JP2008311978A - Transit connection unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow changing of specifications of state transition of the network management function of a transit connection unit. <P>SOLUTION: The on-vehicle transit connection unit 10 forms a network 32 while being interposed between busses 31 connecting electronic control units 30 each and relays a message transmitted and received between the electronic control units 30 belonging to a different bus 31. The transit connection unit 10 comprises: a network management processing circuit 11 for executing the network management function of the transit connection unit 10; and a storage circuit having a state transition table T where the transition destination of the state transition condition of the network management function is changed into parameters. The network management processing circuit 11 monitors the state transition using the state transition table T. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a relay connection unit, and more particularly, enables specification change of a network management function of the relay connection unit.

  Conventionally, an electronic control unit (ECU) for controlling equipment mounted on a vehicle is connected to multiple communication buses via a relay connection unit (gateway) to construct a network, and transmission / reception between ECUs belonging to different buses An in-vehicle communication system that relays messages to be relayed by the relay connection unit is employed.

  In such an in-vehicle communication system, each ECU and the relay connection unit may have a network management function. The network management function means that the ECU connected to the bus and the relay connection unit send and receive ring messages to each other to initialize the ECU, start the network, set the network, detect and process the ECU and network operating status, and send signals. This is a function that performs processing such as reading and setting of parameters of the ECU and the like, and the network management function ensures the safety and reliability of communication between the ECU and the relay connection unit.

One of these network management functions is state transition processing. As shown in Non-Patent Document 1, the relay connection unit and the ECU are in an initial state where initialization is performed after power-on, a reset state which is a state immediately before transition to another state, and a normal state which is a high power consumption state State (normal operation state), sleep state that is a low power consumption state, sleep state that is normal but can enter sleep state, and is in any state set by the network management function. The transition process is a process of transitioning the state of the relay connection unit or ECU from one state to another state when a predetermined condition is satisfied.
The relay connection unit and the ECU are provided with a network management processing circuit for executing a network management function, and the network management processing circuit holds conditions for state transition and information on the transition destination.

  On the other hand, in recent years, with the increase in functionality and performance of vehicles, the number of devices mounted on the vehicle has increased, and the number of messages transmitted and received by the relay connection unit has increased rapidly. For this reason, relay processing performed by the relay connection unit and processing for the network management function are also increasing, and it is desired that the relay connection unit perform each processing at high speed.

Therefore, Japanese Patent Laying-Open No. 2006-352235 (Patent Document 2) proposes a method in which the relay processing of the relay connection unit is configured by hardware without using software processing of the CPU. As a relay process, the relay connection unit performs a destination search process for specifying a message relay destination and a switching process for switching a fixed-length cell of a message. In Patent Document 1, the CPU performs a destination search process and a switching process. Instead, destination search processing and switching processing are performed in a hardware search engine and self-routing module.
By configuring and executing each process of the relay connection unit by hardware, the processing performance of the CPU does not affect the processing speed of the relay connection unit. In addition, although the CPU can perform only one process at the same time, it is possible to perform two or more processes in parallel in hardware, and each process of the relay connection unit can be performed at high speed.

However, since Patent Document 2 uses hardware, when changing specifications such as parameters used for processing, the hardware configuration must be changed, and it is difficult to easily change the specifications. There is a problem.
In particular, when the network management function is configured by hardware, the state transition condition and the transition destination used in the state transition processing are also configured in advance in hardware. However, since the conditions or transition destinations are different for each vehicle type, there is a problem in that the network management function must be configured by hardware for each vehicle type, and the networked management function implemented in hardware cannot be shared.

Network Management Concept and Application Programming Interface Published: July 26, 2004 Publisher: OSEK / VDX Internet (URL: http://portal.osek-vdx.org/files/pdf/specs/nm253.pdf) JP 2006-352235 A

  The present invention has been made in view of the above-described problem, and enables specification change of the state transition of the network management function of the relay connection unit, and also makes the hardware network management function common regardless of the vehicle type. Is an issue.

In order to solve the above-described problems, the present invention provides an in-vehicle device that forms a network by interposing electronic control units between buses connected to each other and relays messages transmitted and received between the electronic control units belonging to different buses. A relay connection unit,
A network management processing circuit for executing a network management function;
A storage circuit having a state transition table that parameterizes the transition destination of the state transition condition of the network management function,
The network management processing circuit provides an in-vehicle relay connection unit that monitors the state transition using the state transition table.

