JP2002049498A - Task activation control method - Google Patents

Abstract

(57) [Problem] To provide a task activation control method capable of improving the activation processing efficiency of tasks having the same activation cycle and different priorities in automatic control by a computer in vehicle control or the like. SOLUTION: A priority list in which tasks are arranged in order of priority according to the priority set for each task is set, a task start request in which a start request occurs at the same start timing is set, and the set start request is set. On the other hand, the boot process is executed in the order of the priority set in the priority list, and a plurality of tasks having the same boot timing are booted by one boot request.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a task activation control method in automatic control by a computer, and more particularly, to a task activation control method.
The present invention relates to a task activation control method for controlling activation of a plurality of tasks having unique task activation timings in electronic automatic control of an automobile engine or the like.

[0002]

2. Description of the Related Art In recent years, microcomputers have been introduced for controlling automobiles, and it has become possible to control engines, power trains and the like with high accuracy. As a result, software development of microcomputers has become a major player in the development of automotive control systems,
It is important to improve the efficiency of the processing on the control algorithm.

[0003] In an engine control system using a microcomputer, a task of performing an equal time interval processing for discrete value processing based on digital control theory, such as a calculation of an intake air amount and a fuel injection amount, and an ignition timer set. As described above, there are a plurality of tasks for each control target such as a task of performing a process based on crank position information which is a state quantity of the control target, and these tasks are usually performed at predetermined time intervals and at predetermined crank angles. Interrupts are executed, and various proposals have conventionally been made to appropriately execute a plurality of interrupt processes.

For example, Japanese Patent Laid-Open Publication No. 6-200820 discloses that a flag indicating an interrupt request of each task is created with a priority, and the number of interrupt requests that occur repeatedly before the end of the task at each priority. And executes the task indicated by the flag at each priority from the higher priority to the lower priority by the stored interrupt request count.

[0005] In addition to the above, for example, Japanese Patent Application Laid-Open No. 10-105416,
No. 105418 and the like.

[0006]

However, high value-added automobile control and low price control units have been developed.
If multiple controls are performed by a single microcomputer, the tolerance for control delay differs depending on the control target.To achieve more precise control, multiple tasks must be started individually as described above. Not only tasks that are executed in a cycle but also tasks that are started in the same startup cycle need to have a unique priority.

Further, since the hardware conditions (cost, ROM, RAM capacity) of the vehicle control device are severe, and since it is a real-time control, the demand for the response speed is also severe, so that most of the CPU resources are used for each control. And the task activation process needs to be as light as possible.

On the other hand, in the above-mentioned prior art, since the activation cycle is measured independently for each task, when a task having the same activation cycle is newly created or added, the same activation cycle is used. Despite the cycle, a new process of measuring the startup cycle and determining the startup request is required.

The present invention has been made in view of the above circumstances, and provides a task activation control method capable of improving the activation processing efficiency of tasks having the same activation cycle and different priorities in automatic control by a computer in vehicle control or the like. It is intended to be.

[0010]

In order to achieve the above object, a task activation control method according to the present invention has a unique task activation timing by an interrupt process activated at a predetermined timing by automatic control by a computer. In a task activation control method for executing activation processing for a plurality of tasks, a priority list in which tasks are arranged in priority order according to the priority set for each task is set, and activation requests are generated at the same activation timing. A task start request is set, a start process is executed for the set start request in the order of the priority set in the priority list, and a plurality of tasks having the same start timing are started by a single start request. Features. Thus, a plurality of tasks having the same start timing can be started efficiently by one start request.

In the task activation control method according to the present invention, there is a task activation timing based on an interrupt process activated by a timer at a predetermined time interval, and the activation request can be set at a different time interval for each task. it can. Thus, each task can be activated in a time cycle.

In this case, there is one basic counter counted by an interrupt process started by a timer at a constant basic time interval, and a counter for determining a period is provided for each task activation period. When the cycle determination counters match, the start request is set by detecting that the cycle is the start cycle, and after the detection, the base count value and the counter value for the cycle are added to update the cycle determination counter. , The next start timing can be set.

Thus, only the basic counter needs to be counted at the basic time interval, and the cycle determination counter is updated at each activation cycle interval. Therefore, a higher speed than updating the counter for each cycle at the basic time interval is obtained. The start cycle can be detected.

Further, in the task activation control method according to the present invention, the task activation timing is based on an interrupt process activated by the state quantity of the controlled object, and the activation request is set with a different state quantity for each task. be able to. Thus, each task can be started in synchronization with the state quantity of the control target, for example, in synchronization with the crank angle of the engine.

