JP4333585B2 - Vehicular data relay system, vehicular data relay device, and vehicular data transmission node - Google Patents

Description

  The present invention relates to a vehicular data relay system in which a vehicular data relay device relays data received from a vehicular data transmission node via a network, a vehicular data relay device and a vehicle used in the vehicular data relay system It relates to a data transmission node.

For example, Patent Document 1 discloses a configuration in which a data relay device relays data received from a data transmission node via a network.
JP 2000-207324 A

  By the way, as one of this type of data relay device, there is a guarantee type data relay device that limits the amount of data (traffic) received by the data relay device according to the capability of the data relay device. In the relay device, the reception process for storing the data received from the data transmission node in the temporary buffer is executed by interruption, and the main process for storing the data stored in the temporary buffer in the main buffer is executed at a predetermined cycle. Is common. Therefore, in a guarantee type data relay apparatus, as shown in FIG. 5, a time difference (shift) between the reception process execution timing and the main process execution timing generally occurs as a relay delay time.

  However, in a configuration in which a guarantee type data relay device is mounted on a vehicle as a vehicle data relay device, for example, for switch operation data (for example, temperature setting data of an air conditioner) according to a user's switch operation or vehicle travel control. The relay delay time when relaying the corresponding travel control data (for example, vehicle speed data) is desirably as short as possible in consideration of operability and safety.

  The present invention has been made in view of the above circumstances, and an object thereof is to shorten a relay delay time which is a time difference between the execution timing of the reception process and the execution timing of the main process in the vehicular data relay apparatus. An object is to provide a vehicular data relay system, a vehicular data relay device, and a vehicular data transmission node.

  According to the vehicular data relay system described in claim 1, the vehicular data transmission node transmits data to the vehicular data relay device via the network, and the vehicular data relay device is transmitted from the vehicular data transmission node. When the data is received via the network, the received data is stored in the temporary buffer by executing the receiving process by interruption, and the main process is executed at a predetermined cycle, so that the data is stored in the temporary buffer. It is determined whether the data is stored. If data is stored in the temporary buffer, the data stored in the temporary buffer is stored in the main buffer. In this case, the vehicular data relay device transmits a timing signal synchronized with the execution timing of the main process to the vehicular data transmission node, and the vehicular data transmission node receives the timing signal from the vehicular data relay device. The data is transmitted to the vehicle data relay device in synchronization with the timing at which the timing signal is received.

  Thus, in the vehicle data relay device, the timing signal is transmitted to the vehicle data transmission node in synchronization with the execution timing of the main process, so that the data from the vehicle data transmission node is synchronized with the execution timing of the main process. Since the data is received, the reception process for storing the data received from the vehicle data transmission node in the temporary buffer and the main process for storing the data stored in the temporary buffer in the main buffer are executed in synchronization. It is possible to reduce the relay delay time, which is the time difference between the execution timing of the reception process and the execution timing of the main process. Accordingly, for example, when relaying switch operation data, operability can be improved by promptly relaying the switch operation data, and when traveling control data is relayed, for example, Safety can be improved by relaying the control data promptly.

  According to the vehicular data relay system described in claim 2, the vehicular data relay device and the vehicular data transmission node transmit and receive timing signals via a network different from the network that transmits and receives data. As a result, it is possible to avoid an increase in traffic corresponding to the timing signal in the network for transmitting and receiving data, and it is not necessary to transmit and receive the timing signal as frame format data, and it is sufficient to transmit and receive as a simple on / off signal. The delay due to transmission / reception of the timing signal can be suppressed as much as possible.

  According to the vehicular data relay device according to claim 3, when data is received from the vehicular data transmission node via the network, the received data is temporarily received by executing the reception process by interruption. And determining whether data is stored in the temporary buffer by executing the main processing at a predetermined cycle. If the data is stored in the temporary buffer, the data stored in the temporary buffer is stored. Is stored in the main buffer, and in this case, a timing signal synchronized with the execution timing of the main process is transmitted to the vehicle data transmission node. As a result, the relay delay time, which is the time difference between the execution timing of the reception process and the execution timing of the main process, can be shortened by being used together with the vehicle data transmission node described in claim 1.

