JP6569407B2 - Master communication device and slave communication device - Google Patents

Description

  The present invention relates to a master-slave communication technique in which a slave communication device outputs data in response to a command from a master communication device.

  Conventionally, in a master communication device and a slave communication device that perform communication by a master / slave method, a technique for preventing the master communication device from receiving data output from the slave communication device in which an abnormality has occurred at least other slave communication devices It has been known.

  In Patent Literature 1, when there is no data transmission by the slave communication device in response to a command from the master communication device, an error has occurred in the slave communication device without transmission, and the command from the master communication device to the slave communication device Has been disclosed.

JP 2007-312043 A

  By the way, in the technique described in Patent Document 1, the slave communication device transmits data in response to a command transmitted from the master communication device. In recent years, there has been a request from the user to actively transmit data from the slave communication device even when a command from the master communication device is not transmitted to such a slave communication device.

  Therefore, even when a command is not transmitted from the master communication device, for example, when a predetermined event occurs in the slave communication device, a new master-slave method capable of actively transmitting data from the slave communication device Communication technology is considered.

  However, in the master-slave communication technology that can actively transmit data from the slave communication device, if an error occurs in the slave communication device, the data output from the slave communication device in which the error has occurred is transferred to another slave When received by the communication device, for example, there is a risk of erroneous control based on the data.

  The present invention provides a technique for suppressing data transmitted from a slave communication device in which an abnormality has occurred in a master communication device and a slave communication device that perform communication using a master / slave communication method from being used by another slave communication device. It is intended to provide.

  One aspect of the present invention is a master communication device, and the master communication device is communicably connected to a plurality of slave communication devices via a bus. The master communication device includes specific information acquisition means and discard information transmission means. The specific information acquisition means transmits data according to a transmission command indicating a command in which a device to which data is to be transmitted by the master communication device is specified, and even if there is no transmission command from the master communication device A communication device that transmits data when a preset transmission condition is satisfied is set as a slave communication device, and specific information that can identify which slave communication device among the plurality of slave communication devices has an abnormality is acquired. The discard information transmission means transmits at least the discard information for causing the abnormal device representing the slave communication device in which the abnormality has occurred to discard data that is a transmission source to at least a slave communication device other than the abnormal device based on the specific information. .

  According to the master communication device having such a configuration, the normal slave communication device is made to discard the data originating from the abnormal slave communication device, so that the data is prevented from being used by other slave communication devices. can do. As a result, it is possible to suppress erroneous control or the like on a normal slave communication device based on the data.

  Another aspect of the present invention is a slave communication device, which includes a master communication device and one or more other slave communication devices as communication partners, and should transmit data by the master communication device. The device transmits data in response to a transmission command representing a designated command, and transmits data when a preset transmission condition is satisfied even when there is no transmission command from the master communication device. The slave communication device includes discard information receiving means and data discarding means. The discard information receiving unit receives, from the master communication device, discard information for discarding data that is the transmission source of the abnormal device representing the slave communication device in which the abnormality occurred among the other slave communication devices. The data discarding unit is configured to discard the data that is the source of the abnormal device based on the discard information.

  According to the slave communication device having such a configuration, data that originates from an abnormal slave communication device is discarded based on the discard information, and thus an erroneous control or the like based on the data is performed in a normal slave communication device. This can be suppressed.

  In addition, the code | symbol in the parenthesis described in the claim shows the correspondence with the specific means as described in embodiment mentioned later as one aspect, Comprising: The technical scope of this invention is limited is not.

The block diagram which shows the structure of a communication system, a master communication apparatus, and a slave communication apparatus. The figure which shows an example of a structure of the communication frame used for communication with a master and a slave. The figure which shows an example of the schedule table when abnormality has not generate | occur | produced in the slave. (A) is a figure which shows an example of the correspondence management table of a master, (b) is a figure which shows an example of the correspondence management table of a slave 3a. The figure which shows an example of operation | movement of a master and a slave. The flowchart of the master regular process of 1st Embodiment. The flowchart of an excess wakeup detection process. The flowchart of a sleep prohibition continuation detection process. The flowchart of the slave regular process of 1st Embodiment. The figure which shows a mode that an abnormality flag is set to an abnormal node. The flowchart of the master regular process of 2nd Embodiment. The figure which shows an example of a new schedule table. The flowchart of the slave regular process of 2nd Embodiment. The flowchart of a frame breakage detection process.

Embodiments to which the present invention is applied will be described below with reference to the drawings.
[1. First Embodiment]
[1-1. Constitution]
[1-1-1. overall structure]
A communication system 1 shown in FIG. 1 is a system mounted on a vehicle, and includes a master node (hereinafter simply referred to as a master) 2 as a communication device (node) and three slave nodes (hereinafter simply referred to as slaves) 3. With. Each of these nodes is communicably connected to each other via the bus 5. Although there are three slave nodes in the present embodiment, any number of slave nodes may be used. In the following, when the three slaves 3 are described separately, 3a, 3b, and 3c are used as symbols.

First, the configuration of the master 2 will be described. The master 2 includes a transceiver 23 and a control unit 21.
The transceiver 23 is a well-known communication module that includes a circuit and transmits and receives data via the bus 5. That is, the transceiver 23 outputs the data supplied from the control unit 21 to the bus 5 and supplies the data input from the bus 5 to the control unit 21.

The control unit 21 includes a known microcomputer having a CPU 211, a ROM 212, a RAM 213, and the like.
The CPU 211 executes processing that realizes various functions for controlling the vehicle, such as control of the body system and the engine system, by executing programs recorded in the ROM 212 and the RAM 213, for example.

Specifically, the control unit 21 implements various functions for controlling the vehicle based on communication with the slave 3.
Here, a communication frame used for communication between the master 2 and the slave 3 will be described with reference to FIG. Hereinafter, the communication frame is simply referred to as a frame. A frame is composed of a header and a response.

