JP2880658B2 - Runaway detection device for multitask program - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for detecting runaway of a multitask program.

[0002]

2. Description of the Related Art In recent years, in an apparatus using a microcomputer, a program is divided into a plurality of task programs, each task program is started and executed at a different cycle, and as a result, a certain predetermined control is executed. The so-called multitask processing method is adopted. Such a device is provided with a watchdog timer for detecting a program runaway. This watchdog timer does not output anything while the watchdog pulse is input at a predetermined time interval or less, but does not output any signal as it does not run away. A reset pulse is output to enable runaway detection. This watchdog pulse is output when it passes a runaway detection program that is frequently inserted in the middle of each task program (inserted one after another within the predetermined time interval). .

However, in such a runaway detection method, even if, for example, a runaway occurs in a task 2 program during a task 1 program processing, for example, a watchdog pulse is generated when a task 2 runaway detection program passes. Because it outputs, it is assumed that runaway has not occurred.

Therefore, a proposal for solving such a problem has been made in a program runaway detection method described in Japanese Patent Application Laid-Open No. 3-288942. Japanese Unexamined Patent Publication No. 3-288
The program runaway detection method described in Japanese Patent No. 942 checks whether or not the task processing of each task program is executed normally. If the execution of each task processing is performed normally, By performing a predetermined change in the contents of the data set means provided corresponding to the above, and by checking the contents of these data set means at the time of executing a predetermined task program, all the task programs can be normally executed. In this case, it is detected whether or not the operation is performed.

[0005]

However, the program runaway detection method described in Japanese Patent Application Laid-Open No. 3-288942 has the following problems. That is, every time each task is started, it is necessary to perform a process of checking whether each task is normal, perform a data set process, and further perform a process of checking whether all tasks are normal based on these data. Therefore, a watchdog pulse is output within a predetermined time interval (of course, when it is determined to be normal)
Actually has the problem that the execution time of the task program must be shortened.

In actual start-up, there may be a task that is suspended or stopped, and in such a case, a runaway is determined in the check processing flow of all tasks. There is a problem in that a check program for paused or stopped tasks must be provided in the check processing flow of all the tasks, and thus the determination becomes complicated.

Therefore, the present invention provides a runaway detection device for a multitask program in which runaway detection of a task program can be performed in a short time, the execution time of the task program can be lengthened, and a program for judging a suspended or stopped task is unnecessary. The purpose is to provide.

[0008]

The first object of the present invention is to provide a multitask program runaway detection device which divides a program into a plurality of task programs and executes each task program in a predetermined order. An apparatus for detecting a runaway of a multi-task program, comprising: a plurality of task program storage means for storing a task program; and the task program stored in the task program storage means being converted to a task program designated by the command means. Switching means for switching and this switching means
At the time of switching by, it is determined whether or not the program address based on the task program that was being executed before the switching is within the range of the program address of the task program that was specified before the switching. Means for determining that a runaway has occurred if the determination is made.

In order to achieve the above object, a runaway detecting device for a multitask program according to a second means includes, in addition to the first means, a storage means for storing at least a program address at the time of task program switching as a standby program address. If the determining means determines that the program address based on the task program being executed before the switching is within the range of the program address of the task program specified before the switching , the switching is performed by the switching means. Executing means for shifting to a standby program address in the task program and executing the program.

[0010]

According to the multitask program runaway detecting device in the first means, when the instruction program specifies the task program, the switching means changes the running task program to the specified task program. At this time, the determination means determines whether or not the program address based on the task program executed before the switching is within the range of the program address of the task program designated before the switching. If it is determined that the runaway is not within the range, it is determined that a runaway has occurred, and a runaway is detected by focusing only on the task program that was being executed.

Further, according to the multitask program runaway detecting device in the second means, at the time of switching, at least the program address at the time of task program switching is stored as a standby program address by the storage means, If it is determined that the program address based on the task program being executed before the switching is within the range of the program address of the task program specified before the switching, the execution means switches the program address according to the switching means. The program shifts to the standby program address in the task program that has been executed and the program is executed.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the entire configuration of a multi-task program runaway detection device according to an embodiment of the present invention.
For example, it is applied to a magnetic card reader.

