JP2009157561A - Measurement control apparatus, and memory element protection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the probability of an operator making an error in determination and suppress the probability of a memory element reaching the end of its life. <P>SOLUTION: A measurement control apparatus comprises: an EEPROM 3 for storing parameters; a write detection part 50 for counting the number of times of writing of parameters to the EEPROM 3 by each parameter; and warning issuing means (a determination part 51, an LED 6, and an LED lighting processing part 7) for comparing the number of times of writing by each parameter with the upper limit of the predetermined number of times of writing by each parameter, and issuing a warning when the number of times of writing of at least one parameter exceeds the upper limit of the number of times of writing set for this parameter. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a measurement control device such as a temperature controller, and more particularly to a measurement control device and a storage element protection method capable of suppressing the probability that a storage element such as an EEPROM mounted in the measurement control apparatus reaches the end of its life. Is.

  Loop level measurement control devices such as temperature controllers have parameters that need to be set and stored in advance, and EEPROM (Electronically Erasable and Programmable Read Only Memory) is used as a device for storage. . The EEPROM has a life as a characteristic of the hardware. When the number of times of writing increases, the EEPROM reaches the life and does not operate normally. In the measurement control device, it is inevitable that writing / updating is necessary during practical use as a property of parameters to be written to the EEPROM. On the other hand, since it is incorporated into the apparatus as a measurement control device and used continuously, it is not easy to replace the EEPROM, and at the same time, it is not preferable that the EEPROM reaches its life and does not operate normally.

  In many cases, writing to the EEPROM in the measurement control device is programmed to be automatically performed using a communication function or the like. Since writing to the EEPROM is recognized by programmers as a common sense, it is usually not designed to write to the EEPROM frequently. That is, the main cause of the situation in which the EEPROM reaches the end of its life and does not operate normally in the measurement control device is a programmer's design error or program error.

  Patent Document 1 discloses a storage element monitoring protection device that counts the number of times of writing to an EEPROM within a specific time range and issues an alarm when the number of times of writing exceeds the upper limit of the number of times of writing.

JP-A-5-73435

  In the measurement control device, there are cases where the number of times of writing to the EEPROM must be increased within a certain time. As such a case, for example, there is a time of updating a parameter value accompanying a process switching such as a change of a control target. At the time of this update, many parameter values stored in the EEPROM are updated simultaneously.

  If the technique disclosed in Patent Document 1 is applied to a measurement control device, an alarm may be generated when a large number of parameters are updated as described above. There is a problem of judging. In addition, if an alarm occurs frequently due to parameter updates, the operator will habitually generate this alarm and consider it as a problem, so when an alarm is generated due to an abnormal operation due to a real program error, Abnormal behavior may be overlooked as no problem. When such a determination error occurs, there is a high risk that the EEPROM will reach the end of its life early.

In addition, when writing to the EEPROM frequently occurs due to program mistakes, such writing may continue even if the number of times of writing to the EEPROM is a common number of times within a specific time range. In this case, even if the technique disclosed in Patent Document 1 is applied to the measurement control device, the number of times of writing to the EEPROM within a specific time range does not exceed the upper limit of the number of times of writing, so an alarm is generated even though the operation is abnormal. Does not occur. Therefore, there is a high risk that the EEPROM will reach the end of its life early.
The above-described problems are not limited to EEPROM, and similarly occur in memory elements that have a limited number of writings.

  The present invention has been made in order to solve the above-described problems. A measurement control device and a storage element capable of reducing the probability that an operator makes a mistake and reducing the probability that a storage element such as an EEPROM will reach the end of its life will be provided. It aims to provide a protection method.

The measurement control device of the present invention includes a storage element that stores a parameter used in the measurement control device, a write detection unit that counts the number of times of writing the parameter to the storage element for each parameter, and the number of times of writing for each parameter. A warning generation means for comparing a preset write count upper limit value for each parameter and issuing an alarm when the write count of at least one parameter exceeds the write count upper limit value set for this parameter is provided. Is.
Further, according to one configuration example of the measurement control device of the present invention, when the number of times of writing the parameter exceeds the upper limit value of the number of times of writing set for the parameter, the parameter is written to the storage element. Write prohibition means for prohibiting is provided.
In addition, the measurement control device of the present invention includes a storage element that stores a parameter used in the measurement control device, a write detection unit that counts the number of times of writing the parameter to the storage element for each parameter attribute, Compares the write count for each attribute with the preset write count upper limit for each attribute of the preset parameter, and alerts if the write count for at least one attribute exceeds the write count upper limit set for this attribute Alarm generating means for emitting
In addition, according to one configuration example of the measurement control device of the present invention, when the number of writes for each attribute exceeds the upper limit value of the number of writes set for the attribute, the parameter of the attribute is stored in the storage element. Is provided with write prohibiting means for prohibiting writing of.
Further, according to one configuration example of the measurement control device of the present invention, for the low change frequency parameter whose change frequency is lower than the normal change frequency parameter, the write number upper limit value is smaller than the write number upper limit value for the normal change frequency parameter. Is set in advance.

