JP5338528B2 - Programmable controller and application program update method - Google Patents

Description

  The present invention relates to an online update technique of an application program in a controller system such as a programmable controller.

There is a technique for updating an application program online in a controller system such as a programmable controller. This technique will be described below.
FIG. 4 is a block diagram illustrating a first prior art controller system. Processing in the first controller system will be described with reference to FIGS.

  As shown in FIG. 4, the controller system 100 includes a microprocessor 101 and a memory 102. In the memory 102, various data such as an application program area 104, an application data area 105, a system program area 106, and an application location registration table 107 are stored.

  The application program area 104 is generally a storage area for a plurality of application programs. The application data area 105 is a storage area for various parameters used by each application program during execution. The system program area 106 is a storage area for various programs that execute system processing such as application program update (download) processing. The update processing system program is also provided with a determination function for checking the number of update target programs and the like and determining whether the update process is within a specified time.

  As shown in FIG. 5, the application location registration table 107 stores pointers (start addresses) of the application programs stored in the application program area 104. In FIG. 5, the pointers of the programs A and B stored in the application program area 104 are stored in the application location registration table 107.

  The controller system 100 in FIG. 4 cyclically executes each application program stored in the application program area 104 and each system program corresponding to a system process such as download stored in the system program area 106 ( Repeat periodically).

  When executing the application program, the microprocessor 101 recognizes the storage location of each application program in the application program area 104 through the application location registration table 107 and reads each instruction of the target application program into the calculation unit 103. Run.

  When executing the system program, the microprocessor 101 reads each instruction or the like of the target system program (such as update processing) from the system program area 106 and executes it.

  FIG. 6 is a flowchart of application program update processing in the first prior art controller system. This online update processing is executed by an update processing system program (not shown) when an application program is downloaded from a support tool (not shown).

  In FIG. 6, the downloaded application program is stored in the application program area 104 in step S11, and the system program is detected by detecting that the execution period of the application program has ended (end of application program) in step S12. The start of the execution period is determined. In step S13, the pointer of the application location registration table 107 is rewritten to switch from the old application program to the new application program, and the series of processes is completed.

  FIG. 7 is a diagram showing the application program area 104 and the application location registration table 107 after the update in the state of FIG. Here, it is assumed that the program B is updated to the program C by the update instruction. By storing the program C in the free area of the application program area 104 and rewriting the pointer of the program B so as to indicate the head position of the program C at the end timing of the application program, the program C is replaced with the program C. Will be executed.

FIG. 8 shows an execution example of the controller system of the first prior art.
In the example of FIG. 8, the program A and the program B are executed as application programs within one program execution period, and the system is in each idle time between the execution period of one application program and the execution period of the next application program. As the process (application program online update process), a case where each process such as a program storage process and an application location registration table update process is divided and performed is shown.

Next, a second prior art controller system shown in Non-Patent Document 1 will be described.
FIG. 9 is a block diagram showing a second prior art controller system.

  In the second prior art controller system 110 shown in FIG. 9, a cache memory (L2 cache) 111 is added to the first prior art controller system 100 shown in FIG. In order to increase the execution speed and reduce the execution time, the programs A and B stored in the application program area 104 are executed while being stored in the L2 cache 111.

  When the program B in the L2 cache memory space is updated to the program C by the online update process shown in the flowchart of FIG. 6 from the state of FIG. 9 (when the program B is switched to the program C), depending on the size of the program C, Since the program C may overflow from the L2 cache memory, the program C is stored in the non-L2 cache memory space, for example, the application program area 104 in the memory 102, instead of the L2 cache memory. Therefore, when the application location registration table 107 is updated after the download of the update program and the program C is executed for the first time, it is necessary to store the program C in the cache memory 111. The program becomes longer and the periodicity of the program execution period cannot be maintained, causing a problem that the system operation is hindered.