The network management processing circuit performs state transition processing of the network management function based on the state transition table stored in the storage circuit. The state transition table is stored in advance in a storage circuit provided separately from the network management processing circuit, and the network management processing circuit reads the state transition table from the storage circuit when the relay connection unit is connected to the power source.
As described above, since the state transition table is stored in the storage circuit, when the state transition condition and the transition destination of the relay connection unit are changed, it is only necessary to rewrite the state transition table of the storage circuit. Specification changes can be made.

  In addition, since the state transition conditions and transition destinations of relay connection units are parameterized and listed as a state transition table, developers can easily understand the state transition processing operations when developing relay connection units. The developer can easily change the state transition table and can easily verify the operation of the state transition process.

The network management processing circuit is preferably formed of an integrated circuit, and the storage circuit is preferably formed of a rewritable nonvolatile memory.
While the network management processing circuit is formed by hardware consisting of integrated circuits, the state transition table that is different for each vehicle type is read from the memory circuit, so the network management processing circuit must be hardware-based regardless of state transition processing. It is possible to share a hardware network management processing circuit regardless of the type of vehicle.
The integrated circuit (Integrated Circuit) forming the network management processing circuit may be an ASIC (Application Specific Integrated Circuit) that is an integrated circuit designed and manufactured for the network management function. Further, an FPGA (Field Programmable Gate Array) that is an integrated circuit whose internal circuit configuration can be changed may be used.
The ASIC or FPGA may include not only a network management processing function but also a processing function for the operation of the relay connection unit, such as a process for reading a parameter from a nonvolatile memory, a relay process, and a main loop process.

In addition, when the network management processing circuit is configured by CPU software, the CPU can perform only one process at a time. However, by configuring the network management processing circuit by hardware, two or more processes can be performed simultaneously. This makes it possible to increase the processing speed of the relay connection unit.
Furthermore, by using a rewritable nonvolatile memory as the storage circuit, parameters such as transition destinations can be rewritten according to specification changes.

The state transition table preferably includes a timer condition for the relay connection unit to transition to a standby state.
The state transition table includes an area for setting a standby state of the relay connection unit, a timer condition for transitioning to the standby state, timer control information that is a time for maintaining the standby state, and the like as spares. After setting the state transition table in the development of the relay connection unit, add a new timer condition specification to verify the operation of the network management function, and if it becomes necessary to transition the relay connection unit to the standby state, The timer conditions for the relay connection unit to transition to the standby state are described in the area provided as. Therefore, it is not necessary to set a new area for describing the timer condition in the state transition table, and the timer condition can be easily added.

As described above, according to the relay connection unit of the present invention, since the state transition table is stored in the storage circuit, when changing the state transition condition and transition destination of the relay connection unit, the state transition table of the storage circuit It is only necessary to rewrite, and the specification of the state transition table can be easily changed.
In addition, the network management processing circuit is formed by hardware consisting of the controller circuit, and the state transition table that is different for each vehicle type is read from the memory circuit, so the hardware network management processing circuit is shared regardless of the vehicle model. can do.

Embodiments of the present invention will be described with reference to the drawings.
1 to 4 show a first embodiment of the present invention.
The in-vehicle relay connection unit 10 of the present invention forms a network 32 by interposing electronic control units (ECUs) 30 between buses 31 connected to each other, and transmits and receives messages between the ECUs 30 belonging to different buses 31. Is relayed.
In this embodiment, the relay connection unit 10 is interposed between the two buses 31A and 31B to form the network 32, and the two ECUs 30-1 and 30-2 are connected to the two buses 31A and 31B, respectively. is doing. The communication protocol is CAN.

As shown in FIG. 1, the relay connection unit 10 includes a relay connection unit LSI 40, a power source 41, an EEPROM 12, a driver 42, and a connector 43 on the same substrate.
A relay connection unit LSI 40 (Large Scale Integrated Circuit) is an integrated circuit (IC), and is configured as hardware by an ASIC designed for the relay connection unit 10. The relay connection unit LSI 40 includes a network management processing circuit 11, an EEPROM processing circuit 13 that reads parameters of the EEPROM 12, a transmission / reception circuit 14, a relay processing circuit 15, and a parameter processing circuit 17.
The EEPROM 12 which is a rewritable nonvolatile memory is connected to the relay connection unit LSI 40 and stores a state transition table T in which the transition destination of the state transition condition of the network management function of the network management processing circuit 11 is parameterized. .
The power supply 41 is constituted by an LSI which is an integrated circuit, and is connected to the relay connection unit LSI 40 to supply power for driving the relay connection unit LSI 40.
The drivers 42A and 42B are also constituted by an LSI which is an integrated circuit, provided for each bus 31 and connected to each bus 31 via a connector 43. Further, the relay connection unit LSI 40 is connected, and in order to transmit or receive a message transmitted / received by the relay connection unit LSI 40 to or from the bus 31, the potential of the data signal constituting the message is adjusted.

