JP3663617B2 - PLC tool device and program recording medium - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a tool device for PLC (abbreviation of Programmable Logic Controller), and in particular, via a data access route for indirectly accessing actual data via data link communication between PLCs, and communication for individual PLCs. In the upper computer for a PLC system having a data access route for directly accessing actual data, the data is the same on the upper application (for example, monitor software, data write software) when using any access route. The present invention relates to a PLC tool device that enables access to target data using the same tag number or tag name as far as possible.
[0002]
[Prior art]
Data on one or two or more PLC stations (generally configured by connecting a CPU unit, I / O unit, communication unit, various high-functional units, etc. via a system bus) and a personal computer that is a PLC tool device A PLC system that is connected by link communication is conventionally known. Here, “data link communication” is a communication method well known to those skilled in the art, and each communication node (PLC station, personal computer, etc.) has a data area ( I / O data, measurement data, etc.), and the contents thereof are automatically and periodically copied together so that the consistency of the entire system is always maintained.
[0003]
The PLC tool device of this type of PLC system includes a first data access route for indirectly accessing actual data via data link communication between PLCs, and communication for each PLC ("message communication"). The second data access route and the second data access route that directly accesses the actual data via the second data access route. The reason for having such two data access routes is that the first data access route is large-capacity and high-speed communication, whereas the second data access route designates data individually and transmits it in a timely manner. This is because communication is different in each route because of communication.
[0004]
A personal computer that is a PLC tool device displays arbitrary data (input / output data, count value, measured value data, set value data, etc.) handled by the PLC system on the screen, or rewrites the data. An application (such as a monitor program) is prepared. In this type of application, in order to make it easy to specify access target data, it has been conventionally performed to use a tag registered in advance. When such a tag is used in an application, the conventional tag management system program automatically converts the tag into an access destination address and executes access control.
[0005]
[Problems to be solved by the invention]
By the way, when the first data access route for indirectly accessing the actual data via the data link communication between the PLCs is adopted, the tag management system program copies the data to the personal computer memory by the data link communication. The stored address of the copied data must be accessed. On the other hand, when accessing actual data directly via communication to individual PLCs (also called “message communication” etc.), the tag management system program accesses the storage address in the PLC station where the actual data is stored. Must.
[0006]
However, in the conventional tag management system program, the designated tag is merely converted into one specific access destination address, so that direct access is performed as described above. If the destination physical addresses are different, the final accessed data itself is the same, but different tags must be registered for each data access route. There was the complication that it was necessary to use properly according to the access route.
[0007]
The present invention has been made paying attention to the above-mentioned problems in the conventional tag management system program, and the object thereof is indirectly to the actual data via the data link communication between the PLCs. In a PLC tool device that has both a data access route to be accessed and a data access route to directly access actual data via communication with each PLC, as long as the data to be finally accessed is the same, On the side, a single tag is used, and regardless of whether it is read or written, it is possible to reliably access the data by specifying the desired data with the tag without being aware of the data access route. .
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the PLC tool device of the present invention indirectly accesses actual data via data link communication between PLCs. First Direct access to actual data via data access route and communication to individual PLC Second In the configuration with the data access route,
In response to the tag being given from the host application, the access destination address of the actual data related to the data corresponding to the tag, the access destination address of the copy data by the data link, and the data Specifies whether to use the first or second data access route for access Tag decoding means for decoding the access mode;
Access control for accessing the target data while automatically selecting the data access route according to the access address of the decrypted real data, the access address of the copy data by the data link, and the access mode for the data Means,
It is characterized by comprising.
[0009]
In the PLC tool device according to the preferred embodiment, the tag decoding means refers to a preset table so that the access destination address of the actual data related to the data corresponding to the tag and the access of the copy data by the data link It is configured to decrypt the destination address and the access mode for the data.
[0010]
In the PLC tool device according to the preferred embodiment, the table structure is such that the access destination address and the access mode of the actual data are stored in association with each tag, and the tag decoding means accesses the actual data. The process of obtaining the access destination address of the copy data by the data link from the destination address is configured to be performed based on the data link allocation information.
[0011]
In the PLC tool device according to the preferred embodiment, the table structure associates the access destination address of the actual data, the access destination address of the copy data by the data link, and the access mode for the data for each tag. Configured as a memorized one.
