JPH0736370A - Data transmitting and receiving system, and method therefor - Google Patents

Abstract

PURPOSE:To realize an efficient communication without having an influence on the sequence control of a programmable controller, and realize the shortening of waiting time in the multitask processing of a FA controller. CONSTITUTION:A data transmitting and receiving system is provided with a common memory device 70 formed of plural sets of a request area 11-i (hereinafter i=1-N) and a response area 12-i, and a control area 10-i for controlling the size of the request area 11-i and the response area 12-i every set in such a manner that the length can be varied; a FA controller 1 for setting the data size of the request area 11-i and the response area 12-i, and setting a request data in the request area 11-i; and a programmable controller 2 for reading the request data of the FA controller 1, executing a prescribed processing, writing the response data in the response area 12-i, and replying to the FA controller 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data processing between a FA controller and a programmable controller, a management area for managing the size and usage of a request area and a response area, and a request area based on each information of the management area. The present invention relates to a data transfer system and method for efficiently transferring data using a common storage device that manages a response area.

[0002]

2. Description of the Related Art In a production line in which a product (work) flows on a belt conveyor, a plurality of programmable controllers are installed in the equipment to perform machine control and counting of parts. These programmable controllers are connected by a network, exchange data with each other in real time, and control the entire line. Sending and receiving data in real time is an indispensable function in a production line.If data cannot be sent and received in real time, for example, even if a certain component is out of stock, the flow of work does not stop, An unfavorable situation occurs in which the product flows to the next process in the state of being out of stock.

The FA controller controls the network composed of the programmable controller as described above, and controls the production line processes and monitors the facilities. For example, based on the setup information, a sequence program is downloaded to each programmable controller, production information, failure information, etc. are collected from each programmable controller, and control such as synchronization among a plurality of programmable controllers is executed. As described above, the FA controller needs to constantly monitor the data of each programmable controller and quickly respond to a change in the work process or a machine failure. In addition, data is exchanged between the FA controller and the programmable controller with high communication frequency and high speed.

In response to such a request, conventionally, as one of the methods of exchanging data between the FA controller and the programmable controller, the programmable controller is made into a board and an optional slot (external bus slot) of the FA controller is provided. A method of attaching to the is known. In this system, the interface between the FA controller and the programmable controller is executed via the shared storage device on the programmable controller. Programmable controller
It is connected to a plurality of other programmable controllers via a network and executes a sequence program while exchanging data with each programmable controller. The FA controller may access the data of the programmable controller on the network possessed by the programmable controller or may directly access the data of the programmable controller via the network.

When the FA controller exchanges data with the programmable controller, the FA controller outputs a request for data exchange, and the programmable controller responds to the request. For example, when data is transmitted from the FA controller to the programmable controller, the FA controller outputs a data writing request, so a code indicating writing, the start address of the writing destination, the number of writing data, and the writing data. When the data composed of is transmitted, the programmable controller returns data indicating the write confirmation. Further, when the FA controller reads data from the programmable controller, the FA controller sends data including a read code, a read start address, and a read number, and the programmable controller returns read data as a response. .

As described above, in the data transfer processing between the FA controller and the programmable controller, the data transfer in which the request and the response are one set is executed. Conventionally, a request area and a response area are provided on the shared storage device and used for the request and the response, respectively. However, in the conventional request area and response area, the size on the shared storage device is fixed, and the data that can be transmitted and received in one communication is naturally determined. Further, since the data to be handled when transmitting the data transfer request is specified only by the start address and the number of data, the data that can be transferred in one communication is only the continuous address.

Next, the above conventional example will be specifically described. FIG. 12 is a block diagram showing the entire conventional system, and shows a method of exchanging data between a conventional FA controller and a programmable controller. In the figure, the present system mainly comprises an FA controller 1 that executes multitasking processing, and a programmable controller 20 that executes predetermined processing based on a sequence program.

The FA controller 1 comprises a CPU 3 for the FA controller 1 and a main storage device 4 for the FA controller 1. The programmable controller 2 includes a main storage device 5 for the programmable controller 2, a CPU 6 for executing sequence program processing of the programmable controller 2, and a shared storage device 7. Further, the shared storage device 7 is
Both the CPU 3 for the FA controller 1 and the CPU 6 for the programmable controller 20 are connected so as to be accessible.