The header is basically transmitted from the master 2 according to a schedule table described later.
However, when an event described later occurs, it is also transmitted from the slave 3 corresponding to the event.

  The header is an identification number represented by 8 bits unique to each frame, and is a number designating a node to which a response is to be transmitted. That is, based on the header, it is possible to identify a node that is permitted to transmit a response (hereinafter referred to as a response node). In the present embodiment, the header can designate the slave 3 and the own master 2 as response nodes.

  The response is basically transmitted from the slave 3 or the master 2 specified by the header transmitted from the master 2 according to the schedule table. However, when an event occurs, the response may be transmitted from the slave 3 specified by the header transmitted by the slave 3 corresponding to the event. The slave 3 corresponding to the event may specify its own slave 3 (slave 3 corresponding to the event) as a response node, or may specify another slave 3 as a response node. In the present embodiment, an example in which the own slave 3 is designated as a response node when an event occurs will be described.

  Hereinafter, a frame composed of a header transmitted by the master 2 according to the schedule table and a response corresponding to the header is referred to as a regular frame. A frame composed of a header and a response transmitted by the slave 3 corresponding to the event when the event occurs is referred to as an event frame.

The response consists of a frame information part and a data part. The frame information portion includes at least 1-bit wakeup pulse transmission information and 1-bit sleep availability information.
The wakeup pulse transmission information is information indicating whether or not a wakeup pulse has been transmitted. The wake-up pulse transmission information is set to 1 when the node that has transmitted the response including the wake-up pulse transmission information transmits a wake-up pulse, and is set to 0 when the node does not transmit. Hereinafter, the wakeup pulse transmission information is referred to as WUP transmission information.

  The sleep availability information is information indicating whether or not it is possible to transition to the sleep state. The sleep propriety information is set to 1 when the node that has transmitted the response including the sleep propriety information is permitted to sleep, and is set to 0 when the node is not permitted.

The data part includes data of a type designated in advance for each header.
Returning to FIG. 1, the description will be continued. The control unit 21 (CPU 211) executes, for example, regular transmission processing, regular reception processing, and master regular processing.

  The periodic transmission process is a process of periodically transmitting a transmission command according to a schedule table that is a preset schedule. The transmission command is a command for designating the slave 3 to the slave 3 device to which data is to be transmitted, and corresponds to the above-described header. The data here corresponds to the response described above. In other words, the periodic transmission process is a process of periodically transmitting the header according to the schedule table.

As shown in FIG. 3 as an example, the schedule table ST ₀ includes transmission order information indicating the transmission order of the header, frame name information indicating the name of the frame including the header, and a response node indicating the response node corresponding to the header. The correspondence between the information and the request transmission interval information indicating the transmission interval of the header is set. The header transmission interval is a transmission interval from when a header is transmitted to when the next header is transmitted.

The schedule table ST ₀ is set to transmit a header (first) having the master 2 as a response node. The schedule table ST ₀ is set to transmit a header (second) having the slave 3 a as a response node after 1000 ms has elapsed since the transmission of the first header.

The schedule table ST ₀ transmits a header (third) having the slave 3a as a response node after 2000 ms has passed since the transmission of the second header, and 1000 ms has passed since the transmission of the third header. It is set to transmit a header (fourth) having the master 2 as a response node later.

Similarly, the schedule table ST ₀ transmits a header (fifth) having the slave 3b as a response node after 500 ms has elapsed, and similarly transmits a header (sixth) having the slave 3c as a response node after 500 ms has elapsed. It is set to be.

The schedule table ST ₀ is set to transmit a header (first) having the master 2 as a response node after 1000 ms has passed since the sixth header was transmitted.

Subscribe process is a process of receiving a response corresponding to the regularly transmitted header according to the schedule table ST _0. Based on the received response, the control unit 21 performs processing for realizing various functions for controlling the vehicle, using data included in the response data unit.

  The master periodic process is a process for preventing an event frame having the slave 3 in which an abnormality has occurred as a response node from being used by other normal nodes when an abnormality occurs in the slave 3. Details of the master periodic process will be described later.

Returning to FIG. The ROM 212 records a schedule table ST ₀ , node identification number, correspondence management table KT ₀ (see FIG. 4A), etc., in addition to programs for executing the above-described processing.

The node identification number is an identification number assigned to each of the master 2 and the slave 3 so that each can be identified.
The correspondence management table KT ₀ is a table showing the relationship between headers and response nodes for all periodic frames and event frames used in communication with the slave 3.

As shown in FIG. 4A as an example, the correspondence management table KT ₀ includes a header, frame name information indicating the name of the frame including the header, response node information indicating the response node corresponding to the header, A correspondence relationship with type information indicating the type of frame or event frame is set.

Specifically, the correspondence management table KT ₀ sets a header of 0x01 as the frame name is A1, the response node is the master 2, and it is a periodic frame.
The correspondence management table KT ₀ sets the header 0x05, the frame name is C1, the response node is the slave 3b, and is a regular frame, the header 0x06 is the frame name C2, and the response The node is the slave 3b and is set to be an event frame.

That is, the correspondence management table KT ₀ is set so that only the slave 3b and the slave 3c can transmit event frames. In the following, a frame with the frame name A1 is simply described as a frame A1.

Next, returning to FIG. 1, the configuration of the slave 3 will be described.
The slave 3 includes a transceiver 33, a control unit 31, and a switch 7.
The transceiver 33 is a communication module similar to the transceiver 23 included in the master 2, outputs data supplied from the control unit 31 to the bus 5, and supplies data input from the bus 5 to the control unit 31. .

  The switch 7 is connected to the control unit 31 and outputs an event signal to the control unit 31 when a preset event such as unlocking or locking of a door lock, movement of an electric seat, or the like occurs. To do.

