JP2011228932A - Network system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a network system capable of increasing a reliability by determining validity of transmission data without shortening of data length that can be sent at one time even when the max length of a packet is predetermined.SOLUTION: An engine control device 102 creates a first packet 115 by first packet creation means 113, and a second packet 116 that includes data to determine validity of the first packet 115 by second packet creation means 114. The created first packet 115 is sent to a first transmission path 100 and the second packet 116 is sent to a second transmission path 101, respectively. The validity of the first packet 115 is determined using data to determine the validity of the second packet 116 by reception packet determination means 123 in an AT control device 103 that receives these packets.

Description

  The present invention relates to a network system that increases the reliability of data transmission performed between a plurality of control devices that are connected to a network and control different objects.

Conventionally, the following network systems are generally known as network systems that are generally well-known in the field of industrial equipment and the like and improve the reliability of transmitted and received data. In this network system, the station A and the station B are connected by a transmission path, and means for improving data reliability is used for data to be transmitted and received.
The transmitting station collects the data to be transmitted (hereinafter referred to as transmission data) and the data (CRC, sequence number, transmission destination, transmission source information, etc.) for determining the validity derived from the data in one transmission packet. To send. When the length of the transmission packet exceeds the packet length that can be transmitted at once, the transmission packet is divided into a plurality of packets so as to be within the packet length that can be transmitted.
The receiving station verifies the received transmission data with the data for judging the validity after receiving one packet if the transmission packet is not divided and after receiving all the packets if it is divided. Then, the validity is judged by judging whether there is an error or the like.

  In this technology, when a transmitted packet has its value changed due to noise or the like on the transmission path, the station on the packet receiving side detects the change based on data for judging validity, and transmits the packet. Can be discarded. By doing so, the reliability of the network system can be increased.

In addition to this technology, the following network system is known. Stations A and B of this network system are connected by two transmission lines, and means for increasing the reliability of transmitted and received packets is used.
The transmitting station collects the transmission data, and when the transmission data has a length that does not fit in one transmission packet, divides the transmission data into sub-packets that are less than the length that fits in one packet and less than a predetermined number, and A correction packet including correction data, which is data for determining validity, is generated using subpackets from the beginning to the end. Then, the subpacket and the correction packet are transmitted in order on the two transmission paths. When the transmission data has a length that can be accommodated in one frame, the same data is also transmitted without generating a correction packet.
If there is no delay or loss of subpackets, the receiving station receives the same packet from each transmission line at the same time, receives all subpackets and correction packets, determines the validity of the subpackets, and changes or loses them. If it is determined that the transmission data is valid, the transmission data is extracted (see, for example, Patent Document 1).

  In this technology, if there is a loss / change of a subpacket transmitted on only one transmission path, the receiving station uses the subpacket from the other transmission path and is transmitted on both transmission paths. If a subpacket is lost or changed, after receiving the correction packet, it can be determined that the subpacket is lost or changed, and the data can be restored using the data for determining the validity. it can. By doing so, the reliability of the network system can be increased.

Japanese Patent No. 4024988 (pages 6 to 14, FIG. 1)

However, the above-described conventional technology has the following problems.
When transmitting transmission data and data for determining the validity derived therefrom in a single transmission packet, in a network system in which the maximum packet length is determined in advance, the data length that can be transmitted at once There is a problem that becomes short.
In the case of transmitting by dividing into a plurality of transmission packets, a means for dividing into a plurality of packets is required on the transmitting side, and a means for returning the plurality of packets to the receiving side is required. Even when the transmission is divided by this means, there is a problem that the reception side cannot judge the validity of the received transmission data until all the transmission packets arrive.

Next, in the method of Patent Document 1, when the transmission data does not fit in one packet, it is possible to determine the validity of the received transmission data until all the subpackets and correction packets including the transmission data are received. There is a problem that can not be.
On the other hand, even when the transmission data fits in one packet, there is a problem that the validity of the transmission data cannot be determined until the same transmission packet that arrives after receiving one transmission packet is received.

  The present invention has been made in order to solve the above-described problems. Even when the maximum packet length is determined in advance, the transmission data can be validated without shortening the data length that can be transmitted at one time. The first object is to obtain a network system capable of improving the reliability by judging the characteristics.

  In addition, it is a second object of the present invention to obtain a network system that can improve the reliability by determining the validity of transmission data without dividing and transmitting a packet even when the maximum length of the packet is predetermined. Objective.

  In addition, after receiving a transmission packet, determine the validity by using the data for judging the validity received from another transmission line without waiting for the data reception for judging the validity that arrives from the same transmission line. A third object is to obtain a network system that can improve reliability.

  The network system according to the present invention is a network system in which a plurality of nodes having a communication function are connected by first and second transmission paths and transmit / receive a packet, wherein the node transmits a packet (hereinafter referred to as a transmission node). Is a first packet creation means for creating a first packet composed of one or more data, and for determining the validity of the first packet created by the first packet creation means Second packet creating means for creating a second packet including data, first transmitting means for sending the first packet created by the first packet creating means on the first transmission path, second packet A node (2) that includes a second transmitting means for transmitting the second packet created by the creating means onto the second transmission path; (Hereinafter referred to as a receiving node) is a first receiving means for receiving a first packet from the first transmission line, a second receiving means for receiving a second packet from the second transmission line, and a second receiving means. And a received packet determining means for determining the validity of the first packet received by the first receiving means, using data for determining the validity included in the second packet received by the means. Is.