Further, the measurement control device of the present invention, a storage element for storing parameters used in the measurement control device, a write detection means for detecting writing of parameters to the storage element using a communication function from an external device, And a notification means for notifying the user that writing to the storage element using the communication function has been performed when the writing is detected.
In addition, one configuration example of the measurement control device of the present invention further includes parameter registration means for pre-registering a low change frequency parameter whose change frequency is lower than the normal change frequency parameter, and the notification means If the target parameter is a normal change frequency parameter, the user is notified for a first notification time defined in advance for the normal change frequency parameter, and the write target parameter is registered in the parameter registration means. When the low change frequency parameter is set, the user is notified only for a second notification time that is defined in advance, which is longer than the first notification time.

In addition, the storage element protection method of the present invention is a write detection that counts the number of times the parameter is written for each parameter when the parameter is written to the storage element that stores the parameter used in the measurement control device. When the procedure and the number of times of writing for each parameter are compared with the preset number of times of writing for each parameter, and the number of times of writing for at least one parameter exceeds the number of times of writing set for this parameter And an alarm generation procedure for generating an alarm.
Also, the storage element protection method of the present invention counts the number of parameter writes for each parameter attribute when the parameter is written to the storage element that stores the parameter used in the measurement control device. The write detection procedure is compared with the write count for each attribute of the parameter and the preset write count upper limit value for each parameter attribute, and the write count of at least one attribute is the write count set for this attribute. An alarm generation procedure for generating an alarm when an upper limit value is exceeded.

In addition, the memory element protection method of the present invention detects this writing when a parameter is written using a communication function from an external device to a memory element that stores the parameter used in the measurement control device. And a notification procedure for notifying the user that writing to the storage element using the communication function has been performed when the writing is detected.
Further, in one configuration example of the storage element protection method of the present invention, the notification procedure includes a first pre-defined for the normal change frequency parameter when the parameter to be written is a normal change frequency parameter. When the notification is made to the user only for the notification time and the parameter to be written is a low change frequency parameter whose change frequency is lower than that of the normal change frequency parameter, the first predetermined time longer than the first notification time is set. The user is notified only for the notification time of 2.

  According to the present invention, the number of times of writing parameters to the storage element is counted for each parameter, the number of times of writing for each parameter is compared with a preset number of times of writing for each parameter, and the number of times of writing of at least one parameter is compared. However, by issuing an alarm when the upper limit of the number of times of writing set for this parameter is exceeded, it is possible to reduce the probability that the operator will make a mistake and to keep the probability that the storage element will reach the end of its life. it can.

  Further, according to the present invention, when the number of parameter writes exceeds the upper limit value of the number of writes set for this parameter, the storage element reaches the end of its life by prohibiting writing of this parameter to the storage element. Probability can be kept low.

  Further, in the present invention, the number of parameter writes to the storage element is counted for each parameter attribute, and the write count for each parameter attribute is compared with a preset write count upper limit value for each parameter attribute, By issuing an alarm when the write count of one attribute exceeds the write count upper limit set for this attribute, it is possible to reduce the probability that the operator makes a mistake and the storage element reaches the end of its life. Probability can be kept low.

  Further, according to the present invention, when the number of times of writing for each attribute exceeds the upper limit value of the number of times of writing set for this attribute, the memory element has a lifetime by prohibiting writing of the parameter of this attribute to the memory element. The probability of reaching can be kept low.

  Further, in the present invention, for the low change frequency parameter, by setting a lower write number upper limit value than the write number upper limit value for the normal change frequency parameter, in the case where the possibility of normal writing is clearly high, It is possible to avoid the number of writings from reaching the upper limit of the number of writings, and at the same time, the number of writings should be within the upper limit of the number of writings when there is a high possibility of a design error or programming error. Can be avoided.

  Further, in the present invention, when parameter writing from an external device to the storage element using the communication function is detected, the user is notified that the writing to the storage element using the communication function has been performed. Can do.

  In the present invention, when the parameter to be written is a normal change frequency parameter, the user is notified for the first notification time defined in advance for the normal change frequency parameter, and the parameter to be written is set. Is a low change frequency parameter, by notifying the user for a predetermined second notification time that is longer than the first notification time, there is clearly a high possibility of normal writing In addition, it is possible to prevent the notification from continuing, and at the same time, it is possible to reduce the probability that the notification is overlooked when there is a high possibility of a design error or a program error.

[Principle of Invention 1]
The lifetime of the EEPROM is not simply determined by the total number of writes, but needs to be considered by the number of writes in a specific write area. For example, even if the same writing is performed 100,000 times, writing is performed 100,000 times concentrated in one writing area, and writing is performed 10,000 times in 10 writing areas. In some cases, the latter has an overwhelmingly lower probability of reaching life.