  The control unit 31 includes a known microcomputer having a CPU 311, a ROM 312, a RAM 313, and the like. The CPU 311 performs processing for realizing various functions assigned in advance by executing programs recorded in the ROM 312 and the RAM 313.

  For example, when the master 2 performs control of the body system, the slave 3 performs control related to the door, such as door locking and unlocking, power window control, air conditioner control, electric seat control, etc. Processing for realizing various functions assigned in advance is performed.

Specifically, the control unit 31 includes the master 2 and one or more other slaves 3 as communication partners, and realizes various functions based on communication with these communication partners.
For example, the control unit 31 executes response transmission processing, frame reception processing, event frame transmission processing, and slave periodic processing.

The response transmission process is a process of transmitting a response according to a header that designates the slave 3 that is the own node as a response node.
The frame reception process is a process that, when receiving a header having its own node as a receiving node, captures a response transmitted after the header and implements various functions using the captured frame (response). The receiving node refers to a node that takes in a header and a response transmitted subsequent to the header.

Whether or not the received header uses the own node as the receiving node is determined based on a correspondence management table described later.
The event frame transmission process is a process for transmitting an event frame when a preset transmission condition is satisfied. The time when the preset transmission condition is satisfied means when an event signal is output from the switch 7, that is, when a preset event occurs.

  The event frame transmitted by the slave 3 in response to the occurrence of such an event is a frame in which the other slave 3 related to the event is a receiving node, and the control for controlling the other slave 3 in the data part Contains data.

  The slave periodic process is a process for preventing an event frame transmitted from another slave 3 in which an abnormality has occurred from being used in a normal node when an abnormality has occurred in another slave 3. Details of the slave periodic processing will be described later.

The ROM 312 records a node identification number, a correspondence management table KT ₁ (see FIG. 4B), and the like in addition to the program for executing the above-described processing.
However, correspondence management table KT ₁ of the slave 3 is different from the correspondence management table KT ₀ of the master 2, a table only periodic frames and event frame the own node transceiver is shown.

As shown as an example in FIG. 4 (b), the management table KT ₁ slave 3a, header specifying the slave 3a is a self node as a response node is only 0x03 and 0x04. That is, for the slave 3a, based on the correspondence management table KT _1, header other than 0x03 and 0x04 is determined to be the header to the receiving node to the own node (slave 3a).

[1-1-2. Operational state]
Next, operation states of the master 2 and the slave 3 will be described.
In the master 2, the control unit 21 performs a process of changing the operation state as the master 2 between the wake-up state and the sleep state. In the slave 3, the control unit 31 also performs a process of changing the operation state as the slave 3 between the wake-up state and the sleep state, similarly to the control unit 21. For this reason, below, the operation state about the master 2 is demonstrated. However, in the description, the corresponding configuration in the slave 3 is described in parentheses.

  The wake-up state is a normal operation state in which all functions assigned in advance to the master 2 (slave 3) can be executed. The sleep state is assigned in advance to the master 2 (slave 3) in order to reduce power consumption. This is an operation state in which some of the received functions are stopped.

  Specifically, the control unit 21 (control unit 31) wakes up when a predetermined wake-up factor occurs in the master 2 (slave 3) as its own node in the sleep state. A wakeup pulse is transmitted to 5. Wake-up refers to setting the operating state from the sleep state to the wake-up state. The wake-up pulse is a signal that can wake up all the nodes that have received the wake-up pulse. That is, even when the control unit 21 (control unit 31) receives a wake-up pulse from another node via the bus 5, it can wake up.

[1-1-3. Example of master and slave operation]
Next, an example of the operation of the master 2 and the slave 3 will be described. Here, an example of normal operation will be described. The normal time means a time when there is no abnormality in the slave 3.

The master 2 transmits headers in order according to the schedule table ST ₀ (periodic transmission processing).
The slave 3 transmits a response when the header transmitted by the master 2 designates its own node as a response note (response transmission processing).

That is, as shown in FIG. 5, the bus 5, according to the schedule table ST _0, the frame A1, B1, b2, A2, C1, D1 is, in turn, is repeatedly output.
However, when a preset event occurs in the slave 3c or the slave 3b, the slave 3c or the slave 3b in which the event has occurred transmits an event frame.

[1-1-4. Abnormal node detection]
By the way, if any abnormality occurs in the slave 3 that transmitted the event frame, there is a possibility that the event frame has an abnormality. If there is an abnormality in the event frame, there may be a problem that another normal slave 3 that has taken in the event frame in which the abnormality has occurred performs erroneous control using the event frame. There is.

  Therefore, in the communication system 1, the master 2 and the slave 3 do not use the event frame transmitted from the slave 3 in which the abnormality occurs in the normal slave 3 when any of the slaves 3 is abnormal. In order to achieve this, master regular processing and slave regular processing are executed, respectively. Hereinafter, the slave 3 in which an abnormality has occurred is referred to as an abnormal node.

[1-2. processing]
[1-2-1. Master periodic processing]
The master regular process which the master 2 (control part 21) performs is demonstrated using the flowchart of FIG. The master periodic process is repeatedly executed at a predetermined cycle while the power of the master 2 is turned on (for example, while the ACC switch is turned on). The master regular process executes a regular transmission process, identifies a slave 3 in which an abnormality has occurred, and prevents an event frame transmitted from the slave 3 in which an abnormality has occurred from being used by another normal slave 3 It is.

In addition, when the subject is abbreviate | omitted in the following explanatory note, the control part 21 (CPU211) is made into a subject.
First, in S (step) 110, an excessive wakeup detection process is executed. The excessive wakeup detection process is a process for identifying an abnormal node based on WUP transmission information included in a response transmitted by the slave 3.

  Next, in S115, a sleep prohibition continuation detection process is executed. The sleep prohibition continuation detection process is a process for identifying an abnormal node based on the sleep availability information included in the response transmitted by the slave 3.