As shown in FIG. 1, a multitask program runaway detection apparatus 20 of the present embodiment includes a plurality of task program storage units 1 to
4, a command means 5 for sequentially designating task programs to be executed in accordance with a predetermined order determined in advance, and a task program stored in the task program storage means 1 to 4 is designated from the command means 5. Switching means (dispatcher) 6 for switching according to the task program
And a program address at the time of switching task programs by the switching means 6 (a program address to be executed next to the last program executed; details will be described later) as a standby program address, and a register, flag ( FLG), a storage means 7 for storing a stack pointer (SP), etc., and a program address (PC) based on the task program being executed, for example, a program address added to the last program address being executed (storage means) 7
Is the same as the program address stored in the task program) is within the program address range of the specified task program. If the dog pulse is not output for a predetermined time or more, and if it is determined that it is within the range, a watchdog pulse is output as not running out (this output is actually used to determine whether there is runaway as described later). (Because it can be detected in a short time, it is performed at a predetermined time interval or less.) The judgment means 8 and the task program to be executed next switched by the switching means 6 The main part is constituted by an execution unit 9 for executing the program by using a register, a flag, a stack pointer, and the like stored in the storage unit 7 after shifting to the program address.

When the standby program address of the task program is not stored in the storage means 7 when the execution means 9 executes the task program, the first program address of the task program is changed to the standby program address. It is configured so that

The execution means 9 includes, for example, a sensor 1 for detecting a card position and inputting the position information.
2 is connected from the outside, and in the execution means 9,
Program processing is performed using this position information.

The execution means 9 includes, for example, a drive circuit 13 for driving a motor 14, a solenoid 16 for controlling a mechanism, and a write circuit 15 which are controlled by a program process using the position information. A warning means 11 for notifying runaway of the program by blinking of an alarm lamp or the like is also connected to the outside.

Further, while the watchdog pulse is input at a predetermined time interval or less, the determination means 8 does not output anything because the runaway does not occur. On the other hand, when the watchdog pulse is interrupted for the predetermined time or more, the runaway occurs. Watchdog reset IC 10 that outputs reset pulse
Is connected to the outside.

The execution means 9 is connected to the watchdog reset IC 10, and when no reset pulse is input, the execution means 9 is switched by the switching means 6 as described above. The task program to be executed is shifted to the next standby program address to be executed stored in the storage means 7 and executed using the registers, flags, stack pointers and the like stored in the storage means 7. On the other hand, when a reset pulse is input, the program is determined to be out of control, the execution of the program is stopped, and the warning means 11 is driven.

Next, the processing of the runaway detecting device for a multitask program configured as described above will be described. FIG. 2 is a flowchart showing the processing of each task program in association with a program address, and FIG. 3 is a flowchart showing a runaway detection procedure executed by the present invention.

Each task program is shown in FIG.
As shown in (c), each task process is performed, and the task 1 is, for example, from address 1000h to 1FFFFh.
The task program is completed by performing the process up to the address, the task 2 performs the process from the address 2000h to the address 2FFFFh, and the task 3 performs the process from the address 3000h to the address 3FFFh, for example. ing

First, if a task program is designated, for example, if task 1 is designated, the processing of task 1 is performed in the order of program addresses until the next task program is designated.

Here, when the next task program is designated during execution of the program of task 1, for example, if task 3 is designated, the task program is switched from task 1 to task 3. The program address of No. 1 is set to a program address which is added to the most recently executed program address (this program address is set to, for example, 1001h for the following description).
Then, the process proceeds to the flowchart shown in FIG. 3. First, in step 1, the program address (1001h) to be executed next to the program executed last in task 1 that has been executed is stored (evacuated) as the standby program address. ), And also stores a register, a flag, a stack pointer, and the like of the task 1 being executed. That is, when the task 1 is designated next time, the data necessary for continuously executing the program of the task 1 is stored.

Then, the process proceeds to step 2, and in step 2, it is determined whether the executed task is 1 or not.
If the executed task is not 1, the process proceeds to step 3. In step 3, it is determined whether the executed task is 2 or not. If the executed task is not 2, the process proceeds to step 4. In step 4, it is determined whether or not the number of executed tasks is 3. In this way, the same determination is repeated until the task that has been executed is applicable.

In this embodiment, since the executed task is 1, the process proceeds from step 2 to step 5, where the stored standby program address (address 1001h) is specified. It is determined whether or not the program address of task 1 is within the range of addresses 1000h to 1FFFh, and the range of addresses 1000h to 1FFFh is determined.
If it is determined that the standby program address is not in the address (actually, the standby program address 1001h is in the range of 1000h to 1FFFFh, but here, for convenience of explanation, the standby program address is set to only 2002h and the range of 1000h to 1FFFh If the address is not within the address), it is determined that the program 1 has not actually been performed and the program has runaway, and the process proceeds to step 8. In step 8, a watchdog pulse is sent to the watchdog reset IC 10 for a predetermined time. Output a reset pulse without sending
Upon receiving the reset pulse, for example, the program is stopped and an alarm lamp or the like is blinked to notify the program of runaway.

On the other hand, in step 5, the stored standby program address (address 1001h) is the range of the program address of task 1 from 1000h to 1FF where the designated address is designated.
If it is determined that it is within the address Fh, the task 1
It is determined that the runaway has not occurred and the program proceeds to step 6. In step 6, the watchdog reset IC 10 outputs a watchdog pulse so that the reset pulse is not output, proceeds to step 7, and stores in step 7 Then, the standby program address of the designated task program to be executed next, the register, the flag, the stack pointer, and the like are restored.