  FIG. 10 is a flowchart of an application program update process in the second prior art controller system. This online update processing is executed by an update processing system program (not shown) when an application program is downloaded from a support tool (not shown). Each step of this flowchart is executed intermittently in the idle time during the execution period of the application program, that is, whenever the end of the execution period of the application program (end of the application program) is detected.

  In FIG. 10, the downloaded application program (also referred to as “AppProg”) is stored in the application program area 104 (also referred to as “external memory” because it is outside the microprocessor 101) in step S21. . That is, the existing application program stored before the online update included in the update instruction is subjected to processing such as deletion and overwriting according to the contents of the update (deletion, re-storing (overwriting)). Thereafter, the newly added application program included in the update instruction is stored in the free area of the application program area 104.

  In step S22, it is determined whether the cache memory 111 is subject to change (overwriting) according to the current update instruction or whether there is a program to be deleted. Application programs that are determined to exist and are subject to processing such as deletion and overwriting this time are deleted from the cache memory 111. Then, as a storage location search process of the cache memory 111, an empty area is searched, and an existing application program to be updated (changed) this time or an application program newly added this time are stored in the searched empty area.

  In step S23, the pointer of the application location registration table 107 is rewritten to switch from the old application program to the new application program, and the series of processes ends.

  As described above, in the second prior art, the application program to be updated is temporarily stored in the external memory 104 which is a non-cache space by online update, and the application program is cached at the end timing of the application program, for example. 111, the application location registration table 107 is updated, and the update application program is executed. Thus, the execution time is stabilized by always executing the application program in the cache memory 111.

However, in general, the online update process is often performed for each application program, and if the number of update application programs increases, there is a problem that the following three times increase.
1. 1. Time required to search the cache memory 111 for the storage location of the update application program 2. Time to delete the old application program before update from the cache memory 111 Time required to store the update application program in the cache memory 111 As a result, as shown in FIG. 11, the next application program is not completed within the system management time starting from the end timing of the application program. There is a possibility that the online update process will be executed beyond the execution start time. When such time extension of the online update process is performed, the execution start time of the next application program is delayed, or, in the case of a system that places importance on constant periodicity, the execution cycle of the application program is lost. For this reason, the timeliness of the online update process execution time cannot be maintained before and after downloading the application program.

  In addition, as a peripheral technology, Patent Document 1 discloses a file storage device. In this file storage device, when updating the contents of a plurality of blocks of a disk in which management information, file data, etc. are stored, a temporary storage area is provided on the disk and data is written to the temporary storage area. At that time, after data is stored in a continuous temporary storage area on a temporary memory different from that of the disk, writing to the temporary storage area on the disk at a time eliminates the need for writing for each block, and the number of accesses to the disk. To reduce the time required for writing.

JP-A-6-139123

Japan Society for Invention and Innovation Open Technical Report No. 2008-501640

  The present invention has been made in consideration of the above-described problems, and even when the number of application programs to be updated increases, it is possible to maintain the periodicity of the program execution period in the system operation. An object of the present invention is to provide a method for updating a controller and an application program.

  The proposed programmable controller includes first and second memories that store application programs, a processing device, and a calculation unit, and the processing device includes a priority order of the first memory and the second memory. Is a programmable controller that reads and executes the application program into the arithmetic unit and receives an update instruction of the application program at a fixed cycle timing, and stores the application program without the update instruction stored in the first memory. Non-update program storage location specifying means for searching on the second memory to specify the storage location, an application program updated this time according to the update instruction stored in the second memory, and a new addition this time Identify the application program and the storage location Relocation means for relocating non-updated application programs on the second memory so that addresses are continuous, and invalidating all application programs stored in the first memory at the fixed cycle timing And storing means for storing the rearranged continuous application programs in the first memory at a timing next to the fixed period.

  In the proposed programmable controller, the application program to be updated (changed or newly added) and the application program not to be updated are rearranged on the second memory so that the addresses are continuous. Thereafter, the first memory is invalidated, and all the continuous program groups rearranged on the second memory are stored in the first memory.