Further, the shared storage device 7 has a request area 9 for setting request data when the FA controller 1 outputs a request to the programmable controller 20.
0, the programmable controller 20 receives a request from the FA controller 1, and sets a response area 91 for setting response data, and a handshake flag for notifying the presence or absence of a request or response between the FA controller 1 and the programmable controller 20. A handshake flag storage area 92 for storing is prepared. The address and size of the request area 90 and the response area 91 in the shared storage device 70 are fixed.

Next, the operation will be described. When exchanging data between the FA controller 1 and the programmable controller 20, first, the CPU 3 for the FA controller 1 writes the request data in the request area 90 indicated by the fixed address in the shared storage device 7, and then the handshake flag. A value indicating "requested" is set in the storage area 92. The CPU 6 for the programmable controller 20 regularly monitors the handshake flag storage area 92, and when "requested" is detected, the requested data is read from the requested area 90 and the processing for the request is executed. Then, the response data is written in the response area 91 indicated by the fixed address in the shared storage device 7, and the value indicating “response is present” is set in the handshake flag storage area 92. C for FA controller 1
When PU3 receives this "response", the response area 9
Read response data from 1.

In addition to the above-mentioned conventional example, there is a "communication system using a shared memory" disclosed in Japanese Patent Laid-Open No. 210310/1983 as a conventional technique related to the present invention. This is a communication method aiming to improve the efficiency of communication between a plurality of CPUs, in which a memory in a shared storage device is dynamically secured as necessary and allocated as a communication buffer. In this method, a memory required when transmission is necessary is secured, the transmission data is written in the secured memory, a communication ID for pointing the destination is set, and an interruption is made to the receiving CPU. Generate. The receiving side receiving the interrupt reads the transmitted data, and then returns the data indicating the reception confirmation to the transmission source in the same manner as at the time of transmission.

[0012] In addition, as a reference technical document related to the present invention, "memory control method in operating system" disclosed in Japanese Patent Laid-Open No. 3-105441 and "Programmable Programmable" disclosed in Japanese Patent Laid-Open No. 3-127104. There is a controller data link device.

[0013]

However, in the conventional data transfer system as described above, the address and size in the shared storage device of the request area and the response area are fixed, so When writing a large amount of data to the programmable controller, when a large amount of request area is used, when receiving a programmable controller data into the FA controller, a large amount of data is received, and a large amount of response area is used. In this case, there is a problem in that the memory area of the shared storage device cannot be effectively used according to the writing and reading of data.

Further, the data that can be handled in one data transfer needs to be continuous addresses corresponding to the memory area of the continuous device of the programmable controller. It was necessary to divide and repeat the communication. When data is exchanged in a plurality of times, naturally, there is a problem that the time required for the communication increases and it becomes difficult to control the production line in real time.

For example, when the FA controller monitors the failure information of the machine controlled by each programmable controller, if the data of each programmable controller is not a continuous address, the data is read by the number of programmable controllers in the network. The process has to be repeated. In particular, when a failure occurs in the production line and an emergency stop must be applied, there is a risk that the machine may be broken or an accident may occur due to the delay of the stop.

Further, if the communication is divided into a plurality of pieces, the problem that the situation of the production line changes between the communication occurs. For example, when the FA controller collects data on the number of units produced and the number of remaining parts and creates a form based on the data, the actual data is read when the data is read first and when the data is read last. If the production volume has changed, there is a problem that incorrect data forms are created.

Further, in the FA controller, since it is necessary to constantly monitor the programmable controller as described above, the programmable controller can be programmed even while the form is printed out or communication with the host computer above the FA controller is being executed. Do not interrupt communication with the controller. Therefore, the FA controller
A multitasking function is required to perform other processing while exchanging data with the programmable controller. However, in the conventional data transfer method, only one communication can be used in the request area and the response area, and the request area is not compatible with the multitask processing of the FA controller. However, there is a problem that it is necessary to execute task queuing, and the waiting time becomes long.

[0018] For example, when switching the items to be produced,
When rewriting the sequence program of the programmable controller to the next production item, in the conventional method, it was not possible to monitor the programmable controller in operation by one task and download the sequence program by another task. . Therefore, until all the workpieces on the production line are exhausted, it is necessary to monitor the programmable controller and download the program when all the machines controlled by the programmable controller are stopped, thus improving work efficiency. There was a problem that it was bad.