In the relay connection unit LSI 40, the network management processing circuit 11 is connected to the relay processing circuit 15 and transmits / receives a network management message (NM message) to / from another ECU 30 via the relay processing circuit 15.
Further, the network management processing circuit 11 executes a network management function, and the network management function is such that each ECU 30 connected to the relay connection unit 10 and the relay connection unit 10 via the bus 31 outputs a ring message of an NM message. This is a function of performing state transition and monitoring processing of the relay connection unit using the state transition table T by transmitting and receiving in order.
In this embodiment, since the two buses 31 </ b> A and 31 </ b> B are connected to the relay connection unit 10, the network management processing circuit 11 transmits and receives a ring message for each bus 31.

  FIG. 2 is an example of a state transition diagram of the relay connection unit 10. In the present embodiment, the network management function of the network management processing circuit 11 is in any one of the states S1 to S7 in FIG. 2, and the relay connection unit 10 is controlled according to the states S1 to S7 of the network management function. Further, the network management function states S1 to S7 of the network management processing circuit 11 transition from the current state to another state according to predetermined conditions E1 to E9.

For example, when the power supply 41 is turned on, the relay connection unit 10 is in the off state S1. At this time, if the condition E1 is set to a condition in which the relay processing circuit 15 receives a state transition enable signal from another ECU 30 as a ring message and passes it to the network management processing circuit 11, the network management processing circuit 11 satisfies the condition E1. The network management function changes from the off state S1 to the initial state S2.
Similarly, when the network management function of the network management processing circuit 11 in the initial state S2 satisfies the condition that the predetermined time elapses (condition E2), the relay connection unit 10 transitions from the initial state S2 to the reset state S3.
In the reset state S3, when the condition that the network management function of the network management processing circuit 11 does not detect an error (condition E3) is satisfied, the relay connection unit 10 transitions to the normal state S5 and detects an error. When the condition (condition E4) is satisfied, the state transits to the limp home state S6.

  The network management processing circuit 11 having such a network management function reads a data signal indicating the state transition table T stored in the EEPROM 12 via the EEPROM processing circuit 13.

The EEPROM 12 which is a rewritable nonvolatile memory is connected to the EEPROM processing circuit 13 of the relay connection unit LSI 40 and stores a state transition table T in which the transition destination of the state transition condition of the network management function is parameterized. .
FIG. 3 shows a state transition table T. The state transition table T in FIG. 3A is a table showing the relationship between the state S and the transition condition E of the relay connection unit 10 in FIG.
In the present embodiment, the network management function of the network management processing circuit 11 is one of seven states S1 to S7 as shown in FIG. 2, and there are nine conditions E1 to E9 for transition to each state. Since it is necessary, the state transition table T describes seven states and nine conditions.
Further, in the region (the square) where the state S and the condition E in the state transition table T cross each other, the processing information P when the condition E is satisfied when the relay connection unit 10 is in the state S is described.
Further, the state transition table T reserves in advance an area that can be described by rewriting the EEPROM 12 although the state and conditions are not described. In the present embodiment, a spare area that can describe ten states S8 to S17 and ten conditions E9 to E19 is secured in advance. The spare area is used when there is a specification change such as adding a condition E or a state S to the state transition table T for a certain input.

FIG. 3B shows the format of the processing information P written in each square of the state transition table T. From the upper bit, the 12-bit timer control bit 41, the 4-bit transmission processing bit 42, the 1-bit An initialization bit 43 and a 5-bit transition destination bit 44 are provided.
In the timer control bit 41, a specific setting time of the timer condition is described for each condition E including a condition related to time. For example, when waiting for 1 second is described in the processing information P of the grid where the state S2 and the condition E2 cross, when an event E2 occurs in the state S2, by referring to the processing information P, Start the timer based on the timer control bit, wait for the next event input in the S2 state, and if the event is not input by 1 second, the next state described in the processing information P as the completion of the standby Transition to.

