JP4419192B2 - Automotive control device - Google Patents

Description

  The present invention relates to an automobile control device.

JP-A-61-81235 JP 7-42609 A JP 7-42609 A

  In order to control various devices (controlled elements), an automobile is equipped with an ECU composed of a microprocessor (hardware control main body). In recent years, ECUs mounted on automobiles have been used with large processing capacities (number of parallel processing bits and clock frequency), and one ECU can parallelize multiple applications with different controlled elements in parallel. There is a situation of execution (for example, Patent Documents 1 and 2). The plurality of applications acquire control messages including various control information via the in-vehicle network to which the ECU is connected, and perform control processing for the corresponding controlled elements. In the present specification, “message” is broadly defined as the concept of a data string transferred to the ECU by communication, and is a message in a narrowly-defined sense consisting of linguistically connected character strings. It does not mean only. For example, information on numerical parameters such as temperature and speed detected by the sensor also belongs to the concept of “message”.

  By the way, in a microcomputer that obtains information from the outside via a network, it is rare that the received data is immediately provided to the corresponding application, and in many cases, this is temporarily performed due to factors such as job waiting on the application side. For this purpose, a configuration in which a reception buffer memory is provided between a communication bus and an internal bus of a microcomputer has become common (for example, Patent Document 3).

  By the way, in an automobile control apparatus mainly composed of an ECU, in order to use one ECU for a plurality of function controls, a system in which a plurality of applications corresponding to each function are sequentially activated by a scheduler is often employed. The control message received via the in-vehicle network is temporarily stored in the reception buffer memory. The control message on the reception buffer memory is stored in the application side every execution cycle (hereinafter also referred to as control cycle) defined by the scheduler. Will be acquired. In this case, if the control message reception cycle is equal to or longer than the control cycle, the message can be transferred smoothly from the reception buffer memory. However, depending on the type of application, the control message may be updated. In order to perform it more finely, there is one that uses a control message that is received (updated) at a cycle shorter than the control cycle. In addition, there may be situations in which the control message reception cycle differs among a plurality of applications.

  When a control message with a short cycle as described above is received, conventionally, as a method of acquiring the received control message on the application side, (1) control received by performing polling every execution cycle of the application There are two types: a method for acquiring a message for use and (2) a method for acquiring all the control messages received within the execution cycle by reception interrupt processing. However, in the method of (1), even if a message is received with a short period of time, polling is performed only with a longer period, so even if a control message is received more than once in one control period, it is old. The message is erased by overwriting the reception buffer memory, leading to a problem that the message cannot be used. On the other hand, in the method (2), every time there is reception, a message is acquired through intervening interrupt processing. Therefore, loss of an old message due to data overwriting on the buffer memory can be prevented. There is a problem that the load becomes large and hinders the execution of the control main routine. Also, since the message reception cycle varies, the processing load varies greatly depending on the communication state, and the influence is particularly great when a large number of message receptions are concentrated in a short time when an abnormality occurs.

  An object of the present invention is to reliably perform processing for receiving and acquiring a control message in a cycle shorter than the control cycle, and to significantly reduce the processing load compared to the case of using interrupt processing. An object of the present invention is to provide an automotive control device that can be used.

Means for Solving the Problems and Effects of the Invention

In order to solve the above-described problems, a control apparatus for automobiles of the present invention
A control apparatus for an automobile that realizes functions of a plurality of control means provided corresponding to the controlled elements in order to control electrical operations of the controlled elements on the automobile by a plurality of applications corresponding to the respective control means Because
A CPU which is the execution subject of the application;
RAM as a work area for executing a plurality of applications;
An application activation scheduler that sequentially activates a plurality of applications in a cycle of a reference period in a predetermined order;
A reception buffer provided separately from the RAM for temporarily storing a control message used on an application received by the hardware control entity constituting the control entity of the vehicle control apparatus via the in-vehicle network. Memory,
A message transfer scheduler for transferring a control message stored in the reception buffer memory to a buffer area in the RAM provided in the RAM at a transfer period set shorter than the reference period;
At predetermined timing synchronized with the reference period, to obtain a control message from the RAM buffer region, e Preparations and message acquisition instruction means for instructing the corresponding application, and
As control messages, the latest history adoption type message that uses only the latest message within the execution cycle of the application consisting of the reference cycle, and the all history adoption type message that uses all messages received within the execution cycle. Receive from the in-car network,
The buffer area in the RAM has a first type buffer area in which only the latest control message is overwritten and updated as needed, and a second type buffer area for individually storing received messages in the order of reception time series. It is characterized by that.

