JPH08123704A - Controller - Google Patents

Abstract

PURPOSE: To shoreten restoring time by resetting an electronic computer at the time of detecting abnormality in operation to judge the possibility/ impossibility of automatic restoration, and when automatic restoration is possible, setting up the state of a controlled object to a state matched with a restarting condition to restart the object. CONSTITUTION: At the time of inputting a hardware reset signal by a reset mechanism, the hysteresis of abnormal operation generated immediately before abnormal stop is read out from an error hysteresis storing part 20 and whether the abnormality can be automatically restored or not is judged by an automatic restoration judging part 21. A controlled object monitoring processing part 22 monitors the states of respective parts of a process 25 to be a controlled object at the time of the abnormal stop, a starting condition checking processing part 23 checks the restarting conditions of respective parts of the controlled object and an operation output processing part 24 operates respective parts so as to set up them to conditions matched with the restarting conditions instructed by the processing part 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device using a control electronic computer.

[0002]

2. Description of the Related Art In a control device using an electronic computer, an abnormal operation may occur due to a hardware or software defect, a harsh external environment, or the like. If such an abnormal operation occurs, an abnormal operation occurs. Is detected and the history of this abnormal operation is registered, and operation stop processing in the safe direction is performed.

If such a stop occurs, it is necessary to immediately investigate the cause of the abnormality and restore it to a normal state.
Therefore, when the control device stops due to a temporary failure such as contact failure due to noise or vibration among the causes of abnormal operation, it can be remedied simply by retry processing. On the other hand,
When the control program runs out of control and the control function is lost, it is usually monitored by a watchdog timer to detect the program runaway, and if it is not a hardware failure, it is rescued by hardware reset and initialization processing. I often do it.

In the case of performing the latter relief process as described above, depending on the type of the control device, for example, in a continuous control system such as a plant, the current state maintaining operation is in the safe direction, so that the control is automatically performed from a temporary uncontrolled state. It is better to return to the state, but in a system where the control target is line-controlled by multiple computers, it is not possible to stop the entire line when a specific computer stops It is good to disconnect only the computer from the line and restart it automatically to smoothly return to line control.

In a control device for line control by such a plurality of electronic computers, conventionally, a restart control procedure as shown in FIG. 8 has been taken. That is, when a hardware-based reset start is performed, first, a self-diagnosis process is executed according to a software program to check whether there is an abnormality (steps S1 and S2). This self-diagnosis processing is a diagnosis function for confirming abnormality of hardware and software, and performs CPU diagnosis, memory diagnosis, input / output diagnosis, and the like. And if there is no abnormality, working memory, register,
Initialization processing for initializing interrupt vectors, peripheral I / O, etc. is performed, and the original task control is performed (steps S3 and S).
4). However, if there is an abnormality as a result of the self-diagnosis after the reset start, a message indicating the content of the abnormality and the abnormality countermeasure is output, and guidance display processing for stopping the execution is performed (step S6).

In the task control processing of step S4, mutual exclusion, synchronization, communication between execution tasks, etc. are performed in order to coordinately control each execution task that divides the system into several functions, and the entire system is scheduled. ,
Execution processing of each execution task is performed (step S5).

[0007]

However, in such a conventional control device, if a reset start is made after an abnormal stop, each task is restarted by the task control process immediately after the initialization process. Therefore, when restarting the continuous control system or the line control system that has not stopped, the restart cannot be performed smoothly, and there is a risk that the control system may be damaged. That is, if the state of each part of the controlled object is not necessarily a suitable condition for restarting but restarting is applied, for example, the valve that should have been originally open is stopped in a closed state, If the pump is restarted, the flow path piping will be overloaded and it will stop again.

The present invention has been made in view of such conventional problems. When the system abnormally stops, a hardware-like reset start is automatically performed, and then the control computer automatically returns. In addition to the self-diagnosis function of, the software program also has an automatic return function that monitors whether or not the control target status can be restarted and performs the necessary operation to meet the restart condition before restarting. Therefore, it is an object of the present invention to provide a control device that enables smooth restart and shortens the recovery time.

[0009]

According to a first aspect of the present invention, there is provided a control device for monitoring the operation of an electronic computer and outputting an abnormality detection signal when an abnormal operation of the electronic computer is detected. Reset means for outputting a reset command to the electronic computer when the abnormality detection means outputs the abnormality detection signal, and when the reset means outputs the reset instruction, it is determined whether or not the electronic computer can be automatically restored. The automatic recovery determination means and the restart operation means for operating the controlled object of the electronic computer so as to meet the restart condition are provided.

According to a second aspect of the present invention, in the control device according to the first aspect, the control target monitoring means for monitoring the state of the control target at the time of stop, and the state of the control target satisfy the restart condition within a predetermined time. An abnormality display means for displaying an abnormality on the controlled object side when the state is not reached is provided.

