JPH09179751A - Self-diagnostic system for controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of miscontrol by enhancing a self-diagnostic function to be integrated in a controller by a self-diagnostic function added to the external without depending only upon a microprocessor for managing control. SOLUTION: The controller consisting of a power on reset function 103, an operator reset receiving circuit 104, a microprocessor 101, a control program storing memory 102, an abnormality informing function 120, and control functions 110 to 112 for controlling a control target is also provided with a self-diagnostic sequence circuit 130 and a microprocessor diagnosis judging circuit 140. The circuit 130 scans a result signal 140a from the circuit 140 after the lapse of a fixed time after releasing the reset of the microprocessor 101, and at the time of detecting abnormality, the circuit 130 asserts an abnormality informing signal 130d, and then stops the operation of the microprocessor in a state of outputting a reset signal 130a as it is to prevent the generation of miscontrol. When the microprocessor is normal, the circuit 130 asserts the reset signals 130a, 130b in a state of negating the abnormality informing signal 130d as it is.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-diagnosis method for a control device or the like which uses a microprocessor for performing a self-diagnosis by artificially operating each function in the control device or system prior to actual control. is there.

[0002]

2. Description of the Related Art In a control device or system using a microprocessor, power is applied to the device to start control processing, or an initialization command (reset) is issued to restart control processing. In this case, it has become common to perform self-diagnosis processing before actual control processing is executed.

This is because the microprocessor controlling the device operates each function in the device in a pseudo manner prior to the actual control processing, analyzes the operation result, and the function operates correctly. It is to determine whether or not there is.

The purpose of this self-diagnosis process is to raise the safety by notifying the operator when an abnormality is recognized and not executing the actual control process of the apparatus.

FIG. 12 is a conceptual diagram showing the configuration of these general control devices in an easy-to-understand manner. In the figure, 10
Reference numeral 0 is the entire general control device, and 101 is a microprocessor that controls the control. 102 is the microprocessor 1
01 is a memory for storing a control program that stores a program to be executed by ROM 01, a ROM (Read Only Memory) or RA
It is composed of M (Random Access Memory).
103 is a power-on reset function circuit for monitoring the power supply and generating a reset signal to the microprocessor when the power supply rises. 104 is an operator set for receiving a reset operation by the operator and other external reset conditions. Reception circuit, 105 is circuit 103 and 1
This is an or circuit for obtaining the reset or condition of 04.

Further, 110, 111, 112, ... Show control functions for actually controlling individual controlled objects, and 200, 201, 202 ,. Shows the target.

Reference numeral 120 denotes an abnormality notifying function circuit for notifying the outside when an abnormality is detected as a result of self-diagnosis. Here, the microprocessor 101 that has detected the abnormality notifies the outside of the abnormality using this function.
Reference numeral 120a is an abnormality notification signal for an external device or the like.

Reference numeral 101a denotes an address bus that collects address signals provided by the microprocessor 101 to the control program storage memory 102, and reference numeral 102a denotes data for the microprocessor to read the program data stored in the control program storage memory.・ Bus, 1
01b is a control bus for the microprocessor to operate the control function.

103a is the power output from the circuit 103
ON / reset signal, 104a is a reset signal output from the circuit 104 by processing of an operator, etc.
a is a reset signal output by the or circuit 105 and given to the microprocessor.

Next, FIG. 13 is a conceptual diagram for explaining the contents of the control function block in FIG. 12 in a little detail, focusing only on the control function 110. In the figure, 101, 110 and 200 are the same as those in FIG. 1
Reference numeral 101 is a command register for the microprocessor 101 to write an operation command to the control function to instruct the operation, 1102 is an actual processing function block for actually executing control of the control target, and 1103 is an actual processing function. It is a result display register for the microprocessor to read the execution result of.

In the control device as shown in FIGS. 12 and 13, when the power is turned on, the power is turned on.
When the reset circuit 103 asserts the power-on reset signal of 103a or the 104a signal which is the output of the circuit 104 is asserted by the processing of the operator or the like, the reset signal of the microprocessor is sent via the or circuit 105. Signal 105a is asserted.