As described above, according to the present invention, when transmission / reception is performed between nodes connected to the first and second transmission paths, the transmission node determines the validity of the first packet and the first packet. A second packet including data for transmission to the first transmission path and the second transmission path, respectively, and the receiving node receives the first packet from the first transmission path and the second transmission path, respectively. The second packet is received, and the validity of the first packet is determined using data for determining the validity included in the second packet.
As described above, since the data for determining the validity is not included in the first packet, in order to determine the validity included in the second packet without shortening the data length included in the first packet. The validity of the first packet can be determined using the data.
Further, since the first packet and the second packet are transmitted through different transmission paths, the second packet is used without waiting for the reception of the second packet as in the case of transmission through the same transmission path. The validity of the first packet can be determined.

It is a block block diagram which shows the network system concerning Embodiment 1 of this invention. It is a figure which shows the process of the network system concerning Embodiment 1 of this invention, and the flow of the packet on a transmission line. It is a figure which shows the error which generate | occur | produced in the 1st packet of the network system concerning Embodiment 1 of this invention. It is a block block diagram which shows the network system concerning Embodiment 2 of this invention. It is a figure which shows the process of the network system concerning Embodiment 2 of this invention, and the flow of the packet on a transmission line. It is a block block diagram which shows the network system concerning Embodiment 3 of this invention. It is a figure which shows the structure of the time segment in the FlexRay communication concerning Embodiment 3 of this invention. It is a figure which shows the flow of the packet on the process of a network system concerning Embodiment 3 of this invention, and a transmission line.

Hereinafter, preferred embodiments of the network system of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts will be described with the same reference numerals.
In the following embodiment, a case where this network system is mounted on a vehicle will be described.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a network system according to Embodiment 1 of the present invention.
In FIG. 1, a first transmission path 100 and a second transmission path 101 are each a CAN (Controller Area Network) that is a protocol adopting a CSMA / CA (Carrier Sense Multiple Access / Collection Aidance) method as a network connection method. ) A CAN network that performs communication (hereinafter referred to as “CAN communication”) in accordance with (International Standard ISO11898) is used. Here, the unit of data transmitted and received at one time is referred to as a packet. In CAN communication, the maximum length of a packet that can be transmitted at one time is determined to be 8 bytes. If this exceeds this, a Transport protocol for separately dividing the packet is used. Will be used. Since the Transport protocol is rarely used in normal communication, it is not used in this embodiment.
Note that the network is not limited to the above, and any network that uses the CSMA / CA method or a protocol that employs a similar method as the network connection method and has a maximum packet length that can be transmitted at one time. For example, another network may be used.

  An engine control device 102, an AT (Automatic Transmission) control device 103, a steering control device 104, and a meter control device 105 are connected to the first transmission path 100 and the second transmission path 101, respectively.

The engine control apparatus 102 (transmission node) includes a CPU 1 (111) and a communication controller 1 (112). The CPU 1 (111) collects transmission data and creates a first packet 115, and first packet creation means 113, and validity for judging the validity of the transmission data included in the first packet 115. Second packet creating means 116 for creating a second packet 116 including determination data is included.
Data for detecting whether or not unintentional errors (due to the influence of noise etc. on the transmission path) are included in the transmission data, data for correcting detected errors, Data for indicating the transmission destination and transmission source, data for indicating the transmission order of packets, and the like are included, but the effect of the present invention does not affect the type of data for validity determination, so here the transmission data is not affected. The data is used to detect whether an error is included.
On the other hand, as data for detecting an error, data such as a cyclic redundancy check code (CRC) and a parity bit is generally used, but is not limited thereto.

The CPU 1 (111) delivers the first packet 115 and the second packet 116 to the communication controller 1 (112). The communication controller 1 (112) is a part having a communication function, and a first transmission unit 117 that transmits a packet to the first transmission path 100 and a second transmission that transmits a packet to the second transmission path 101. Means 118 are provided.
Here, the CPU 1 (111) and the communication controller 1 (112) are displayed as separate ones, but the function of the communication controller may be incorporated in the CPU 1. In addition, there are other necessary components for CAN communication, but since they are not directly related to the network system described in the present embodiment, description thereof is omitted.

  The AT control device 103 (receiving node) is a device that performs communication, and includes the CPU 2 (121) and the communication controller 2 (122), and receives the first packet 115 and the second packet 116. The CPU 2 (121) determines the validity by detecting the error of the transmission data contained in the paired first packet 115 using the validity judgment data contained in the second packet 116. If there is no error, the reception packet determination means 123 is provided for extracting data from the first packet 115. Error detection by the received packet determining means 123 is performed by calculating correctness determination data from the received first packet 115 and comparing it with correctness determination data extracted from the second packet 116. If the comparison results are different, it is determined that an error is included. If no error is included, the transmission data included in the first packet 115 is extracted as it is.

The communication controller 2 (122) is a part having a communication function, and a first receiving means 127 that receives data from the first transmission path 100 and a second reception that receives data from the second transmission path 101. Means 128 are provided.
Here, the CPU 2 (121) and the communication controller 2 (122) are displayed as separate ones, but the CPU 2 (121) can also incorporate the function of the communication controller.
The CAN communication of the AT control apparatus 103 includes other necessary components, but the description is omitted because it is not directly related to the function of the network system described in the present embodiment.

  Further, in this configuration, the communication controller 1 (112) has only the transmission means, and the communication controller 2 (122) has only the reception means, but this is to facilitate explanation of the functions of the present invention. This is because the configuration is specialized for transmission or reception. Actually, this is not the case, and the communication controller is provided with both means for transmission and reception. Although the communication controller is described separately from the CPU, the effect of the present embodiment is not affected even when the CPU and the communication controller are integrated.

  A steering control device 104 and a meter control device 105 are connected to the first transmission path 100 and the second transmission path 101, respectively. The steering control device 104 and the meter control device 105 are connected to the engine control device 102 and the AT control device 103 via the first transmission path 100 and the second transmission path 101, respectively, but will be described in the present embodiment. The description is omitted because it is not directly related to the network system.