The transmission processing bit 42 is a bit for issuing a command to transmit a network management message (NM message) from the network management processing circuit 11 to another ECU 30. The NM message includes a wake-up message, an alive message, a ring message, a limp There are four types of messages: home messages. When transitioning to the state described in the transition destination bit 44, the network management processing circuit 11 transmits the message described in the transmission processing bit 42 to the other ECU 30 via the relay processing circuit 15.
For example, in the state transition table T, when a transmission instruction of a limp home message is described in the transmission processing bit 42 of the processing information P of the crossing cell of the condition E4 that the relay connection unit 10 has an error with the reset state S3 The network management processing circuit 11 transmits the limp home message to the other ECUs 30 at the same time that the relay connection unit 10 is shifted to the transition destination state S.

The initialization bit 43 initializes the network management processing circuit 11 and the transmission / reception circuit.
The transition destination bit 44 describes a transition destination when the condition E is satisfied when the relay connection unit 10 is in the state S.
For example, in the state transition table T, the relay connection unit 10 is in the reset state S3, and the transition destination bit 44 of the processing information P of the crossing square of the condition E4 that there is an error is the link that the relay connection unit 10 is in the error state When the home state S6 is described, the relay connection unit 10 transitions from the reset state S4 to the limp home state S6 if the condition E4 is satisfied.

  Note that the number of bits required to configure the state transition table T is obtained by (number of bits representing each process of transmission processing, timer control, and initialization + number of transition destination bits) × number of states × number of conditions. In this embodiment, (17 + 5) × 17 × 19 = 7106 bits.

  The EEPROM 12 also stores a communication speed parameter used by the transmission / reception circuit 14 and a routing table used by the relay processing circuit 15. The transmission / reception circuit 14 transmits the communication speed parameter via the parameter processing circuit 17 and the EEPROM processing circuit 13. While reading from the EEPROM 12, the relay processing circuit 15 reads the routing table from the EEPROM 12.

The main loop receiving circuit 16 is connected to the power supply 41 and is also connected to the network management processing circuit 11, the relay processing circuit 15, the parameter processing circuit 17, and the transmission / reception unit 14, and the power supply 41 is turned on to the relay connection unit 10. In this case, the main loop receiving circuit 16 outputs a wakeup signal to the network management processing circuit 11, the relay processing circuit 15, the parameter processing circuit 17, and the transmission / reception unit 14 to wake up each processing unit.
The relay processing circuit 15 is connected to the transmission / reception circuits 14A and 14B connected to the buses 31A and 31B, and relays relay messages transmitted from one ECU 30 to another ECU 30 belonging to a different network 31.
The transmission / reception circuits 14A and 14B are provided for each of the buses 31A and 31B, and transmit the NM message from the network management processing circuit 11 and the relay message from the relay processing circuit 15 to the bus 31.

Next, the operation of the relay connection unit 10 will be described.
First, an operation in which the network management processing circuit 11 reads the state transition table T from the EEPROM 12 when the power supply 41 is turned on to the relay connection unit 10 will be described.
When the power supply 41 is turned on to the main loop receiving circuit 16 of the relay connection unit 10, the main loop receiving circuit 16 wakes up.
The main loop receiving circuit 16 transmits a wakeup signal to the network management processing circuit 11, the parameter processing circuit 17, the transmission / reception circuits 14A and 14B, and the relay processing circuit 15, and each processing unit that receives the wakeup signal wakes up.
After the parameter processing circuit 17 wakes up and becomes operable, it issues a wakeup signal to the EEPROM processing circuit 13 to wake up the EEPROM processing circuit 13. The EEPROM processing circuit 13 reads the state transition table T from the EEPROM 12 and outputs the state transition table T to the network management processing circuit 11 via the parameter processing circuit 17.

Next, the operation of the state transition process of the network management processing circuit 11 using the state transition table T will be described. As an example, a case where the relay connection unit 10 transitions from the state S1 to the state S2 and from the state S2 to the state S3 will be described.
FIG. 4 is a specific example of the state transition table T of FIG. 3, and the processing information P1 shown in FIG. 4B is described in the crossing cells of the OFF state S1 and the condition E1 of FIG. . The condition E1 is a condition that the network management processing circuit 11 receives a state transition enable signal. The state transition enable signal is received from another ECU 30 as a ring message, or is received when the ignition key is turned on. The state transition enable signal is a signal for enabling the network management function to execute the state transition.
Further, processing information P2 shown in FIG. 4C is written in the cells where the OFF state S2 and the condition E2 cross each other. Condition E2 is a condition of waiting until a predetermined time elapses.