This signal is negated after a certain period of time, whereby the microprocessor 101 starts fetching and executing an instruction from a predetermined position (address) of the control program storage memory 102. By arranging a program for self-diagnosis in the program of this execution start portion, execution of self-diagnosis processing immediately after startup is realized.

In the control device shown in FIG. 12, when the device starts up, the microprocessor 101 operates the control function block according to the self-diagnosis program, and determines whether or not the target control function is operating as it is.

For example, when diagnosing the control function 110, the microprocessor 101 writes a processing command for self-diagnosis in the command register 1101 shown in FIG. 13, and the processing for diagnosis in the actual processing function block 1102. Give orders. The actual processing function block 1102 performs a pseudo control operation according to an instruction from the microprocessor, and displays the result in the result display register 1103.

The microprocessor 101 reads the content of the result displayed in the result display register 1103, and if it matches the expected value, the function of this control function block is considered to be operating normally. You

The same processing is performed by the control functions 111, 112,
When it is determined that all are normal, the microprocessor 101 determines that the self-diagnosis result is good, and shifts to actual control processing.

On the other hand, when the microprocessor 101 reads the content of the result displayed in the result display register 1103, and this does not match the expected value, the function of this control function block becomes normal. The operator is considered to be unable to operate, and a warning is issued to the operator to notify him / her of the abnormal content. In this case, the actual control processing thereafter is not performed, and the microprocessor 101 stops its operation by executing a halt instruction or the like.

[0018]

In order to realize the above self-diagnosis function, the microprocessor must operate normally, that is, "the microprocessor and the control program storage memory peripheral circuit in the device are both "It works properly" is a major premise.

In other words, "if any of the microprocessor and the control program storing memory peripheral circuit in the apparatus does not operate normally, the self-diagnosis function itself cannot be realized".

In the operation of the control device, the self-diagnosis function is a very important function for improving the reliability of the device and ensuring safe operation. Also, considering the manufacture of a control device using a microprocessor, inspection of this control device,
The self-diagnosis function is an indispensable function in diagnosing each function of this device in the test stage.

However, in the product after the end of manufacturing, the failure of parts and the trouble in manufacturing occur with a certain probability, and the defect is "microprocessor or control program storing memory peripheral circuit". It is not uncommon to reach.

It is also conceivable that a part may fail during transportation before delivery of the device or in an operation stopped state until the power is turned on.

When a failure occurs in the "microprocessor or the control program storing memory peripheral circuit" in this way, the microprocessor is
Not only can self-diagnosis processing not be executed, but there is also the danger that it will not operate at all or run out of control, causing a fatal accident.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a self-diagnosis function incorporated in a control device to an external self-diagnosis function without relying only on a microprocessor. If it is determined that a defect has occurred in the microprocessor or control program storage memory peripheral circuit by enhancing it with diagnostic hardware, stop the operation of the microprocessor, notify the outside to the abnormality, and control An object of the present invention is to provide a self-diagnosis method and mechanism of a control device capable of preventing erroneous control of an object.

[0025]

A self-diagnosis method for a control device according to the present invention comprises a microprocessor for controlling the control and a memory for storing a control program. Each function in the device is controlled before actual control processing is executed. In a self-diagnosis method of a control device or system for self-diagnosis, a microprocessor diagnostic program for diagnosing the function of the microprocessor itself is stored in a specific area of the control program storage memory, and the entire microprocessor self-diagnosis mechanism is The self-diagnosis sequence circuit and the microprocessor diagnosis result judgment circuit for the microprocessor to write the execution result of the microprocessor diagnosis program and judge the result. Or by power-on reset Although the reset signal for the microprocessor is directly applied to the microprocessor, it is taken into this circuit, and a part of the address to the memory for storing the control program generated by the microprocessor is taken in by the self-diagnosis sequence circuit and passed through this circuit. Generates an address to be given to the control program storage memory,
At the time of power-on reset, the self-diagnosis sequence circuit resets the microprocessor once, and at the same time, gives the address of the preset microprocessor diagnostic program to the control program storage memory, and Releasing the reset causes the microprocessor to execute the microprocessor diagnostic routine. In this microprocessor diagnostic routine, the microprocessor is instructed to write the operation result to the microprocessor diagnostic result determination circuit. The judgment circuit stores the correct data obtained during normal execution in advance as an expected value, and compares it with the result data written by the microprocessor diagnosis to judge whether the judgment result is normal or abnormal. After a fixed time, the self-diagnosis sequence circuit scans the judgment result of this microprocessor diagnosis result judgment circuit, and if it is normal, resets the microprocessor again and then stores the control program. After switching the address given to the memory to the address output by the microprocessor, the reset is released and the control right of the device is handed over to the microprocessor.If an abnormality is detected, the abnormality is notified to the outside and By keeping the processor reset, the malfunction and control of the device are prevented.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. 1 shows the configuration of a control device equipped with a self-diagnosis function. In the figure, the same components as those shown in FIG. 12 of the related art are designated by the same reference numerals and their duplicate description will be omitted.