[0012]
In the PLC tool device of the preferred embodiment, the access mode is configured such that two or more codes indicating which data access route is used at the time of reading and / or writing are defined.
[0013]
According to the above-described PLC tool device of the present invention, the data access route for indirectly accessing the actual data via the data link communication between the PLCs, and the actual access via the communication for each PLC. In a PLC tool device that has a data access route that directly accesses data, as long as the data to be finally accessed is the same, a single tag is used on the application side, and it is not related to read or write. Therefore, it is possible to make sure that the desired data can be accessed by simply specifying the desired data with the tag without being aware of the data access route.
[0014]
Further, the PLC tool device of the present invention has an input means for inputting the tag, the access destination address of the actual data, and the access mode for the data desired to be accessed,
Address conversion means for obtaining an access destination address of copy data by the data link by referring to the data link allocation information based on the address of the input actual data;
A table creating means for storing the input address of the actual data, the access address of the copy data obtained by the conversion, and the input access mode as a table in association with the corresponding tag;
It is characterized by comprising.
[0015]
According to the present invention, if only an access destination address of actual data is designated, an access destination of copy data by a corresponding data link is automatically registered, and this kind of registration work can be simplified.
[0016]
The recording medium of the present invention stores a program for realizing the functions of the decoding means and the data access control means of the above PLC tool device by a computer.
[0017]
Furthermore, the recording medium of the present invention stores a program for realizing the functions of the input means, address conversion means, and table creation means of the above-described PLC tool device.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. A general view of a PLC system to which the present invention is applied is schematically shown in FIG. As shown in the figure, this PLC system is composed of two PLC stations 2 and 3 (generally connecting a CPU unit, an I / O unit, a communication unit, various high-function units, etc. to each other via a system bus). The personal computer 1 or the like as a PLC tool device is connected to each other via a communication line 4. The personal computer 1 and the two PLC stations 2 and 3 are connected via so-called data link communication. Here, “data link communication” means that, as is well known to those skilled in the art, each communication node (PLC station, personal computer, etc. has its own data area and I / O data) And measurement data, etc.), and the contents of these areas are automatically and periodically copied together to maintain the consistency of the entire system.
[0019]
If the personal computer 1 is the node # 1, the PLC station 2 is the node # 2, and the PLC station 3 is the node # 3, each of the nodes # 1 to # 3 includes the memories M1 to M3 constituting the data area. ing. Each of the memories M1 to M3 is divided into three areas respectively assigned to the nodes # 1 to # 3. The # 1 area in the memory M1, the # 2 area in the memory M2, and the # 3 area in the memory M3 are the actual data storage areas A1, and the other areas in the memories M1 to M3 are the copy data storage areas A2. Has been. The contents of the actual data storage area A1 in each of the memories M1 to M3 are transferred at regular intervals to the copy data storage area A2 of the corresponding node in the memory. As a result, the contents of the areas of the corresponding nodes # 1 to # 3 in the memories M1 to M3 are consistent with each other.
[0020]
A personal computer 1, which is a PLC tool device of this type of PLC system, has a first data access route 5 for indirectly accessing actual data via data link communication between nodes, and each PLC station. Two data access routes are provided, including a second data access route 6 for directly accessing actual data via communication (also referred to as “message communication” or the like). The reason for having such two data access routes 5 and 6 is that the first data access route is large-capacity and high-speed communication, whereas the second data access route designates data individually and is timely. This is because there is a difference in usage in each route because the communication is transmitted to the network.
[0021]
An example of link data assignment and an example of a data link table in data link communication are shown in FIGS. As shown in FIG. 2, in the memory area 1 of the node # 1, copy data for 20 channels related to the node # 2, copy data for 30 channels related to the node # 3, and actual data for 15 channels related to the node # 1 Are stored. Similarly, in the memory area 1 of the node # 2, copy data for 15 channels related to the node # 1, real data for 20 channels related to the node # 2, and copy data for 30 channels related to the node # 3 are sequentially stored. ing. Similarly, in memory area 1 of node # 3, actual data for 30 channels related to node # 3, copy data for 15 channels related to node # 1, and copy data for 20 channels related to node # 2 are sequentially stored. ing. As described above, the actual data area in each memory area is a transmission (write) area to other nodes, and the other copy data areas are reception (read) areas from other nodes.