In the task activation control method according to the present invention, the task activation timing includes a task triggered by an external event that occurs irregularly, and the activation request can be set in event synchronization. This allows event synchronization,
Each task can be started.

The task activation control method according to the present invention has various activation timings as described above, and an activation request can be set according to the activation timings.

[0017]

FIG. 1 shows an overall system of an internal combustion engine to which a task activation control method according to the present invention is applied.

The engine body 1 has a piston 3 in a combustion chamber 2 of each cylinder, and the piston 3 is connected to a connecting rod 4
To the crankshaft 5.

An intake port 6 of the engine body 1 has an air cleaner 7, an air flow meter 8, a throttle body 10 containing an electric throttle valve 9, a collector 11, and an intake pipe 1.
2 are connected, and air is sucked into each combustion chamber 2 from the intake port 6 of each cylinder through these. Intake port 6
Is opened and closed by a camshaft driven intake valve 13.

The engine body 1 is provided with an in-cylinder injector 14 and a spark plug 15 for each cylinder.

An exhaust pipe 17 and a catalytic converter 18 are connected to an exhaust port 16 of the engine body 1, through which exhaust gas is discharged. The exhaust port 18 is opened and closed by an exhaust valve 19 driven by a camshaft.

As a fuel supply device, an electric fuel pump 21 for pumping fuel such as gasoline from a fuel tank 20 to first pressurize the fuel,
A high-pressure fuel pump 22 for the next pressurization is provided, and the high-pressure fuel for the second pressurization is supplied to a fuel system provided with an injector.

As shown in FIG. 2, the control unit 50 for controlling the engine includes a CPU 51, an RO,
I / O including M52, RAM53, A / D converter, etc.
It is a microcomputer type composed of a boat 54 and the like, receives signals from various sensors and the like for detecting the operating state of the engine as inputs, executes predetermined arithmetic processing, and performs various arithmetic operations calculated as the arithmetic results. , And supplies a predetermined control signal to the injector 14, the ignition coil 48, and the electric throttle drive unit 49 to execute fuel supply amount control, ignition timing control, and the like.

The sensors for inputting signals indicating the operating state of the engine to the control unit 50 include a crank angle sensor 55, a throttle sensor 56, an accelerator sensor 57, a brake switch 58, an air flow meter (air flow sensor) 8, a cooling water temperature sensor. 59, a fuel pressure sensor 60, a vehicle speed sensor 61, an auto cruise main switch 62, an air-fuel ratio sensor 63, and the like.

In the above-described engine control, the microcomputer 50 executes various programs for each item such as signal input processing from each sensor, engine speed calculation, intake air amount calculation, fuel injection amount calculation, and ignition timing calculation. Is efficiently executed under the control of one operating system (hereinafter abbreviated as OS). The management functions of this OS include (1-1) Equal time interval control of tasks (1-2) Immediate activation of tasks (1-3) Priority control of tasks (1-4) Restrictions specific to each task (1-5) Stack usage monitoring function (1-6) Abnormal interrupt operation monitoring function, etc. to improve the control development environment and maximize the limited CPU capacity To achieve as much as possible the equal time interval processing that is the basis of digital control theory.

The equal time interval processing is based on a periodic interruption every 1 ms, for example, and is based on 1, 2, 4, 10, 20, 40,
Nine types of equal time interval interrupt tasks are prepared at intervals of 80, 160, and 320 ms, and are triggered by the crank angle position, which is the state quantity (physical quantity) of the controlled object, or an external event that occurs irregularly. For example, an event task is prepared as a process synchronized with an arbitrary control timing.

The equal time interval interrupt task and the event task each have a task control table 300. As shown in FIG. 3, the task control table 300 includes, for each task, a priority, a start cycle / event, a data item of a start request, a next priority pointer, a next start cycle / event pointer, and program registration. It has a pointer to the table 310.

In the program registration table 310, the entry addresses of all programs executed by the task are set in the order of execution as an array, and delimiter data (value 0) is set in the last element. For example, the entry address of the EGI program 320 is registered at the EGI entrance of the program registration table 310 (see FIG. 3).

Each program operating under the OS described above registers a program entry address in the program registration table 310 corresponding to each task, thereby obtaining a desired priority / priority.
The start cycle and program execution order can be easily set, and development and debugging for each function can be easily performed.

As shown in FIG. 4, each task has a level 254 from the high priority side to the low priority side.
Priority is given to 256 levels of 0 to 0, and as shown in a task 504 in FIG. 15, a low-priority task is divided and processed for a high-priority task, and multiple waiting processing of each task is performed. .

