JP2002091520A - Programmable controller and memory module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To store plural programs and pieces of data for sequence control under simple structure with enhanced cost performance in a programmable controller. SOLUTION: The programmable controller is constituted so that the plural programs and pieces of data for sequence control are stored inside a memory module provided independently of a CPU module, the pieces of data in the memory module are transmitted to the CPU module based on a request from the CPU module and the CPU module is made to rewrite a program.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a programmable controller, and more particularly to a technique for storing a sequence control program and data.

[0002]

2. Description of the Related Art FIGS. 3, 4 and 5 show an example of the prior art. FIG. 3 shows a configuration example of a conventional programmable controller provided with a personal computer or the like having a magnetic disk therein as a peripheral device, and FIG. 4 shows a memory map thereof. In FIG. 3, 1 is a CPU module,
2 is a calculation unit, 3 is a RAM as a user memory, 10 is a peripheral device, 11 is a ROM as a system memory, 12
Is an input / output interface, and 13 is an internal bus. In FIG. 4, reference numeral 14 denotes a magnetic disk in the peripheral device 10. In a programmable controller, R
The OM (system memory) 11 has a system program, and the RAM (user memory) 3 has, for example, a ladder program as a sequence control program of the user. The RAM 3 is divided into a user program memory section and a running memory section. The created ladder program as a sequence control program is written in the user program memory unit. After that, the ladder program is converted into an object and developed in the running memory unit. The execution of the program is performed by executing the expanded contents of the running memory in the arithmetic unit 2. Since only one ladder program can be written in the RAM 3 of the user memory, a plurality of ladder programs are stored on the magnetic disk 14 in the peripheral device 10 such as a personal computer. Therefore, CP
The rewriting of the program of the U module 1 is performed by transferring the ladder program of the magnetic disk 14 in the peripheral device 10 such as a personal computer to the CPU module 1 by operating the operator. In the CPU module 1,
The ladder program received from the magnetic disk 14 via the input / output interface 12 is transferred to a user program memory in the RAM 3 as a user memory, and is rewritten in the user program memory. At this time,
If the CPU module 1 is in a stopped state, object development is performed immediately. If the CPU module 1 is in a running state, object development is performed at the end of one scan.

FIG. 5 shows a configuration example of a conventional programmable controller provided with a disk module having a magnetic disk separately from peripheral devices. In FIG. 5, 15 is a disk module, and 16 is a magnetic disk in the disk module. In the conventional technique shown in FIG. 5, a plurality of ladder programs as sequence control programs are stored in a magnetic disk 16 in the disk module 15.

[0004]

In the conventional programmable controller shown in FIGS. 3 to 5, in order to enable storage of a plurality of sequence control programs, a plurality of user memories 3 are used, or It is necessary to separately provide a disk module 15 having a storage medium such as a magnetic disk, and to read / write the program by directly accessing it under centralized control by an arithmetic unit in the CPU module. However, in such a case, it is expected that the cost performance of the operation unit dedicated as the control device cannot be improved, and that the scale of the system software becomes large and complicated. The problem of the present invention is that (1) a plurality of sequence control programs and data can be stored,
(2) Cost performance can be improved, (3)
That is, the CPU module is not a storage device to be directly accessed, and (4) it has a simple configuration. An object of the present invention is to provide a programmable controller that can solve the above problems.

[0005]