Further, in the "communication system using a shared memory" disclosed in Japanese Patent Laid-Open No. 2-310664, a process of securing a memory is executed each time communication is performed.
When real-time property is required such as data exchange between the FA controller and the programmable controller, and when communication frequency is high, CPU overhead for searching a free area and securing memory increases. Further, in a communication system in which an interrupt is generated and data is transmitted to a CPU that executes a sequence program, such as a programmable controller, there is a problem that sequence control may be jammed.

The present invention has been made in view of the above, and in the data transfer between the FA controller and the programmable controller, the shared storage device is effectively utilized, and the efficiency is improved without affecting the sequence control of the programmable controller. It is an object of the present invention to provide a data transfer system and method capable of realizing good communication and reducing the waiting time in the FA controller multitask processing.

[0021]

In order to achieve the above object, a data transfer system according to the present invention is provided with a plurality of request areas for storing request data and a plurality of response areas for storing response data. A shared storage means consisting of an area and a management area that manages the size of the response area so that each set can be variable in length, and an FA controller that sets the data size of the request area and the response area and sets the request data in the request area And a programmable controller that reads the request data from the FA controller, executes a predetermined process, writes the response data in the response area, and responds to the FA controller.

Further, the FA controller sets a request code indicating the type of request and a block number indicating the number of request blocks, and transmits / receives the data of the programmable controller.

The management area includes a flag storage area for storing a value for determining the presence or absence of a request and a response, a request area head offset storage area for storing an offset value up to the head address of the request area, and a request area. A requested area length storage area that stores the area length of the area,
It comprises a response area head offset storage area for storing an offset value up to the head address of the response area and a response area length storage area for storing the area length of the response area.

In the management area of the shared storage means,
A next area number storage area is provided for storing the next area number when two or more request areas or response areas are used in one communication.

The data transfer method according to the present invention is
In order to achieve the above object, when writing the request data in the request area, search for an available request area based on the handshake flag of the management area, and request area in the management area according to the size of the request area. The length and the response area start offset are updated, the response area length is updated according to the size of the response data, and data is exchanged between the FA controller and the programmable controller.

[0026]

The data transfer system according to the present invention registers the start address and the size of the request area and the response area in the management area, and when the FA controller and the programmable controller access the request area or the response area, Access is performed based on the address registered in. Also, by registering the start address and size in the management area, the request area and the response area in the shared storage device have variable lengths.

Further, the request code and the number of blocks are set so that various data possessed by the programmable controller can be transmitted and received with respect to the request data in one communication.
The request code indicates the type of request, and the programmable controller reads the data based on this request code,
Processing such as data writing and network information reading is executed. Further, since the number of blocks is to access the data of discontinuous addresses, the data of continuous addresses can be set as one block, and the data of multiple blocks can be designated at one time.

The management area comprises a flag storage area, a request area start offset storage area, a request area length storage area, a response area start offset storage area, and a response area length storage area. Data exchange between the FA controller and the programmable controller is executed based on the data set in the area.

Further, by providing a next area number storage area for storing the next area number when two or more request areas or response areas are used in one communication in the management area of the shared storage device, When the area is large, the area used is expanded and communication is performed using multiple areas.

The data transfer method according to the present invention is
When writing the request data to the request area, search the available request area based on the handshake flag of the management area, and update the request area length and response area start offset in the management area according to the size of the request area. ,
Update the response area length according to the size of the response data,
Data is exchanged between the FA controller and the programmable controller.

[0031]

【Example】

[Embodiment 1] An embodiment of a data transfer system and method according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram showing the configuration of the entire data transfer system according to the present invention. This system is mainly composed of an FA controller 1 that executes multitasking processing and a programmable controller 2 that executes a predetermined processing based on a sequence program. The programmable controller 2 is mounted in an optional slot (external bus slot) of the FA controller 1.

The FA controller 1 comprises a CPU 3 for controlling the FA controller 1 and a main memory 4 of the FA controller 1. The programmable controller 2 includes a CPU 5 that executes the sequence program of the programmable controller 2, a main storage device 6 that stores the sequence program of the programmable controller 2, and a shared storage device 70.

In the shared storage device 70, N sets of management areas, request areas, and response areas are prepared, and one set of areas is used for one communication. . 10-i is a management area (i), 11-i is a request area (i), and 12-i is a response area (i) (i = 1 to N). Note that, for the sake of explanation, the above (i) will be omitted unless misunderstanding occurs.