[0022]
The link data assignment shown in FIG. 2 is defined based on the description of the data link table shown in FIG. That is, each of the nodes # 1 to # 3 is provided with a data link table as shown in FIG. As apparent from comparison between FIG. 2 and FIG. 3, the link source channel (actual data storage address) of the stored node data is stored in each of the data link tables of the nodes # 1 to # 3. Has been. Therefore, by referring to this data link table, it is possible to easily know the address where the actual data of each stored data is stored. For example, referring to the data link table of the node # 1, it can be known that the link source channel of the data related to the node 2 stored for 20 channels from the link channel 00100 is 00195. Similarly, it can be known that the link source channel of the data related to the node 03 stored for 30 channels from the link channel 00120 is 00100.
[0023]
Returning to FIG. 1, on the personal computer 1 which is a PLC tool device, arbitrary data handled by the PLC system (input / output data, counter value, measured value data, set value data, etc.) is displayed on the screen. Alternatively, an application (such as a monitor program) for rewriting such data is prepared. In this type of application, a tag registered in advance is used in order to make it easy to specify access target data. When such a tag is used in an application, the tag management system program automatically converts the tag into an access destination address and executes access control.
[0024]
Next, a first embodiment of a PLC tool device according to the present invention will be described with reference to FIGS. 4 is a flowchart showing a tag registration operation procedure according to the first embodiment, FIG. 5 is a flowchart showing a tag management table according to the first embodiment, and FIG. 6 is a flowchart showing tag decoding and access control processing according to the first embodiment.
[0025]
As shown in FIG. 4, when registering a tag, first, a tag number for designating data to be accessed is determined (step 401). What is important here is that the previous tag number has a one-to-one correspondence with the address of the data to be accessed, whereas the tag number of the present invention corresponds to the data to be accessed. However, it does not correspond one-to-one with the storage address.
[0026]
If the tag number is determined in this way, the actual data storage address corresponding to the designated tag number is registered (step 402). For example, in the example of FIG. 2, the real addresses registered here are addresses indicated by hatching for the channels 150015 to 15 in the memory area 1 of the node # 1, and the memory area of the node # 2. 1 corresponds to an address corresponding to 20 channels from the channel 00205 in the channel 1 and an address corresponding to 30 channels from the channel 00015 in the memory 1 of the node # 3.
[0027]
When the real address registration of the designated tag number is completed in this way, the access mode is registered next. Here, as the access mode, three types of codes indicating which data access route is used at the time of reading and / or writing are defined.
[0028]
When the code indicating the type of the access mode is “1”, it means that the personal computer 1 indirectly accesses the actual data via the data link communication when the data is read, but does not execute the data write. . In this case, the personal computer 1 uses the corresponding copy data address in its own memory M1 as the data read destination address.
[0029]
The code indicating the access mode type is “2”, which means that the personal computer 1 adopts a data access route for indirectly accessing the actual data via data link communication when reading data, while when writing data. This means adopting a data access route for directly accessing actual data via communication with each PLC stage. In this case, the personal computer 1 uses the corresponding copy data address in the memory M1 as the data read destination, while using the corresponding actual data address in the memory M2 or M3 as the data write destination address.
[0030]
That the code indicating the type of access mode is “3” means that the personal computer 1 directly accesses the actual data via communication with the individual PLC when reading data, and similarly when writing data. This means adopting a data access route that directly accesses actual data via communication with each PLC. In this case, the personal computer 1 uses the corresponding actual data address in the memory M2 or M3 as a data read destination, and also uses the corresponding actual data address in the memory M2 or M3 when writing data.
[0031]
Returning to the flowchart of FIG. 4, assuming the above access mode, the receiving destination (read destination) is to be the data link area of a node other than the node holding the actual data (for example, node # 1). If this is the case (step 403 YES) and transmission (data write) is not performed (step 404 NO), “1” may be registered as a code indicating the type of the access mode (step 405).
[0032]
In addition, when it is desired to set the reception (data read) destination to the data link area of another node (for example, node # 1) other than the node holding the actual data (step 403 YES), and the transmission (data write) destination If it is desired to specify a node storing actual data (step 404 YES), “2” may be registered as a code indicating the type of access mode (step 406).