According to a third aspect of the present invention, in the control device according to the first aspect, artificial intelligence is used as the restart operation means.

[0012]

In the control device according to the first aspect of the present invention, when the abnormality detecting means detects an abnormal operation of the electronic computer, the reset means resets the electronic computer, and in response to the reset command, the automatic return determining means performs the electronic operation. Determine whether the computer can be automatically restored. Then, if it is determined by the automatic return determination means that the electronic computer can be automatically returned, the restart operation means operates so that the state of the controlled object becomes a state that meets the restart condition, and restarts.

According to another aspect of the control device of the present invention, the controlled object monitoring means monitors the state of the controlled object at the time of stop, and when the state of the controlled object does not meet the restart condition within a predetermined time, Displays the abnormality on the control target side by the abnormality display means.

According to a third aspect of the present invention, in the control device of the first aspect, by using artificial intelligence as the restart operation means, the restart condition accumulated in the restart operation means at the time of a stop due to an abnormal operation of the computer. Restart the controlled object according to the rules.

[0015]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 shows a hardware configuration of a reset mechanism portion of a control computer 1 in a common embodiment of the inventions of claim 1 and claim 2, wherein a CPU 1, a first single shot watchdog timer and a second single shot watchdog timer are shown. (SS W
DT) 2, 3, an external reset signal 4 input from the outside of the system, a hardware reset switch 5 provided in the system, a reset signal (RETOUT) 6 from the CPU 1 and a second single shot watchdog. An OR circuit 8 that ORs the signal 7 from the timer 3, a single shot reset timer (SS RST) 9 that uses the output of this OR circuit 8 as a start signal, and a power-on reset circuit 1 that generates a reset signal when the power is turned on.
0, a single-shot reset timer 9 and a power-on reset circuit 10 are constituted by an OR circuit 11, and the output of this OR circuit 11 gives a hardware reset signal.

FIG. 2 shows timing signals of various parts of the reset circuit. The first single shot watchdog timer 2 in the main program executed by the CPU 1
Trigger pulse (W
DPLS) 12 is generated, and the trigger pulse 12 is input to the single shot watchdog timer 2, whereby the timer 2 is reset and time counting is started. Therefore, when the interval of the trigger pulse 12 is extended, the single shot watchdog timer 2 times up and generates an interrupt signal (NMI) 13 indicating that the CPU 1 has an abnormality and inputs it to the CPU 1.

The interrupt signal 13 is a signal that cannot be interrupt-disabled in the CPU 1, and when the interrupt signal 13 occurs, the CPU 1 performs an abnormal process and stops the execution of the program.

The second single-shot watchdog timer 3 delays the reset signal by the time required for the CPU 1 to execute the abnormal processing when the first single-shot watchdog timer 2 outputs the interrupt signal 13. The delay time t2 is secured, and the watchdog timer signal (WDTD) 7 is output to the OR circuit 8.

When the interrupt signal 13 is input from the first single shot watchdog timer 2, the CPU 1 carries out an abnormal process and ORs the reset signal (RETOUT) 6.
Output to the circuit 8.

The OR circuit 8 receives the external reset signal 4, the reset signal from the reset switch 5, the reset signal 6 from the CPU 1 or the watchdog timer signal 7 of the second single-shot watchdog timer 3 as input. , The single-shot reset timer 9 is started, and the reset signal (RST) 14 having the pulse width t3 is input to the final stage OR circuit 11.

This OR circuit 11 takes the logical sum of the reset signal from the power-on reset circuit 10 and the reset signal 14 from the single shot timer 9 when the power is turned on,
It outputs a hardware reset signal when either signal is input.

The above is the hardware configuration of the reset mechanism of the control electronic computer. The electronic computer also has an automatic restart processing mechanism as shown in FIG. 3 as a software program. Execute the startup process to restart the control target. This automatic restart processing mechanism includes an error history storage unit 20 that stores a history of abnormal operations of the electronic computer, and a hardware reset signal input by the reset mechanism described above.
The history of the abnormal operation immediately before the abnormal stop of the error history storage unit 20 is read, and the state of the automatic recovery determination unit 21 that determines whether the abnormality can be recovered automatically and the state of each part of the process 25 that is the control target at the time of the stop are shown. A control target monitor processing unit 22 for monitoring, a start condition check processing unit 23 for checking restart conditions of each control target unit, and a state where each control target unit meets the restart condition instructed by the start condition check processing unit 23. And an operation output processing unit 24 that operates so that

The automatic restart processing mechanism configured as described above operates based on the flow chart shown in FIG. 4 when there is a stop due to an abnormal operation of the electronic computer. That is, when a hardware reset signal is output by the reset mechanism shown in FIG. 1 after the electronic computer has stopped due to an abnormal operation, this hardware reset signal is output to the automatic recovery determination unit 2
1 is input, the automatic recovery determination unit 21 first executes a self-diagnosis process for confirming the abnormality of the hardware and software of the electronic computer itself (step S21). In this self-diagnosis processing, CPU diagnosis, memory diagnosis, input / output diagnosis, etc. are performed.