More specifically, the FA controller 1 executes multitask processing, and a plurality of programs run in parallel on the main storage device 4 of the FA controller 1. On the other hand, in the programmable controller 2, the sequence program is stored in the main storage device 6, and the sequence program is repeatedly read by the CPU 5 that executes the sequence program.

Further, the management area 10 of the shared storage device 70
-I is the request area 11-i and the response area 12 respectively.
-Manage i. The memory of the area managed by the management area 10-i is secured in advance, and it is not necessary to search for a free area or secure the memory during communication. However, the addresses and sizes of the request area 11-i and the response area 12-i are variable in the area managed by the management area 10-i.

FIG. 2 is an explanatory diagram showing a detailed structure of the management area 10-i, and the management area 10-i is assigned with the following areas. That is, 20
Is a handshake flag storage area for storing a handshake flag for determining the presence / absence of a request / response, 21
Is a request area head offset storage area for storing an offset value up to the head address of the request area 11-i, 2
Reference numeral 2 is a request area length storage area for storing the area length of the request area 11-i, 23 is a response area start offset storage area for storing an offset value up to the start address of the response area 12-i, and 24 is a response area 12-i. Is a response area length storage area for storing the area length of.

FIG. 3 is an explanatory diagram showing the data structure of request data and response data when the FA controller 1 reads data from the programmable controller 2. In the figure, 30 is request data and 31 is request type (data Read), 32 is the number of blocks indicating the number of requested blocks, 33 is the start address data indicating the start address of the read data on the programmable controller 2 side, and 34 is the number of read data indicating the number of read data. is there. The head address data 33 and the read data number 34 are repeated by the number of blocks (32). 35 is response data and 36 is read data, and the read data 36 is repeated by the number of blocks (32).

FIG. 4 is an explanatory diagram showing the data structure of request data and response data when the FA controller 1 writes data to the programmable controller 2. In the figure, 40 is request data, 41 is a request code indicating the type of request (data writing), 42 is the number of blocks indicating the number of request blocks, and 43 is the head indicating the start address of the write data on the programmable controller 2 side. Address data, 44 is the number of write data indicating the number of write data. The head address data 43 and the write data number 44 are repeated by the number of blocks (42). Further, 46 is write data, and the number of blocks (4
2) Repeat for minutes. Further, 45 is response data, which is used for confirmation of data reception.

Next, the operation will be described. FIG. 5 shows F
7 is a flowchart showing an operation of communication processing on the A controller 1 side, and FIG. 6 is a flowchart showing an operation of communication processing on the programmable controller 2 side.

In the flow chart shown in FIG. 5, first, the FA controller 1 outputs a request to the programmable controller 2, so the FA controller 1
CPU 3 for use has a request area 11-i and a response area 12
-The memory size required for i is calculated (S50). Note that these memory sizes are calculated based on the data structure shown in FIGS. 3 and 4.

Next, the handshake flag storage area 20 in each management area 10-i is searched to find the management area 10-I in which the value indicating "available" is stored (S51). After that, the request area 1 is added to the request area head offset storage area 21 in the management area 10-I
1-I to the start address, the size of the request area 11-I in the request area length storage area 22, and the response area 1 in the response area start offset value storage area 23
The offset value to the start address of 2-I and the size of the response area 12-I are registered in the response area length storage area 24 (S52).

Next, the CPU 3 for the FA controller 1
Sets the request data in the request area 11-i based on the value of the request area start offset storage area 21 (S53), and sets a value indicating "requested" in the handshake flag storage area 20, that is, the handshake. The flag is set (S54).

Here, the description shifts to the flowchart shown in FIG. In the programmable controller 2, the CPU 5 for the programmable controller that executes the sequence program regularly (every repeated scan of the sequence program) monitors the handshake flag storage area 20 to check whether the handshake flag is “requested” or not. A judgment is made (S60). This step S6
At 0, when "requested" in step S54 is detected, the requested data is read based on the value of the requested area start offset storage area 21 (S61).

Thereafter, the processing according to the request is executed (S
62). In this case, for example, processing such as data reading, data writing, network information collection, and sequence program execution stop is executed. Further, based on the value of the response area head offset storage area 23, response data is written (set) in the response area 12-I.
(S63), a value indicating "responding" is set in the handshake flag storage area 20 (S64).