[0033]
Furthermore, when the destination (data read) destination is a node storing actual data (step 403 NO), “3” may be registered as a code indicating the type of the access node (step 407).
[0034]
The table of FIG. 5 shows the contents of the tag management table registered by the tag registration operation procedure described above. As shown in the figure, in the tag management table, a tag number, a code indicating an access mode, a tag name, and an actual data storage address are stored in association with each other. Here, in the notation indicating the address, WW indicates a network number, NN indicates a node number, GG indicates a machine number, and AAAAA indicates a memory address. As is apparent from this table, if the tag number is designated, the access mode and the actual data storage address can be obtained.
[0035]
The structure of the tag decoding and access control processing program for realizing the PLC tool device according to the present invention is schematically shown in the flowchart of FIG. When the tag number is designated in the upper application (step 601), the tag management table shown in FIG. 5 is referred to based on the designated tag number, so that actual data relating to the data corresponding to the tag number is obtained. , The access destination address of the copy data by the data link, and the access mode for the data are decoded.
[0036]
Specifically, first, by referring to the tag management table shown in FIG. 5 based on the designated tag number, acquisition of the access destination address of the actual data related to the data corresponding to the tag number (step 602), and Then, a code indicating the type of access mode for the data corresponding to the tag number is acquired (step 603).
[0037]
Thereafter, depending on which of the acquired access mode types is “1” to “3” (step 604), an access control process for accessing the target data while automatically selecting the data access route is performed. Executed.
[0038]
That is, if it is determined that the access mode of the designated tag number is “1”, the actual data address acquired in step 602 is converted into the address of the data link area (step 605), and this conversion The obtained address is set as the receiving address (step 606).
[0039]
If it is determined that the access mode of the designated tag number is “2”, the address acquired in step 602 is converted into the address of the data link area (step 607), and the converted address is the receiving destination. It is set as an address (step 608), and the address of the actual data acquired in step 602 is set as the transmission destination address as it is (step 609).
[0040]
When it is determined that the access mode of the designated tag number is “3”, the address of the actual data acquired in step 602 is set as the reception destination (step 610), and at the same time, it is set as the transmission destination address. (Step 611).
[0041]
Note that the above address conversion process is performed by referring to the data ring table of each node as described above (see FIGS. 2 and 3).
[0042]
After any one of the three types of address conversion processing is executed, the result of receiving from the destination address (data read) and sending to the destination address (data write) (steps 612 and 613), first Control operations of the defined access modes “1” to “3” are realized.
[0043]
That is, when the access mode of the designated tag number is determined to be “1”, reception (data read) is performed from the data link area of the personal computer (node # 1), but transmission (data write) is not performed. . If it is determined that the access mode of the designated tag number is “2”, reception (data read) from the data link area of the personal computer (node # 1) is performed, while the message is communicated to the designated node. Is transmitted (data write). Further, when it is determined that the access mode of the designated tag number is “3”, reception from the designated node by message communication (data read) is performed, while transmission to the designated node by message communication (data write) ) Is performed.
[0044]
As a result, as long as the data to be finally accessed is the same, a single tag is used on the application side, and the desired data can be used regardless of the data access route regardless of read or write. It is possible to ensure that the data can be accessed simply by designating with a tag.
[0045]
Next, a second embodiment of a PLC tool device according to the present invention will be described with reference to FIGS. FIG. 7 is a flowchart showing the tag registration operation procedure and registration processing of the second embodiment, FIG. 8 is a diagram showing a tag management table of the second embodiment, and FIG. 9 is a tag decoding and access control processing of the second embodiment. It is a flowchart.
[0046]
When registering a tag, first, as in the first embodiment, determination of a tag number (step 701) and registration of an entity address relating to data corresponding to a specified tag number (step 702) were performed. Thereafter, the access mode is registered (steps 705, 708, and 712) in accordance with the previous determination (steps 703 and 704).
[0047]
At this time, if the access mode is registered as “1” (step 705), the actual address registered in step 702 is converted into the address of the data link area (step 706), and then the converted address is changed. It is registered as a receiving address (step 707).