In the self-diagnosis processing, it is checked whether there is any abnormality such as hardware abnormality, loss of program or data memory, and if there is abnormality, automatic restart is impossible. Therefore, guidance of abnormality of electronic computer is displayed (step S34). ), If no abnormality is found, the process proceeds to the next initialization process (step S23). In this initialization process, the working memory,
Initialize registers, interrupt vectors, peripheral I / O, etc.

Subsequently, an error history check process is performed to check the cause when the abnormality of the electronic computer occurs, and to judge whether or not the automatic recovery is possible (steps S24 and S2).
5). The error history table 15 is illustrated in FIG. 5, but this table 15 is information about abnormal operations that are sequentially stored in the error history storage unit 20. As information about recent abnormal operations, “June 2, 1994” is shown. At 14:10:34 on the day, there was no I / O response three times on the 03 board. " And before that, it can be seen that an abnormality "memory parity occurred at 12:00" occurred.

Therefore, when the computer stops due to an abnormal operation, the automatic recovery judgment unit 21 searches the error history table 15 of the error history storage unit 20 to find the abnormality that has occurred immediately before, and the abnormality is detected. If it is a transient one and the same abnormality does not occur again when it is restarted, it is determined that automatic recovery is possible, and the process proceeds to the control target monitor process of the next step S26, but the abnormality is permanent. If it is determined that the restart is inappropriate, a guidance to that effect is displayed (step S35).

In the next step S26, the controlled object monitor processing section 22 monitors the state of each section of the process 25 which is in an uncontrolled state because the computer has stopped due to the occurrence of an abnormality. For example, power supply status, valve open / close status, pump status, temperature, pressure, flow rate, and other sensor inputs / outputs required for control, and the operating status of the equipment of each part are monitored.

Then, the activation condition check processing unit 23 executes the activation condition check processing (step S27). In this start condition check process, whether or not a failure is caused even when restarting from the uncontrolled state, the control target monitor process result is set as the restart condition of each part of the process 25 registered in the start condition check processing part 23. When the collation is performed and a state where the restart condition is not satisfied is found, the information is passed to the operation output processing unit 24.

The operation output processing unit 24 looks at the check result passed from the start condition check processing unit 23, outputs an operation command to a necessary portion of the process 25, and changes the state of each unit so as to meet the restart condition. Operate (Step S2
8). When this operation output process is started, a timer (not shown) is started, and it is determined whether the start condition check and the necessary operation output process are completed within a predetermined time, and if it becomes a restartable state, it is restarted. It is activated (steps S29 and S3).
0). However, if the restart process is not completed within the predetermined time, and therefore the timer expires in step S29, it is determined that there is an abnormality on the process 25 side, and a guidance is displayed regarding the abnormality on the process side (step S36).

At the time of restart, the computer performs mutual exclusion, synchronization, communication between execution tasks, etc. in order to coordinately control each execution task that divides the system into several functions, and schedules the entire system. Control processing is performed (step S31), and thereafter, execution processing of each execution task is performed (step S32).

As described above, in the control device of this embodiment, the control computer stops due to an abnormal operation,
When the controlled object goes into the uncontrolled state, the computer automatically resets the hardware, and the software program determines the possibility of automatic recovery. It monitors the status of each part of the controlled object that is placed, operates so as to meet the restart condition, and if the restart condition can be set within a predetermined time, it automatically restarts, so quickly and accurately. The system can be restarted and the recovery time can be shortened.

FIG. 6 shows a functional block diagram of an embodiment of the present invention as defined in claim 3. The characteristic feature of this embodiment lies in the artificial intelligence processing unit 26, and the other components are shown in FIGS. The second embodiment is common to the first embodiment shown, and the same reference numerals are given and detailed description thereof will be omitted.

In the control device of the second embodiment, the control target monitor processing unit 22, the starting condition check processing unit 23, and the operation output processing unit 24 of the first embodiment shown in FIG. When the judgment command of the automatic return possibility on the computer side is given, the sensor signal and the status signal of each part of the process 25 to be controlled are read, and, for example, these signals are used as the antecedent part. −
Based on the THEN rule, the operation output required for restart is derived, and the operation of each part of the process 25 is performed within a predetermined time.