Next, the explanation will be returned to the flowchart shown in FIG. 5 again. The FA controller 1 side determines whether or not the handshake flag is "response" (S5).
5) If it is determined that there is a response, the response data is read from the response area 12-I based on the value of the response area head offset storage area 23 (S56).
Alternatively, when data is returned from the programmable controller 2 to the FA controller 1, an "interrupt response" may be notified by an interrupt. In this case, in the FA controller 1, the handshake flag storage area 20
Since it does not need to be monitored, other processing can be performed. When the response data is read and the communication is completed, a value indicating "available" is set in the handshake flag storage area 20 (S57).

As is clear from the operation described above,
All access to the request area 11-i and the response area 12-i is executed based on the data in the management area 10-i, and the request area head offset storage area 21 and the request area length in the management area 10-i. The request area 11-i has a variable length by changing the values of the storage area 22, the response area head offset storage area 23, and the response area length storage area 24. Therefore, when a read request is made, the request area 11-i is made small,
The response area 12-i is set to a large value, on the contrary,
When writing is requested, the request area 11-i is set large and the response area 12-i is set small, so that the amount of data handled at one time can be increased.

Further, by adopting an area configuration divided into N as in this embodiment, a plurality of tasks can send requests from the FA controller 1 without waiting time. Multiple communication requests may be output simultaneously from one task. As the operation of the programmable controller 2, the N handshake flag storage areas 20 are regularly monitored, and the processing according to the request is executed for all the areas where "requested" is detected.

Next, again regarding the first embodiment,
This will be described in more detail with reference to FIGS. 7 and 8. FIG. 7 is an explanatory diagram showing a memory state of the shared storage device 70 in the first embodiment. In the figure, the portion indicated by the thick frame corresponds to the request area 11-i + response area 12-i. In the first embodiment, the management area 10-i manages the area. Further, FIG. 8 is an explanatory diagram showing the states of free areas and areas of the shared storage device 70 in the first embodiment.

In the first embodiment, the area (thick frame portion) managed by the management area 10-i has a fixed size. That is, the area managed by the management area 10-i is a fixed area. In this fixed area, the sizes of the request area 11-i and the response area 12-i are variable. For example, when reading data, as shown in FIG. 7A, the request area 11-i is made smaller and the response area 1 is made smaller.
Increase 2-i. On the other hand, when writing data,
On the contrary, the request area 11-i is enlarged and the response area 12 is
-Reduce i.

Further, in the above, the management area 10-i
The area managed by the shared storage device 7 has a fixed length.
This is because there is no need to search for a free area on 0 and secure it. For example, when the area managed by the management area 10-i has a variable length, the shared storage device 70 is composed of areas of various sizes as shown in FIG. Note that in FIG. 8, the request areas 11-i and the response areas 12-i are omitted and the areas managed by the management areas 10-1 to 10-N are simply described as areas 1 to N, for the sake of simplicity.

In FIG. 8A, areas 1 to 4 are all used for data transfer, and the size of each area is determined according to the number of data. Next, as shown in FIG. 8B, the area 2 and the area 4 finish the communication, and the memory is released. Here, when there is a new request for communication that requires the area shown in FIG. 8C, it is necessary to execute any one of the following processes. That is, a search is made for a portion of the free area in which the size required for the next communication can be secured. If such a free area is not found, other communication is terminated and waits until a new sufficient free area is created. A scattered free area (in FIG. 8 (b), area 2 and area 4) Free space) to execute the next communication. In this case, some means for describing the connection relationship between the empty areas is required. As shown in FIG. 8B, when the empty areas are created, the empty areas are packed (used for communication. Shift the area that you are in), always keep empty areas together. In the next communication, the necessary memory is secured from the combined free area and used.

As in the case of communication between the FA controller 1 and the programmable controller 2, when data is exchanged in real time and the communication frequency is high, the above-mentioned
If such a process were executed, the communication time would be rather increased. Therefore, in the first embodiment, the area managed by the management area 10-i has a fixed length, and each area has a uniform size to check whether the area can be used and determine that the area can be used. If it does, it will be immediately available for communication. Whether or not the area can be used is checked only by checking whether or not the value indicating "usable" is included in the handshake flag storage area 20 in the management area 10-i.

The size of the request area 11-i and the size of the response area 12-i are set to be variable so that the memory can be effectively used to the maximum extent in this fixed area. Since the processing for making the request area 11-i and the response area 12-i variable lengths only involves registering the offset address and area size of the area head in the management area 10-i,
It does not affect the communication time.