  According to the configuration of the automobile control device of the present invention, a plurality of applications for controlling controlled elements on the automobile are sequentially activated in a cycle of a reference period in a predetermined order by an application activation scheduler. In addition, the control parameters used in these applications are temporarily stored in the reception buffer memory, and a RAM buffer area is formed in the RAM forming the application execution area separately from the reception buffer memory. A message transfer scheduler is provided for transferring the control message from the memory to the buffer area in the RAM at a transfer cycle set shorter than the reference cycle. Acquisition of the control message transferred to the buffer area in the RAM is instructed to the corresponding application at a predetermined timing synchronized with the reference period. As a result, even when the reception period of the control parameter is shorter than the reference period that is the application activation period, the message transfer scheduler saves the message in the buffer area in the RAM at the short period. As a result, there is no problem that old messages are erased by overwriting the reception buffer memory as in the method (1) described above. In addition, since the message saving process is performed in the buffer area in the RAM by executing the dedicated message transfer scheduler without using the interrupt process, the load on the interrupt process increases as the reception cycle becomes shorter as in the method (2). Thus, problems that hinder the execution of the control main routine can be effectively avoided.

  The reception buffer memory can be provided with a plurality of storage areas corresponding to the types of control messages. Further, the storage area of the reception buffer memory can be configured to store a corresponding type of control message in such a manner that an old message is overwritten and updated each time it is received. The size of the reception buffer memory can be reduced to simplify the hardware configuration. Also, control messages whose reception cycle is shorter than the reference cycle are transferred from the reception buffer memory to the buffer area in the RAM before being overwritten by the message transfer scheduler, so even if the size of the reception buffer memory is reduced as described above, The loss of message data due to buffer overwriting can be effectively prevented.

  In order to further reduce the size of the reception buffer memory, it is effective to share at least one control message storage area formed in the RAM buffer area with two or more control message storage areas. . In the conventional method, due to such sharing of the storage area, the preceding message is likely to be overwritten and erased by a message of a different type, but if the configuration of the present invention is assumed, the subsequent message Before the message is overwritten, the preceding message is transferred from the reception buffer memory to the buffer area in the RAM by the message transfer scheduler, so that the loss of the message can be prevented, and the size reduction effect of the reception buffer memory can be achieved without any problem. You can enjoy it.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an electrical configuration diagram of an ECU constituting the automobile control apparatus of the present invention. The ECU 1 includes a microprocessor in which a CPU 3, a ROM 5, a RAM 4, and an input / output unit (I / O port) 2 are connected by a bus. In the present embodiment, the ECU 1 is configured as a body system ECU that controls the body system of the automobile, and FIG. 2 shows a schematic architecture thereof. The software installed on the hardware control body composed of a microprocessor is a platform and a control application (hereinafter also simply referred to as an application) for realizing a body function that operates on the platform. In order to distinguish a plurality of applications, symbols A, B, and C are shown (of course, the number of applications is not limited to three as long as there are a plurality of applications: FIG. In the case of n, the illustration is made in a more general form). The platform is for giving a common operating environment to each application even when the base hardware is different. In addition to the basic software (OS) for the application, the platform is linked with the application and hardware. Although it is configured to include an interface program and the like, it is a well-known part conceptually and will not be described in detail.

The application realizes a body function that is a function related to operation of each part of the vehicle by the vehicle user. Specifically, the body system functions include control associated with opening / closing of a door, control associated with opening / closing of a window, control associated with turning on / off a light switch, control of a wireless door lock mechanism employed in a keyless entry system, etc.・ ・ Etc. Specific examples include the following:
-Driver door, passenger door, rear right seat door, rear left seat door, roof lock / unlock, power window operation, etc.
・ Power supply operation for air conditioners, car audio systems, car navigation systems, etc.
-Switch lighting control for room lamp, cockpit lamp, headlight, small lamp, hazard lamp, tail lamp, etc.