FIG. 2 is a diagram showing processing of the network system and the flow of packets on the transmission line according to the first embodiment of the present invention.
In FIG. 2, the engine control device processing 201 is processing content related to communication of the engine control device 102. The AT control device process 202 is a processing content related to the communication of the AT control device 103. The packet 203 in the first transmission path is a packet in the first transmission path 100. The packet 204 in the second transmission path is a packet in the second transmission path 101. Each is shown along a time chart.

FIG. 3 is a diagram showing an error that has occurred in the first packet of the network system according to the first embodiment of the present invention.
In FIG. 3, the correct and incorrect first packets are shown.

Next, the operation of the network system according to the first embodiment of the present invention will be described with reference to FIG.
Since this embodiment does not use a time-synchronized network connection method, the processing time of the engine control device 102 and the processing time of the AT control device 103 are not synchronized.

First, each process from the process 11 to the process 14 by the engine control apparatus 102 will be described.
In the process 11, the first packet creation unit 113 collects transmission data and creates a first packet 115.
In the process 12, the second packet creating unit 114 calculates data for confirming reliability from the first packet 115, and creates a second packet 116 including this data.
In process 13, the first transmission unit 117 transmits the first packet 115 on the first transmission line 100.
In process 14, the second transmission means 118 transmits the second packet 116 on the second transmission path 101.

Next, each process from the process 21 to the process 23 by the AT control apparatus 103 will be described.
In process 21, the first receiving unit 127 receives the first packet 115 from the first transmission line 100.
In process 22, the second receiving unit 128 receives the second packet 116 from the second transmission path 101.
In the process 23, the received packet judging means 123 judges the correctness by detecting the error of the paired first packet 115 using the data for confirming the reliability included in the second packet 116. To do. Specifically, the received packet determining unit 123 calculates correctness determination data from the received first packet 115 and compares it with correctness determination data extracted from the second packet 116. If the comparison results are different, an error is included and it is determined that the comparison is not valid. If no error is included and it is valid, the transmission data included in the first packet 115 is extracted as it is.

  In the timing chart shown in FIG. 2, only the processing related to transmission / reception is shown in order to clarify the characteristic part of the first embodiment. However, actually, this is not the case, and there are processes unique to the engine control device 102 and the AT control device 103, respectively. These processes are not shown in the time chart, but are executed at times when this process is not executed.

  Next, an operation in the case where the first packet 115 has no error such as bit inversion due to noise or the like on the first transmission path 100 and is valid will be described with reference to the timing chart of FIG.

First, at time t11, the first packet creation unit 113 executes the process 11 to create the first packet 11 (215).
Subsequently, at time t12, the second packet creation unit 114 executes the process 12 to obtain the second packet 11 (216) that forms a pair including the validity determination data of the first packet 11 (215). create.
Next, at time t <b> 13, the first transmission unit 117 executes the process 13 and transmits the first packet 11 (215) on the first transmission path 100.
Subsequently, at time t14, the second transmission unit 118 executes the process 14, and the second packet 11 paired with the first packet 11 (215) transmitted on the second transmission path 101 at time t13. (216) is transmitted.

Next, at time t <b> 21, the first receiving unit 127 executes the process 21 and receives the first packet 11 (215) from the first transmission line 100.
Subsequently, at time t <b> 22, the second receiving unit 128 executes the process 22 and receives the second packet 11 (216) from the second transmission path 101.
Subsequently, at time t23, the received packet determination unit 123 executes the process 23, and the validity determination data calculated from the first packet 11 (215) and the validity included in the second packet 11 (216). The judgment data are compared to determine whether any errors are included. In this case, since no error is included, it is determined that the first packet 11 (215) is valid, and the included transmission data is extracted.

Next, the operation of the network system when the first transmission packet contains an error and is not valid will be described with reference to the timing chart of FIG.
Note that the processing of the engine control apparatus 102 from time t11 to time t14 is the same as the above-described operation when the transmitted packet is normal, and thus description thereof is omitted.
Here, the 1-bit value of the first packet 11 (215) transmitted in the process 13 is inverted as shown in FIG. 3 due to the influence of noise or the like on the first transmission path 100 (from the front). 4th bit is changed from 0 to 1).

Subsequently, since the processing of the AT control apparatus 103 from time t21 to time t22 is the same as described above, the description thereof is omitted.
Next, at time t23, the received packet determination unit 123 executes the process 23, and uses the validity determination data included in the second packet 11 (216) to make a pair of the first packet 11 (215). ) To determine the validity of the packet. In this case, the comparison result between the validity determination data calculated from the first packet 11 (215) and the validity determination data extracted from the second packet 11 (216) is different by the received packet determination unit 123. Therefore, it can be determined that the first packet 11 (215) is not valid, and the included transmission data is not extracted.

  As described above, by using the validity determination data of the first packet 11 (215) included in the first packet 11 (215) and the second packet 11 (216), the first packet is valid. It is possible to determine whether the network system is valid or not, and the reliability of the network system can be improved.

  Here, the first packet 11 (215) and the second packet 11 (216) have been described, but the engine control device 102 and the AT control device 103 perform similar processing for other packets to be transmitted. By determining whether there is an error for all packets, it is possible to determine whether the packet is valid or not, and improve the reliability of the network system.

  Further, here, the case where an error is included in the first packet 11 (215) has been described, but in the case where an error is included in the second packet 11 (216) or an error is included in both packets. However, by determining whether there is an error in the same way, it is possible to determine whether it is valid or not, and the reliability of the network system can be improved.

  That is, in a network in which the maximum length of packets that can be transmitted at a time is determined, the second packet 116 including the validity determination data of the first packet 115 is transferred to the second transmission line different from the first transmission line 100. By transmitting at 101, the validity can be improved without reducing the data length that can be transmitted by the first packet as compared to the case of transmitting the transmission data and the data for judging the validity as one packet by one transmission path. By determining, the reliability of the network system can be improved.