[Embodiment 2] Next, a second embodiment will be described. In this embodiment, the request area and the response area can be used more effectively by adding the next area number storage area to the management area in the shared storage device 70 in the communication method of the first embodiment.

FIG. 9 is an explanatory diagram showing the detailed structure of the management area 10-i in the second embodiment. In the figure, 80 is a handshake flag storage area, and 81 is 1.
It is a next area number storage area for storing the number of the next area when two or more request areas or response areas are used in one communication. Further, 82 is a required area head offset storage area, 83 is a required length storage area,
Reference numeral 84 is a response area head offset storage area, and 85 is a response area length storage area.

Next, the operation will be described. If the size of the request data or the response data required for communication does not exceed the size of the request area 11-i or the response area 12-i, the communication is executed by the same method as in the first embodiment. You can On the other hand, if the size of the request data or the response data exceeds the size of the request area 11-i or the response area 12-i,
Perform the following processing. Note that, here, a case will be described in which the requested data does not fit in the requested area 11-i.

First, another area number not used for communication is searched (this is set as J), and the searched area number J is stored in the next area number storage area 81 of the management area 10-i. Whether or not the area can be used for communication is determined by whether or not a value indicating "usable" is stored in the handshake flag storage area 80 in the management area 10-i. Next, a value indicating "in use" is written in the handshake flag storage area 80 in the management area 10-i of the searched area, and it is set so that this area cannot be used by other communication. Then, the request data is written from the request area 11-I, and the portion that does not fit in the request area 11-I is written to the request area 11-J.

In the above case, if the data cannot fit in the two areas, the "usable" areas are sequentially searched, and the required data is written using the plurality of areas. When the writing of the request data is completed, a value indicating "requested" is set in the handshake flag storage area 80 in the management area 10-i. The operation after setting the request data is the same as the operation in the case of the first embodiment. Further, in the above description, the case where the request data does not fit in the request area 11-i has been described.
-If i cannot be fully filled, the same process is performed.

Therefore, by executing the communication method as described above, when the amount of data to be communicated is small, the communication is executed using one area on the shared storage device 70, while the amount of data is large. In addition, the area to be used can be expanded and communication can be executed using a plurality of areas. Also in this case, the FA controller 1 is also compatible with multitask processing, and a plurality of tasks can send requests from the FA controller 1 without waiting time.

Next, the second embodiment will be described in more detail with reference to FIG. FIG. 10 is an explanatory diagram showing an area state of the shared storage device in the second embodiment. In the first embodiment described above, an example in which the shared storage device 70 is effectively used while giving importance to real-time property has been described, but the area managed by the management area 10-i (request area 11-i + response area). 12-i) has a fixed length, so when exchanging a large amount of data that cannot be communicated only in this area, it is necessary to execute communication in multiple times (however, normally, it is necessary to execute communication in multiple times). The area is large enough so that there is no need to communicate). Therefore, in order to deal with such a case, in the second embodiment, the next area number storage area 81 (see FIG. 9) is provided in the management area 10-i.

By providing the next area number storage area 81 in the management area 10-i, the areas can be connected and can be exchanged by one-time communication using the method shown in the first embodiment. You will be able to transfer the missing data at once. For example, as shown in FIG.
Consider a case where the portion corresponding to the area 3 is not used for communication and the data is transmitted and received requiring the area shown in FIG. 10B.

In this case, as shown in FIG. 10C, the entire area 1 and a part of the area 3 are used for communication. Management area 10-1 and management area 10- at this time
The contents of 3 are as shown in FIG. A value indicating the area 3 is entered in the next area number storage area 81 of the management area 10-1, the offset value to the beginning of the area 1 is stored in the required area start offset storage area 82, and the required area length storage area 83 is stored in the required area length storage area 83. , The size of area 1 is registered. In addition, the response area top offset storage area 8
4, a value indicating “none”, a response area length storage area 8
“0” is stored in 5.