  According to the data transmission node of the fourth aspect, data is transmitted to the vehicle data relay device via the network. In this case, when the timing signal is received from the vehicle data relay device, the timing signal is received. The data is transmitted to the vehicular data relay device in synchronization with the received timing. As a result, when used together with the vehicle data relay device described in claim 1, the vehicle data relay device reduces the relay delay time, which is the time difference between the execution timing of the reception process and the execution timing of the main process. Can be made.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 4. FIG. 1 shows the overall configuration of a vehicle data relay system mounted on a vehicle. The vehicular data relay system 1 includes a vehicular data transmission node 2, a vehicular data relay device 3, and a vehicular data reception node 4. The vehicular data transmission node 2 and the vehicular data relay device 3 transmit data to a network 5. The vehicle data relay device 3 and the vehicle data reception node 4 are configured to transmit and receive data via the network 6.

  In this case, the networks 5 and 6 correspond to an information system in-vehicle LAN or a body system in-vehicle LAN. For example, if the network 5 is an information system in-vehicle LAN and the network 6 is a body system in-vehicle LAN, the information Data is relayed from the vehicle-mounted in-vehicle LAN to the body-based in-vehicle LAN by the vehicle data relay device 3, while the network 5 is a body-based in-vehicle LAN and the network 6 is an information-based in-vehicle LAN. If there is, the data is relayed by the vehicle data relay device 3 from the body-based in-vehicle LAN to the information-based in-vehicle LAN. The networks 5 and 6 may be configured by wire, may be configured by wireless, or may be configured by mixing wired and wireless. good.

  The vehicular data relay device 3 includes a temporary buffer 3a and a main buffer 3b. When data is received from the vehicular data transmission node 2 via the network 5, the reception process is executed by interruption. Thus, the received data is stored in the temporary buffer 3a, and the main process is executed at a predetermined cycle (for example, a cycle of 10 milliseconds) to determine whether the data is stored in the temporary buffer 3a. When data is stored in the temporary buffer 3a, the data stored in the temporary buffer 3a is stored in the main buffer 3b.

  Here, in the present embodiment, the vehicle data relay device 3 and the data transmission node 2 are also connected via a transmission line 7 different from the network 5, and are synchronized with the execution timing of the main processing (time (Synchronized) timing signal is transmitted to the vehicle data transmission node 2 via the transmission line 7.

  Next, the operation of the above configuration will be described with reference to FIGS. FIG. 2 is a flowchart showing the process executed by the vehicular data relay device 3 and the process executed by the vehicular data transmission node 2, and FIG. 3 shows a time chart.

  First, the vehicular data relay device 3 transmits a timing signal to the vehicular data transmission node 2 via the transmission line 7 when an event having a predetermined cycle occurs as a main process (step S1).

  When the timing signal is received from the vehicular data relay device 3 via the transmission line 7, the vehicular data transmission node 2 determines whether there is data waiting for transmission at that time (step S11). If there is data waiting for transmission at that time (“YES” in step S11), the data waiting for transmission is transmitted to the vehicle data relay device 3 via the network 5 (step S12).

  The vehicular data relay device 3 monitors whether data is received from the vehicular data transmission node 2 via the network 5, and the data is received from the vehicular data transmission node 2 via the network 5. Then, by executing the reception process by interruption, the received data is stored in the temporary buffer 3a (step S2). Then, the vehicular data relay device 3 determines whether data is stored in the temporary buffer 3a after a predetermined time has elapsed since the transmission of the timing signal to the vehicular data transmission node 2 as the main processing. (Step S3) When data is stored in the temporary buffer 3a (“YES” in Step S3), the data stored in the temporary buffer 3a is stored in the main buffer 3b (Step S4).