The restart process by the control device of this embodiment follows the flowchart shown in FIG. That is, the processing from the reset start in steps S21 to S25 to the automatic return determination on the electronic computer side is the same as the flowchart of the first embodiment shown in FIG. 4, but the processing after it is determined that automatic return is possible Has been changed to artificial intelligence processing (step S40). In the artificial intelligence processing of step S40, the sensor signal, the status signal, the switch signal, and the like of each part of the process 25 are received, the antecedent part of the IF-THEN rule is illuminated, and the consequent part of the corresponding rule is required. The operation output is derived, and the operation output is given to the corresponding part of the process 25. Then, the restart operation output process by the artificial intelligence process is completed within a predetermined time managed by the timer (steps S41 and S42). If it is not completed within a predetermined time, a guidance is displayed that restarting is impossible (steps S41 and S45).

If a smooth restart is possible, as in the first embodiment, the electronic computer performs mutual exclusion, synchronization, and execution in order to coordinately control each execution task that divides the system into several functions. Inter-task communication is performed to perform task control processing for scheduling the entire system (step S43), and thereafter, execution processing of each execution task is performed (step S44).

As described above, in the control device of the second embodiment, the restart condition is adjusted by the artificial intelligence processing so that the restart is automatically performed, so that the accumulation of knowledge rules is increased. It becomes possible to perform more accurate restart processing.

[0037]

As described above, according to the invention of claim 1,
When the abnormality detection means detects an abnormal operation of the electronic computer, the reset means resets the electronic computer, and in response to this reset command, the automatic return determination means determines whether the automatic return of the electronic computer is possible or not. If it is determined by the return determination means that the computer can be automatically returned, the restart operation means operates so that the state of the controlled object meets the restart condition and restarts. Each part can be operated to meet the restart condition for the control target that has become uncontrolled due to the stop of the electronic computer, and it can be restarted automatically, and the restart process can be performed quickly and accurately. Recovery time can be shortened.

According to the second aspect of the present invention, the state of the controlled object at the time of stop is monitored by the controlled object monitoring means, and when the state of the controlled object does not meet the restart condition within a predetermined time, an abnormality occurs. Since the display means displays the abnormality on the controlled object side, if there is an abnormality on the controlled object side when restarting is not possible, it can be known by the display, and the part where the abnormality has occurred can be easily recognized. It is possible to deal with it easily.

According to the invention of claim 3, in the control device of claim 1, since the artificial intelligence is used for the restart operation means, when the computer is stopped due to an abnormal operation, it is stored in the restart operation means. It is possible to perform the restart operation of the control target according to the restart condition rule, and it is possible to perform the restart processing quickly and accurately and reduce the recovery time.

[Brief description of drawings]

FIG. 1 is a circuit block diagram of a reset mechanism portion of a common embodiment of the inventions of claims 1 and 2. FIG.

FIG. 2 is a signal waveform diagram of each part of the reset mechanism portion of the above embodiment.

FIG. 3 is a functional block diagram of a restart processing mechanism portion of the above embodiment.

FIG. 4 is a flowchart of an automatic restart process of the above embodiment.

FIG. 5 is a memory structure diagram of an error history table of the above embodiment.

FIG. 6 is a functional block diagram of a restart processing mechanism portion according to an embodiment of the invention of claim 3;

FIG. 7 is a flowchart of an automatic restart process of the above embodiment.

FIG. 8 is a flowchart of a restart process of a conventional example.

[Explanation of symbols]

 1 CPU 2 Single Shot Watchdog Timer 3 Single Shot Watchdog Timer 5 Reset Switch 8 OR Circuit 9 Reset Timer 11 OR Circuit 20 Error History Saving Section 21 Automatic Recovery Judgment Section 22 Control Target Monitor Processing Section 23 Startup Condition Check Processing Section 24 Operation Output processing unit 25 Process 26 Artificial intelligence processing unit

Claims (3)

[Claims] 1. An abnormality detecting unit that monitors an operation of an electronic computer and outputs an abnormality detection signal when an operation abnormality of the electronic computer is detected; and an abnormality detecting unit that outputs the abnormality detection signal when the abnormality detecting unit outputs the abnormality detection signal. Reset means for outputting a reset command to the electronic computer, when the reset means outputs the reset command,
A control device comprising: an automatic return determination means for determining whether or not the electronic computer can be automatically returned, and a restart operation means for operating a state of a control target of the electronic computer so as to meet a restart condition. 2. A controlled object monitoring means for monitoring the state of the controlled object at the time of stop, and when the state of the controlled object does not meet a restart condition within a predetermined time,
The control device according to claim 1, further comprising an abnormality display unit that displays an abnormality on the control target side. 3. The control device according to claim 1, wherein artificial intelligence is used for the restart operation means.