On the other hand, in the management area 10-3, a flag indicating "in use" is entered in the handshake flag storage area 80, and "none" in the next area number storage area 81.
A value indicating is stored. Then, after the FA controller 1 makes the settings as described above, when a numerical value indicating “requested” is set in the handshake flag storage area 80 of the management area 10-1, the programmable controller 2 firstly manages the management area. By referring to the offset and size of the request area in 10-1, the data in area 1 is read, and further, the request data in the management area 10-3 is read based on the numerical value in the next area number storage area 81. At this time, the next area number storage area 81 is “none”
Therefore, the reading of the requested data is completed, and the requested processing (reading / writing of device data, network information collection, sequence program execution stop, etc.) is executed.

Further, in the above, when returning the response data, first, when the response area start offset storage area 84 of the management area 10-1 is checked, a value indicating "none" is entered. The response area head offset storage 84 of the area 3, which is the next area, is checked. Then, the response data is stored in the response area, and the management area 1
In the 0-1 handshake flag storage area 80, a value indicating "responding" is set. In this embodiment, the method of connecting and using two areas has been described, but a plurality of areas may be connected. Further, both the request area 11-i and the response area 12-i may extend over a plurality of areas.

In addition, in the second embodiment, it is necessary to add the following processing to the processing of the first embodiment. That is, a process of finding an area that is not used for communication when linking areas, a process of storing a next area number and a value indicating "none" in the next area number storage area 81, an area offset and a size are calculated and registered. The process is to refer to the management area 10-i for each area at the time of reading / writing request data and response data, and changing the address to be accessed.

Considering the processing time in the above, it takes a long time to process ,. Therefore,
If a large amount of data that covers a plurality of areas is not handled, the first embodiment can process at higher speed. However, also in the second embodiment, since the method of connecting the areas secured in advance is adopted, it is sufficiently faster than the method of searching for and securing a free area, and data is exchanged in real time. In any case, there is no adverse effect.

Therefore, in multitask processing,
Requests can be output from multiple tasks without waiting. For example, when the sequence program of the programmable controller is rewritten to the next production item at the time of switching the item to be produced on the production line, the sequence program is sent to the programmable controller 2 that has finished the work when the last work passes. It can be downloaded and the setup time can be greatly reduced.

[Third Embodiment] Next, a third embodiment will be described. As a third embodiment of the present invention, a processing method for reading data of the programmable controller 2 from the FA controller 1 by a user program will be described. FIG. 11 is a flowchart showing the operation of the user program for reading the data of the programmable controller 2 from the FA controller 1.

In FIG. 11, first, the number of the management area 10-i for searching the usable area from the N management areas 10-i is set to i, and initialization is performed to set i = 0 (S1). , And i = i + 1 (S2). next,
It is determined whether i> N (S3). If it is determined in step S3 that i> N, the programmable controller 2 is busy (S4), while if it is determined in step S3 that i does not exceed N, management is performed. The handshake flag is read from the handshake flag storage area of area i (S5).

After reading the handshake flag in step S5, it is further determined whether or not the handshake flag is a value indicating "usable" (S).
6). If it is determined in step S6 that the handshake flag is not a value indicating "available",
Returning to step S2, the next management area is checked. As described above, by checking whether or not the management area is available, a plurality of tasks can be executed by the programmable controller 2 in the multitask processing.
Also, it is possible to output a request using an empty area without waiting for the previous request to be completed.

On the other hand, when it is determined in step S6 that the handshake flag has a value indicating "usable", the handshake flag is set to a value indicating "in use" (S7), and another task is set. , Make the area unusable. Then, the data size required for the request is stored in the required area length storage area in the management area (S8). Next, the response area 12-i is the request area 11
The request area start offset + request data size is stored in the response area start offset storage area so as to start from the address next to -i (S9).

Since the sizes of the request area 11-i and the response area 12-i in the management area 10-i can be controlled by the user program in this way, the request area 11-i can be controlled in accordance with the user's request. i and the response area 12-i can be effectively utilized.

Next, after executing step S9, the response data size is stored in the response area length storage area (S1).
0). After setting the request area 11-i and the response area 12-i in the management area 10-i in this way, the request data is written in the address indicated by the request area start offset (S11), and the handshake flag is set. Set to "Requested" (S12). Next, it is determined whether or not the handshake flag is a value indicating "response is received" (S13). When it is determined in step S13 that the handshake flag has a value indicating "response is present", response data is read from the address indicated by the response area start offset (S).
14). Finally, the handshake flag is returned to a value indicating "usable" (S15), and the area is opened.

In the first to third embodiments, the FA
The case where the present invention is used for the communication between the controller 1 and the programmable controller 2 has been described.
It can also be applied to communication between the A controller 1 and other boards (control devices).