  Further, in a network system in which the maximum length of packets that can be transmitted at one time is determined, the second packet 116 including the validity determination data of the first packet 115 is transmitted as a second transmission different from the first transmission path 100. By transmitting on the path 101, without reducing the transmission data length on one transmission path, compared to the case of transmitting the transmission data and the validity determination data together, without dividing and transmitting the packet, By determining the validity, the reliability of the network system can be improved.

  Furthermore, in a network in which the maximum length of packets that can be transmitted at one time is determined, the second packet 116 including the data for determining the validity of the first packet 115 is transmitted in a second transmission different from the first transmission path 100. By transmitting at almost the same time on the path 101, it is possible to shorten the time until the reception of the validity determination data compared to the case of transmitting the packet including the validity determination data after the transmission of the packet including the transmission data. At the same time, the reliability of the network system can be improved by determining the legitimacy.

As described above, according to the first embodiment, in the first control device and the second control device connected by the first transmission path and the second transmission path, the first control apparatus that transmits a packet is: First packet creating means for creating a first packet composed of one or more data, and second packet creating means for creating a second packet including data for determining validity of the first packet; , First transmission means for transmitting the first packet on the first transmission path, and second transmission means for transmitting the second packet on the second transmission path.
The second control device that receives the packet includes a first receiving unit that receives the first packet from the first transmission path, and a second reception that receives the second packet from the second transmission path. And received packet determining means for determining the validity of the paired first packet using the data of the validity determining data included in the second packet.
For this reason, the first control device can reduce the amount of data that can be originally transmitted in one packet and can transmit the packet without storing the validity determination data in the first packet. In the second control device, the first control device Using the validity determination data calculated from the first packet received from the first transmission path and the validity determination data contained in the second packet received almost simultaneously from the second transmission path, By determining the legitimacy, a network system that improves reliability can be obtained.

  Further, in the first embodiment, if the second packet paired after receiving the first packet cannot be received for a certain period of time, the reliability is further improved by discarding the first packet. Can be made.

Embodiment 2. FIG.
4 is a block diagram showing a network system according to Embodiment 2 of the present invention.
In FIG. 4, reference numerals 100 to 105, 111 to 118, 121 to 123, 127, and 128 are the same as those in FIG. In FIG. 4, the CPU 1 (111) of the engine control apparatus 102 includes transmission data importance determination means 401 (transmission packet importance determination means). The transmission data importance determination unit 401 determines the importance of the transmission data included in the first packet 115. If the transmission data importance determination unit 401 determines that the transmission data importance is high, the transmission data importance determination unit 401 sends the validity determination data to the second packet creation unit 114. The second packet creation instruction including is issued.

  In the configuration of FIG. 4 as well, the communication controller 1 (112) has only transmission means, and the communication controller 2 (122) has only reception means, but this makes it easy to explain the function of the present invention. This is because the configuration is specialized for transmission or reception. Actually, this is not the case, and the communication controller is provided with both means for transmission and reception. Although the communication controller is described separately from the CPU, the effect of the present embodiment is not affected even when the CPU and the communication controller are integrated.

FIG. 5 is a diagram showing processing of the network system according to the second embodiment of the present invention and the flow of packets on the transmission path.
In FIG. 5, reference numerals 201 to 204 are the same as those in FIG. Note that the processing with the same number as in FIG. 2 is the same processing as in FIG.

Next, the operation of the network system according to the second embodiment of the present invention will be described with reference to FIG.
In process 31, when the transmission data importance determination means 401 of the engine control apparatus 102 determines the importance of transmission data included in the first packet 115 and determines that the importance is high, the second packet If the second packet creation instruction including the validity determination data is issued to the creation means 114 and it is determined that the importance is not high, the second packet creation means 114 is not instructed, so the second packet The processing related to 116 is not performed.
In the process 32, the received packet judging means 123 judges the legitimacy by detecting the error of the paired first packet 115 using the legitimacy judging data included in the second packet. Specifically, the received packet determining unit 123 calculates correctness determination data from the received first packet 115 and compares it with correctness determination data extracted from the second packet 116. If the comparison results are different, an error is included and it is determined that the comparison is not valid. If no error is included and it is valid, the transmission data included in the first packet 115 is extracted as it is.
At this time, if the second packet 116 as a pair has not been received for a certain period of time, the transmission data included in the first packet 115 is extracted without performing validity determination.

  In the timing chart shown in FIG. 5, only the processing related to transmission / reception is shown in order to clarify the characteristic part of the second embodiment. However, actually, this is not the case, and there are processes specific to the engine control device 102 and the AT control device 103, respectively. These processes are not shown in the time chart, but are executed at times when this process is not executed.

Next, the operation when there is no error such as bit inversion due to noise in the first packet 115 on the first transmission line 100 and it is valid will be described with reference to the timing chart of FIG. .
Here, the processing when the importance of transmission data is high will be described with reference to time t31 to time t35 of the engine control device processing 201 and time t41 to time t43 of the AT control device processing 202.

First, at time t31, the first packet creation unit 113 executes the process 11 to create the first packet 21 (315).
Subsequently, at time t32, the transmission data importance determination unit 401 executes the process 31. Here, since it is determined that the transmission data included in the first packet 21 (315) is highly important, the second packet generation unit 114 is instructed to generate a second transmission packet.
Next, at time t33, in response to an instruction from the transmission data importance determination unit 401, the second packet creation unit 114 executes the process 12 and forms a pair including the validity determination data of the first packet. 2 packet 21 (316) is created.
Subsequently, at time t <b> 34, the first transmission unit 117 executes the process 13 and transmits the first packet 21 (315) on the first transmission path 100.
Next, at time t <b> 35, the second transmission unit 118 executes the process 14, and transmits the second packet 21 (316) on the second transmission path 101.