Next, the network management processing circuit 11 determines whether or not the condition E1 is satisfied in the off state S1.
When the network management processing circuit 11 receives a state transition enable signal from another ECU 30, the condition E1 is satisfied. At this time, the network management processing circuit 11 makes a transition to the initial state S2 described in the transition destination bit 44 with reference to FIG. 4B which is the processing information P1. At the same time, since a transmission instruction for the wake-up message is described in the transmission processing bit 42, the network management processing circuit 11 transmits the wake-up message to the other ECU 30. Since the timer control bit 41 is not described (zero is described), the network management processing circuit 11 changes the state of the relay connection unit 10 without waiting time and wakes up when receiving the state transition enable signal. Send a message.

When the relay connection unit 10 is in the initial state S2, the network management processing circuit 11 satisfies the condition E2 of waiting for a predetermined time. Therefore, the network management processing circuit 11 refers to the processing information P2 in FIG. Since there is an instruction for 1 second in the timer control bit 41, the network management processing circuit 11 measures time with a built-in timer (not shown), and satisfies the condition E2 when the elapsed time exceeds 1 second. Therefore, the state transits to the reset state S3 described in the transition destination bit 44.
In FIG. 4C, there is no description in the transmission processing bit 42 (zero is described), and therefore no NM message is transmitted to the other ECU 30.

According to the present embodiment, since the state transition table T is stored in the EEPROM 12, when the state transition condition and the transition destination of the relay connection unit 10 are changed, it is only necessary to rewrite the state transition table T of the EEPROM 12. The specification of the state transition table T can be changed.
Further, since the network management processing circuit 11 is formed by hardware including a controller circuit, and the state transition table T that is different for each vehicle type is read from the EEPROM 12 via the parameter processing circuit 17, the hardware network management processing circuit 11 Can be shared regardless of the vehicle type.
Furthermore, since the developer can easily grasp the state transition processing operation stored in the EEPROM 12, it becomes easy to verify the operation of the state transition processing.

FIG. 5 shows a second embodiment of the present invention.
In the second embodiment, the state of the limp home standby state S8 is added to the state transition diagram of the first embodiment, the condition E10 for transitioning from the limp home state S6 to the limp home standby state S8, and the limp home A condition E11 for changing from the standby state S8 to the sleep state S7 is set.
The state transition table T includes a spare area in the first embodiment, and in the second embodiment, the limp home standby state S8, the conditions E10 and E11, and the processing information P are the state transition diagram T of the first embodiment. In the spare area.
The limp home standby state S8 is a state provided for standby, and the timer control bit 41 of each processing information P describes a standby time as a timer condition.

With this configuration, after setting the state transition table T during development of the relay connection unit 10, a new timer condition specification is added to verify the operation of the network management function, and the relay connection unit 10 is put into a standby state. When it is necessary to make a transition, a timer condition or the like for the relay connection unit 10 to transition to a standby state can be described in a spare area. For this reason, it is not necessary to newly set a description area, and it is possible to easily add a timer condition specification.
In addition, since another structure and an effect are the same as that of 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

It is a block diagram which shows 1st Embodiment of the relay connection unit which is this invention. It is a state transition diagram of a relay connection unit. (A) is a state transition table, (B) is explanatory drawing of the format of the processing information of a state transition table. (A) is an example of a state transition table, and (B) and (C) are examples of processing information. It is a state transition diagram showing a second embodiment.

Explanation of symbols

10 relay connection unit 11 network management processing circuit 12 EEPROM
13 EEPROM processing circuit 14 Transmission / reception circuit 15 Relay processing circuit 16 Main loop reception circuit 17 Parameter processing circuit 30 Electronic control unit (ECU)
31 Bus 32 Network T State transition table P Processing information

Claims (3)

An in-vehicle relay connection unit that relays messages transmitted and received between the electronic control units belonging to different buses by forming a network by interposing the electronic control units between the respective buses,
A network management processing circuit for executing a network management function;
A storage circuit having a state transition table that parameterizes the transition destination of the state transition condition of the network management function,
The in-vehicle relay connection unit, wherein the network management processing circuit monitors the state transition using the state transition table.   The in-vehicle relay connection unit according to claim 1, wherein the network management processing circuit is formed of an integrated circuit, and the storage circuit is formed of a rewritable nonvolatile memory.   The in-vehicle relay connection unit according to claim 1, wherein the state transition table includes a timer condition for the relay connection unit to transition to a standby state.

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