  In subsequent S120, it is determined whether or not an abnormal node has occurred. Specifically, when an abnormal node is specified in the excessive wakeup detection process or the sleep prohibition continuation detection process, it is determined that an abnormal node has occurred. If an abnormal node has not occurred, the process proceeds to S125. If an abnormal node has occurred, the process proceeds to S145.

In S125, it is determined whether the sleep condition is satisfied. Here, as an example, it is determined that the sleep condition is satisfied when the sleep enable / disable information in all the frames for one turn shown in the schedule table ST ₀ indicates sleep permission. If the sleep condition is not satisfied, the process proceeds to S130, and if the sleep condition is satisfied, the process proceeds to S135.

In S130 the sleep condition at S125 is shifted when it is determined not to be satisfied, to perform periodic transmission process of transmitting the header according to the schedule table ST _0. Then, the master regular process is terminated.

  In S135, which is shifted to when it is determined in S125 that the sleep condition is satisfied, a sleep frame is transmitted. The sleep frame is a frame transmitted by the master 2 (the control unit 21) in order to shift all the slaves 3 connected to the bus 5 to the sleep state.

In subsequent S140, the operation state of the master 2 is changed from the wake-up state to the sleep state. Then, the master regular process is terminated.
In S145, where it is determined that an abnormal node has occurred in S120 and the process proceeds to S145, a setting is made to discard the frame having the abnormal node as a response node and the event frame of the abnormal node. Specifically, based on the correspondence management table KT ₀ , a header having an abnormal node as a response node and an event frame header of the abnormal node are specified, and the specified header is recorded in the RAM 213.

  As a result, the control unit 21 can discard the frame having the abnormal node as the response node and the event frame of the abnormal node based on the header recorded in the RAM 213.

  In subsequent S150, an error notification frame is transmitted to the bus 5, and the master regular processing is terminated. The error notification frame is not described in the correspondence management table shown in FIG. 4, but is a frame in which all the slaves 3 are receiving nodes. The error notification frame includes the node identification number of the abnormal node in the data portion. The node identification number of the abnormal node corresponds to the identification information in the claims.

  That is, in the master regular process, the regular transmission process is executed when no abnormal node has occurred and the sleep condition is not satisfied (S130). Further, when no abnormal node has occurred and the sleep condition is satisfied, the master 2 and the slave 3 are shifted to the sleep state (S135, S140). If an abnormal node has occurred, an error notification frame is output (S150).

Next, the excessive wakeup detection process executed in S110 of the master regular process will be described with reference to the flowchart of FIG.
The excessive wakeup detection processing is performed based on the WUP transmission information included in the response transmitted from the slave 3, and the number of wakeup pulses equal to or greater than a predetermined wakeup threshold within a monitoring period that is a predetermined period. This is processing for identifying the transmitted slave 3 as an abnormal node.

  In the excessive wakeup detection process, the process shown in the flowchart of FIG. 7 is executed for all the slaves 3a, 3b, and 3c that are communicably connected to the master 2. That is, the description of “slave x” in the flowchart of FIG. 7 is replaced with each of the slaves 3a, 3b, and 3c. Hereinafter, a case where “slave x” is the slave 3a will be described.

  In S210, it is determined whether or not a monitoring time, which is a predetermined time, has elapsed since the master 2 was turned on. Although not shown, the control unit 21 executes a process of measuring an elapsed time after the master 2 is turned on as a process separate from the excessive wakeup detection process. To get. When the elapsed time is equal to or longer than the monitoring time, it is determined that the monitoring time has elapsed.

The monitoring time is set to about several hours as an example. However, the monitoring time may be arbitrarily set according to the communication system 1.
If it is determined that the monitoring time has elapsed, the process proceeds to S215. If it is determined that the monitoring time has not elapsed, the process proceeds to S220.

  In S215, which is shifted to when it is determined in S210 that the monitoring time has elapsed, the number of wakeups of all the slaves 3a to 3c is initialized. That is, 0 is substituted as the value of the number of wakeups.

In S220, which is shifted to when it is determined in S210 that the monitoring time has elapsed, it is determined whether or not a wake-up pulse has been received.
If it is determined that the wake-up pulse has not been received, the excessive wake-up detection process is terminated. If it is determined that the wake-up pulse has been received, the process proceeds to S225.

In S225, the response of the slave 3a is confirmed. Specifically, the WUP transmission information included in the response is acquired.
In S230, it is determined whether or not the slave 3a has transmitted a wakeup pulse. Specifically, when the value of the WUP transmission information is 1, it is determined that the slave 3a has transmitted a wakeup pulse. When the slave 3a has not transmitted the wakeup pulse, the excessive wakeup detection process is terminated. When the slave 3a has transmitted the wakeup pulse, the process proceeds to S235.

In S235, the number of wakeups of the slave 3a is counted up, that is, the number of wakeups is increased by one.
In S240, it is determined whether or not the number of wakeups of the slave 3a is equal to or greater than a wakeup threshold that is a predetermined threshold. When the number of wakeups of the slave 3a is less than the wakeup threshold, the excessive wakeup detection process is terminated, and when it is equal to or greater than the wakeup threshold, the process proceeds to S245.

  The wakeup threshold is set to a value that greatly exceeds the number of wakeups when the slave 3a is normal in order to detect an abnormality of the slave 3a. The wake-up threshold value may be set to an appropriate value according to the communication system 1.

In S245, the slave 3a is recorded in the RAM 213 as an abnormal node. Then, the excessive wakeup detection process ends.
The control unit 21 sets the slave 3b and the slave 3c as the slave x, performs the same process for the slave 3b and the slave 3c, and then returns the process to the master regular process.

Next, the sleep prohibition continuation detection process executed in S115 of the master regular process will be described with reference to the flowchart of FIG.
The sleep prohibition continuation detection process is a process for identifying, as an abnormal node, the slave 3 whose sleep is prohibited for a continuation period that is a predetermined period based on the sleep availability information included in the response transmitted from the slave 3. is there.