In FIG. 1, 130 and 140 are parts added by the present invention, 130 is a self-diagnosis sequence circuit, and 140 is a microprocessor diagnosis judgment circuit.
130a is a reset signal to be given to the microprocessor 101 from the self-diagnosis sequence circuit 130;
b is a reset signal for the microprocessor diagnosis determination circuit 140 from the circuit 130, 101a 'is a partial address line of the address bus 101a given from the microprocessor 101 to the control program storing memory 102, 1
01a "is the remaining address bus line of the address bus 101a except 101a ', and 130c is the address 10
1a "is an address bus line for supplying a part of the address bus to the control program memory 102 after replacement, 130d is an abnormality detection signal from the circuit 130 to the abnormality notification function circuit 120, and 140a is a microprocessor. This is a determination result signal of the diagnostic determination circuit 140.

Next, the operation of the self-diagnosis method according to the present invention will be described with reference to FIG.

First, when the power is turned on, the signal 103a of the power-on reset function circuit 103 is asserted,
The 105a signal is generated. On the other hand, the signal 105a is generated by asserting the signal 104a from the operator / reset acceptance circuit 104 by a reset operation by the operator or a reset command from the outside.
This signal is a complete reset request for the device and will be negated after a period of time. In the conventional control device of FIG. 12,
Although this was directly given to the microprocessor 101, in the present apparatus, this is the self-diagnosis sequence circuit 13
Give to 0.

The self-diagnosis sequence circuit 130
Reset signal 130a to the microprocessor 101
Then, the reset 130b of the microprocessor diagnosis determination circuit 140 is asserted for a certain period of time. When the microprocessor 101 can operate normally, the microprocessor 101 sends a fixed address defined by the trap by the reset to the bus 101a (10
1a ′ and 101a ″ are output to the combined bus).

Here, the self-diagnosis sequence circuit 130
Outputs specific address information to the address bus line 130c regardless of the input state of the address bus line 101a ".

With this function, an address different from the address output by the microprocessor 101 is given to the control program storage memory 102.

Here, this different address (signal 13
A dedicated program (microprocessor diagnostic routine) for diagnosing the microprocessor 101 itself will be described in the memory area specified by 0c). This microprocessor diagnostic routine includes a process of storing a specific value obtained by executing a large number of instructions of the microprocessor itself in a result register in the microprocessor diagnostic determination circuit 140.

As a result, when the microprocessor 101 and the control program storage memory 102 are operating normally, after a certain period of time, the microprocessor diagnostic routine is actually run under the control of the microprocessor. The expected calculation result is given to the microprocessor diagnosis determination circuit 140.

Microprocessor diagnostic determination circuit 140
Is a circuit including a result register for the microprocessor to write the operation result data for determination and a comparator for comparing the result data with an expected accurate value. The reset signal 130b is used to clear the contents of the result register of the microprocessor diagnostic judgment circuit 140. Therefore, immediately after receiving the reset, the output signal 140a of the comparator of this determination circuit shows a mismatch (abnormal) state. This indicates a coincident (normal) state when a value equal to the expected value is written as a result of the diagnostic operation of the microprocessor.

