time, no response is displayed on the display device 31e (step S808). But step S
When it is determined in 805 that the response data from the ECU to be diagnosed is received, the response data is displayed on the display device 31e (step S806).

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction content]

Next, the ECU 1, which receives the diagnostic command,
The operation of the CPU built in 2, ... 8 will be described with reference to the flowchart of FIG. The CPU checks the level of the initialization signal while controlling various control target devices which are the original functions (steps S901 and 902). When it is determined that the signal level is the high level, the control process is continued without shifting to the communication process. However, when it is determined that the signal level is low level, the arrival of the diagnostic command transmitted from the tester 31 is waited for (step S903), and while the diagnostic command does not arrive, the time-out occurs in step S905.
Continue to wait until your decision . When the diagnostic command is received, diagnostic data corresponding to the command is transmitted to the tester 31 as response data (step S9).
04). After transmitting the response data, the process returns to step S901 and the control process is performed until the diagnostic command is received.

[Procedure amendment 4]

[Document name to be amended] Statement

[Name of item to be corrected] 0015

[Correction method] Change

[Correction content]

[0015] communication system and the tester and the ECU performs data transmission and reception is a point-to-point communication to transmit and receive data by selecting a communication line connected to the ECU is faulty diagnosed by the CPU side of the multiplexer Therefore, it is necessary to transmit a diagnostic command for each ECU when performing a failure diagnosis for a plurality of ECUs, and there is a problem that it takes a long time to complete the failure diagnosis for all the ECUs as a whole. It was

[Procedure Amendment 5]

[Document name to be amended] Statement

[Name of item to be corrected] 0022

[Correction method] Change

[Correction content]

The diagnostic command is sent to each ECU via the communication line L _0.
1A, 2A receive buffer C via receive buffer RX
It is simultaneously received by the PUs 11A and 12A. CPU11
A, flip over 12A is always increment operation as shown in FIGS 3 (b) run timer (hereinafter, Thailand
(Abbreviated as Ma) is built in software. And above
When it is determined that no data has been input for T ₁ second or more (time point A in FIG. 2) using the value of the timer, the completion of reception of the diagnostic command is confirmed.

[Procedure correction 6]

[Document name to be amended] Statement

[Name of item to be corrected] 0023

[Correction method] Change

[Correction content]

After confirmation of completion of reception, the CPU 11A of the ECU 1A, which is set to the first priority, uses the timer to set the T
If it is determined that ₂ seconds have elapsed (T ₂ > T ₁ ), the response data at the time of circle B is the data unit of the time width T ₀ at T ₁ second intervals (T ₁ > T ₀ ) at the communication line L _0. Send to. The response data is received by the CPU 12A via the reception buffer RX of the ECU 2A commonly connected to the communication line L ₀ , and when it is confirmed that the leading data of the response data has been transmitted, it waits for the transmission of its own response data. Enter the action (at the time of Maru C).

[Procedure Amendment 7]

[Document name to be amended] Statement

[Name of item to be corrected] 0024

[Correction method] Change

[Correction content]

While waiting for data transmission, the CPU 1 of the ECU 2A
2A determines termination of the transmission of the response data by ECU1A When confirming that the T data received over _a second free by the timer. Further more T ₃ seconds to the timer (T _3> T ₂ +
When it is confirmed that T ₀ ) has elapsed, the response data is started to be transmitted for each unit data at intervals of T ₁ seconds from the time point of circle D. still,
The response data transmission start time is set according to the data transmission priority of the ECU.

[Procedure Amendment 8]

[Document name to be amended] Statement

[Name of item to be corrected] 0025

[Correction method] Change

[Correction content]

On the other hand, the tester 310 that receives the response data.
The CPU 31A inside has a timer similar to the ECUIA and 2A.
When it is confirmed that no data has been received for T ₄ seconds (T ₄ > T ₃ ) or more, it is determined that all response data has been received from the ECUs 1A and 2A (at the time of circle E).

[Procedure Amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

Next, the CPU in each ECU 1A, 2A
The data communication processing of 11A and 12A will be described with reference to the flowchart of FIG. First, the CPU 11A determines whether or not the diagnostic command transmitted from the tester 31A has been received for each unit data (step S301). When the data reception is not determined, the value of the timer t which is always incremented in step S313 and the data transmission interval
Comparing the T ₁ (step S304), when the timer t ≦ T ₁ waits for data reception process returns to step S301 determines that not reached the data transmission period.