  Thus, the inventor has paid attention to the fact that it is appropriate to count the number of writes for each writing area rather than simply counting the number of times of writing to the EEPROM. In addition, in the measurement control device, the inventor has noted that the number of times of common writing within a specific time range is limited to the number of common sense depending on the nature of each parameter. When the frequency of writing to the EEPROM by communication or the like is counted for each parameter (substantially for each writing area) and the upper limit of the number of times of writing within a unit time for each preset parameter is exceeded The inventor has conceived that outputting an alarm is effective for solving the problem.

  For example, when 100 parameters are updated when the parameter value is updated due to process switching such as changing the control target, the number of times of writing to the EEPROM is 100. The number of times of writing is only once. In other words, if the number of write operations for each parameter reaches, for example, 3 in such a situation, there is a high possibility of a program error. By counting by parameter, it is easy to make an appropriate determination even in the parameter update operation unique to the measurement control device.

[Principle of Invention 2]
Furthermore, if writing to the EEPROM is prohibited when the number of times of writing in the unit time for each parameter to the EEPROM exceeds the upper limit of the number of times of writing set for the parameter, it is effective for solving the problem. In particular, the inventor arrived.

[Principle 3 of the invention]
In the measurement control device, a normal change frequency parameter (for example, a target value SP or PID parameter in the case of a temperature controller) and a write that are premised to be changed in accordance with a change of a processing target during online operation, Although not prohibited, there are low change frequency parameters (for example, input range type, control cycle, output type, etc. for a temperature controller) that are not changed during online actual operation if the usage method is determined. Therefore, when the low change frequency parameter is changed, there is a high possibility of an operator design error or a program error even if the number of times of writing to the EEPROM is small. Therefore, the inventor believes that it is appropriate to preliminarily specify a larger number of write times upper limit for the normal change frequency parameter, and to prescribe a smaller number of write times upper limit (for example, once) for the low change frequency parameter. I thought.

  By changing the upper limit of the number of writes with the normal change frequency parameter and the low change frequency parameter, it is possible to avoid reaching the upper limit of the number of writes when there is clearly a high possibility of normal writing. On the other hand, when there is a high possibility of a design error or a program error, it is possible to avoid falling within the upper limit of the number of times of writing.

[Principle of Invention 4]
Regarding writing to the EEPROM, in many cases, not only the programmer but also the operator of the measurement control device recognizes a common sense range. Therefore, the inventor has noticed that it is easy to avoid an abnormal state even if the operator can recognize the frequency of writing to the EEPROM by communication or the like. Then, in all cases where writing to the EEPROM is performed by the communication function during online operation, notification (display) that can be recognized by the operator is performed only for a predetermined time. The inventor has conceived that this is effective.

  At the time of process switching such as changing the control target, the frequency of notification indicating that writing to the EEPROM has been increased, but an operator who recognizes that there are many writings to the EEPROM may make an erroneous determination. Is low. In addition, if it is not at the time of process switching and if a notification indicating that writing to the EEPROM has been performed is made, an operator who recognizes that writing to the EEPROM is not expected is an abnormal operation. It becomes possible to judge.

[Principle 5 of the invention]
Furthermore, if the normal change frequency parameter is notified (displayed) only for a predetermined short time, and the low change frequency parameter is notified for a longer time than the normal change frequency parameter, the problem can be further solved. The inventor has conceived that it is effective. By changing the duration of the notification with the normal change frequency parameter and the low change frequency parameter, it is possible to avoid continuing the notification when there is a clear possibility of normal writing, and at the same time, it becomes clear When there is a high possibility of a design error or a program error, it is possible to reduce the probability that a notification is missed.

[First Embodiment]
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a measurement control device according to the first embodiment of the present invention. This embodiment corresponds to Principle 1 of the invention described above. The measurement control device includes a PID control unit 1 that controls a control target, an input unit 2 such as a keyboard for an operator (user) of the measurement control device to input parameters, an EEPROM 3, and a RAM (Random Access Memory). 4, a writing / reading unit 5 that performs writing / reading to / from the EEPROM 3 or the RAM 4 as required, an LED 6 for alarm notification, and an LED lighting process for lighting the LED 6 in response to the alarm notification from the writing / reading unit 5 And a communication interface unit 8 for connecting the measurement control device and an external device (not shown). The writing / reading unit 5 includes a writing detection unit 50 that detects writing to the EEPROM 3 and a determination unit 51 that performs alarm notification. The determination unit 51, the LED 6, and the LED lighting processing unit 7 constitute an alarm generation unit.