The self-diagnosis sequence circuit 130 releases the reset to the microprocessor 101, and then
Microprocessor diagnostic judgment result signal 14 after a fixed time
0a is scanned, and if an abnormality is detected, the abnormality notification signal 130d is asserted to notify the occurrence of the abnormality to the outside, and then the microprocessor reset signal 13
The operation of the microprocessor is stopped while 0a is output.

On the other hand, if the scan of the signal 140a is found to be normal, it is determined that the microprocessor 101 is operating normally. In this case, the abnormality notification signal 130a remains negated and the reset signals 130a and 130b are asserted again.

When the reset signal is output for a certain period of time and then this signal is negated, the microprocessor 101 enters the restart state, and the certain address defined by the trap due to the reset is given to the bus 101a (101a 'and 101a).
a) to the combined bus).

After this phase, the self-diagnosis sequence circuit 130 outputs the input address 101a "as it is to the address bus 130c. That is, the address output by the microprocessor 101 is given to the control program storing memory 102 as it is. It will be.

This completes the operation of the self-diagnosis sequence circuit 130, and the microprocessor 101 starts executing the original self-diagnosis processing stored in the control program storage memory 102 and the actual control processing. To do.

In this way, the self-diagnosis sequence circuit 13
By adding 0 and the microprocessor diagnostic determination circuit 140 and using them, the failure or defect included in the “microprocessor or control program storing memory peripheral circuit” can be eliminated.
It is possible to prevent the erroneous control by detecting and stopping the device prior to the actual control operation.

FIG. 2 shows a concrete configuration example of the self-diagnosis sequence circuit 130 in FIG. In FIG.
0 is the whole self-diagnosis sequence circuit, 150 is a clock generation circuit, 1301 is a sequence circuit, 1302 is a microprocessor diagnosis program / address storage circuit, 1
Reference numeral 303 is a multiplexer circuit.

Further, 150a is a clock signal, 1301
Reference numeral a is an address selection signal for selecting which input signal the multiplexer circuit 1303 outputs.

101a ", 105a, 130a, 130
The signals b, 130c, 130d and 140a are the same as in FIG. (105a is a reset input signal, 130a
Is a microprocessor reset signal, 130b is a microprocessor diagnosis determination circuit reset signal, 130d is an abnormal communication signal, 140a is a microprocessor diagnosis determination result signal, 101a ″ is a part of the microprocessor output address, and 130c is a control program storage signal. (This is a part of the address to be given to the memory.) In such a hardware configuration, the clock circuit 150 can be realized by a crystal oscillator, etc. Further, the sequencer circuit 1301.
Can be easily realized by a PLD (Programmable Logic Device) device or the like. The microprocessor diagnostic program / address storage circuit 1302 and the multiplexer circuit 1303 can also be stored in the PLD, but here they are represented by general circuits for the sake of easy understanding. Circuit 1302 is DIP
It may be a setting circuit such as a switch or a fixed data output circuit such as a PROM. The multiplexer circuit 1303 can be composed of a commercially available logic IC.

FIG. 3 shows a concrete example of the configuration of the microprocessor diagnosis / determination circuit 140 shown in FIG. In the figure, 140 is the entire microprocessor diagnostic determination circuit,
Reference numeral 1401 is a microprocessor diagnostic result register writable by the processor, 1402 is a diagnostic result expected value storage circuit, and 1403 is a comparator circuit.

Further, 101b is a control bus of the microprocessor, 130b is a reset input signal of the circuit 140, 1
40a is a microprocessor diagnosis determination result output signal. Further, 1401a is an output signal bundle of data stored in the microprocessor diagnosis result register 1401.
42a is an output signal bundle of data stored in the diagnostic result expected value storage circuit 1402.

In order to realize the self-diagnosis operation of the method of the present invention in such a hardware circuit, it is necessary to realize the sequencer circuit 1301 of FIG. 2, but here, a simple sequencer is realized by using the PLD. An example will be described.

FIG. 4 is a state transition diagram of the sequencer by this PLD. The conversion of the PLD program from this transition diagram can be easily performed by a known software technique.

