JPH05307487A - Multi-task monitor - Google Patents

Abstract

PURPOSE:To provide a multi-task monitor which omits useless operation on the multi-task monitor and executes efficiently processing by knowing a task number only at the time of necessity. CONSTITUTION:First of all at a step S1, the value of a stack pointer storing the address value of a stack area is read. Next, at the step S2, it is discriminated an address in what stack area the value of the stack pointer is, and at the following step S3, the task number is fixed in accordance with a judged result, and the useless operation on the multi-task monitor is omitted, and the processing can be executed efficiently.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multitask monitor for controlling a plurality of tasks and performing parallel processing.

[0002]

2. Description of the Related Art Conventionally, in equipment control using a CPU, there is a method using a multitask monitor as one of software control methods for performing parallel processing or pseudo different processing at the same time.

When performing parallel processing using this multitask monitor, it is possible to operate the tasks, which are the flow of each processing, on the same program, but the input / output signals used for processing and the operation itself. In order to change a task with, it was necessary to know which task was performing the program action now.

Therefore, as a method of recognizing a task on a program, a predetermined area is provided in the memory, the task number is written in the area, and the task number is changed every time the task is changed by the multitask monitor. The method of rewriting to the task number of is used.

[0005]

However, in the above-mentioned conventional example, even when the number of times the task number is known on the program is small, the task number is rewritten every time the task is changed by the multitask monitor.
It was doing useless processing.

The present invention has been made to solve the above-mentioned problems, and by knowing the task number only when necessary, unnecessary operation on the multi-task monitor can be omitted.
It is an object to provide a multitask monitor that can efficiently perform processing.

[0007]

[Means for Solving the Problems] and

In order to achieve the above object, the multitask monitor of the present invention has the following configuration. That is, in a multitask monitor that controls a plurality of tasks and performs parallel processing, by providing a processing program with a specifying unit that specifies an active task from a plurality of tasks that are processed in parallel, Useless operations can be omitted and processing can be performed efficiently.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described in detail below with reference to the drawings.

In the multi-task monitor, as shown in FIG. 2, stack areas corresponding to a plurality of tasks 1 to 4 are secured respectively. For example, the data stored in the stack area of task 1 is stored in other task 2 It is configured so that the data cannot be rewritten by .about.4. Then, when suspending the currently running task and starting a new task, the stack area of the next task that has previously fetched the stack pointer value that stores the stack area of the running task I am rewriting to the address. For example, when task 1 is operating, the value of the stack pointer takes a value between the start address A1 and the end address A2 of the stack area reserved for task 1. Similarly, when each of the tasks 2 to 4 is operating, the value of the stack pointer is between the start address and the end address of the stack area of each of the tasks 2 to 4 B1, B2, C1, C.
Take values between 2, D1 and D2, respectively.

Here, for example, the CPU 31 controls a plurality of simultaneously operating units 3A to 3D as shown in FIG. 3 by input / output signals 3a to 3c for information exchange,
When performing parallel processing, the processing of each of the operation units 3A to 3D is executed as tasks 1 to 4, respectively. Then, in each of the tasks 1 to 4, if there is a reentrant processing routine that performs the same processing, in that processing routine, when the input / output signals 3a to 3c are selected and processed according to the task number in operation, the program is executed. You will need to know the task number above.

FIG. 1 is a flow chart showing the processing for determining the task number in this embodiment. First, in step S1, the value of the stack pointer that stores the address value of the stack area is read. next,
In step S2, it is determined in which stack area the value of the stack pointer is, and in step S3,
The task number is decided according to the discrimination result.

As described above, according to this embodiment, it is possible to know the task number when the program requires it, without performing the processing on the multitask monitor.

<Modification 1> FIG. 4 is a diagram showing a task configuration in Modification 1. In the figure, process 4 indicates a process of inputting / outputting data on the program, and P, Q,
R and S are data memories reserved for Task 1, Task 2, Task 3, and Task 4, respectively. In such a configuration, when a plurality of tasks are processing, the data processed by the task 1 is stored in the data memory P reserved for the task 1 or the task 1 stores the data, for example, as in processing 4. When extracting from the data memory P, it is necessary to know which task is currently operating on the program by the task number so as not to be confused with the data memories Q, S and R of other tasks.

Similarly, for task 2, task 3 and task 4, when inputting / outputting data memory contents,
It is necessary to know the task number so that it will not be confused with the data of other tasks.

At this time, by performing the processing of the flowchart shown in FIG. 1, the task number can be known from the value of the stack pointer when it is necessary in the program without performing the processing in the multitask monitor. ..

<Modification 2> FIG. 5 is a diagram showing a task configuration in Modification 2. In the figure, process 5 indicates a process before branching, and includes process 51, process 52, process 53, and process 5.
Reference numeral 4 indicates processing of branch words.

In such a configuration, when the same program is processed by using a plurality of tasks, if different processing is desired to be performed from the middle, for example, as shown in FIG. Let the process take place, and then process 5
When it is desired to perform four types of processing, such as 1, processing 52, processing 53, and processing 54, the task corresponding to each processing 51 to 54 is set, and after the processing 5 ends, each task The corresponding process may be selected from among the processes 51 to 54, but it is necessary to know the task number when selecting the process on the program.

At this time, by performing the processing of the flowchart shown in FIG. 1, the task number can be known from the value of the stack pointer when necessary in the program without performing the processing on the multitask monitor. ..

[0019]

As described above, according to the present invention,
By knowing the task number only when necessary, it is possible to eliminate wasteful operations on the multitask monitor and perform processing efficiently.

[Brief description of drawings]

FIG. 1 is a flowchart showing a process of confirming a task number in this embodiment.

FIG. 2 is a diagram showing a stack area reserved for each task in order to use a multitask monitor.

FIG. 3 is a diagram showing a task configuration according to the present embodiment.

FIG. 4 is a diagram showing a task configuration according to a modified example 1.

FIG. 5 is a diagram showing a task configuration according to a modification 2;

Claims (1)

[Claims] 1. A multitask monitor that controls a plurality of tasks and performs parallel processing, characterized in that the processing program has specifying means for specifying an operating task from the plurality of tasks to be processed in parallel. Task monitor.