  For this reason, a storage location search process for storing an application program in the first memory as in the prior art, and a determination process for determining whether a program that is to be changed / deleted by the current update instruction exists in the first memory. Can be eliminated. Since the time required for these increases as the number of application programs increases, the time required for the storage processing in the first memory as part of the update processing can be shortened.

  Therefore, it is possible to avoid the fact that the fixedness of the execution time before and after the online update cannot be maintained due to the extension of the storage process to the first memory, and the number of application programs to be updated increases. However, it can maintain the regularity of system operation.

It is a block diagram which shows the controller system of this embodiment. It is a flowchart of the update process of the application program in the controller system of this embodiment. It is the figure which compared and showed operation | movement of the controller system of the 2nd prior art with respect to a certain update instruction, and the controller system of this embodiment. It is a block diagram which shows the controller system of the 1st prior art. It is the figure which showed the relationship between an application program area | region and an application position registration table. It is a flowchart of the update process of the application program in the controller system of the 1st prior art. FIG. 6 is a diagram showing an application program area and an application location registration table after updating the state of FIG. 5. It is a figure which shows the example of execution of the controller system of a 1st prior art. It is a block diagram which shows the controller system of the 2nd prior art. It is a flowchart of the update process of the application program in the controller system of the 2nd prior art. It is a figure which shows the problem of the controller system of the 2nd prior art.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings. In addition, this application utilizes the said nonpatent literature 1.
FIG. 1 is a block diagram illustrating a controller system according to the first embodiment.

  As shown in FIG. 1, the controller system 10 includes a microprocessor 1 and a memory 2. In the memory 2, various data such as an application program area 4, an application data area 5, a system program area 6, and an application location registration table 7 are stored.

The microprocessor 1 includes a calculation unit 3 and a cache memory 8.
In the following description, an L2 cache (Level2 Cache) is used as a cache memory. However, a CPU (Central Processing Unit) cache (a high-speed small-capacity memory used to fill a performance difference between a processing device and a storage device) ), It is possible to easily increase the capacity and use any cache that can improve the performance of the CPU.

  The application program area 4 is generally a storage area for a plurality of application programs (in the figure, program A, program B, etc.). The application data area 5 is a storage area for various parameters used by each application program during execution. The system program area 6 is a storage area for various programs that execute system processing such as application program update (download) processing. The update processing system program is also provided with a determination function for checking the number of update target programs and the like and determining whether the update process is within a specified time.

  Here, the determination function is determined based on the measured value of the memory performance, the number of application program steps (total program capacity), the time that can be allocated for the update process in a fixed period of the controller (see FIG. 10), etc. . For example, when T> 1000 a / m (msec) is satisfied, assuming that the writing speed to the memory m (byte / sec), the specified time is T (msec), and the total capacity of the application program to be updated is a (byte). Is determined to be within the specified time. Actually, there are factors such as the time taken for the determination itself, but it can be regarded as being sufficiently smaller than the memory writing speed, and a value smaller than T may be used as the threshold value.

  The application location registration table 7 stores pointers (head addresses) of the application programs stored in the application program area 4. For example, pointers of programs A and B stored in the application program area 4 are stored in the application location registration table 7.

  The controller system 10 of FIG. 1 cyclically executes each application program stored in the application program area 4 and each system program corresponding to a system process such as download stored in the system program area 6 ( Repeat periodically).

  When executing the application program, the microprocessor 1 recognizes the storage position of each application program on the application program area 4 through the application position registration table 7 and reads each instruction of the target application program into the calculation unit 3. Run. Note that application programs that are frequently used are normally stored in the cache memory 8, and are read into the calculation unit 3 and executed from there.

  When executing the system program, the microprocessor 1 reads each instruction and the like of the target system program (such as update processing) from the system program area 6 and executes it.

  FIG. 2 is a flowchart of application program update processing in the controller system of this embodiment. This online update processing is executed by an update processing system program (not shown) when an application program is downloaded from a support tool (not shown). Each step of this flowchart is executed intermittently in the idle time during the execution period of the application program, that is, whenever the end of the execution period of the application program (end of the application program) is detected.