A task is divided into 16 stack shared task groups by a quotient obtained by dividing the task priority by 16, for example.
(Priority levels 254 to 240, 239 to 224, ...
, 15 to 0), and the tasks included in the same stack sharing task group do not perform the division processing and share the stack to save memory. For example, in the example shown in FIG. 4, the tasks of the priority levels 254 to 240 included in the stack sharing task group A share the stack # 1. Also, in FIG.
~ 502 are included in the same stack sharing task group,
It is not split by each other's operation.

The priority assignment of each task is set as shown in FIG. 5 as one specific example. In this specific example, tasks 501-503, 504-505, 508-
510, 513 to 515 are the same stack shared task group, and share the stack. Information on the priority assignment of each task is stored in the RAM 52 as a task priority assignment table 500.

Based on the task priority assignment table 500, a priority list 600, a start cycle list 700, and an event list 800 are created.

As shown in FIG. 6, the priority list 600 is a linear list in which task control tables of all tasks under OS management are linked by pointers in order of priority (level), in other words, This is a list in which the tasks are arranged in order of priority based on the priority set for each task, and is used to start the tasks having an activation request in order of priority.

As shown in FIG. 7, the activation cycle list 700 is a linear list in which task control tables of the same activation cycle are linked by pointers, and searches for tasks of different priorities in the same activation cycle at high speed. Used to store the activation request. For example, in the 2 ms cycle, task control tables of tasks 503 and 504 having different priorities are connected in the same cycle. Both the task 507 and the task 508 have a period of 10 ms, but are connected as different periods by shifting the period phase to achieve load distribution.

The start-up cycle list 700 includes a cycle determination counter 720 for detecting a start-up timing of each cycle by a cycle measurement counter (basic counter) 710 as a basis of the start-up cycle measurement for each task in the start-up cycle. Is defined.

As shown in FIG. 8, the event list 800 is a linear list in which task control tables activated by the same event are linked by a pointer. Used to store startup requests.

Next, various functions of the OS in the control unit 50 will be described with reference to the flowcharts of FIGS.

When the ignition switch is turned on and the power is turned on to the system, a reset interrupt accompanying the reset is activated, and various initializations are performed. In this reset interrupt, as shown in FIG. 9, each task control table 300 is initialized (step 901) and the priority list 600 is initialized (step 90) based on each priority assignment table 500.
2), initialization of the activation cycle list 700 (Step 903), initialization of the event list 800 (Step 904), and other initialization (Step 905) are performed. In the initialization of the startup cycle list 700, the cycle measurement counter 710 is cleared, and the cycle determination counter 720 for each startup cycle is initialized.

Task control table 300, priority list 600, start cycle list 700, event list 800
After the initialization is completed, a timer for activating a periodic interrupt is activated every 1 ms, and the periodic interrupt is permitted (step 906). Thereafter, the background task enters an execution state (step 907).

Next, FIG. 1 shows a periodic interrupt every 1 ms.
0 will be described. In this periodic interrupt, the register is saved (step 1001), and the low-priority task can be divided. Thereafter, the next periodic interrupt is set (step 1002). This processing is coding dependent on the CPU 51, and clears an interrupt flag, resets the next interrupt timer value, and the like. After that, the activation request setting routine 1003 is called.

The activation request setting routine is a process for writing an activation request to the task control table 300 using the activation cycle list 700.
This will be described with reference to FIG. First, the cycle measurement counter 710
Is incremented (step 1101). this is,
This is a basic counter for detecting whether or not it is the activation cycle of each task, and is incremented by 1 at regular interrupts every 1 ms.

Next, the leading cycle of the starting cycle list 700 is selected (step 1102). In each cycle, a cycle determination counter 720 is provided for detecting the activation timing, and the cycle measurement counter 710 and the cycle determination counter 720 are compared (step 1103). If the cycle measurement counter 710 and the cycle determination counter 720 do not match (No at Step 1103), the next cycle is selected from the start cycle list 700 (Step 1109).
It is determined whether there is a next cycle (step 1110). If there is a next cycle, the process returns to step 1103, and if there is no next cycle, this routine ends.

When the period measurement counter 710 and the period determination counter 720 match (Yes at step 1103), it is possible to detect the start timing of the period, and the period determination counter 720 of the period stores the counter value for the period. (Step 110)
4).

Next, the first task is selected from the cycle of the startup cycle list 700 (step 1105), and after it is determined that there is a task (Yes at step 1106), an activation request of the task control list 300 of the task is set (step 1105). 1
107). Next, the next task is selected from the cycle of the activation cycle list 700 (step 1008), and if there is a next task (Yes at step 1106), an activation request is also set in the task control list 300 of that task (step 1008). 1107). When the activation request setting process for all tasks in the cycle is completed, it is determined that there is no task (No at Step 1107), and the next cycle is selected from the activation cycle list 700 (Step 1109).