Next, at time t <b> 41, the first receiving unit 127 executes the process 21 and receives the first packet 21 (315) from the first transmission path 100.
Subsequently, at time t <b> 42, the second receiving unit 128 executes the process 22 and receives the second packet 21 (316) from the second transmission path 101.
Next, at time t43, the received packet determining unit 123 executes the process 32, and the validity determination data calculated from the first packet 21 (315) and the validity included in the second packet 21 (316). The determination data is compared, and it is determined whether or not an error is included in the first packet. In this case, since no error is included, it is determined that the first packet 21 (315) is valid, and the included transmission data is extracted.

Next, processing when the importance of transmission data is not determined to be high will be described with reference to time t36 to time t38 of the engine control device processing 201 and time t44 to time t45 of the AT control device processing 202.
First, at time t36, the first packet creation unit 113 executes the process 11 and creates the first packet 22 (317).
Subsequently, at time t37, the transmission data importance determination unit 401 executes the process 31. Here, since it is not determined that the transmission data included in the first packet 22 (317) is highly important, the second packet generation unit 114 is not instructed to generate the second transmission packet.
Next, at time t <b> 38, the first transmission unit 117 executes the process 13 and transmits the first packet 22 (317) on the first transmission line 100.

Next, at time t <b> 44, the first receiving unit 127 executes the process 21 and receives the first packet 22 (317) from the first transmission path 100.
Subsequently, at time t45, the received packet determination unit 123 executes the process 32 and receives only the first packet 22 (317). Therefore, the error detection is not performed, and the first packet is changed to the first packet. Extract included transmission data.

Since the operation of the network system when it is not valid because the first packet 21 (315) contains an error is the same as the operation of the network system when it is not valid shown in the first embodiment, the description thereof is omitted. .
Here, if the first packet 22 (317) contains an error and is not valid, it cannot be detected by the network system according to the second embodiment, but the first packet 22 (317) contains the error. Since it is not judged that the included transmission data is highly important, the influence on the network system is small.

  Thus, the first packet 21 (315) included in the first packet 21 (315) and the second packet 21 (316) including the transmission data determined to be highly important by the engine control apparatus 102. By using the validity determination data, it is possible to determine whether the first packet determined to be highly important on the transmission side is valid or not, and improve the reliability of the network system. .

  Here, the first packet 21 (315) and the second packet 21 (316) have been described, but the engine control device 102 and the AT control device 103 perform the same processing for other packets to be transmitted. By judging whether there is an error in all packets judged to be highly important on the sending side, it is possible to judge whether it is valid or not, and improve the reliability of the network system Can do.

  In addition, here, we would like to explain the case where the first packet contains an error. However, if the second packet contains an error or if both packets contain an error, the error is detected in the same way. By determining whether or not there is, it can be determined whether it is valid or not, and the reliability of the network system can be improved.

  That is, in a network in which the maximum length of packets that can be transmitted at one time is determined, the second packet 116 including the validity determination data of the first packet 115 including the transmission data determined to be highly important on the transmission side. Is transmitted on the second transmission line 101 different from the first transmission line 100, the transmission data and the validity judgment data are transmitted as one packet on one transmission line. The reliability of the network system can be improved by determining the legitimacy of all the packets that are determined to be highly important on the transmission side without reducing the data length that can be transmitted with this packet.

  Further, in a network in which the maximum length of packets that can be transmitted at one time is determined, the second packet 116 including the validity determination data of the first packet 115 including the transmission data that is determined to be highly important by the transmission side. Compared to the case where transmission data and validity determination data are transmitted together without reducing the transmission data length in one transmission path by transmitting on the second transmission path 101 different from the first transmission path 100. Thus, it is possible to improve the reliability of the network system by determining the legitimacy of all packets determined to be highly important on the transmission side without dividing and transmitting the packets.

  Furthermore, in a network in which the maximum length of packets that can be transmitted at a time is determined, the second packet including the validity determination data of the first packet 115 including the transmission data determined to be highly important on the transmission side. 116 is transmitted almost simultaneously on the second transmission line 101 different from the first transmission line 100, so that it is more legitimate than the case where the packet including the validity determination data is transmitted after the transmission of the packet including the transmission data. The time until the reception of the sex determination data can be shortened, and the reliability of the network system can be improved by determining the legitimacy.

As described above, in the second embodiment, in the first control device and the second control device connected by the first transmission path and the second transmission path, the first control apparatus that transmits a packet is: First packet creation means for creating a first packet composed of one or more data, transmission packet importance judgment means for judging the importance of the first packet, and reliability of the first packet Second packet creation means for creating a second packet including data for confirmation, first transmission means for sending the first packet on the first transmission path, and second packet for the second Second transmission means for transmitting on the transmission path is provided.
The second control device that receives the packet includes a first receiving unit that receives the first packet from the first transmission path, and a second reception that receives the second packet from the second transmission path. And a received packet judging means for judging the legitimacy of the paired first packet using data for confirming the reliability included in the second packet.
Therefore, in the first control device, in the first packet including data that is determined to be important, the amount of data that can be originally transmitted in one packet is reduced, and the validity determination data is not included in the first packet. In the second control device, the validity judgment data calculated from the first packet received from the first transmission path and the legitimacy included in the second packet received almost simultaneously from the second transmission path By using the sex determination data to determine the validity of the first packet, a network system that improves the reliability can be obtained.

Embodiment 3 FIG.
FIG. 6 is a block diagram showing a network system according to Embodiment 3 of the present invention.
In FIG. 6, reference numerals 100 to 105, 111 to 118, 121 to 123, 127, and 128 are the same as those in FIG. In the third embodiment, the first transmission path 100 and the second transmission path 101 in FIG. 6 are connected to a FlexRay (registered trademark) communication protocol Ver2. 1 rev. A transmission path that performs communication (hereinafter referred to as FlexRay communication) compliant with A (reference www.flexray.com). Details of the FlexRay communication will be described later.