  In FIG. 2, the downloaded application program (sometimes referred to as “AppProg”) is stored in the application program area (also referred to as “external memory” because it is outside the microprocessor 1) 4 in step S <b> 1. . That is, overwriting or the like is performed on the existing application program stored before the online update included in the update instruction according to the update contents (restore).

Then, the newly added application program included in the update instruction is stored in the free area of the application program area 4.
Further, the entire search is performed on the external memory 4 to find an application program (an application program that is not updated and remains in the cache memory 8) that is stored in the cache memory 8 and is not updated by the current update instruction.

  Then, the addresses of the application program that has been re-stored (overwritten), the application program that has been found by the search process for the external memory 4 and remains in the cache memory without being updated, and the application program to be newly added are consecutive on the external memory 4. Rearrange (by copying etc.) Then, the copy source application program and the application program designated to be deleted in the update instruction are deleted from the external memory 4.

  The method described above is merely an example, and the addresses may be arranged to be continuous at the time of storing a newly added application program included in the update instruction. In addition, the existing application program stored before online update is not overwritten and updated so that the address of the newly added application program and the address are continuous (at this stage, the new and old application programs coexist).

  Thereafter, a full search is performed on the external memory 4 to find an application program that is stored in the cache memory 8 and is not updated by the current update instruction (an application program that is not updated and remains in the cache memory 8).

  Then, the application program that is found in the search process for the external memory 4 and remains in the cache memory without being updated is arranged so that the address is continuous on the external memory 4 with the application program arranged as a series of consecutive addresses ( Relocate (eg by copying).

  Finally, copy the source application program, the application program specified to be deleted in the update instruction, and the application program remaining as it is not overwritten by the application program specified to be updated in the update instruction. Delete from 4.

In the next step S2, all application programs in the cache memory 8 are invalidated.
In step S3 following step S2, each successive application program (including newly added, changed, and not updated this time) rearranged on the external memory 4 is stored in the cache memory 8.

  In step S4, the pointer in the application location registration table 7 is rewritten to switch from the old application program to the new application program, and the series of processing ends.

FIG. 3 is a diagram comparing the operation of the controller system of the second prior art and the controller system of the present embodiment with respect to a certain update instruction.
Here, the controller system according to the second prior art when the controller system 10 receives an update instruction having instructions to delete the application program Prog1, store Prog4, Prog6, Prog10, and store Prog2 again. The operation of the controller system is compared. When the controller system 10 is instructed to update, the external memory 4 stores Prog1, Prog2, Prog3, Prog5, Prog7, Prog8, Prog11, Prog12, Prog13, and the cache memory 8 stores Prog1, Prog2, Prog3 and Prog5 are stored.

  In the controller system of this embodiment, as processing corresponding to step S1 in FIG. 2, Prog4, Prog6, and Prog10 are stored in continuous free areas of the external memory 4, and Prog2 is continuous with Prog4, Prog6, and Prog10. Store again. Then, by searching all over the external memory 4, the programs (Prog3, Prog5) stored in the cache memory 8 and not updated online at this time are found. The found Prog3 and Prog5 are copied in the external memory 4 so that the addresses are continuous with Prog4, Prog6, Prog10 and Prog2, and the copy source area of the copied Prog2, Prog3 and Prog5 is set to the external memory. In addition to deleting from Prog 1, Prog 1 for which a deletion instruction is issued is deleted from the external memory 4. Further, the Prog 2 that has been stored from the original is deleted from the external memory 4 among the Prog 2 that coexist with the old and new by storing again.

In this case, it is assumed that the number of programs included in the update instruction is large and it has been determined that the update time affects the execution cycle.
As processing corresponding to step S2 in FIG. 2, all application programs (Prog1, Prog2, Prog3, Prog5) stored in the cache memory 8 are not deleted, and the entire area of the cache memory 8 is invalidated.