  FIG. 2 is a diagram illustrating an example of a temperature control system to which the measurement control device of the present embodiment is applied. In the example of FIG. 2, a heater 12 and a temperature sensor 13 are installed inside the heat treatment furnace 11. The temperature sensor 13 measures the temperature PV of the air heated by the heater 12. The temperature controller 10 calculates the manipulated variable MV so that the temperature PV matches the set value SP. The power adjuster 14 determines power according to the operation amount MV, and supplies the determined power to the heater 12 through the power supply circuit 15. Thus, the temperature controller 10 controls the temperature in the heat treatment furnace 11. The measurement control device is provided inside the temperature controller 10. In FIG. 2, a PLC (Programmable Logic Controller) 16 is a host device that controls the temperature controller 10 using a communication function.

  Hereinafter, the operation of the measurement control device will be described. The EEPROM 3 includes a set value SP, PID parameters (proportional band P, integration time I, derivative time D), control amount bias PVbi applied to the control amount PV, output upper and lower limit values MVli of the operation amount MV, and an input range of the control amount PV. Parameters such as the type PVra, the control period dt, and the output type MVva of the manipulated variable MV are preset and stored. Examples of the input range type PVra include a measurement range range of the temperature sensor 13 of the temperature control system. The output types MVva include current output and voltage output. There are three types of parameters, operating parameters, setting / adjusting parameters, and monitoring parameters.

  The operation parameter is a parameter on the premise that the parameter is changed in accordance with the change of the control target during the operation of the measurement control device. Examples of the operation parameters include a set value SP, an SP set, and a PID set. The SP set includes a plurality of setting values SP and a plurality of codes assigned to each of them. When a specific code is input from the input unit 2 or the communication interface unit 8 according to the control target, the set value SP corresponding to the code is read out. Similarly, the PID set includes a plurality of combinations of PID parameters (proportional band P, integration time I, derivative time D) and a plurality of codes assigned to each of these combinations. When a specific code is input from the input unit 2 or the communication interface unit 8 according to the control target, a combination of PID parameters corresponding to the code is read out.

  The parameter for setting / adjustment is a parameter that is set / adjusted according to the usage method of peripheral devices such as sensors and actuators and measurement control devices. Examples of the setting / adjustment parameters include a control amount bias PVbi, a PID parameter, and an output upper / lower limit value MVli. The PID parameter may be defined as an operation parameter or a setting / adjustment parameter.

The monitor parameter is a parameter that is not prohibited from being written to the EEPROM 3, but is not changed during operation if the method of use is determined. Examples of the monitoring parameters include an input range type PVra, a control cycle dt, and an output type MVva.
The above operation parameters, setting / adjustment parameters, and monitoring parameters include predetermined attributes such as “1” for operation parameters, “2” for setting / adjustment parameters, and “0” for monitoring parameters. A code is assigned.

3A is a diagram showing an example of the contents stored in the EEPROM 3, and FIG. 3B is a diagram showing an example of the contents stored in the RAM 4 corresponding to the contents stored in the EEPROM 3. As shown in FIG.
Each parameter is stored in advance in the parameter storage area 30 of the EEPROM 3, and an attribute code is stored in advance in the attribute code storage area 31 for each parameter. Further, the EEPROM 3 has a write count upper limit storage area 32 that stores in advance the upper limit value of the number of writes in the unit time in the EEPROM 3 for each parameter, and a write count in which the lower limit value of the number of writes in the unit time is stored in advance for each parameter. There is a lower limit storage area 33. Note that the upper limit value of the number of times of writing is set to 1 for the monitor parameter.

  The writing / reading unit 5 reads out the attribute code of each parameter, the writing number upper limit value, and the writing number lower limit value from the EEPROM 3 when starting the measurement control device, and develops them on the RAM 4. The attribute code is stored for each parameter in the attribute code storage area 40 of the RAM 4, the write count upper limit is stored for each parameter in the write count upper limit storage area 42, and the write count lower limit is the write count lower limit storage area. 43 is stored for each parameter. Further, the RAM 4 stores a write count storage area 41 for storing the number of writes to the EEPROM 3 within a unit time for each parameter, and an alarm generation flag storage for storing an alarm generation flag indicating whether an alarm has occurred for each parameter. There are an area 44 and an alarm generation history storage area 45 for storing an alarm generation history for each parameter attribute.

  The PID control unit 1 receives the set value SP, the PID parameter, the control amount bias PVbi, the output upper / lower limit value MVli, the input range type PVra, the control period dt, and the output type MVva read from the sensor through the write / read unit 5. Based on the control amount PV (temperature in the example of FIG. 2), the operation amount MV is calculated by a known PID control calculation algorithm. In the example of FIG. 2, the manipulated variable MV is output to the power regulator 14.

The writing / reading unit 5 writes data to the EEPROM 3 or the RAM 4 in accordance with an input from the PID control unit 1, the input unit 2, or the communication interface unit 8. A write detection unit 50 in the write / read unit 5 detects writing to the EEPROM 3. The writing / reading unit 5 reads data from the EEPROM 3 or the RAM 4 as necessary.
FIG. 4 and FIG. 5 are flowcharts showing operations related to writing to the EEPROM 3 by the writing / reading unit 5.