  The time synchronization unit 602 synchronizes the time with respect to the network system between the nodes in order to perform FlexRay communication. This is necessary for all nodes that perform FlexRay communication, such as the engine control device 102, the AT control device 103, the steering control device 104, and the meter control device 105.

  Next, the CPU 2 (122) of the AT control apparatus 103 is provided with received data importance determining means 601 (received packet importance determining means). The reception data importance determination means 601 determines the importance of the transmission data included in the first packet 115, and if the reception data importance determination means 601 determines that the importance is high, the reception data determination means 123 includes the second packet 116. An instruction is issued to determine the validity by detecting an error in the transmission data included in the paired first packet 115 using the validity determination data.

  In the configuration of the third embodiment, the communication controller 1 (112) has only the transmission means and the communication controller 2 (122) has only the reception means. This explains the function of the present invention. This is because the configuration is specialized for transmission or reception for the sake of simplicity. Actually, this is not the case, and the communication controller is provided with both means for transmission and reception. Although the communication controller is described separately from the CPU, the effect of the third embodiment is not affected even when the CPU and the communication controller are integrated.

  Here, the time division multiplexing communication network connection method according to the FlexRay communication used in the third embodiment will be described. In addition, since FlexRay communication is a known technique, description is abbreviate | omitted regarding the detail which is not related to invention.

FIG. 7 is a diagram showing the structure of time segments in the FlexRay communication according to Embodiment 3 of the present invention.
In FIG. 7, time segments 701 and 702 are the m-th cycle and m + 1-th cycle time segments, respectively. Each of the time segments 701 and 702 includes a static segment 703, a dynamic segment 704, a symbol window 705, and a network idle time (hereinafter referred to as NIT) 706. By repeating these for each time segment, message transmission / reception is performed. Do.

  The static segment 703 is composed of time slots 707 having the same length, and is set as a time slot for transmitting / receiving each node in advance. That is, there is a maximum length that can be transmitted through each network system in advance for the data length that can be transmitted by each node. The dynamic segment 704 can transmit and receive variable-length data at an arbitrary timing. Since the symbol window 705 and NIT 706 are not related to message transmission / reception, description thereof is omitted.

  In the communication node, if one communication controller transmits / receives to / from two communication paths, the static segment 703, the time slot 707, the dynamic segment 704, the symbol window 705, and the NIT 706 included in the same are common. And the start time must be synchronized.

  On the other hand, since the dynamic segment 704 and the symbol window 705 can be selected not to be used as FlexRay communication, they are not used in the network system described in the third embodiment.

  In the third embodiment, FlexRay communication is used as the network connection method. However, the present invention is not limited to this, and a network system that uses a time-division multiplex communication method or a protocol similar to this is used as the network connection method. Other protocols may be used as long as the network is synchronized in time and has a maximum packet length that can be transmitted at one time.

FIG. 8 is a diagram showing the processing of the network system and the flow of packets on the transmission line according to the third embodiment of the present invention.
8, 201 to 204 are the same as those in FIG. 2, and 703 and 707 are the same as those in FIG. Note that the processing with the same number as in FIG. 2 is the same processing as in FIG. In FIG. 8, a network system time 800 is shown.

  Next, the operation of the network system according to the third embodiment of the present invention will be described with reference to FIG.

First, each process from the process 41 to the process 43 by the engine control apparatus 102 will be described.
In the process 41, the time synchronization means 602 performs time synchronization between nodes connected to the network system. This process is performed after the engine control device 102 is activated or when the synchronization with the network system is lost, and is not performed on a regular basis.
In process 42, the first transmission unit 117 performs a procedure for transmitting the first packet 115 on the first transmission line 100.
In processing 43, the second transmission means 118 performs a procedure for transmitting the second packet 116 on the second transmission path 101.
In this network system, packets are not sent on the transmission line immediately after execution of processing 42 and processing 43, but since a time slot that can be transmitted in advance is determined, the packet is sent on the transmission path after waiting for it. Will be. In the third embodiment, transmission of first packet 115 and second packet 116 is set in a time slot transmitted at the same timing.

Next, each process from the process 51 to the process 55 by the AT control apparatus 103 will be described.
In process 51, the time synchronization means 602 performs time synchronization between nodes connected to the network system. This process is performed after the AT control apparatus 103 is activated or when the synchronization with the network system is lost, and is not performed regularly.
In process 52, the first receiving means 127 receives the first packet 115 from a predetermined time slot on the first transmission line 100.
In process 53, the second receiving means 128 receives the second packet 116 from a predetermined time slot on the second transmission path 101.
In process 54, the received data importance determination means 601 determines the importance of the transmission data included in the first packet 115. If the received data importance determination means 601 determines that the importance is high, the received data importance determination means 123 sends a second An instruction is issued to determine the validity by detecting the error detection of the first packet 115 using the validity determination data included in the packet 116. If it is determined that the importance is not high, the received packet determination unit 123 is instructed not to perform the validity determination.

  In the process 55, the received packet determining unit 123 uses the validity determination data included in the second packet 116 according to the instruction of the received data importance determining unit 601, and an error is detected in the first packet 115 that is a pair. Judgment of legitimacy is performed by detecting whether it is not included. Specifically, the received packet determining unit 123 calculates correctness determination data from the received first packet 115 and compares it with correctness determination data extracted from the second packet 116. If the comparison results are different, it is determined that an error is included. If no error is included, it is determined to be valid, and the transmission data included in the first packet 115 is extracted. When the validity determination is not performed, the transmission data included in the first packet 115 is extracted as it is.

  In the timing chart shown in FIG. 8, only the processing related to transmission / reception is shown in order to clarify the characteristic part of the third embodiment. However, this is not the case in practice, and the engine control device 102 and the AT control device 103 each have unique processing. These processes are not shown in the time chart, but are executed at times when this process is not executed.

