JP2000047717A - Programmable controller system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the operation efficiency when a specified tool is placed in operation, and to suppress the device cost. SOLUTION: A PLC(programmable controller) 1 reads out a transmission destination from a command message received from a personal computer 2, performs the process based upon the command message when the read transmission destination is itself, and then sends a response message to the command message to the personal computer 2. The PLC 1, on the other hand, sends the command message to a 2nd PLC 1a when the read destination is the 2nd PLC 1a and it sends a response message to the personal computer 2 when receiving the response message from the 2nd PLC 1a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a programmable controller system constructed with a plurality of programmable controllers and a personal computer.

[0002]

2. Description of the Related Art In recent years, a programmable controller for controlling a sensor, an actuator, and the like has a high function, which comprises a CPU unit 50 and an NC unit connected to the CPU unit 50 via a system bus 90, as shown in FIG. It comprises an I / O unit 60 and a communication unit 70 for transmitting and receiving data to and from other communication units.

The CPU unit 50 controls a high-performance I / O unit 60 and a communication unit 70 provided on a rack.
0, a personal computer 80 for running a tool (application software) for setting data and a tool 2 (application software) for executing monitoring by the high-performance I / O unit 60.

The high-performance I / O unit 60 performs special controls, for example, NC control and PID control.

The communication unit 70 is provided with another CPU unit 50 or high-performance I / O unit 60 serving as another node.
And send and receive data.

[0006]

In the above-described conventional programmable controller, the personal computer 80 connected to the CPU unit 50 is connected to the CPU unit 5.
A tool 1 for setting data to 0 or a tool 2 (application software) for executing monitoring by the high-performance I / O unit 60 is operated.
Since a plurality of applications cannot be simultaneously communicated with the CPU unit 50 on the personal computer 80, if the tool 1 is running, the
When it is desired to operate the tool 1, the operation of the tool 1 has to be stopped once and then the tool 2 has to be operated, resulting in a problem that the work efficiency is low.

[0007] As shown in FIG. 15, a personal computer 90 is further connected to the high function unit 60.
Executing the tool 2 for executing the monitoring by the high-performance I / O unit 60 solves the above-described problem, but requires an extra personal computer and increases the device cost.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a programmable controller system that improves work efficiency and reduces equipment costs when operating a predetermined tool.

[0009]

In order to achieve the above-mentioned object, according to the present invention, a personal computer comprises:
When a command to transmit to the programmable controller is received from the tool, the formed command message is stored in the transmission buffer, and a response message to the command message transmitted to the programmable controller is stored in the reception buffer. Even without receiving a response message to the command message, the command message can be transmitted based on the instruction of the tool.

In the present invention, a programmable controller reads a destination from a command message received from a personal computer, and if the read destination is addressed to itself, executes a process based on the command message. Then, a response message to the command message is transmitted to the personal computer.

On the other hand, when the read destination is the second programmable controller, the programmable controller transmits a command message to the second programmable controller, and upon receiving a response message from the second programmable controller, The received response message is transmitted to the personal computer.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a programmable logic controller system according to the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a programmable logic controller system according to the present invention.

A programmable logic controller system (hereinafter, referred to as a PLC system) according to this embodiment.
Is a first programmable controller (hereinafter referred to as a first programmable controller) that controls a device to be controlled such as a sensor or an actuator.
LC), a second programmable controller (hereinafter, referred to as a second PLC) 1a, and a personal computer (hereinafter, referred to as a personal computer) 2 that runs a tool described later.

The first PLC 1 includes a CPU unit 11
, A high-performance unit 12 and a communication unit 13, which are connected to a system bus 14 including a data bus, an address bus, and the like.

The CPU unit 11 controls the high-performance I / O unit 12 and the communication unit 13 provided on the rack, and controls the personal computer 2 via the tool cable 3.
And executes a predetermined process of the tool received from the personal computer 2.

The CPU unit 12 is a microcomputer (microcomputer) 1 for controlling the CPU unit itself.
11 and the microcomputer 111 are connected to the system bus 1
A microcomputer bus ASIC 112 for providing an interface for accessing each of the units 12 and 13 through the microcomputer 4;
A memory 113 for storing a plurality of data received from the tool (hereinafter, referred to as a command message) and for storing transmission data (a response message) to be transmitted to the tool, and a communication processing program for storing a communication processing program for performing a communication process The memory 114 is provided.