  First, when a write request (parameter change request) to the EEPROM 3 is generated by a parameter input from the input unit 2 or the communication interface unit 8 (YES in step S100 in FIG. 4), the write / read unit 5 sets the input parameter. Writing to the EEPROM 3 (step S101). Thereby, the parameter stored in the EEPROM 3 is changed.

  When the writing detecting unit 50 detects writing of a parameter to the EEPROM 3, the writing detecting unit 50 obtains an attribute code of the parameter from the attribute code storage area 40 of the RAM 4 (step S102), and stores the parameter stored in the writing count storage area 41. The number of times of writing is increased by 1 (step S103).

  Subsequently, the determination unit 51 compares the parameter write count updated in step S103 with the parameter write count upper limit value stored in the write count upper limit storage area 42 (step S104). When the parameter write count exceeds the write count upper limit value, the determination unit 51 sets the alarm generation flag of the parameter stored in the alarm generation flag storage area 44 to a value indicating the alarm occurrence, and outputs an alarm notification signal. Is output to the LED lighting processing unit 7 (step S105). In response to the warning notification signal, the LED lighting processing unit 7 turns on the LED 6 to give a warning to the operator. Further, the determination unit 51 sets a history indicating that an alarm has occurred in the alarm occurrence history storage area 45 of the corresponding attribute according to the attribute code of the parameter obtained in step S102 (step S106).

  Further, the determination unit 51 performs the write count subtraction process as shown in FIG. 5 every unit time (for example, 10 seconds). That is, when the unit time has elapsed (YES in step S200), the determination unit 51 refers to the write count storage area 41 to check whether the write count of all parameters is 0 (step S201).

  When there is a parameter whose write count is not 0, the determination unit 51 reduces the write count of the parameter stored in the write count storage area 41 by 1 (step S202). Subsequently, the determination unit 51 compares the parameter write count updated in step S202 with the parameter write count lower limit value stored in the write count lower limit storage area 43 (step S203). When the parameter write count is equal to or smaller than the write count lower limit value, the determination unit 51 resets the alarm occurrence flag of the parameter stored in the alarm occurrence flag storage area 44 to a value indicating alarm release, and issues an alarm release notification. A signal is output to the LED lighting processing unit 7 (step S204). In response to the alarm release notification signal, the LED lighting processing unit 7 turns off the LED 6. The alarm generation history stored in the alarm generation history storage area 45 remains.

  As described above, in the present embodiment, the number of times of writing parameters to the EEPROM is counted for each parameter, the number of times of writing for each parameter is compared with a preset number of times of writing for each parameter, and at least one By issuing an alarm when the number of parameter writes exceeds the upper limit for the number of writes set for this parameter, an alarm can be issued when the number of parameter writes exceeds a common number. Can reduce the probability of misjudgment, and the probability that the EEPROM reaches the end of its life can be kept low.

[Second Embodiment]
FIG. 6 is a block diagram showing a configuration of a measurement control device according to the second embodiment of the present invention. This embodiment corresponds to Principle 2 of the invention described above. The write / read unit 5 a according to the present embodiment includes a write inhibit unit 52 in addition to the write detection unit 50 and the determination unit 51.

When a parameter write request to the EEPROM 3 is generated, the write prohibition unit 52 checks the number of times of writing the parameter stored in the write number storage area 41, and this write number is stored in the write number upper limit value storage area 42. When the stored upper limit value of the parameter is exceeded, the alarm generation flag of the parameter stored in the alarm generation flag storage area 44 is set to issue an alarm, and the parameter to the EEPROM 3 is set. Prohibit writing. Since parameter writing is prohibited, it goes without saying that the number of times the parameter is written does not increase.
Thus, in this embodiment, the probability that the EEPROM reaches the end of its life can be kept low.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. In the second embodiment, the upper limit value of the number of times of writing for alarm generation and the upper limit value of the number of times of writing for prohibiting writing are made common, but they may be set separately. In this case, the upper limit of the number of times of writing for the EEPROM 3 and the RAM 4 and the upper limit value of the number of times of writing for alarm generation and the upper limit of the number of times of writing for prohibiting writing are set for each parameter. Since the configuration of the measurement control device is the same as that of the second embodiment, the operation of this embodiment will be described using the reference numerals in FIG.

  FIG. 7 is a flowchart showing an operation related to writing to the EEPROM 3 by the writing / reading unit 5a. First, when a write request to the EEPROM 3 is generated by the parameter input from the input unit 2 or the communication interface unit 8 (YES in step S300 in FIG. 7), the write detection unit 50 of the write / read unit 5a sets the input parameters. The corresponding attribute code is obtained from the attribute code storage area 40 of the RAM 4 (step S301), and the writing count of the parameter stored in the writing count storage area 41 is increased by 1 (step S302).