[0048]
When the access mode is registered as “2” (step 708), the entity address registered in step 702 is directly registered as the transmission destination address (step 709), while the entity address is set to the address of the data link area. After conversion (step 710), the address obtained by this conversion is registered as a receiving address (step 711).
[0049]
Furthermore, when the access mode is registered as “3” (step 712), the actual address obtained in step 702 is transmitted as it is as the destination address (step 713), and the same address is further received as the destination. It is also registered as an address (step 714).
[0050]
The contents of the tag management table obtained by such registration processing are shown in the table of FIG. As shown in the figure, in this tag management table, a tag number, an access mode, a tag name, an actual address, a reception destination address, and a transmission destination address are stored in association with each other. Therefore, by referring to this tag management table, it is possible to immediately acquire the reception destination address and the transmission destination address based on the tag number without executing the address calculation process as in the first embodiment. The above address conversion is also performed by referring to the data link table of each node.
[0051]
Therefore, as shown in the flowchart of FIG. 9, the contents of the tag decoding process and the access control process are significantly simplified as compared with the first embodiment. That is, in this process, first, in response to the tag number designation by the upper application (step 901), the reception address and the transmission destination address are obtained immediately from the designated tag number (steps 902 and 903). After that, only reception (data read) and transmission to the transmission destination (data write) are executed from the reception destination (steps 904 and 905), and as long as the finally accessed data itself is the same, the application side simply Regardless of whether a single tag is used or read or written, the data access route can be reliably accessed only by designating the desired data to the tag without being aware of the data access route.
[0052]
【The invention's effect】
As is clear from the above description of the embodiment, according to the present invention, the data access route for indirectly accessing the actual data via the data link communication between the PLCs and the communication for each PLC are used. In a PLC tool device having a data access route that directly accesses actual data, a single tag is used on the application side as long as the data to be finally accessed is the same, and the read Regardless of the write, it is possible to ensure that the data can be accessed by simply designating the desired data with the tag without being aware of the data access route.
[Brief description of the drawings]
FIG. 1 is an overall view of a PLC system of the present invention.
FIG. 2 is an explanatory diagram of data link communication.
FIG. 3 is a configuration diagram showing an example of a data link table.
FIG. 4 is a flowchart illustrating a tag registration operation procedure according to the first embodiment.
FIG. 5 is a diagram showing the contents of a tag management table of the first embodiment.
FIG. 6 is a flowchart showing tag decryption and access control processing according to the first embodiment;
FIG. 7 is a flowchart illustrating a tag registration operation procedure and a registration process according to the second embodiment.
FIG. 8 is a diagram illustrating the contents of a tag management table according to the second embodiment.
FIG. 9 is a flowchart showing tag decryption and access control processing according to the second embodiment;
[Explanation of symbols]
1 PC
2,3 PLC station
4 communication lines
5 First data access route
6 Second data access route
M1 PC memory
M2, M3 PLC station memory
A1 Actual data storage area
A2 Copy data storage area

Claims (4)

A first data access route that indirectly accesses actual data via data link communication between PLCs and a second data access route that directly accesses actual data via communication to individual PLCs are combined. A PLC tool device comprising:
In response to the upper application of the tag is given, access destination address of the real data about the data corresponding to the tag, the access destination address of the copy data by the data link communication, and the first or second for the corresponding data Tag decryption means for decrypting an access mode for designating which data access route is used to access ,
Access control for accessing the target data while automatically selecting the data access route according to the access address of the decrypted real data, the access address of the copy data by the data link, and the access mode for the data Means,
A PLC tool device comprising: With respect to data to be accessed, an input means for inputting the tag, the access destination address of the actual data, and the access mode;
Address conversion means for obtaining an access destination address of copy data by the data link by referring to the data link allocation information based on the address of the input actual data;
A table creating means for storing the access destination address of the input actual data, the access destination address of the copy data obtained by the conversion, and the input access mode as a table in association with the corresponding tag; ,
A PLC tool device, wherein the decoding process in the tag decoding means is performed by referring to the table .   A recording medium storing a program for realizing the functions of the decoding means and the data access control means according to claim 1 by a computer.   A recording medium storing a program for realizing the functions of the input unit, the address conversion unit, and the table creation unit according to claim 2.

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