[0075]

As described above, according to the data transfer system and method according to the present invention, all access to the request area and the response area is executed based on the data in the management area, and the management is performed. By changing the values of the request area start offset storage area, the request area length storage area, the response area start offset storage area, and the response area length storage area in the area, the request area becomes a variable length.
By setting the request area small and the response area large, and conversely, when writing is requested, the request area is set large and the response area is set small so that the amount of data handled at one time can be increased.

Further, in multitask processing, a request can be output from a plurality of tasks without waiting time. This means that, for example, when switching the items to be produced in the production line, the sequence program of the programmable controller When rewriting to the production item of
When the last work passes, the programmable controller that has finished the work can download the sequence program, and the setup time can be greatly shortened.

Since the sizes of the request area and the response area in the management area can be controlled by the user program, the request area and the response area can be effectively used according to the request that the user wants to execute.

As a result, in exchanging data between the FA controller and the programmable controller, the shared storage device is effectively utilized, efficient communication is realized without affecting the sequence control of the programmable controller, and the FA controller multi-function is realized. It is possible to shorten the waiting time in task processing.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of an entire data transfer system according to the present invention.

FIG. 2 is an explanatory diagram showing a detailed configuration of a management area according to the present invention.

FIG. 3 is an explanatory diagram showing data structures of request data and response data when the FA controller reads data from the programmable controller.

FIG. 4 is an explanatory diagram showing data structures of request data and response data when the FA controller writes data to the programmable controller.

FIG. 5 is a flowchart showing an operation of communication processing on the FA controller side according to the present invention.

FIG. 6 is a flowchart showing an operation of communication processing on the programmable controller side according to the present invention.

FIG. 7 is an explanatory diagram showing a memory state (first embodiment) of the shared storage device according to the present invention.

FIG. 8 is an explanatory diagram showing states of empty areas and areas (first embodiment) of the shared storage device according to the present invention.

FIG. 9 is an explanatory diagram showing a detailed configuration (second embodiment) of a management area according to the present invention.

FIG. 10 is an explanatory diagram showing an area state (second embodiment) of the shared storage device according to the present invention.

FIG. 11 is a flowchart showing an operation of a user program for reading data of the programmable controller from the FA controller.

FIG. 12 is a block diagram showing a schematic configuration of an entire conventional data transfer system.

[Explanation of symbols]

 1 FA Controller 2 Programmable Controller 3 CPU (For FA Controller) 5 CPU (For Programmable Controller) 7 Shared Memory 10-i Management Area 11-i Request Area 12-i Response Area 20 Handshake Flag Storage Area 21 Request Area Start Offset Storage Area 22 Request area length storage area 23 Response area start offset storage area 24 Response area length storage area 30 Request data 35 Response data 40 Request data 45 Response data 80 Handshake flag storage area 81 Next area number storage area 82 Request area start offset storage area 83 request area length storage area 84 response area start offset storage area 85 response area length storage area

Claims (5)

[Claims] 1. A request area for storing request data, and a management area for providing a plurality of sets of response areas for storing response data and managing the size of the request area and the response area so that each set can have a variable length. A shared storage unit, an FA controller that sets the data size of the request area and the response area, and sets the request data in the request area, and reads the request data from the FA controller, executes a predetermined process, and sets the response area. Write response data, FA
A data transfer system comprising a programmable controller responsive to the controller. 2. The data exchange according to claim 1, wherein the FA controller exchanges data of the programmable controller by setting a request code indicating a request type and a block number indicating the number of request blocks. system. 3. The management area, a flag storage area for storing a value for determining the presence or absence of a request and a response,
Request area head offset storage area that stores the offset value to the start address of the request area, request area length storage area that stores the area length of the request area, and response area head that stores the offset value to the start address of the response area 2. The data transfer system according to claim 1, comprising an offset storage area and a response area length storage area for storing the area length of the response area. 4. The next area number storage area for storing the next area number when two or more request areas or response areas are used in one communication is provided in the management area of the shared storage means. The data transfer system according to claim 1, which is characterized in that. 5. When writing request data to the request area, a usable request area is searched based on the handshake flag of the management area, and the request area length and the response area in the management area are determined according to the size of the request area. A data transfer method comprising updating a head offset, updating a response area length according to a size of response data, and executing data transfer between the FA controller and the programmable controller.