As processing corresponding to step S3 in FIG. 2, Prog2, Prog4, Prog6, Prog10, Prog3, and Prog5 having consecutive addresses are stored in the cache memory 8.
Next, the operation of the second prior art controller system will be described.

  In the second prior art controller system, as processing corresponding to step S21 in FIG. 10, Prog1 in the external memory 4 is deleted, Prog2 is stored again, and Prog4, Prog6, and Prog10 are free areas in the external memory 4. To store.

  Next, as a process corresponding to step S22 in FIG. 10, it is determined whether or not the cache memory 8 has a program to be changed or deleted by the current update instruction. . Then, the previous version of Prog1 for which deletion instruction has been issued and Prog2 changed by the re-storing is deleted from the cache memory 8. Subsequently, as a storage location search process in the cache memory 8, a free area is searched, and an existing application program (Prog2) to be updated (changed) or a newly added application program (Prog4, Prog6, Prog10) is searched. Store in the free space.

  As described above, in this embodiment, the application program to be updated (changed or newly added) and the application program already stored in the cache memory 8 and not updated online are rearranged so that the addresses are continuous on the external memory 4. The cache memory 8 is invalidated and all the continuous program groups rearranged from the external memory 4 are stored in the cache memory 8.

  For this reason, when the number of application programs to be updated increases, it takes a long time, the storage location search process when storing the application program in the cache memory 8, whether the current update instruction is the target of change, Alternatively, it is possible to eliminate the process of determining whether or not the program to be deleted exists in the cache memory 8, and to reduce the time required for the storage process in the cache memory 8 as a part of the online update process.

  Therefore, it is possible to avoid the fact that the fixed time of the execution time before and after the online update cannot be maintained as the storage process in the cache memory 8 is extended, and the number of application programs to be updated increases. However, it can maintain the regularity of system operation.

DESCRIPTION OF SYMBOLS 1,101 Microprocessor 2,102 Memory 3,103 Operation part 4,104 Application program area 5,105 Application data area 6,106 System program area 7,107 Application location registration table 8,111 Cache memory 10,100,110 Controller system

Claims (4)

First and second memories for storing application programs, a processing device, and a calculation unit, wherein the processing device stores the application programs in the priority order of the first memory and the second memory. In a programmable controller that reads / executes to the arithmetic unit and receives an update instruction of the application program at a fixed cycle timing,
Non-update program storage location specifying means for searching the second memory for an application program without the update instruction stored in the first memory and specifying a storage location;
An application program that is updated this time in response to the update instruction stored in the second memory, an application program that is newly added this time, and an application program that is not updated and that specifies the storage location. In the above, rearrangement means for rearranging so that the addresses are continuous,
All application programs stored in the first memory at the fixed cycle timing are invalidated, and the rearranged continuous application programs are stored in the first memory at the next timing of the fixed cycle. And a storage means. According to the number of application programs included in the update instruction, further includes a determination unit that determines whether or not the update process falls within the fixed period,
2. The non-update program storage location specifying unit, the rearrangement unit, and the storage unit are executed when it is determined by the determination unit that the update process does not fall within a specified time. Programmable controller.   The programmable controller according to claim 1 or 2, wherein the content of the update instruction is a new addition of an application program, a change of an existing program, or a deletion. First and second memories for storing application programs, a processing device, and a calculation unit, wherein the processing device stores the application programs in the priority order of the first memory and the second memory. In the update method of the application program executed by the programmable controller that reads / executes to the calculation unit and receives the update instruction of the application program at a fixed cycle timing,
Searching the second memory for an application program stored in the first memory without the update instruction and specifying a storage location;
The application program stored in the second memory that is updated this time, the application program that is newly added this time, and the application program that is not updated and that specifies the storage location are continuously addressed on the second memory. A step of rearranging and
All application programs stored in the first memory at the fixed cycle timing are invalidated, and the rearranged continuous application programs are stored in the first memory at the next timing of the fixed cycle. And a method for updating an application program.