  The sleep prohibition continuation detection process is a process executed for all the slaves 3a, 3b, and 3c that are communicably connected to the master 2, similarly to the excessive wakeup detection process. That is, the description of “slave x” in the flowchart of FIG. 8 is replaced with each of the slaves 3a, 3b, and 3c. Hereinafter, a case where “slave x” is the slave 3a will be described.

In S310, the response of the slave 3a is confirmed. Specifically, sleep availability information included in the response is acquired.
In S315, it is determined whether or not the slave 3a is permitted to sleep. Specifically, when the value of the sleep availability information is 1, it is determined that the slave 3a is allowed to sleep. If the slave 3a is permitted to sleep, the process proceeds to S335, and if not permitted, the process proceeds to S320.

  In S320, when it is determined in S315 that the slave 3a is not permitted to sleep (sleep prohibition), it is determined whether or not the sleep prohibit timer of the slave 3a is stopped. The sleep prohibition timer is a process executed by the control unit 21 as a process separate from the sleep prohibition continuation detection process, and is a process of measuring a sleep prohibition continuation time which is a duration in which the slave 3a is set to sleep prohibition. .

If the sleep prohibit timer of the slave 3a is stopped, the process proceeds to S330, and if it is in operation, the process proceeds to S325.
In S325, where it is determined in S320 that the sleep prohibition timer of the slave 3a is operating, the process of the sleep prohibition timer of the slave 3a is continued. Then, the process proceeds to S340.

  In S320, when it is determined that the sleep prohibition timer of the slave 3a is stopped in S320, the process of the sleep prohibition timer of the slave 3a is started. Then, the process proceeds to S340.

  In S335, which is shifted when it is determined in S315 that the slave 3a is permitted to sleep, the sleep prohibition timer of the slave 3a is stopped, and the sleep prohibition duration that is a measurement value by the sleep prohibition timer is initialized. That is, the sleep prohibition duration is set to zero. Then, the process proceeds to S340.

  In S340, it is determined whether the sleep prohibition duration of the slave 3a is equal to or greater than a continuation threshold that is a predetermined threshold. If the sleep prohibition continuation time of the slave 3a is less than the continuation threshold, the sleep prohibition continuation detection process is terminated, and if it is greater than or equal to the continuation threshold, the process proceeds to S345.

  The continuation threshold is set to a value that greatly exceeds the sleep prohibition continuation time when the slave 3a is normal in order to detect an abnormality of the slave 3a. The continuation threshold may be set to an appropriate value according to the communication system 1.

In S345, the slave 3a is recorded in the RAM 213 as an abnormal node.
The control unit 21 sets the slave 3b and the slave 3c as the slave x, performs the same process for the slave 3b and the slave 3c, and then returns the process to the master regular process.

[1-2-2. Slave periodic processing]
Next, slave regular processing, which is processing performed by the slave 3 (control unit 31), will be described with reference to the flowchart of FIG. The slave periodic process is repeatedly executed at a predetermined cycle while the power supply of the slave 3 is turned on (for example, while the ACC switch is turned on). The slave periodic process is a process for discarding an event frame having the abnormal node as a transmission source while executing a frame reception process. Hereinafter, the slave 3a will be described as an example.

In addition, when the subject is abbreviate | omitted in the following explanatory note, the control part 31 (CPU311) is made into a subject.
In S400, it is determined whether or not an error notification frame as discard information has been received. The discard information is information transmitted from the master 2 and transmitted by an abnormal node that is a slave 3 other than the slave 3a that is the own node and has an abnormality among other slaves 3 (slave 3b and 3c). Information used to destroy the original data. If an error notification frame is received, the process proceeds to S420. If not received, the process proceeds to S430.

  In S420, which is shifted to when the error notification frame that is the discard information is received in S400, a setting is made to discard the event frame that is data having the abnormal node as the response node based on the error notification frame.

  Specifically, the slave 3 that is an abnormal node is identified based on the node identification number included in the error notification frame. For example, if the slave 3b is specified as an abnormal node, an abnormal flag for the slave 3b is set as shown in FIG. 10 as an example. The abnormality flag is a flag indicating that it is an abnormal node when set.

Then, based on the correspondence management table KT ₁ , a header having an abnormal node as a response node is specified, and the specified header is recorded in the RAM 313.
In S430, when the error notification frame is not received in S400, it is determined whether or not the received frame is to be discarded. Specifically, when the header of the received frame is recorded in the RAM 313 as being a header having an abnormal node as a response node in S420 before the current cycle, it is determined to be a discard target. If the received frame is to be discarded, the process proceeds to S435, and if not, the process proceeds to S440.

In S435, which shifts to the case where the received frame is to be discarded, the received frame is discarded, and this slave periodic processing ends.
In S440, which is shifted when the received frame is not a discard target, it is determined whether or not the received frame is a sleep frame. If it is not a sleep frame, the process proceeds to S450. If it is a sleep frame, the process proceeds to S460.

In S450, which is shifted when it is determined in S440 that the frame is not a sleep frame, frame reception processing is executed, and this slave periodic task is terminated.
In S460, which is shifted when it is determined in S440 that the frame is a sleep frame, the local node is shifted to the sleep state, and this slave periodic task is terminated.

  Next, an example of the operation of the master 2 and the slave 3 configured as described above will be described. The master 2 and the slave 3 operate as follows, for example, based on specific information that is information that can specify which of the slaves 3 is abnormal, that is, sleep availability information and WUP transmission information.

  When the slave 3b does not permit sleep for more than the continuation threshold, the master 2 transmits to the bus 5 an error notification frame that identifies the slave 3b as an abnormal node. As a result, after the error notification frame is transmitted, the event frame transmitted by the slave 3b, which is an abnormal node, is discarded in the master 2, the slave 3a, and the slave 3c, and the event frame is not received (see FIG. 4). .