Here, two timer elements, timer 1 for counting the time required for the diagnostic processing of the microprocessor and timer 2 for counting the time required for the reset of the microprocessor, are defined in the PLD sequencer. . Clock signal 150a is the base clock for this sequencer transition.

These two timers may be composed of an IC such as a mono-multivibrator outside the PLD, or P
It may be configured in the LD.

The operation of the self-diagnosis sequence circuit 130 will be described with reference to the transition diagram of FIG.

<Phase 1> First, the reset signal 105
This circuit returns to the initial state by asserting a. (1) Signal 103a (microprocessor reset)
Assertion of (2) signal 103b (reset of microprocessor diagnostic judgment circuit) (3) output of signal 103d (abnormality notification signal) normal level (4) A (already set value) of signal 1301a (memory address selection signal) Selection level output As a result, the microprocessor 101 and the microprocessor diagnosis determination circuit 140 are reset, and the abnormality notification circuit outputs a normal value.

Further, according to (4), since the multiplexer circuit 1303 outputs the data on the side of the microprocessor diagnostic program / address storage circuit 1302 to the bus 130c, the area of the address given to the control program storage memory is the microprocessor. It will point to a diagnostic routine.

<Phase 2> When the signal 105a is negated and the reset is released, (1) the signal 103a (microprocessor reset)
(2) Negation of signal 103b (reset of microprocessor diagnostic judgment circuit) (3) The timer 1 is started.

As a result, the microprocessor 101
Starts the operation, and the control program storage memory 102
The microprocessor diagnostic routine is read from and the execution is started. In this processing, the instruction execution of the microprocessor is executed once, and the basic operation can be confirmed. If it is normal, a correct value is written to the microprocessor diagnosis result register 1401 after a fixed time.

In the diagnostic result expected value storage circuit 1402, a correct result value calculated by normal operation of the microprocessor 101 is preset, and in the initial state, the microprocessor diagnostic result register 1401 is cleared. Therefore, the comparator 1403 outputs an abnormal level to the determination signal 140a indicating the abnormal direction.

When the microprocessor 101 executes the microprocessor diagnosing routine and stores the result in the result register 1401, if the content matches the value of the diagnostic result expected value storage circuit 1402, the judgment signal becomes the normal level, If they do not match, the level is abnormal.

<Phase 3> When the timer 1 has timed up after a time with a further allowance has passed from the time estimated that the microprocessor diagnostic routine will end, (1) signal 140a (microprocessor diagnostic result determination signal) Scan.

<Phase 4> Signal 1 in Phase 3
If an abnormal level is detected by scanning 40a (microprocessor diagnostic result determination signal),
In this phase, (1) signal 103d (abnormality notification signal) abnormal level output (2) signal 103a (microprocessor reset)
Is asserted.

As a result, the fact that an abnormality has occurred in the self-diagnosis of this device is notified to the outside, and the microprocessor resets in order to avoid the risk of continuing further operation and performing erroneous control. Stop in a closed state.

The diagnostic process at the time of abnormality determination is completed, and there is no transition from this phase until the signal 105a is asserted again.

<Phase 5> Signal 1 in Phase 3
If it is determined to be normal by the scanning of 40a (microprocessor diagnosis result determination signal), this phase is entered. (1) Signal 103a (microprocessor reset)
(2) B (microprocessor output value control) selection level output of signal 1031a (memory address selection signal) (3) Timer 2 is started.

As a result, the microprocessor 101 is reset again, and the multiplexer circuit 1303 outputs the data on the output address side of the microprocessor of the bus 101a "to the bus 130c according to (2). The area of the address given to is the address itself generated by the microprocessor and points to the regular program.

<Phase 6> When the time required for resetting the microprocessor elapses and the timer 2 times out, (1) signal 103a (microprocessor reset)
Is negated and the microprocessor starts operating.

The diagnostic process at the time of normality determination is completed, and no transition is made from this phase until the signal 105a is asserted again. As a result, the abnormality notification circuit for the outside indicates normality, and the signal 1301a (memory address selection signal) is continuously executed with the microprocessor output value side of B selected.

By realizing such a can with general hardware and PLD, it is possible to realize the self-diagnosis function of the microprocessor itself according to the present invention.