  Subsequently, the write prohibition unit 52 compares the parameter write count updated in step S302 with the write prohibition write count upper limit value stored in the write count upper limit storage area 42 (step S303). . When the parameter write count is equal to or less than the write prohibition upper limit value for write prohibition, the write prohibit section 52 permits the parameter to be written to the EEPROM 3. Thereby, the writing / reading unit 5a writes the parameter input from the input unit 2 or the communication interface unit 8 to the EEPROM 3 (step S304).

  Next, the determination unit 51 compares the parameter write count updated at step 302 with the alarm occurrence write count upper limit value stored in the write count upper limit storage area 42 (step S305). The processing in steps S306 and S307 when the number of parameter writes exceeds the upper limit of the number of times of writing for alarm generation is the same as steps S105 and S106 in FIG.

On the other hand, if the parameter write count exceeds the write prohibition upper limit value for write prohibition in step S303, the write prohibition unit 52 updates the parameter write count to the same value as the write prohibition write count upper limit value ( In step S308, writing of the parameter to the EEPROM 3 is prohibited, and a write disable notification is sent to the request source (step S309). As a method of notifying the operator that writing is impossible, there is a method of displaying that writing to the EEPROM 3 is impossible, for example, on a display device (not shown). Further, in the case of a write request using the communication function, a response indicating that the write cannot be performed may be returned to the request source via the communication interface unit 8.
The number-of-writes subtraction process performed by the determination unit 51 per unit time is as shown in FIG.

[Fourth Embodiment]
In the first to third embodiments, an attribute code is assigned to each parameter. The addresses on the EEPROM 3 and the RAM 4 are assigned, for example, the operating parameters are in the 100s, the setting / adjusting parameters are in the 200s, and the monitoring parameters. In the 300 range, the write / read units 5 and 5a can determine the attribute of the parameter only by the address without having an attribute code for each parameter on the RAM 4.

[Fifth Embodiment]
In the first to third embodiments, the upper limit number of writing times and the lower limit number of writing times are set in advance for each parameter, and the writing number is counted for each parameter. A value and a lower limit value of the number of times of writing may be set, and the number of times of writing may be counted for each attribute.

FIG. 8A shows an example of the contents stored in the EEPROM 3 according to the present embodiment, and FIG. 8B shows an example of the contents stored in the RAM 4 corresponding to the contents stored in the EEPROM 3.
The parameter storage area 30 and the attribute code storage area 31 of the EEPROM 3 are the same as those in FIG. The EEPROM 3 stores in advance the upper limit value of the number of times of writing to the EEPROM 3 within a unit time (the upper limit value of the number of times of writing for alarm generation and write prohibition when applied to the third embodiment) for each parameter attribute. There is a write count upper limit storage area 32a and a write count lower limit storage area 33a for storing the write count lower limit value within a unit time in advance for each parameter attribute.

  The writing / reading units 5 and 5a read the attribute code of each parameter, the writing number upper limit value, and the writing number lower limit value from the EEPROM 3 when the measurement control device is activated, and develop them on the RAM 4. The attribute code is stored in the attribute code storage area 40 of the RAM 4 for each parameter attribute, the write count upper limit value is stored for each attribute in the write count upper limit storage area 42a, and the write count lower limit value is the write count lower limit value. Each attribute is stored in the storage area 43a. The RAM 4 stores a write count storage area 41a for storing the number of writes to the EEPROM 3 within a unit time for each attribute, and an alarm generation flag storage for storing an alarm generation flag indicating whether an alarm has occurred for each attribute. There are an area 44a and an alarm occurrence history storage area 45 for storing an alarm occurrence history for each attribute.

  The configuration and operation of the measurement control device are the same as those in the first to third embodiments, and the processes in steps S103 to S106 in FIG. 4, steps S201 to S204 in FIG. 5, and S302, S303, and S305 to S308 in FIG. May be performed for each parameter attribute.

[Sixth Embodiment]
In the first to fifth embodiments, how to define the upper limit value of the number of times of writing is not described in detail. However, as described in Principle 3 of the invention, the normal change frequency parameter (operating parameter and setting / It is also possible to specify a larger number of write times upper limit for the adjustment parameter) and a lower number of write times upper limit than the normal change frequency parameter for the low change frequency parameter (monitor parameter).

  By changing the upper limit of the number of writes with the normal change frequency parameter and the low change frequency parameter, it is possible to avoid the number of writes reaching the upper limit of the number of writes when there is clearly a high possibility of normal writing. At the same time, conversely, when there is a high possibility of a design error or a program error, it is possible to avoid the number of writings from being within the upper limit of the number of writings.