  For example, when the number of wakeups, which is the number of times the wakeup pulse is transmitted in the slave 3b, is equal to or greater than the wakeup threshold, the slave 3b, which is an abnormal node, similarly transmits in the master 2 and the slaves 3a, 3c. The event frame is discarded and the event frame is not received.

The master 2 and the slave 3 configured as described above operate as follows.
The master 2 sets, as an abnormal node, the slave 3 that transmits a wakeup pulse more frequently than normal or the slave 3 that does not allow the sleep of its own node for a longer period than normal. Identify. As an example, FIG. 5 shows an example in which the slave 3b continues a period in which the slave 3b is not allowed to sleep for a longer period than normal. In the case of FIG. 5, the master 2 specifies the slave 3b as an abnormal node.

  The master 2 transmits an error notification frame so that the normal slave 3 other than the abnormal node (slave 3b in FIG. 5) discards the event frame transmitted from the abnormal node. It can be said that the error notification frame is a frame for causing a normal slave 3 to discard a frame having an abnormal node as a response node.

  The slave 3 (slave 3a, 3c in FIG. 5), which is a normal slave 3, discards an event frame having the slave 3b, which is an abnormal node, as a response node in response to the operation of the master 2 that transmits an error notification frame.

[1-3. effect]
According to the first embodiment described in detail above, the following effects can be obtained.
[1A] The master 2 (control unit 21) causes at least a normal slave 3 to discard an event frame having an abnormal node as a response node. According to this, it is possible to suppress an event frame having an abnormal node as a response node from being used by another normal slave 3. As a result, it is possible to suppress erroneous control or the like on other normal slaves 3 based on an event frame having an abnormal node as a response node.

  [1B] Specifically, the master 2 (the control unit 21) transmits an error notification frame including a node identification number that is information that can identify an abnormal node. According to this, since it is not necessary to provide a means for identifying an abnormal node on the slave 3 side, the slave 3 (control unit 31) can be simply configured.

  [1C] Master 2 (control unit 21) uses WUP transmission information as specific information. According to this, the slave 3 which is in the state which prevents the power-saving of the communication system 1 by transmitting a wakeup pulse frequently can be specified as an abnormal node.

  [1D] The master 2 (control unit 21) uses the sleep availability information as specific information. According to this, it is possible to identify the slave 3 that is in a state that hinders the power saving of the communication system 1 due to the continuation of the period in which sleep is not permitted, as an abnormal node.

  [1E] The slave 3 (control unit 31) discards the event frame having the abnormal node as the transmission source (response node). According to this, it is possible to suppress erroneous control or the like based on the event frame having the abnormal node as the transmission source in the normal slave 3.

  [1F] The slave 3 discards the event frame transmitted from the abnormal node based on the error notification frame including the node identification number that is information that can identify the abnormal node. According to this, since the abnormal node can be identified easily, the slave 3 (control unit 31) can be configured easily.

  In the first embodiment, the master 2 corresponds to an example of a master communication device, and the slave 3 corresponds to an example of a slave communication device. Further, the control unit 21 corresponds to an example of specific information acquisition means and discard information transmission means, S110 and S115 correspond to an example of processing as specific information acquisition means, and S150 corresponds to an example of processing as discard information transmission means. It corresponds to an example.

  The control unit 31 corresponds to an example of a discard information receiving unit and a data discard unit, S400 corresponds to an example of a process as a discard information receiving unit, and S420 corresponds to an example of a process as a data discard unit. Further, the UWP transmission information and the sleep availability information correspond to an example as specific information, and the abnormality notification frame corresponds to an example of discard information.

[2. Second Embodiment]
[2-1. Difference from the first embodiment]
Since the basic configuration of the second embodiment is the same as that of the first embodiment, the description of the common configuration will be omitted, and the description will focus on the differences.

  In the first embodiment described above, the master 2 uses the error notification frame as discard information that is information for discarding an event frame in which the slave 3 that has failed in the normal slave 3 becomes a response node (source). sent.

  On the other hand, in the second embodiment, for the slave 3 having a function of recognizing that the slave 3 whose header is not transmitted from the master 2 is an abnormal node, as the discard information, only the slave 3 other than the abnormal node is received. It differs from the first embodiment in that a header for transmitting a response is transmitted.

  Note that this difference is different from the flowchart shown in FIG. 6 in that S150 is replaced with S160 in the master periodic process (FIG. 11) executed by the master 2 of the present embodiment. Further, in the slave regular processing (FIG. 13) executed by the slave 3 of the present embodiment, S405, S415, and S425 are added to the flowchart shown in FIG. 9, and S400 is replaced with S410.

[2-2. processing]
[2-2-1. Process executed by master]
In the present embodiment, the master regular processing executed by the master 2 (control unit 21) will be described with reference to the flowchart of FIG.

  Since the control unit 21 performs the same processing as in the first embodiment except for S160, when an abnormal node occurs (S120; YES), the frame is discarded from the abnormal node (S145), and then the process proceeds to S160. Only will be described.

  In S160, a schedule switching process is executed. The schedule switching process is a process of transmitting a header for transmitting a response only to the slave 3 other than the abnormal node, that is, only to the normal slave 3.

Specifically, the schedule switching process, from the schedule table ST _0, deleting the header to the responding node to the slave 3 identified as an abnormal node generates a new schedule table.

As an example in Figure 12, when the slave 3b is identified as a failed node, indicating a new schedule table ST _1. In the new schedule table ST ₁ , the frame C 1 is deleted from the schedule table ST ₀ , a header (fourth) with the master 2 as a response node is transmitted, and after a further 500 ms has passed, a header with the slave 3 c as a response node ( 5th) is set to be transmitted. The schedule table ST ₁ is set to transmit a header (first) having the master 2 as a response node after another 1000 ms has elapsed.