  Each application A, B, C is stored in the ROM 5 and is executed by the CPU 3 on the work areas 4A, 4b, 4c corresponding to each application in the RAM 4. The plurality of applications A, B, and C are sequentially started in a cycle of a reference cycle T0 in a predetermined order as shown in FIG. 9 by an application start scheduler formed as a part of the platform function. . At this time, the state management program in the platform collectively manages the state of a series of applications, and determines the control state and performs state transition processing. The state management program defines three states as an application state, that is, a preparation state, a control state, and a control start monitoring state. Each time a series of start processes by the application start scheduler, a signal from each application is defined. Based on this, the state is changed as necessary. It should be noted that the processing cycle by one application can be made to coincide with the reference cycle T0, or in a relatively large application or the like, a processing cycle that is an integral multiple of the reference cycle T0 can be set (for example, a subroutine) For example, if you want to run the application in a different cycle). In the present embodiment, a case in which the processing cycle matches the reference cycle T0 (application execution cycle (control cycle)) is taken as an example.

  The ECU 1 includes a reception buffer memory 7 provided separately from the RAM 4 in order to temporarily store control messages used on the applications A to C received via the in-vehicle network (network bus). ing. As shown in FIG. 10, the control message stored in the reception buffer memory 7 is stored in the RAM buffer area provided in the RAM 4 in the transfer cycle T1 set shorter than the reference cycle T0 by the message transfer scheduler. 4e and 4f. The corresponding application using the control message is instructed to acquire the control message from the RAM buffer areas 4e and 4f (message acquisition instruction means). The function of the message transfer scheduler is realized by the message transfer control program 5d stored in the ROM 5 (the execution area is the work area 4d in the RAM 4). In addition, in this embodiment, the function of the message acquisition command unit is incorporated in the above-described application activation scheduler, but can also be handled as a job in the message transfer control program 5d.

  According to the above configuration, when the reception period T1 of the control parameter is shorter than the reference period T0 that is the application activation period (control period), the message transfer scheduler sends a message in the RAM buffer area in the short period T1. Retreat to 4e, 4f. As a result, there is no problem that the old message is deleted before being acquired on the application side by overwriting the new message in the reception buffer memory 7. Further, since the message saving process is performed in the buffer areas 4e and 4f in the RAM by executing the dedicated message transfer scheduler without using the interrupt process, the interrupt process is repeatedly performed in synchronization with the short reception cycle T1. It is possible to avoid an increase in the processing load due to.

This will be described in more detail below.
As shown in FIG. 3, the reception buffer memory 7 is provided with a plurality of storage areas corresponding to the types (A, B, C) of control messages. When a corresponding type of control message is newly received in the storage area of the reception buffer memory 7, the old control message that has already been written is overwritten and erased. It is effective to share at least one control message storage area formed in the R reception buffer memory 7 with two or more types of control message storage areas. In the conventional method, due to the sharing of the storage area, the preceding message is likely to be overwritten and erased by a message of a different type, but the preceding message is overwritten before the subsequent message is overwritten. By transferring the message from the reception buffer memory 7 to the buffer areas 4e and 4f in the RAM by the message transfer scheduler, it is possible to prevent the loss of the message and enjoy the effect of reducing the size of the reception buffer memory 7 without any problem. .

  In the present embodiment, the reception buffer memory 7 is connected to the network bus via the buffer memory controller 6. The buffer memory controller 6 is interposed between the input / output unit 2 and the network bus, receives a control message transmitted on the network bus, and stores it in the reception buffer memory 7. The control message is serial data, and a message type code for identifying the type of the message is arranged at the head, and the message body is arranged following this. A plurality of control message storage areas (FIG. 3, [0], [1], [2],..., [N−1]) in the reception buffer memory 7 are individually associated with the message type code. Yes. FIG. 6 shows the flow of reception buffer control (processed by the hardware logic in the buffer memory controller 6). The buffer memory controller 6 identifies the message type code (S1) and stores the message type code in the message type code. It is stored in the corresponding storage area (S2, S3). In FIG. 3, the storage area of [n−1] is shared (that is, shared) for storing two types of messages X and Y, but it is arbitrary which storage area is shared by a plurality of messages. In some cases, the entire storage area may be used for a plurality of messages. When two messages of different types are sequentially transferred from the storage area of the shared buffer memory 7 to the buffer area 4e in the RAM at an interval shorter than the reference period T0, the buffer memory 7 for both messages is used. It is desirable to provide a waiting time shorter than the reference cycle T0, which corresponds to the transfer cycle to the buffer area 4e in the RAM, between the reception timings to the above.