  Through the series of processes described above, in the vehicle data relay device 3, as shown in FIG. 4, it is possible to suppress the time difference (shift) between the execution timing of the reception process and the execution timing of the main process as much as possible. It becomes possible to shorten the relay delay time. A predetermined time (determination waiting time) from when the timing signal is transmitted to the vehicle data transmission node 2 to when it is determined whether or not data is stored in the temporary buffer 3a is required for transmission / reception of the timing signal. It is determined based on the transmission delay time and the transmission delay time required for data transmission / reception.

  As described above, according to the present embodiment, in the vehicular data relay device 3, the timing signal is transmitted to the vehicular data transmission node 2 in synchronization with the execution timing of the main process, thereby the vehicular data transmission node. 2 is received in synchronization with the execution timing of the main process, so that the data received from the vehicle data transmission node 2 is stored in the temporary buffer 3a and the data stored in the temporary buffer 3a. Can be executed in synchronization with the main process stored in the main buffer 3b, and the relay delay time, which is the time difference between the execution timing of the reception process and the execution timing of the main process, can be shortened.

  In this case, the vehicle data relay device 3 and the vehicle data transmission node 2 are configured to transmit and receive the timing signal via the transmission line 7 which is a network different from the network 5 that transmits and receives data. In the network 5 for transmitting and receiving signals, it is possible to avoid an increase in traffic corresponding to the timing signal, and it is not necessary to transmit and receive the timing signal as frame format data. Delay due to transmission / reception of can be suppressed as much as possible.

The present invention is not limited to the above-described embodiment, and can be modified or expanded as follows.
If the network that transmits and receives data can tolerate sufficient traffic, it may be configured to transmit and receive timing signals via a network that transmits and receives data, rather than through a network that is different from the network that transmits and receives data. good.

Functional block diagram showing an embodiment of the present invention flowchart Time chart The figure which shows schematically the execution timing of a reception process, and the execution timing of a main process The figure which shows schematically the execution timing of the reception process in the conventional structure, and the execution timing of the main process

Explanation of symbols

In the drawings, 1 is a vehicle data relay system, 2 is a vehicle data transmission node, 3 is a vehicle data relay device, 3a is a temporary buffer, 3b is a main buffer, and 5 is a network.

Claims (4)

A vehicle data transmission node that transmits data to the vehicle data relay device via a network; and
The reception processing for storing the data received from the vehicle data transmission node via the network in the temporary buffer is executed by interruption, and it is determined whether the data is stored in the temporary buffer and the data is stored in the temporary buffer. A vehicular data relay system comprising a vehicular data relay device that executes main processing for storing data stored in the temporary buffer in a main buffer when the data is stored in a predetermined cycle,
The vehicle data relay device transmits a timing signal synchronized with an execution timing of a main process to the vehicle data transmission node,
The vehicular data transmission node transmits data to the vehicular data relay device in synchronization with a timing at which a timing signal is received from the vehicular data relay device. In the vehicle data relay system according to claim 1,
The vehicular data relay device and the vehicular data transmission node transmit and receive timing signals via a network different from a network that transmits and receives data. Used in a vehicular data relay system together with a vehicular data transmission node that transmits data to a vehicular data relay device via a network, and stores data received from the vehicular data transmission node via the network in a temporary buffer The reception process is executed by interruption, and it is determined whether or not data is stored in the temporary buffer. When data is stored in the temporary buffer, the data stored in the temporary buffer is stored in the main buffer. A vehicular data relay device that executes main processing to be stored at a predetermined cycle,
A vehicular data relay apparatus, wherein a timing signal synchronized with execution timing of a main process is transmitted to the vehicular data transmission node. The reception processing for storing the data received from the vehicle data transmission node via the network in the temporary buffer is executed by interruption, and it is determined whether the data is stored in the temporary buffer and the data is stored in the temporary buffer. When stored, it is used in a vehicle data relay system together with a vehicle data relay device that executes main processing for storing data stored in the temporary buffer in a main buffer at a predetermined cycle, and the data is transmitted via a network. Vehicle data transmission node for transmitting to the vehicle data relay device,
A vehicle data transmission node, wherein data is transmitted to the vehicle data relay device in synchronization with a timing at which a timing signal is received from the vehicle data relay device.

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