When the activation request setting process for all cycles is completed, it is determined that there is no next cycle (No at Step 1110), and
The activation request setting routine ends, and the routine returns to the 1 ms periodic interrupt (FIG. 10).

When the activation request setting routine ends, the highest priority task is selected from the priority list 600 (step 1004). Next, it is determined whether or not there is a task (step 1005).
5 is affirmative), it is determined whether or not the stack sharing task is being executed (step 1006). The stack sharing task is a mechanism for saving stack memory. When the task is being executed (Yes at step 1006), the register is restored with priority given to the task being executed (step 1010).
The 1 ms periodic interrupt ends.

If the stack sharing task is not being executed (No at Step 1006), it is next determined whether or not there is an activation request for the task (Step 1007). If there is no activation request (No at Step 1007), the task of the next priority is selected from the priority list 600 (Step 1009), and the process returns to Step 1005. In contrast,
If there is an activation request (Yes at Step 1007), a task activation processing routine is called (Step 100).
8).

The task start processing routine is a routine for starting a program registered in a task by the program registration table 310. The task activation processing routine will be described with reference to FIG. First, the execution flag of the task is set (step 1201), and the interrupt mask of the 1 ms periodic interrupt is released (step 1202).

Next, the first program is selected from the program registration table 310 (step 1203). If there is a program (Yes at Step 1204), the program is called (Step 1205). The processing contents of this program are arbitrarily created by the user. When the program ends, the next program is selected from the program registration table 310 (step 1206), and the process returns to step 1204.

When all the programs of the task have been started, it is determined that there is no program (No at Step 1204), and the interrupt mask for the 1 ms periodic interrupt is reset (Step 1207). Next, the task execution flag is cleared (step 1208), and the activation request of the task control table 300 of the task is cleared. Next, the contents of the external output port output buffer updated by the task are reflected on the output port (step 1210), the task activation processing routine is terminated, and the routine returns to the 1 ms periodic interrupt (see FIG. 10).

When the task activation processing routine ends, the task of the next priority is selected from the priority list 600 (step 1009), and the process returns to step 1005. When all priorities have been processed, it is determined that there is no task (No at Step 1005), the register is restored (Step 1010), the 1 ms periodic interrupt is ended, and the process returns to the background task (Step 907).

Next, the event interrupt activation routine will be described with reference to FIG. An event interrupt is an interrupt for starting a task that generates a start request at a start timing other than the 1 ms periodic interrupt, such as a crank angle synchronization of the engine to be controlled, and the priority is set so that the task is processed within the interrupt such as the crank angle interrupt. Is not high,
Used when running at a lower priority.

When an event interrupt activation routine is called by a user-created program that has detected an event, first, the first event in the event list 800 is selected (step 1301). Next, it is determined whether or not there is an event (Step 1302). If there is no event (No at Step 1302), the event interrupt activation routine ends, and the program returns to the program created by the user. If there is an event (Yes at Step 1302), it is determined whether or not the event is an event requested by the user program (Step 1303).
, The next event is selected (step 1304), and the process returns to step 1302.

On the other hand, if the event is a request event (Yes at Step 1303), the leading task of the event is selected (Step 1305), and it is determined whether there is a task (Step 1306). If there is a task (Yes at step 1306), the task control table 30
0 is set (Step 1307), the next task of the event is selected from the event list 800 (Step 1308), and the process returns to Step 1306.

When the setting of the activation request for all tasks of the event is completed, it is determined that there is no task (No at Step 1306), and an event interrupt is activated (Step 130).
9). The activation of the event interrupt is realized, for example, by setting the interrupt permission. Thereafter, the event interrupt activation routine ends, and the program returns to the program created by the user.

Next, an event interrupt will be described with reference to FIG. Event interruption steps 1401 and 140
The processing contents of 3 to 1409 are common to steps 1001 and 1004 to 1010 of the 1 ms interrupt processing.

In the event interrupt, first, the register is saved (step 1401), and the low-priority task can be divided. After that, the event interruption is prohibited (step 1402).

Next, as in the case of the 1 ms periodic interrupt, the tasks requested to be activated are activated in the order of priority using the priority list 600 (steps 1403 to 1408). When all tasks have been started, the registers are restored (step 1).
409), end the event interrupt, and return to the background task (step 907).

As described above, since the activation requests of the tasks whose activation requests occur at the same activation timing are set, and the activation processes are executed in the priority order set in the priority list in response to the set activation requests, A plurality of tasks having the same activation timing can be activated by one activation request.