  The control message includes the latest history adoption type message in which only the latest message is used within the execution cycle of the application having the reference cycle T0, and the all history adoption type message in which all messages received within the execution cycle are used. Can be received from the in-vehicle network. FIG. 7 shows a conceptual diagram (the configuration of the reception buffer memory 7 is different from that in FIG. 3). Three messages A, B, and C correspond to the latest history adoption type message, and the messages K and X , Y corresponds to the all-history adoption type message.

  The buffer areas 4e and 4f in the RAM receive the first type buffer area 4e (buffer memory for each message: FIG. 4) in which only the latest control message is overwritten and updated as needed, and receive received messages. The second type buffer area 4f is stored separately in time series order. In this way, for the latest history adoption type messages A, B, and C, the latest message can be reliably acquired by overwriting the first type buffer area 4e, and the size of the first type buffer area 4e is also reduced. it can. On the other hand, for all history adopted messages K, X, and Y, the received messages can be individually stored in the second type buffer area 4f in the order of reception time series. As an example of the latest history adoption type message, for example, when a control request is generated, a message including information used for determining whether or not the request can be accepted (for example, on / off states of various SWs). For example, a message to be notified). Moreover, as an example of the all-history adoption type message, a message using the integrated result of received information such as fuel efficiency and vehicle speed for control can be exemplified. Note that these are merely examples, and when a plurality of ECUs receive the same message and use the information for control, the message is referred to as a “latest history adoption type message” depending on the control content of each ECU. Or “all-history adoption type message” may be different.

  In the present embodiment, the second type buffer area 4f is configured as a FIFO (First In First Out) memory shown in FIG. In this way, it is possible to easily realize the function of storing all history adoption type messages K, X, and Y first from the earliest reception time series and retrieving them first from the earliest reception time series. There is no need to perform complicated addressing corresponding to the reception time series in the message storage area.

  On the other hand, the control message receives a long-period update type message having a reception interval equal to or longer than the reference period T0 and a short-period update type message having a reception interval shorter than the reference period T0 from the in-vehicle network. You can also In this case, the transfer scheduler can be configured to selectively transfer the short cycle update type message to the RAM buffer areas 4e and 4f. In FIG. 7, message Ω corresponds to a long-period update type message, and messages A, B, C, K, X, and Y correspond to short-cycle update type messages.

  When the long-period update message Ω is received by the reception buffer memory 7, the message acquisition command means acquires the long-cycle update message Ω from the reception buffer memory 7 at a predetermined timing synchronized with the reference cycle T0. To the corresponding application (first process). On the other hand, when the short cycle update type messages A, B, C, K, X, and Y are received by the reception buffer memory 7, the RAM buffer areas 4e and 4f are set at a predetermined timing synchronized with the reference cycle T0. To obtain a control message from the corresponding application (for the latest history adoption message A, B, C, the second process in which the first type buffer area 4e is designated, the all history adoption message K) , X, and Y, the third process in which the second type buffer area 4f is designated). As a result, it is sufficient to secure the RAM buffer areas 4e and 4f only for the short-cycle update type messages A, B, C, K, X, and Y, which contributes to memory saving and the message transfer process by the transfer scheduler. The load can be reduced.

  In the following description, the long-period update type message Ω is the first type message, the short-cycle update type message and the latest history adoption type messages A, B, and C are the second type message, the short-cycle update type. Messages K, X, and Y that are messages and are all history-adopted messages are also referred to as third-type messages.