In order to solve the above-mentioned problems, the present invention provides: (1) In a programmable controller having a CPU module, a plurality of CPUs for sequence control are provided in an internal memory unit independently of the CPU module. Having a memory module capable of storing various programs and data,
The program and data in the memory module are sent to the CPU module based on a request from a user program of the module, and the CPU module rewrites the program. (2) In a programmable controller having a CPU module, a memory module connected to the CPU module, the input / output interface unit for connection, a communication unit capable of communicating with a peripheral device, and a transmission from the peripheral device. A shared memory unit that can store a plurality of programs and data for sequence control, and a control unit that extracts signals from the shared memory unit and communicates with the arithmetic unit of the CPU module. In response to the request, the program and data in the shared memory unit are transmitted to the CPU module, thereby causing the CPU module to rewrite the program. (3) In the above (1) or (2), the program for sequence control is a program in which a development connection diagram of a circuit for sequence control is configured in a ladder diagram system. (4) In the above (2), a configuration is provided in which a plurality of the CPU modules are provided and can be mounted in an arbitrary slot. (5) a memory module for a programmable controller, having a configuration independent of a CPU module;
A plurality of programs and data for sequence control can be stored in an internal memory unit, and the programs and data are sent to the CPU module based on a request from a user program of the CPU module to cause the CPU module to rewrite the program. The configuration is as described above. (6) A memory module for a programmable controller, an input / output interface unit for connection to a CPU module, a communication unit capable of communicating with a peripheral device, and a plurality of programs for sequence control transmitted from the peripheral device. A shared memory unit capable of storing data; and a control unit that extracts a signal from the shared memory unit and communicates with the arithmetic unit of the CPU module. Is transmitted to the CPU module to cause the CPU module to rewrite the program. (7) In the above (5) or (6), the sequence control program is a program in which a development connection diagram of a sequence control circuit is configured in a ladder diagram system.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows an embodiment of the present invention. In FIG. 1, 1 is a CPU module, 2 is an operation unit, 3 is a user memory, 4 is a memory module, 5
Is a control unit, 6 is a shared memory, 7 is an input / output interface, 8 is a communication unit, 9 is a bus, and 10 is a peripheral device. The communication unit 8 communicates with the peripheral device 10. The shared memory 6
The program sent from the peripheral device 10 is stored. The input / output interface 7 is connected to the CPU module 1 via the bus 9 and communicates with the CPU module 1. The control unit 5 interprets and executes a data transfer request command from the CPU module 1, a data transfer command to the CPU module 1, a program reception command from the peripheral device 10, and management of the shared memory 6. And do. The memory module 4 stores the user memory 3 of the CPU module 1.
Based on a program rewrite request command from a ladder program as a sequence control program in the CPU, the corresponding program and data in the shared memory are transmitted to the CPU module to cause the CPU module to rewrite the program by changing during RUN. The program rewrite in the user memory 3 of the CPU module 1 supports a program rewrite request command.

FIG. 2 shows a memory map of the shared memory 6. The CPU module executes a program (program A) in the user memory 3. If there is a dedicated instruction (program B) during execution, the CPU module transfers the instruction to the memory module 4 as it is. The memory module 4 receives the dedicated command via the control unit 5, interprets the content as a program transfer request, and proceeds to execution. The control unit 5 reads the corresponding program from the beginning, and sends a request for change during RUN, which is a user memory rewrite instruction of the CPU module, to the CPU module with the read program attached. The RU
The instruction of change during N is a program rewriting instruction and is transmitted from a peripheral device such as a personal computer. The memory module 4 also supports the RUN change instruction.

[0008] The dedicated instruction for rewriting the program includes data of the mounting slot, the program name, and the data name. The operation unit 2 of the CPU module 1 interprets the command and transmits the dedicated command to the corresponding shared memory module from the information of the mounting slot. Accordingly, even if a plurality of memory modules are provided and mounted in an arbitrary slot, it is possible to cope with the problem. The dedicated instruction is transmitted via the bus 9. The input / output interface 7 of the shared memory module 4 inputs and outputs information to and from the CPU module 1 and passes information to the control unit 5. The control unit 5 interprets and executes the instruction, and determines that the program transfer to the CPU module 1 is necessary from the program rewriting instruction of the operation code and the program name and data name of the operand. For the transfer of the program, a change during RUN command is used, and the program and data are added to the change during RUN command and transferred to the CPU module. The control unit 5 manages the names of programs and data and their addresses as a map, and updates the contents when accessing the CPU module at the time of transmission or saving from the peripheral device.

When the arithmetic unit 5 of the CPU module 1 receives the change during RUN from the memory module, it performs the same process as the conventional change during RUN from the peripheral device 10. That is, the received ladder program and data are stored in the user program memory section of the user memory 3, and the scan is interrupted at the end of the program scan. Next, the ladder program in the user program memory unit is developed into an object, stored in the running memory unit, and the scan is restarted, whereby the program in the running memory unit is executed.

FIG. 6 shows a processing flow according to the configuration using the memory module 4. FIG. 6A shows the processing in the user memory shown in FIG. 2 in the processing in the CPU module, and FIG. 6B shows the processing when the control unit 5 in the memory module 4 receives the dedicated command. Flow, FIG.
(C) is a processing flow when the control unit 5 in the memory module 4 reads the program to be transferred and transfers the read program together with the RUN change command. FIG. 6D shows the flow of the RUN change during program rewriting, which is a process in the CPU module. The RUN change instruction + user program data sent from the memory module 4 follows this flow. It is processed and the program is rewritten.