[Procedure Amendment 10]

[Document name to be amended] Statement

[Name of item to be corrected] 0027

[Correction method] Change

[Correction content]

If it is determined that the data has been received, the timer t is reset to 0 to prepare for the next unit data transmission time measurement (step S302), and the received data is saved in a predetermined storage area (step S303). After that, the processes of steps S301 to S304 are further repeated, and the data is saved each time the return unit data is received. In carrying out the process, timer not received the unit data in step S304 t> T
_If it is determined to be ₁ , it is determined that all unit data forming the diagnostic command has been received, and it is determined whether the response command needs to be returned (step S30).
5).

[Procedure Amendment 11]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction content]

At this time, if the CPU 11A determines that it is necessary to return the response data to the diagnostic command,
The value of the timer t and T _C (= T ₂ seconds: For ECU 1A) and compares (step S306), it starts to transmit the response data is determined is t ≧ T _C (step S3
09).

[Procedure Amendment 12]

[Document name to be amended] Statement

[Name of item to be corrected] 0029

[Correction method] Change

[Correction content]

[0029] After transmitting the response data, and resets the timer t to 0 (step S310), while monitoring the received and the data transmitted by the transmission reception response data buffer RX by ECU 2A, the transmission end of the response data by ECU 2A Enter the judgment process. This end determination process is
The value of mat is compared with the preset T ₄ seconds (step S3
11) If t ≧ T ₄ , it is determined that the transmission of all response data has ended.

[Procedure Amendment 13]

[Document name to be amended] Statement

[Name of item to be corrected] 0030

[Correction method] Change

[Correction content]

However, during t <T ₄ , it is determined whether or not unit data is received (step S312). If not received, the process returns to step S311 to check whether or not unit data is received within T ₄ seconds. . When the unit data is received, the timer t is reset to 0 (step S310), and the response data transmission end determination process is started again. Also step S
If it is determined in 305 that it is not necessary to return the response data, the process proceeds to the response data end determination processing in steps S310 to 312.

[Procedure Amendment 14]

[Document name to be amended] Statement

[Correction target item name] 0031

[Correction method] Change

[Correction content]

[0031] In addition, EC until the timer t becomes T ₃ or more
The process of U2 is merely the process of determining whether or not its own reception buffer RX has received the unit data (step S307), and waits for the transmission of response data. Further Upon receiving the unit data comprises the resetting of the timer t is 0 no-data transmission time measurement (step S308).

[Procedure Amendment 15]

[Document name to be amended] Statement

[Name of item to be corrected] 0032

[Correction method] Change

[Correction content]

Next, the CPU 31A in the tester 310
The data communication process will be described with reference to the flowchart of FIG. First, data is read from the keyboard 31g to set a diagnostic command, and the command is changed if necessary (step S401). After transmitting the diagnostic command (step S402), it is determined whether or not the response data is received from the ECU for each unit data (step S403). If the reception determination is made, the ECUI
Ties that are constantly incremented as in A and 2A
The Ma t is reset to 0 to retract the received data (step S404,405).

[Procedure Amendment 16]

[Document name to be amended] Statement

[Correction target item name] 0033

[Correction method] Change

[Correction content]

[0033] However, t ≦ compares the unit data transmission interval time T ₁ and the timer t when the unit data is not received
When it is T _1, the process returns to step S403, and the unit data reception determination is performed. When a plurality of unit data are received and it is determined that t> T ₁ is satisfied (step S406), the received response data is saved in a predetermined memory area and used as failure diagnosis data (step S407).

[Procedure Amendment 17]

[Document name to be amended] Statement

[Correction target item name] 0034

[Correction method] Change

[Correction content]

[0034] Next, timer t After saving the response data
Reading, compared with T ₄ showing a t the response data transmission end time (step S408). If the comparison result is t <T ₄ , the transmission of other response data is waited for again in step S40.
The processes of 3 to 407 are repeated, and if t ≧ T ₄ , it is determined whether or not the response data is transmitted thereafter (step S4).
09). At this time, if it is determined that the response data has not been transmitted, no response is displayed on the display device 31e, and if it is determined that the response data has been transmitted, the response data is displayed on the display device 31e (step S411) for another failure diagnosis. In preparation, the process returns to step S401.

[Procedure 18]

[Document name to be corrected] Drawing

[Correction target item name] Figure 9

[Correction method] Change

[Correction content]

[Figure 9]

Claims (1)

[Claims] 1. A single serial transmission line for transmitting and receiving information is provided between a plurality of electronic devices and a diagnostic device for performing failure diagnosis by obtaining failure diagnosis information from these electronic devices, and each of the electronic devices is provided with: The priority order for transmitting the failure diagnosis information to the diagnosis apparatus is set, and the failure diagnosis information of its own is transmitted to the diagnosis apparatus through the serial transmission path with a time difference according to the priority order. A fault diagnosis information communication device.