Embodiment 2 The example of FIGS. 1 to 4 can be further developed to bring it closer to practical use. For example, in the case of a general control unit equipped with a microprocessor, the reset state at power-on (called a power-on reset or cold reset) executes self-diagnosis, but it does not occur during normal execution. In the case of resets (called warm resets or hot resets), it is common to omit this time-consuming self-test.

Further, although it is a kind of warm reset, a reset that is executed by a microprocessor based on software based on its own judgment (software reset)
However, in this case as well, it is desirable that the self-diagnosis processing can be omitted.

However, in the case of FIGS. 1 to 4, only one reset is input to the sequencer, and when the signal 105a is asserted, this self-diagnosis processing is uniquely executed.

Therefore, it is possible to realize a more practical self-diagnosis circuit by increasing the conditions input to this sequencer circuit.

FIG. 5 shows the configuration of a control device equipped with a self-diagnosis function that can determine whether or not to execute this self-diagnosis sequence for each type of reset conditions.

In the figure, 160 is a software reset generation circuit operated by the microprocessor 101, and 160a is a software reset signal. Further, the reset signal or circuit 105 in FIG.
And the meaning of the signals 103a and 105a are changed. Other blocks and signal lines are the same as in FIG. In this case, the self-diagnosis sequence circuit 130 is as shown in FIG.

In FIG. 5, the software reset generation circuit 160, when operated by the microprocessor 101, asserts the software reset signal 160a for a certain period.

The input signal 105a is the software reset signal 160a and the reset signal 1 by the operator.
Since it is the OR condition signal of 04a, it indicates a warm reset, and the input signal 103a indicates a power-on reset.

As a result, the power-on reset and the warm reset can be discriminated, and the self-diagnosis sequencer circuit can be realized by using this as the input condition of the sequencer.

FIG. 7 shows an example of the state transition (program) of the sequence circuit 130 in the circuit configuration of FIG.

In FIG. 7, the newly added sequence is a transition condition from phase 7 to phase 4 to phase 1.

In phase 7, the signal 105 in phase 6 is used.
Transition occurs when a is asserted, (1) signal 130a (microprocessor reset)
Is asserted, and if the signal 105a is negated, the process returns to phase 6.

As a result, in the warm reset after the device has normally started up, the self-diagnosis routine of the microprocessor can be omitted. (power·
Only when the on-reset signal 103a is asserted, the phase 1 is entered and the microprocessor self-diagnosis is restarted. ) In phase 4 state, signal 103a or signal 105a
Transitions to phase 1 only when is asserted.

Embodiment 3 FIG. 8 shows the configuration of a control device equipped with a self-diagnosis function which further enhances the microprocessor self-diagnosis function and is capable of discriminating the contents of an abnormality to a more detailed level.
FIG. 9 shows a circuit configuration of the microprocessor diagnostic sequence circuit 130 in FIG.

In FIG. 8, 170 is an error code display function for displaying to the operator the contents (code) when there is an abnormality as a result of microprocessor diagnosis, and 130e is a function for writing this abnormality display code. It is an error code data signal bundle.

In FIG. 9, reference numeral 1302 denotes a microprocessor diagnostic program / address storage circuit, which is realized by a memory so that a plurality of address information can be stored.

Reference numeral 1301b denotes a microprocessor diagnostic program / address selection signal bundle for indicating which address of the address information is selected from the sequencer circuit 1301. Other blocks and signal lines are the same as those in FIGS. 1 and 2.

Next, FIG. 10 shows an embodiment of the microprocessor diagnostic judgment circuit in this case. In FIG.
01, 1402, 1403 blocks, 101b,
The signals 130b, 140a, 1401a, 1402a are the same as those in FIG. 3, but the diagnostic result expected value storage circuit 1
402 is realized by a memory so that a plurality of expected values can be stored, and a plurality of microprocessor diagnostic routines can be stored.
Prepare different expected expected values for each result in advance.

The circuit 1042 also includes a microprocessor diagnostic program / address selection signal bus 1301b.
Is input so that the corresponding expected value of the correct result is selected for each selected and executed microprocessor diagnostic routine.