In this embodiment, since the standby program address of the task 3, the register, the flag, the stack pointer, and the like have not been stored yet, as described above,
The runaway detection flow is ended with the first program address of the task 3 program as the standby program address, and the program shifts to the task 3 program shown in FIG. 2C. Perform processing.

If, for example, task 1 is specified during the processing of task 3 in the order of the program addresses, the process moves to the flowchart shown in FIG. Execute Step 2. Here, since the task program being executed is task 3, the process proceeds from step 2 to steps 3, 4, and 10. In step 10, the same determination as in step 5 is performed.
The range of the program address of the task 3 for which the standby program address stored in step 1 was specified, 3000h
It is determined whether or not the address is within the range from address 3FFh to address 3
If it is determined that the address is not within the range from address 000h to address 3FFFFh, the process proceeds to step 8, and in step 8, the same abnormal processing as described above is executed.
If it is determined that the address is within the address 3FFFh, the process proceeds to steps 6 and 7, and in step 7, the stored standby program address (address 1001h) of the task 1 and the registers, flags, stack pointer, and the like are restored. After the end of the runaway detection flow, the process proceeds to the task 1 program shown in FIG. 2A, and the process is performed from the address 1001h as the standby program address. That is, task 1
The processing is executed from the program address next to the program address of the previous end, and the processing can be continued using the register, flag, and stack pointer at the time of the previous end.

Then, such program processing is repeated in the same manner when the next task program is designated.

As described above, in this embodiment, when a task program is designated by the command means 5, the task program being executed is switched to the designated task program by the switching means 6, but at this time, the judgment means According to 8, it is determined whether or not the standby program address is within the program address range of the task program specified before the switching, and if it is determined that the standby program address is not within the range, it is determined that runaway has occurred, and the program is executed. The system is configured to detect runaway by focusing only on the task program that has run out, so that runaway of the task program can be detected in a short time. It is no longer necessary to reduce the execution time of the task program in consideration of the output of a dog pulse. It has become possible to increase the execution time of the click program.

Since runaway is detected by focusing only on the task program that has been executed, there is no need for a program for judging a suspended or stopped task.

Although the invention made by the inventor has been specifically described based on the embodiments, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the gist of the invention. Needless to say, for example, in the above embodiment, the standby program address (the program address to be executed next to the last executed program) is within the range of the program address of the task program designated before switching. Although it is determined whether or not there is a program address, instead of this standby program address, a program address based on the task program executed before switching, for example, the last executed program address or executed A certain program address may be used.

In the above embodiment, the watchdog reset IC 10 is used. However, the signal is sent directly from the judging means 8 to the execution means 9 without using the watchdog reset IC 10 to execute the execution. Means 9
In the above, it is also possible to make the operation at the time of normal / abnormal.

[0033]

As described above, according to the multitask program runaway detection apparatus of the present invention, when a task program is designated by the command means, the task program in execution is designated by the switching means. At this time, the determination means determines whether or not the program address based on the task program executed before the switching is within the program address range of the task program designated before the switching. If it is determined that it is not within the range, it is determined that runaway has occurred, and runaway detection is performed by focusing only on the task program that was being executed. It is possible to extend the execution time of the task program. In addition, since runaway detection is performed by focusing only on the task program that has been executed in this way, a program for judging a suspended or stopped task is of course unnecessary.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an entire configuration of a multitask program runaway detection device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing processing of each task program in association with a program address.

FIG. 3 is a flowchart showing a runaway detection procedure executed according to the present invention.

[Explanation of symbols]

 1-4 Task program storage means 5 Command means 6 Switching means 7 Storage means 8 Judgment means 9 Execution means 20 Multitask program runaway detection device

Claims (2)

(57) [Claims] 1. An apparatus for detecting a runaway of a multitask program in which a program is divided into a plurality of task programs and each of the task programs is executed in a predetermined order. Storage means, switching means for switching the task programs stored in these task program storage means to the designated task program from the command means, and when switching by the switching means , based on the task program executed before the switching . Program address is switched
Determines whether within the scope of the program address of the task program which has been specified before, runaway multitasking program if it is determined not within the range equipped with determining means for determining a runaway, the Detection device. 2. The multi-task program runaway detection device according to claim 1, wherein the storage means for storing at least a program address at the time of switching the task program as a standby program address, and the task executed before the switching by the determination means. When it is determined that the program address based on the program is within the range of the program address of the task program specified before the switching, the program shifts to the standby program address of the task program switched by the switching means and executes the program. A runaway detection device for a multitask program, comprising: an execution unit that executes the program.