That is, in the present embodiment, when the failed node is generated, and deletes the header to the responding node to the identified slave 3b as an abnormal node generates a new schedule table ST _1. Accordingly, since the new schedule table ST ₁ is set, the regular transmission processing (S130), the header to the responding node slave 3b identified as an abnormal node is being sent.

[2-2-2. Processing executed by the slave]
Next, slave regular processing executed by the slave 3 (control unit 31) in the present embodiment will be described with reference to the flowchart of FIG. In the following description, the slave 3a will be described as an example when a more specific example needs to be described.

In S405, a frame break detection process is executed. In the frame interruption detection process, the master 2 set not to transmit a header requesting a response to the slave 3 that is an abnormal node based on the new schedule table ST ₁ is transmitted to the slaves 3 other than the slave 3 that is the abnormal node. In this process, the received header is received as discard information, and an abnormal node is identified based on the header.

  That is, the frame interruption detection process detects that the reception of a frame that should be received periodically has been interrupted. In the frame interruption detection process, when there is a frame in which reception has been interrupted, a communication interruption detection flag is set, and information indicating a communication interruption frame, which is a frame in which reception has been interrupted, is recorded in the RAM 313.

  In subsequent S410, it is determined whether there is a frame in which reception is interrupted. Specifically, when the communication interruption detection flag is set, it is determined that there is a frame in which reception has been interrupted. If there is a frame in which reception has been interrupted, the process proceeds to S415, and if not, the process proceeds to S430.

In S415, where there is a frame in which reception has been interrupted, an abnormal node is identified. Specifically, the slave 3a, if the header of the frame received is disrupted is 0x05, based on the correspondence management table KT _1, it identifies the slave 3b as an abnormal node. Then, the abnormality flag of the slave 3b is set (see FIG. 10).

Next, in S420, similarly to S420 shown in FIG. 9, a setting is made to discard a frame that uses the abnormal node identified in S415 as a response node.
In subsequent S425, the communication interruption detection flag is reset, and the slave periodic processing is terminated.

It should be noted that the same processing as in FIG. 9 is executed after S430 when there is a frame in which reception is interrupted.
Next, the frame interruption detection process executed in S405 of the slave periodic process will be described with reference to the flowchart of FIG. The frame interruption detection process is a process for detecting whether or not there has been a frame reception interruption for each of the periodic frames set in the correspondence management table of the slave 3. Specifically, for example, in the case of a slave 3a, based on the correspondence management table KT _1, the return for each of the frames A1, B1, B2, C1, D1, after performing the frame interruption detection process, the process to slave periodic processing Let

  In S510, it is determined whether the frame is normally received. When both the header and the response are normally received, it is determined that the frame is normally received. If the frame is normally received, the process proceeds to S530. If the frame is not normally received, the process proceeds to S515.

  In S515, which is shifted when it is determined in S510 that the frame has not been normally received, it is determined whether or not the frame communication interruption timer is stopped. Hereinafter, the frame A1 will be described as an example of the frame.

  If the communication interruption timer of frame A1 is stopped, the process proceeds to S525, and if it is in operation, the process proceeds to S520. The communication interruption timer is a process executed by the control unit 31 as a process different from the frame interruption detection process, and is a process of measuring a communication interruption time that is a time from when the frame A1 is received until it is received next. is there.

  In S520, where it is determined that the communication interruption timer for the frame A1 is operating in S515 and the process proceeds to S520, the processing of the communication interruption timer for the frame A1 is continued. Then, the process proceeds to S535.

In S525, where it is determined that the communication interruption timer of the frame A1 is stopped in S515, the process of the communication interruption timer is started. Then, the process proceeds to S535.
In S530, where it is determined that the frame has been normally received in S510, and the communication interruption timer of the frame A1 is stopped, the communication interruption time is initialized, that is, the measured value is set to zero. Then, the process proceeds to S535.

In S535, it is determined whether or not the frame A1 is a frame in which reception is interrupted. Specifically, when the communication interruption time is equal to or greater than a communication interruption threshold which is a predetermined determination period, it is determined that the frame A1 is a frame in which reception is interrupted. Communication interruption threshold, for example, so on ten to several tens of times the period for one cycle of the schedule table ST _0, is set to a sufficiently longer time than the period in which the frame A1 is received. However, the communication interruption threshold may be set to an arbitrary value according to the communication system 1.

If it is determined that the received frame is interrupted, the process proceeds to S540. If it is not determined that the received frame is interrupted, the present frame interrupt detection process is terminated.
In S540, the frame A1 is recorded in the RAM 313 as a communication interruption frame.

In S545, a communication interruption detection flag is set. Then, the frame interruption detection process is terminated.
After the frame break detection process for the frame A1 is completed in this way, as described above, the frame break detection process is similarly performed for each of the frames B1, B2, C1, and D1, and then the slave periodic process is performed. Return processing to.

  The operation of the slave 3 configured as described above will be described. As an example, the slave 3a operates as follows when the header 0x05 is not received within the determination period indicated by the communication interruption threshold.

  That is, when the header 0x05 is not received within the determination period indicated by the communication interruption threshold, that is, when the frame C1 is not received, the slave 3a identifies the slave 3b as an abnormal node (S415). Then, after specifying the slave 3b as an abnormal node, the slave 3a operates so as not to receive the event frame transmitted by the slave 3b which is the abnormal node, that is, to discard it (S435).

[2-3. effect]
According to the second embodiment described in detail above, the following effects are obtained in addition to the effects [1A] and [1C] to [1E] of the first embodiment described above.

  [2A] The slave 3 is configured to recognize the slave 3 to which the master 2 does not transmit a header as an abnormal node. Based on the schedule table, the master 2 transmits, as discard information, a header that is a transmission command for transmitting a response only to the slaves 3 other than the abnormal node (S160).