As described above, one embodiment of the present invention has been described in detail. However, the present invention is not limited to the above embodiment, without departing from the spirit of the present invention described in the appended claims. Various changes can be made in the design. For example, the task activation control method according to the present invention is not limited to vehicle engine control, but can be applied as a task activation control method for automatic control of a power train of a vehicle including a transmission. Furthermore,
The present invention can be applied as a task activation control method for automatic control of various devices controlled by computers such as ships, home appliances, etc., as well as automobiles.

[0062]

As described above, according to the task activation control method of the present invention, a priority list in which tasks are arranged in priority order according to the priority set for each task is set, and at the same activation timing. A start request of the task in which the start request occurs is set, and a start process is executed for the set start request in the order of the priority set in the priority list,
Since a plurality of tasks having the same activation timing are activated by one activation request, the activation processing can be sped up. In addition, by giving a degree of freedom to the registration of the task start cycle and the priority, the usability of the user can be improved, and an increase in the start processing time according to the degree of freedom of the registration can be minimized. .

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an overall system of an internal combustion engine to which a task activation control method according to the present invention is applied.

FIG. 2 is a block diagram showing a control system of an internal combustion engine to which the task activation control method according to the present invention is applied.

FIG. 3 is a structural diagram of a task control table and a program registration table used in implementing the task activation control method according to the present invention.

FIG. 4 is an explanatory diagram showing correspondence between task priorities and stack areas.

FIG. 5 is a structural diagram of a task priority assignment table showing priority assignment in the present embodiment.

FIG. 6 is a structural diagram of a priority list used in the implementation of the task activation control method according to the present invention.

FIG. 7 is a structural diagram of an activation cycle list used in the execution of the task activation control method according to the present invention.

FIG. 8 is a structural diagram of an event list used in implementing the task activation control method according to the present invention.

FIG. 9 is a flowchart of a reset interrupt in the task activation control method according to the present invention.

FIG. 10 shows a task activation control method 1 according to the present invention.
10 is a flowchart of an ms periodic interrupt.

FIG. 11 is a flowchart of an activation request setting routine in the task activation control method according to the present invention.

FIG. 12 is a flowchart of a task activation processing routine in the task activation control method according to the present invention.

FIG. 13 is a flowchart of an event interrupt activation routine in the task activation control method according to the present invention.

FIG. 14 is a flowchart of an event interrupt in the task activation control method according to the present invention.

FIG. 15 is an explanatory diagram showing an execution state of a task.

[Explanation of symbols]

 Reference Signs List 50 control unit 300 task control table 500 task priority assignment table 600 priority list 700 activation cycle list 710 cycle measurement counter 720 cycle determination counter 800 event list

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Matsuo Amano 2520 Oji Takaba, Hitachinaka-shi, Ibaraki F-term in the Automotive Equipment Group, Hitachi, Ltd. (Reference) 3G084 BA05 BA13 BA15 BA16 BA17 EB04 EB05 EB10 EC01 FA05 FA06 FA07 FA10 FA38 5B098 AA05 BA04 FF04 FF08 GA04 GC03 GC05

Claims (6)

[Claims] 1. A task start control method for executing start processing for a plurality of tasks having unique task start timings by interrupt processing started at a predetermined timing by automatic control by a computer. A priority list in which tasks are arranged in the order of priority according to the priorities set, a start request for a task that generates a start request at the same start timing is set, and the set start request is set in the priority list. A task activation control method, wherein the activation processing is executed in the order of priority and a plurality of tasks having the same activation timing are activated by one activation request. 2. The task activation control method according to claim 1, wherein the activation request is set at a different time interval for each task by an interrupt process activated by a timer at a constant basic time interval. 3. A method according to claim 1, further comprising: a basic counter counted by an interrupt process started by a timer at a constant basic time interval, a counter for determining a period for each task activation period, and a counter for determining the period. The start request is set by detecting that the cycle is the start cycle when the counters match, and the start request is set.After the detection, the base counter value and the counter value for the cycle are added to update the cycle determination counter, 3. The task priority control method according to claim 2, wherein a next start timing is set. . 4. The task activation control method according to claim 1, wherein the activation request is set with a different amount of state for each task by an interrupt process activated according to the amount of state of the control target. 5. The task activation control method according to claim 1, wherein the activation request is set synchronously with an event triggered by an external event occurring irregularly. 6. An interrupt process started by a timer at a fixed basic time interval, the start request is set at a different time interval for each task, and each task is started by an interrupt process started by a state quantity of a control object. 2. The task activation control method according to claim 1, wherein the activation request is set with different state quantities, and the activation request is set synchronously with an event triggered by an external event occurring irregularly.