According to the above embodiment, the CPU module only newly supports a dedicated instruction for a program rewrite request, and there is no need for an independent memory module to directly access or manage the shared memory. Conventionally, only one sequence control program can be placed on a programmable controller. However, by providing a memory module, a plurality of sequence control programs such as a ladder program can be stored. The rewriting of the program of the CPU module is performed by the operator from the peripheral device, but the program can be automatically rewritten from the memory module by executing the dedicated instruction of the sequence control program. Further, since the program can be rewritten from a sequence control program such as a ladder program, if the program is executed while rewriting the program sequentially, a larger program can be executed without being restricted by the physical capacity of the user memory. . Further, each memory can be selectively used for executing a program, for example, a high-speed and expensive small-capacity memory is used for a user memory, and an inexpensive and low-medium-speed large-capacity memory is used for a shared memory. Since a plurality of independent memory modules can be mounted on the programmable controller, the storage of the sequence control program can be flexibly handled in terms of capacity. Further, by providing the control unit, it is possible to communicate with the CPU module while being a module.

[0012]

According to the present invention, a plurality of sequence control programs and data can be stored in the programmable controller with a simple configuration, and the program of the CPU module can be automatically rewritten.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing an example of a memory map according to the present invention.

FIG. 3 is a diagram showing an example of the related art.

FIG. 4 is a diagram showing a memory map of a conventional program transfer.

FIG. 5 is a diagram showing an example of the related art.

FIG. 6 is a diagram showing a flow of a program rewriting process by a memory module according to the present invention.

[Explanation of symbols]

1 ... CPU module, 2 ... Calculation unit, 3 ... RAM,
4: memory module, 5: control unit, 6: shared memory, 7, 12: input / output interface, 8: communication unit, 9: bus, 10: peripheral device, 11: ROM,
12: input / output interface, 13: internal bus,
14, 16: magnetic disk, 15: disk module.

Continuation of the front page F term (reference) 5H215 BB10 BB16 CC09 CX04 GG04 HH01 HH03 5H220 BB12 BB17 CC09 CX04 DD04 EE01 EE08 FF03 FF05 JJ12 JJ24

Claims (7)

[Claims] 1. A programmable controller having a CPU module, comprising: a memory module capable of storing a plurality of programs and data for sequence control in an internal memory unit independent of the CPU module; A programmable controller characterized in that the program and data in the memory module are sent to the CPU module based on a request from the program, and the CPU module rewrites the program. 2. A programmable controller having a CPU module, wherein the memory module is connected to the CPU module, the input / output interface unit for connection, a communication unit capable of communicating with a peripheral device, and the peripheral device. A shared memory unit capable of storing a plurality of programs and data for sequence control sent from the CPU module; and a control unit that extracts a signal from the shared memory unit and communicates with a calculation unit of the CPU module. By transmitting the program and data in the shared memory unit to the CPU module based on a request from the program,
A programmable controller having a memory module configured to cause a U module to rewrite a program. 3. The programmable controller according to claim 1, wherein the sequence control program is a program in which a development connection diagram of a sequence control circuit is configured in a ladder diagram system. 4. The programmable controller according to claim 2, wherein a plurality of said CPU modules are provided and can be mounted in an arbitrary slot. 5. A memory module for a programmable controller, having a configuration independent of a CPU module, capable of storing a plurality of programs and data for sequence control in an internal memory unit, and a user program of the CPU module. A memory module characterized in that the program or data is sent to the CPU module based on a request from the CPU module to cause the CPU module to rewrite the program. 6. A memory module for a programmable controller, comprising: an input / output interface unit for connection to a CPU module; a communication unit capable of communicating with a peripheral device; and a plurality of sequence control units sent from the peripheral device. A shared memory unit that can store programs and data; and a control unit that extracts a signal from the shared memory unit and communicates with a calculation unit of the CPU module. Transmitting the programs and data in the memory unit to the CPU module,
A memory module characterized by having a module rewrite a program. 7. The memory module according to claim 5, wherein the sequence control program is a program in which a development connection diagram of a sequence control circuit is configured in a ladder diagram system.