[Seventh Embodiment]
Next, a seventh embodiment of the present invention will be described. This embodiment corresponds to Principle 4 of the invention described above. Since the configuration of the measurement control device is the same as that of the first embodiment, description will be made using the reference numerals in FIG. Here, the determination part 51, LED6, and LED lighting process part 7 comprise the notification means. FIG. 9 is a flowchart showing an operation related to writing to the EEPROM 3 by the writing / reading unit 5 of the present embodiment.

  The writing / reading unit 5 writes parameters to the EEPROM 3 in response to an input from the input unit 2 or the communication interface unit 8. At this time, the write detection unit 50 detects this write when a write request to the EEPROM 3 is generated, for example, by parameter input from the host PLC 16 via the communication interface unit 8 (YES in step S400 in FIG. 9).

If the parameter writing to the EEPROM 3 using the communication function is detected, the determination unit 51 outputs a write notification signal to the LED lighting processing unit 7 (step S401).
In response to the write notification signal, the LED lighting processing unit 7 lights the LED 6 for a predetermined time (for example, about one second during a control cycle and about 0.2 seconds for a normal temperature controller). As a result, it is possible to notify the operator that data has been written to the EEPROM 3 from the outside via the communication interface unit 8.

[Eighth Embodiment]
Next, an eighth embodiment of the present invention will be described. This embodiment corresponds to Principle 5 of the invention described above. FIG. 10 is a block diagram showing a configuration of a measurement control device according to the eighth embodiment of the present invention. The measurement control device includes a PID control unit 1, an input unit 2, an EEPROM 3, a RAM 4, a writing / reading unit 5, an LED lighting processing unit 7, an LED 6, a communication interface unit 8, and a low change frequency parameter. And a parameter registration unit 9 for previously registering.

FIG. 11 is a flowchart showing an operation related to writing to the EEPROM 3 by the writing / reading unit 5 of the present embodiment.
The writing / reading unit 5 writes parameters to the EEPROM 3 in accordance with an input from the input unit 2 or the communication interface unit 8. At this time, when a write request to the EEPROM 3 is generated by parameter input via the communication interface unit 8, the write detection unit 50 detects this write (YES in step S500 in FIG. 11).

  When the parameter writing to the EEPROM 3 using the communication function is detected, the determination unit 51 determines whether the parameter to be written is a low change frequency parameter registered in the parameter registration unit 9 ( Step S501). An example of the low change frequency parameter is a monitoring parameter.

When the parameter to be written is a low change frequency parameter, the determination unit 51 outputs a low change frequency parameter write notification signal to the LED lighting processing unit 7 (step S502).
When the LED lighting processing unit 7 receives the low change frequency parameter write notification signal from the determination unit 51, the LED lighting processing unit 7 is a predetermined time for the low change frequency parameter (for example, 10 control cycles, and a normal temperature controller). If so, the LED 6 is turned on only for about 2 seconds).

In addition, when the parameter to be written is a normal change frequency parameter that is not registered in the parameter registration unit 9, the determination unit 51 outputs a normal change frequency parameter write notification signal to the LED lighting processing unit 7 (step S503). ).
When the LED lighting processing unit 7 receives the normal change frequency parameter write notification signal, the LED lighting processing unit 7 is a short time defined in advance for the normal change frequency parameter (for example, during one control cycle and is a normal temperature controller). The LED 6 is turned on only for about 0.2 seconds).

  However, even in the case of a low change frequency parameter, an urgent or unavoidable writing instruction may be given due to some circumstances (for example, when an error in the initial setting is noticed and corrected), so writing to the EEPROM 3 is executed. Shall.

  In the present embodiment, it is possible to avoid continuing notification when there is a high possibility of normal writing by changing the duration of notification with the normal change frequency parameter and the low change frequency parameter. At the same time, on the contrary, when there is a high possibility that it is clearly a design error or a program error, it is possible to reduce the probability that the notification is overlooked.

  The measurement control device described in the first to eighth embodiments can be realized by a computer having a CPU, a storage device, and an interface, and a program for controlling these hardware resources. The CPU executes the processes described in the first to eighth embodiments in accordance with a program stored in the storage device.

In this embodiment, the EEPROM is described as an example. However, the present invention is not limited to the EEPROM, and the present invention is effective as long as the memory element has a limited number of times of writing.
In the first to eighth embodiments, an LED is used as a device for generating an alarm or writing notification. However, the present invention is not limited to this. For example, a display device such as an LCD may be used.

  The present invention can be applied to a device equipped with a storage element such as an EEPROM that has a limited number of times of writing.