  According to this, since an abnormal node can be identified without using the error notification frame in the first embodiment, the header assigned to the error notification frame can be used for other control and the like.

  [2B] The master 2 is configured not to transmit a header to the abnormal node. The slave 3 receives the header transmitted from the master 2 configured as described above to the slave 3 other than the abnormal node as discard information (S405). Based on the header transmitted as described above as the discard information, the slave 3 identifies the slave 3 whose header has not been transmitted from the master 2 within the determination period, which is the period represented by the communication interruption threshold, as an abnormal note. (S415). Then, the slave 3 is set to discard the event data that is the transmission source of the slave 3 specified as the abnormal node.

According to this, the same effect as the above [2A] is obtained.
In the second embodiment, S160 corresponds to an example of processing of the discard information transmitting unit, S405 (S510) corresponds to an example of processing of the discard information receiving unit, and S415 is an example of abnormal device specifying unit. It corresponds to.

[3. Other Embodiments]
As mentioned above, although embodiment of this invention was described, it cannot be overemphasized that this invention can take a various form, without being limited to the said embodiment.

  [3A] In the above embodiment, the slave 3 is configured to transmit an event frame when an event occurs. Specifically, when an event occurs, the slave 3 is configured to transmit an event frame when the bus 5 enters an idle state in which no frame is output on the bus 5. May be. Alternatively, the slave 3 may be configured to transmit an event frame when information permitting transmission of the event frame is output from the master 2 to the bus 5.

[3B] Although the frame configuration used in the communication system 1 is shown in FIG. 2 as an example, the frame configuration is not limited to this, and may be set as appropriate according to the communication system 1.
[3C] The communication system 1 may be a communication system that operates according to a master-slave method, a CSMA / CA method, a CXPI (Clock Extension Peripheral Interface) method that is a method in which these are combined, or the like.

  [3D] The functions of one constituent element in the above embodiment may be distributed as a plurality of constituent elements, or the functions of a plurality of constituent elements may be integrated into one constituent element. Moreover, you may abbreviate | omit a part of structure of the said embodiment. In addition, at least a part of the configuration of the above embodiment may be added to or replaced with the configuration of the other embodiment. In addition, all the aspects included in the technical idea specified only by the wording described in the claim are embodiment of this invention.

  [3E] The present invention relates to the communication system 1, the master 2, the slave 3, the control unit 21, the control unit 31, the program for causing the control unit 21 or the control unit 31 to function, the medium on which the program is recorded, the communication It can be realized in various forms such as a method.

  DESCRIPTION OF SYMBOLS 1 ... Communication system 2 ... Master 3 ... Slave 21 ... Control part 31 ... Control part 211 ... CPU 311 ... CPU.

Claims (5)

A master communication device (2) connected to be able to communicate with a plurality of slave communication devices (3) via a bus (5),
A transmission condition that is set in advance even when the master communication device transmits data in response to a transmission command that represents a command in which a device to which data is to be transmitted is specified, and there is no transmission command from the master communication device Specific information acquisition means (S110) for acquiring specific information that can specify which slave communication device out of the plurality of slave communication devices is abnormal, with the communication device that transmits data when is established as a slave communication device. , S115),
Discard information transmission means for transmitting, to at least slave communication devices other than the abnormal device, discard information for causing the abnormal device representing the slave communication device in which the abnormality has occurred to discard data that is a transmission source based on the specific information S150, S160),
With
The specific information acquisition means (S110) acquires, as the specific information, wakeup pulse transmission information that is information indicating whether or not the slave communication device has transmitted a wakeup pulse. A master communication device (2) connected to be able to communicate with a plurality of slave communication devices (3) via a bus (5),
A transmission condition that is set in advance even when the master communication device transmits data in response to a transmission command that represents a command in which a device to which data is to be transmitted is specified, and there is no transmission command from the master communication device Specific information acquisition means (S110) for acquiring specific information that can specify which slave communication device out of the plurality of slave communication devices is abnormal, with the communication device that transmits data when is established as a slave communication device. , S115),
Discard information transmission means for transmitting, to at least slave communication devices other than the abnormal device, discard information for causing the abnormal device representing the slave communication device in which the abnormality has occurred to discard data that is a transmission source based on the specific information S150, S160),
With
The specific information acquisition unit (S115) acquires sleep permission / prohibition information, which is information indicating whether sleep of the slave communication device is permitted or prohibited, as the specific information. The master communication device according to claim 1 or 2,
The discard information transmitting means (S150) transmits the discard information including identification information for identifying the abnormal device specified by the specific information. The master communication device according to claim 1 or 2,
The discard information transmitting means (S160) provides, as the discard information, the abnormal information for the slave communication device having a function of recognizing that the slave communication device to which the transmission command is not transmitted from the master communication device is the abnormal device. A master communication device comprising: transmitting a transmission command for transmitting data only to a slave communication device other than the device. A communication system including a master communication device and a plurality of slave communication devices, wherein the master communication device transmits a transmission command in which a device to which data is to be transmitted is specified, and the slave communication device transmits data according to the transmission command. And the slave communication device transmits data when a preset transmission condition is satisfied even when there is no transmission command from the master communication device. The slave communication device used in a communication system that does not transmit the transmission command to an abnormal device representing a slave communication device in which an abnormality has occurred among slave communication devices,
Discard information receiving means for receiving, from the master communication device, discard information for discarding data from which the abnormal device is a transmission source, wherein the master communication device has transmitted to the slave communication device other than the abnormal device Discard information receiving means (S400, S405) for receiving a transmission command as the discard information;
An abnormal device specifying means (S415) for specifying, as the abnormal device, a slave communication device that has not transmitted the transmission command by the master communication device within a determination period that is a predetermined period based on the discard information; ,
Based on the discard information, a data discarding unit (S420) for setting the slave communication device identified as the abnormal device by the abnormal device identifying unit to discard the data to be transmitted;
A slave communication device comprising:

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