FIG. 11 shows the state transition of the sequencer circuit 1301 in this case. Here, for simplification, the case where the microprocessor diagnostic program is divided into two steps (steps 1 and 2) and executed is shown.

Phases 1, 3 and 5 are equivalent to those shown in FIG.

The phase 2 corresponds to the phase 2 of FIG. 4, but the processing for outputting the address value for selecting the step 1 is added to the microprocessor diagnostic program / address selection signal bundle 1301b.

The phase 4 corresponds to the phase 4 in FIG. 4, but the processing for displaying the error code of step 1 (here, temporarily "1") is added to the error code data signal bundle 130e. Has been done.

The phase 6 is the same as the phase 2, but the address value selected by the microprocessor diagnostic program / address selection signal bundle 130b is the step 2.

Phase 7 is equivalent to phase 3, and phase 9 is equivalent to phase 5.

Phase 8 is equivalent to phase 4, but the error code displayed in the error code data signal bundle 130e indicates step 2. (here,
Temporarily set to "2") Phase 10 is equivalent to phase 6 of FIG.

As shown here, the sequencer circuit 130
While sequentially changing the state of the microprocessor diagnosis program / address selection signal bundle 1301b output from 1, the processor executes different microprocessor diagnosis routines and writes the diagnosis result in the result register 1401 of the microprocessor diagnosis determination circuit 140. .
At the same time, the signal 1301b becomes the comparison value selection signal 1402 of the microprocessor diagnostic result judging circuit 140, and is compared with the expected value corresponding to the diagnostic processing. The result is judged by comparing the value written in the result register with the expected value.

A unique code is assigned to each microprocessor diagnostic routine, and when an abnormality is recognized, the sequencer outputs the code corresponding to the diagnostic content in which the abnormality has occurred to the error code data signal bundle 10
After writing to the error code display circuit 170 through 3e, the microprocessor is stopped in the reset state.

This error code display allows the operator to know in which part of the microprocessor diagnostic process the abnormality was detected.

The present invention can be similarly applied to a control system using a microprocessor.

[0097]

Since the present invention is configured as described above, the following effects can be obtained.

(1) In a control device using a microprocessor, immediately after the power is turned on, the control by the microprocessor is not started immediately, but the self-diagnosis sequencer is activated to store the microprocessor itself and the control program. Diagnose the area around the memory, judge the result of this pointer stage, and if it is normal, pass control to the microprocessor, and if not, notify the abnormality to the outside and the control circuit after the microprocessor is in the reset state. It means that the microprocessor itself, which is the brain of the control device, is diagnosed, and not only simply increases the reliability of the self-diagnosis function by conventional software and expands the diagnosable range,
Since the most core hardware is diagnosed, it is possible to significantly improve the reliability of the entire device.

(2) As a result, the control device may run out of control at the time of power-on due to a defect or failure around the microprocessor or cause a fatal accident by erroneous control while high reliability is required. This can be prevented in advance.

(3) It is useful for the above-mentioned defect extraction in the manufacturing inspection and test process, and the functional test around the microprocessor can be performed when the power of the apparatus is turned on.

(4) In particular, if a more precise self-diagnosis sequence circuit is prepared, it is possible to determine which part of the microprocessor and control program storing memory peripheral circuit has any defect. Become.
As a result, it is possible to greatly improve the efficiency of the inspection and test processes during manufacturing.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram showing a configuration example of a self-diagnosis function hardware of a control device according to a first embodiment.

FIG. 2 is a block diagram showing an example of a self-diagnosis sequence circuit.

FIG. 3 is a block diagram showing an example of a microprocessor diagnosis determination circuit.

FIG. 4 is an explanatory diagram showing a state transition example of a sequencer circuit.

FIG. 5 is a block circuit diagram showing a hardware configuration example of a self-diagnosis function of the control device according to the second embodiment.

FIG. 6 is a block diagram showing an example of a self-diagnosis sequence circuit.

FIG. 7 is an explanatory diagram showing a state transition example of a sequencer circuit.

FIG. 8 is a block circuit diagram showing a hardware configuration example of a self-diagnosis function of a control device according to a third embodiment.