It is a block diagram which shows the structure of the measurement control apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows one example of the temperature control system to which the measurement control apparatus which concerns on the 1st Embodiment of this invention is applied. It is a figure which shows the example of the memory content of EEPROM and RAM of the measurement control apparatus which concerns on the 1st Embodiment of this invention. It is a flowchart which shows operation | movement of the writing / reading part of the measurement control apparatus which concerns on the 1st Embodiment of this invention. It is a flowchart which shows operation | movement of the writing / reading part of the measurement control apparatus which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the structure of the measurement control apparatus which concerns on the 2nd Embodiment of this invention. It is a flowchart which shows operation | movement of the writing / reading part of the measurement control apparatus which concerns on the 3rd Embodiment of this invention. It is a figure which shows the example of the memory content of EEPROM and RAM of the measurement control apparatus which concerns on the 5th Embodiment of this invention. It is a flowchart which shows operation | movement of the writing / reading part of the measurement control apparatus which concerns on the 7th Embodiment of this invention. It is a block diagram which shows the structure of the measurement control apparatus which concerns on the 8th Embodiment of this invention. It is a flowchart which shows operation | movement of the writing / reading part of the measurement control apparatus which concerns on the 8th Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... PID control part, 2 ... Input part, 3 ... EEPROM, 4 ... RAM, 5, 5a ... Write / read part, 6 ... LED, 7 ... LED lighting process part, 8 ... Communication interface part, 9 ... Parameter registration part DESCRIPTION OF SYMBOLS 10 ... Temperature controller, 11 ... Heat processing furnace, 12 ... Heater, 13 ... Temperature sensor, 14 ... Power regulator, 15 ... Power supply circuit, 16 ... PLC, 50 ... Write detection part, 51 ... Determination part, 52 ... write-protection section.

Claims (11)

A storage element for storing parameters used in the measurement control device;
Write detection means for counting the number of parameter writes to this storage element for each parameter;
Compare the number of writes for each parameter with a preset upper limit of the number of writes for each parameter, and issue an alarm if the number of writes of at least one parameter exceeds the upper limit of the number of writes set for this parameter. A measurement control device comprising an alarm generating means for emitting. The measurement control device according to claim 1,
The measurement control further comprises a write prohibiting means for prohibiting writing of the parameter to the storage element when the number of times of writing of the parameter exceeds an upper limit value of the number of writings set for the parameter. machine. A storage element for storing parameters used in the measurement control device;
Write detection means for counting the number of parameter writes to this storage element for each parameter attribute;
The write count for each attribute of the parameter is compared with a preset write count upper limit value for each parameter attribute, and the write count of at least one attribute exceeds the write count upper limit value set for this attribute. A measurement control device comprising alarm generation means for issuing an alarm in case. In the measurement control device according to claim 3,
Furthermore, when the number of times of writing for each attribute exceeds the upper limit value of the number of times of writing set for this attribute, it is provided with a write prohibiting means for prohibiting writing of the parameter of this attribute to the storage element. Measurement control equipment. In the measurement control device according to any one of claims 1 to 4,
A measurement control device characterized in that, for a low change frequency parameter whose change frequency is lower than that of a normal change frequency parameter, a write frequency upper limit value smaller than the write frequency upper limit value for the normal change frequency parameter is preset. A storage element for storing parameters used in the measurement control device;
Write detection means for detecting writing of parameters to the storage element using a communication function from an external device;
A measurement control device comprising: notification means for notifying a user that writing to a storage element using a communication function has been performed when the writing is detected. In the measurement control device according to claim 6,
Furthermore, it comprises parameter registration means for pre-registering a low change frequency parameter whose change frequency is lower than that of the normal change frequency parameter,
When the parameter to be written is a normal change frequency parameter, the notifying means notifies the user only for a first notification time defined in advance for the normal change frequency parameter, and the write target parameter Is a low change frequency parameter registered in the parameter registration means, the user is notified for a second notification time that is defined in advance longer than the first notification time. Control equipment. Write detection procedure for counting the number of times of writing this parameter for each parameter when the parameter is written to the storage element that stores the parameter used in the measurement control device,
Compare the number of writes for each parameter with a preset upper limit of the number of writes for each parameter, and issue an alarm if the number of writes of at least one parameter exceeds the upper limit of the number of writes set for this parameter. A storage element protection method comprising: an alarm generation procedure for issuing a warning. Write detection procedure for counting the number of times of writing of this parameter for each attribute of the parameter when the parameter is written to the storage element storing the parameter used in the measurement control device,
The write count for each attribute of the parameter is compared with a preset write count upper limit value for each parameter attribute, and the write count of at least one attribute exceeds the write count upper limit value set for this attribute. A storage element protection method comprising: an alarm generation procedure for generating an alarm in case. A write detection procedure for detecting this writing when a parameter is written using a communication function from an external device to a storage element that stores a parameter used in the measurement control device;
A storage element protection method comprising: a notification procedure for notifying a user that writing to a storage element using a communication function has been performed when the writing is detected. The memory element protection method according to claim 10.
In the notification procedure, when the parameter to be written is a normal change frequency parameter, the user is notified for the first notification time defined in advance for the normal change frequency parameter. Is a low change frequency parameter whose change frequency is lower than that of the normal change frequency parameter, the user is notified for a predetermined second notification time longer than the first notification time. A storage element protection method.

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