  In the present embodiment, a storage area dedicated to long-period update type messages and a storage area dedicated to short-period update type messages are individually provided in the reception buffer memory 7. The function realization processing of the transfer scheduler and message acquisition command means for the long cycle update type message and the function realization processing of the transfer scheduler and message acquisition command means for the short cycle update type message are each unique for each storage area. If it is started, the software configuration can be clarified and simplified, and the processing efficiency is improved. Specifically, in [0], only the message of the type code corresponding to the long cycle update type message Ω is stored, and in the [1] to [n−1], the short cycle update type messages A, B, and C are stored. Only messages of type codes K, X, Y are stored. When instructing each application to acquire a message, for the long-period update type message Ω, the area [0] of the reception buffer memory 7 is always designated as the message acquisition destination, and the short-period update type messages A, B, For C, K, X, and Y, the buffer area in RAM corresponding to the areas [1] to [n-1] of the reception buffer memory 7 should always be designated as the message acquisition destination.

  In addition, the control message can be received from the in-vehicle network a regular update type message having a fixed reception interval and an irregular update type message having an indefinite reception interval. In FIG. 7, messages Ω, A, B, C, K, X, and Y correspond to regular update messages, and message Z corresponds to irregular update messages. The message acquisition command means sends the buffer area 4e in RAM to the corresponding application at a predetermined timing synchronized with the reference period only for the periodic update type messages Ω, A, B, C, K, X, Y. , 4f can be configured to instruct acquisition of a control message.

  In addition, when an irregularly updated message Z (hereinafter also referred to as a fourth type message) is received, acquisition of the irregularly updated message from the reception buffer memory 7 is performed by interrupt processing synchronized with the reception timing. , An interrupt instruction means (function realized by the message transfer control program 5d) for instructing the corresponding application is provided. It is possible to immediately determine whether the received control message is an irregular update type message or not by collating the type code in the buffer memory controller 6 (FIG. 1). If the message is an irregular update type message, the buffer memory controller 6 inputs an interrupt signal to the interrupt terminal INT of the input / output unit 2. The message transfer control program 5d monitors the input to the interrupt terminal INT. If there is an input, the message transfer control program 5d has a storage area (see FIG. [N]) command to obtain the control message Z.

  In the above method, only a predetermined message as the pre-regular update type message Z is instructed to the corresponding application to acquire the irregular update type message by interrupt processing synchronized with the reception timing. For example, by designating a message having a particularly high update priority as the irregular update type message Z, the frequency and reliability of the message content update can be improved. For other periodic update type messages, the transfer scheduler transfers the message to the RAM buffer areas 4e and 4f and instructs the acquisition of messages from the RAM buffer areas 4e and 4f. It is also possible to achieve the effect of avoiding the problem that the processing load increases due to excess.

  FIG. 8 is a flowchart showing an outline of processing of the message transfer control program 5d corresponding to the embodiment of FIG. In S101, the type of the received message is specified from the type code. In the case of the first type message, as shown in FIG. 9, at the beginning of the execution period T0 of the application startup scheduler, message acquisition from the storage area [0] of the reception buffer memory 7 is notified to the corresponding application (first page). One process: In this embodiment, this job is incorporated in the application activation scheduler. However, if it is the former, it is necessary to give a scheduler activation trigger to the message transfer control program 5d side).

  If it is the second type message, the process proceeds from S103 to S108, and the buffer memory controller 7 is instructed to transfer the messages stored in the storage areas [1] to [4] of the reception buffer memory 7, and in S109 Then, the transferred message is stored in the corresponding storage area of the first type buffer area 4e (buffer memory for each message) (second processing: the function of the message transfer scheduler is realized). The execution cycle T1 of the message transfer control program is completed with this, but the cycle T1 shown in FIG. 10 is shorter than the reference cycle T0 that forms the execution cycle of the application activation scheduler of FIG. On the other hand, the process of notifying the corresponding application of message acquisition from the corresponding storage area of the first type buffer area 4e is performed at the top of the application activation scheduler in FIG. 9, and as a result, the execution interval of the notification process is This coincides with the reference period T0, that is, the execution period of the application. The processing for the third type message is the same as that for the second type message except that the storage destination of the transferred message is the second type buffer area 4f (FIFO buffer memory) (first type message). Three treatment). Further, in the case of the fourth type message, the above-described interrupt processing is executed mainly by the buffer memory controller 6 (fourth processing).

  FIG. 12 is a schematic timing chart showing the first to fourth processes in comparison. Since the second process and the third process are transferred and saved to the buffer area in the RAM at a cycle T1 shorter than the reference cycle T0 by the message transfer scheduler, it can be understood that the message reception / acquisition with a short cycle can be handled without any problem. . On the other hand, a special message that requires a shorter message acquisition interval can be handled by the fourth process using the interrupt process.