FIG. 9 is a block diagram showing an example of a self-diagnosis sequence circuit.

FIG. 10 is a block diagram showing an example of a microprocessor diagnosis determination circuit.

FIG. 11 is an explanatory diagram showing a state transition example of a sequencer circuit.

FIG. 12 is a block circuit diagram showing a hardware configuration of a control device having a self-diagnosis function according to a conventional example.

FIG. 13 is a block circuit diagram showing a hardware configuration of a control function block.

[Explanation of symbols]

Reference numeral 101 ... Microprocessor 102 ... Control program storage memory 103 ... Power-on reset function circuit 104 ... Operator reset acceptance circuit 110-112 ... Control function (circuit, block) 120 ... Abnormality notification function circuit 140 ... Microprocessor diagnostic determination circuit 150 ... Clock generation circuit 160 ... Software reset generation circuit 170 ... Error code display function (circuit, block) 200 to 202 ... Control target (device) 1101 ... Command register 1102 ... Actual processing function (circuit, block) 1103 ... Result display register 1301 Sequencer circuit 1302 Microprocessor diagnostic program / address storage circuit 1303 Multiplexer circuit 1401 Microprocessor diagnostic result register 1402 Diagnostic result expected value storage circuit 14 03 ... Comparator.

Claims (3)

[Claims] 1. A self-diagnosis method for a control device, comprising: a microprocessor for controlling control; and a memory for storing a control program, which self-diagnoses each function in the device before actual control processing is executed. A self-diagnosis sequence circuit that controls the entire diagnostic function and a microprocessor diagnosis determination circuit that allows the microprocessor to write the execution result of the microprocessor diagnostic program and determine the execution result are provided. When the control process is restarted or the control command is restarted, the self-diagnosis sequence circuit stores the microprocessor and control program before the actual control process by the microprocessor is executed. Performs self-diagnosis of memory peripheral circuits and confirms that they are operating normally. Only if it is determined that, giving control to the microprocessor, to execute the subsequent normal control process, the self-diagnosis system of the control device, characterized in that. 2. A self-diagnosis method for a control device or system, comprising a microprocessor for controlling control and a memory for storing a control program, and self-diagnosing each function in the device before actual control processing is executed. The microprocessor diagnostic program for diagnosing its function is stored in a specific area of the control program storage memory, and the self-diagnosis sequence circuit that controls the entire microprocessor self-diagnosis function and the microprocessor A microprocessor diagnosis result judgment circuit for writing the execution result and judging this result is provided.The self-diagnosis sequence circuit directly resets the reset signal to the microprocessor by the operator's operation or the power-on reset. (2) It is loaded into this circuit without giving it to the processor, and a part of the address for the control program storage memory generated by the microprocessor is loaded into the self-diagnosis sequence circuit, and is passed through this circuit to the control program storage memory. The address to be given is generated, and the self-diagnosis sequence circuit resets the microprocessor once at the time of power-on reset, and at the same time, sets the address of the preset microprocessor diagnosis program to the control program storage memory. The microprocessor diagnostic routine is executed by causing the microprocessor to execute a microprocessor diagnostic routine by releasing the reset to the microprocessor. Instructed to write to the result judgment circuit, the microprocessor diagnosis result judgment circuit stores in advance the correct data obtained during normal execution as an expected value, and compares it with the result data written by the microprocessor diagnosis. Then, the self-diagnosis sequence circuit scans the judgment result of this microprocessor diagnosis result judgment circuit after a certain period of time, and if it is normal, resets it to the microprocessor again. Then, the address given to the memory for storing the control program is switched to the address output by the microprocessor, the reset is released, and the control right of the device is handed over to the microprocessor. Notify the outside of the abnormality and reset the microprocessor. A self-diagnosis method for control devices, characterized by preventing malfunctions and erroneous control of the device by leaving it on. 3. The maintenance of the device according to claim 2, wherein the microprocessor diagnostic is divided into steps, and a signal bundle for address selection of the microprocessor diagnostic program and an error code display function at the time of abnormality detection are added. A self-diagnosis method for a control device, which is characterized by improving