  Next, the operation when there is no error such as bit inversion caused by noise in the first packet on the first transmission path 100 and it is valid will be described with reference to the timing chart of FIG. Here, the network system time 800 is a time synchronized with the network system.

First, a process that the engine control apparatus 102 and the AT control apparatus 103 perform at the time of activation will be described.
At time t51, the time synchronization unit 602 executes the process 41 and performs time synchronization with the network system. Thereafter, the engine control apparatus 102 can transmit.
Subsequently, at time t61, the time synchronization unit 602 executes the process 51 to perform time synchronization with the network system. Thereafter, the AT control apparatus 103 can receive.

Next, processing when it is determined that the transmission data included in the first packet 115 is highly important will be described from time t71 to time t79 of the network system time 800.
First, at time t71, the first packet creation unit 113 executes the process 11 to create the first packet 31 (815).
Subsequently, at time t72, the second packet creation unit 114 executes the process 12 to obtain the second packet 31 (816) that forms a pair including the validity determination data of the first packet 31 (815). create.
Next, at time t <b> 73, the first transmission unit 117 executes the process 42, and performs a procedure for transmitting the first packet 31 (815) on the first transmission path 100.
Subsequently, at time t <b> 74, the second transmission unit 118 executes the process 43 and performs a procedure for transmitting the second packet 31 (816) on the second transmission path 101.
Next, at time t75, in a predetermined time slot, the first packet 31 (815) and the second packet 31 (816) are transmitted to the first transmission line 100 and the second transmission line 101, respectively. It will be transmitted at the same time.

Next, at time t76, the first receiving unit 127 executes the process 52, and receives the first packet 31 (815) from a predetermined time slot on the first transmission path 100.
Subsequently, at time t77, the second receiving unit 128 executes the process 53, and receives the second packet 31 (816) from a predetermined time slot of the second transmission path 101.
Next, at time t78, the received data importance determination means 601 determines the importance of the transmission data included in the packet 31 (815). Here, since it is determined that the importance is high, the reception packet determination unit 123 is instructed to perform the determination of validity.
Subsequently, at time t79, the received packet determining unit 123 executes the process 55, and according to the determination of the received data importance determining unit 601, the validity determination data calculated from the first packet 31 (815) and the second The validity determination is performed by comparing the data for determining the validity included in the packet 31 (816) and determining whether or not an error is included. In this case, since no error is included, it is determined to be valid, and the transmission data included in the first packet 31 (815) is extracted.

Next, processing when it is determined that the importance of transmission data is not high will be described from time t81 to time t89 of the network system time 800.
Here, the processes from time t81 to time t84 are the same as the processes from time t71 to time t74, and the processes from time t86 to time t87 are the same as the processes from time t76 to time t77. Description is omitted.
The packet to be used is the first packet 32 (817) for the first packet, the second packet 32 (818) for the second packet, and the first transmission line 100 and the second packet at time t85, respectively. The transmission lines 101 are simultaneously transmitted.

At time t88, the received data importance determination means 601 determines the importance of the transmission data included in the first packet 32 (817). Here, since it is not determined that the importance is high, the received packet determination unit 123 is instructed not to perform the determination of validity.
Subsequently, at time t89, the received packet determining unit 123 executes the process 55, and according to the determination of the received data importance determining unit 601, the first packet 32 (815) is not subjected to the validity determination. Extract included transmission data.

Next, since the operation of the network system when an error is included in the first packet 31 (815) is the same as the operation of the network system when it is not valid shown in the first embodiment, the description thereof is omitted. .
If the first packet 32 (817) is not valid because it contains an error, the network system in the third embodiment cannot detect it, but it is included in the first packet 32 (817). Since the importance of the transmission data is not judged to be high, the influence on the network system is small.

  As described above, the first packet 31 (815) included in the first packet 31 (815) and the second packet 31 (816) including the transmission data determined to be highly important by the AT control apparatus 103. By using the validity determination data, it is possible to determine whether the first packet determined to be highly important on the reception side is valid or not, and improve the reliability of the network system. .

  Here, the first packet 31 (815) and the second packet 31 (816) have been described. However, the engine control device 102 and the AT control device 103 perform similar processing for other packets to be transmitted. By judging whether there is an error for all packets judged to be highly important on the receiving side, it is possible to judge whether it is valid or not, and improve the reliability of the network system Can do.

  Also, here, we would like to explain the case where an error is included in the first packet. However, when the error is included in the second packet or when both packets include an error, the same method can be used. It can be detected and the reliability of the network system can be improved.

  That is, in a network in which the maximum length of packets that can be transmitted at a time is determined, the second packet 116 including the validity determination data of the first packet 115 is transferred to the second transmission line different from the first transmission line 100. 101, and whether or not to determine the validity on the receiving side is compared with the case where the transmission data and the validity determination data are transmitted as one packet on one transmission path. It is possible to improve the reliability of the network system by determining the legitimacy of all packets determined to be highly important on the receiving side without reducing the data length that can be transmitted in one packet.

  Further, in a network in which the maximum length of packets that can be transmitted at one time is determined, a second packet 116 that includes data for determining validity of the first packet 115 is different from the first transmission channel 100. The transmission data and the validity determination data are transmitted together without reducing the transmission data length on one transmission path by determining whether or not to perform the validity determination on the receiving side. Compared to the above, it is possible to improve the reliability of the network system by judging the validity of all packets judged to be highly important on the receiving side without dividing and transmitting the packets. .

  Furthermore, in a network in which the maximum length of packets that can be transmitted at one time is determined, the second packet 116 including the data for determining the validity of the first packet 115 is transmitted in a second transmission different from the first transmission path 100. Compared with the case where the packet including the validity determination data is transmitted after the transmission of the packet including the transmission data by determining whether or not the determination of the validity is performed on the receiving side at the same time on the receiving side. The time until the reception of the sex determination data can be shortened, and the reliability of the network system is improved by determining the legitimacy of all packets determined to be highly important on the receiving side. be able to.