The block diagram which shows an example of ECU which comprises the control apparatus for motor vehicles of this invention. FIG. 2 is a schematic diagram showing an architecture of the system of FIG. 1. The content conceptual diagram of a reception buffer memory. The content conceptual diagram of the 1st type buffer area which comprises the buffer memory area in RAM. Similarly, the content conceptual diagram of the second type buffer area. The flowchart which shows the flow of a process of reception buffer control. Explanatory drawing of the function principal part in the control apparatus for motor vehicles of FIG. The flowchart which shows the processing flow of the message transfer control program corresponding to FIG. The conceptual diagram of the 1st process of FIG. The conceptual diagram of the 2nd / 3rd process of FIG. The conceptual diagram of the 4th process of FIG. FIG. 8 is a schematic timing diagram for explaining an effect brought about by the function of FIG. 7.

Explanation of symbols

1 ECU (Hardware control subject: Automotive control device)
4 RAM
4e, 4f RAM buffer area 5 ROM
5d Message transfer control program 7 Receive buffer memory

Claims (6)

Vehicle control for realizing a plurality of control means provided corresponding to the controlled elements in order to control electric operations of the controlled elements on the vehicle by a plurality of applications corresponding to the respective control means A device,
A CPU that is the execution subject of the application;
RAM serving as a work area for executing the plurality of applications;
An application activation scheduler that sequentially activates the plurality of applications in a cycle of a reference period in a predetermined order;
In order to temporarily store a control message used on the application, which is received by the hardware control main body constituting the control main body of the vehicle control apparatus, via the in-vehicle network, it is provided separately from the RAM. Receive buffer memory,
A message transfer scheduler for transferring a control message stored in the reception buffer memory to a buffer area in the RAM provided in the RAM at a transfer period set shorter than the reference period;
Message acquisition instruction means for instructing a corresponding application to acquire the control message from the buffer area in the RAM at a predetermined timing synchronized with the reference period ,
As the control message, the latest history adoption type message that uses only the latest message within the execution cycle of the application consisting of the reference cycle, and the entire history adoption that uses all messages received within the execution cycle. Type message from the in-vehicle network,
The buffer area in RAM is a first type buffer area in which only the latest control message is overwritten and updated as needed, and a second type buffer area for individually storing the received messages in the order of reception time series. And a control apparatus for an automobile.   The reception buffer memory is provided with a plurality of storage areas corresponding to the types of the control messages, and the control messages of the corresponding type overwrite and update old messages each time they are received. The vehicle control device according to claim 1, stored in   The vehicle control device according to claim 1 or 2, wherein at least one control message storage area formed in the reception buffer memory is shared by two or more types of control message storage areas. Automobile control system according to any one of claims 1 to 3 configured wherein the two buffer areas in the FIFO memory. As the control message, a long cycle update type message having a reception interval equal to or longer than the reference cycle and a short cycle update type message having a reception interval shorter than the reference cycle are received from the in-vehicle network. The transfer scheduler is configured to selectively transfer the short cycle update type message to the buffer area in the RAM,
When the long-period update type message is received by the reception buffer memory, the message acquisition command means sends the long-period update type message from the reception buffer memory at a predetermined timing synchronized with the reference period. When the corresponding application is instructed to be acquired and the short cycle update type message is received in the reception buffer memory, the buffer is stored in the RAM buffer area at a predetermined timing synchronized with the reference cycle. The automobile control device according to any one of claims 1 to 4 , which instructs a corresponding application to acquire the control message. As the control message, a periodic update type message having a constant reception cycle and an irregular update type message having an indefinite reception cycle are received from the in-vehicle network. Only for the periodic update type message, at a predetermined timing synchronized with the reference period, the corresponding application is instructed to acquire the control message from the buffer area in the RAM,
On the other hand, when the irregularly updated message is received, interrupt command means for commanding the corresponding application to acquire the irregularly updated message from the reception buffer memory by interrupt processing synchronized with the reception timing. The control apparatus for motor vehicles of any one of Claim 1 thru | or 5 provided with these.

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