As described above, the first control device that transmits a packet in the first control device and the second control device connected by the first transmission path and the second transmission path is the third embodiment. First packet creation means for creating a first packet composed of one or more data, and second packet creation for creating a second packet including data of validity determination data of the first packet Means, first transmission means for transmitting the first packet on the first transmission path, and second transmission means for transmitting the second packet on the second transmission path.
The second control device that receives the packet includes a first receiving unit that receives the first packet from the first transmission path, and a second reception that receives the second packet from the second transmission path. Means for determining the importance of the first packet, and the validity of the first packet to be paired is determined using the data of the validity determination data included in the second packet. Receiving packet judging means.
For this reason, the first control device can reduce the amount of data that can be originally transmitted in one packet and can transmit the packet without storing the validity determination data in the first packet. In the second control device, the first control device In the first packet including the data judged to be important received from the transmission path, the validity judgment data to be calculated and the validity judgment data contained in the second packet received simultaneously from the second transmission path are included. By using it, it is possible to determine the validity of the first packet, thereby obtaining a network system that improves the reliability.

  In the third embodiment, if the second packet cannot be received in a predetermined time slot, the reliability of the network system can be further improved by discarding the first packet.

  Furthermore, in the first to third embodiments, it has been described that the second packet includes data for determining validity, such as detecting an error. However, the transmission destination as supplementary information of the first packet is described. Or the data for indicating the transmission source, the reliability determination data such as the transmission order of the packet is included in the second packet, the transmission destination is not different, the data is not received from the unintended transmission source, the packet By determining the validity based on whether the arrival order is not changed or whether the packet is lost, the reliability of the network system can be improved.

  In addition, for the supplementary information included in these second packets, data for detecting errors and correcting detected errors are included in the second packets, thereby further improving the reliability of the network system. be able to.

  In the first to third embodiments, the case where there are two control devices is described as an example. However, the present invention is not limited to this, and even when three or more control devices are used, Similar effects can be obtained.

DESCRIPTION OF SYMBOLS 100 1st transmission path 101 2nd transmission path 102 Engine control apparatus 103 AT control apparatus 104 Steering control apparatus 105 Meter control apparatus 111 CPU1
112 Communication controller 1
113 1st packet creation means 114 2nd packet creation means 115 1st packet 116 2nd packet 117 1st transmission means 118 2nd transmission means 121 CPU2
122 Communication controller 2
123 received packet judging means 127 first receiving means 128 second receiving means 201 engine control device processing 202 AT control device processing 203 packet on the first transmission path 204 packet on the second transmission path 215 first packet 11
216 Second packet 11
315 First packet 21
316 Second packet 21
317 First packet 22
401 Transmission data importance judgment means 601 Reception data importance judgment means 602 Time synchronization means 701 Cycle m Time segment 702 Cycle m + 1 Time segment 703 Static segment 704 Dynamic segment 705 Symbol window 706 NIT (network idle time)
707 Time slot 800 Network system time 815 First packet 31
816 Second packet 31
817 First packet 32
818 second packet 32

Claims (8)

A network system in which a plurality of nodes having a communication function are connected by first and second transmission paths and transmit and receive packets,
A node that transmits the packet (hereinafter referred to as a transmission node)
First packet creation means for creating a first packet composed of one or more data;
Second packet creating means for creating a second packet including data for judging the validity of the first packet created by the first packet creating means;
First transmission means for transmitting the first packet created by the first packet creation means on the first transmission path;
Second transmission means for transmitting the second packet created by the second packet creation means onto the second transmission path;
A node that receives the packet (hereinafter referred to as a receiving node)
First receiving means for receiving the first packet from the first transmission path;
Second receiving means for receiving the second packet from the second transmission path;
Using the data for determining the validity included in the second packet received by the second receiving means, the validity of the first packet received by the first receiving means is determined. A network system comprising: a received packet judging means for performing   The transmission node generates the second packet corresponding to each of the first packets to be transmitted by the second packet generation unit, and the first packet is transmitted on the first transmission path. 2. The network system according to claim 1, wherein the second packet corresponding to the second transmission path is transmitted when the second packet is transmitted. The sending node
Transmission packet importance determination means for determining the importance of the first packet created by the first packet creation means,
2. The network according to claim 1, wherein the second packet creation means creates the second packet for the first packet determined to be important by the transmission packet importance judgment means. system. The receiving node is
When the first packet is received by the first receiving means, the received packet determining means uses data for determining the validity included in the second packet corresponding to the first packet. The network system according to claim 2, wherein validity of the first packet is determined. The receiving node is
Receiving packet importance determining means for determining the importance of the first packet received by the first receiving means;
3. The network system according to claim 2, wherein the received packet determining unit determines the validity of the first packet only when it is determined to be important by the received packet importance determining unit. The receiving node is
When the second packet is received by the second receiving unit, the received packet determining unit uses the data for determining the legitimacy included in the second packet. 4. The network system according to claim 2, wherein validity of the corresponding first packet is determined. The received packet determining means includes
In determining the validity of the first packet, if the second packet corresponding to the first packet is not received, it is determined that the first packet is not valid. The network system according to claim 4 or 5. Each node connected to the first and second transmission lines is
It has time synchronization means to synchronize the time between nodes,
The transmission node transmits the first packet on the first transmission path and the second packet corresponding to the first packet on the second transmission path at a predetermined first time. Send at the same time,
The receiving node receives the first packet from the first transmission path and the second packet corresponding to the first packet from the second transmission path at a predetermined second time. The network system according to claim 1, wherein the network system receives simultaneously.

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