As shown in FIG. 2, the communication processing program includes a command receiving means 114a for receiving a command message received from the personal computer 2, a response forming means 114b for forming a response message to the command message, and a response forming means 114b. Transmitting means 114c for transmitting the response message formed in step (1) to the personal computer 2.
Destination reading means 114d for reading the destination from the command message received by the command receiving means 114a
The destination of the transmission means read by the transmission destination reading means 114d is determined, and if it is determined that the destination is the second PLC 1a, the command message is transferred to the communication unit 13 while the destination is determined by itself. When it is determined that there is a response message, a destination determining unit 114e that outputs an instruction to cause the response forming unit 114b to form a response message to the command message is provided.

The high-performance I / O unit 12 is a unit for performing special control, for example, an NC unit.
A microcomputer (microcomputer) 121 for controlling the high-performance I / O unit itself, a bus ASIC 122 for interfacing the system bus 14 with this unit,
The memory 123 stores a command transmitted from the CPU unit 11 and a response transmitted to the CPU unit 11.

The communication unit 13 includes a CPU unit 11
And transmits a command message received from the communication unit to a communication unit of another connected node, and receives a response thereto and the like to the CPU unit 11 to control the communication unit itself. A microcomputer (microcomputer) 131,
A bus ASIC 132 for interfacing the system bus 14 with this unit; and a memory 133 for storing commands and the like transmitted from the CPU unit 11 and a response message transmitted to the CPU unit 11.
And a configuration having:

The personal computer 2 is capable of displaying a plurality of windows on a display screen. Using this window, a plurality of tools 21 (application software) (in the drawing, the tools 21 and # 2 of the tools # 1 and # 2) are displayed. A tool 21) is executed.

As shown in FIG. 3, the personal computer 2 includes tools # 1 to #n and an OS (Operat
ing System) 22 and communication drivers 23 # 1 to #m
And a transmission buffer 24 provided for each communication driver 23
And a reception buffer 25, a communication port 26 provided for each communication driver 23, a transmission tool correspondence table 27 described later, and a reception tool correspondence table 28 described later.
It is composed of

The tools 21 of # 1 to #n allow the CPU unit 11 to set a predetermined data value.
In some cases, monitoring of a device to be controlled controlled by the O unit 12 is performed.

The OS 22 is an OS used in a commercially available personal computer, for example, a window 95.
/ NT and the like, by performing time sharing of the execution of a plurality of tasks (software), it is as if the tasks are being executed simultaneously.

The communication drivers 23 of # 1 to #m form a command message having a frame structure according to a protocol when transmitting the command message to a predetermined node based on the instruction of the tool 21 of #i. The formed command message is transmitted to the transmission buffer 24.

Further, the communication drivers 23 of # 1 to #m
When a response message addressed to the tool 21 of #j is received from the reception buffer 25, message data is formed from the received response message, and the message data is formed.
1 is output.

The processing for forming the command message by the communication drivers 23 of # 1 to #m and the processing for forming the message data from the received response message are as follows.
Details will be described later.

The transmission buffer 24 temporarily stores data until a command message composed of a frame conforming to the communication protocol formed by the communication driver 23 is transmitted.

The reception buffer 25 temporarily stores a response message received from another node.

The communication ports # 1 to #m are paired with the communication driver 23, and are connected to I / Os for connecting to external devices generally owned by personal computers.
F or a serial I / F (RS232C or the like) composed of an I / F connected to an extended external device by incorporating an extension board into a personal computer.

The transmission tool correspondence table 27 is shown in FIG.
As shown in (a), when a command message is transmitted, a tool 21 for transmitting the command message is transmitted.
It stores transmission tool correspondence data having a sequential ID which is a value for identifying a command message formed by the communication driver 23 based on the instruction of the tool 21.

The sequential ID is determined in a range of possible values for each tool 21, for example, in a range of 10. This means that when the command message formed by the communication driver 23 cannot be transmitted, the number of retries that can form and transmit the same command message is defined.

By the way, the transmission tool corresponding data indicated by A indicates that the command message formed in the communication device 23 is based on the instruction from the tool of # 2 and that the number of retries is 0. I have.

The receiving tool correspondence table 28 is shown in FIG.
As shown in (b), when a response message is received, reception tool correspondence data including a tool 21 to which the received response message is output and a message ID for specifying the received response message is stored. Things.

By the way, in the reception tool correspondence data marked with B, the destination of the response message received by the communication driver 23 is that of the tool 21 of # 4, and the number of retries until this response message is received is indicated. 3
Is shown.

Here, the frame structure of the command message and the response message will be described.

FIG. 5 is a frame diagram showing the frame structure of the command message and the response message.

As shown in FIG. 5A, the command message includes a command header 1 for specifying the type of the message.
A, a destination address and a source address 1B, and a sequential ID (SI
D) 1C and data (command data) 1D to be transmitted to the transmission destination have a frame configuration.

As shown in FIG. 5B, the response message includes a response header 2A for specifying the type of the message, a destination address and a source address 2B, and a sequential ID for specifying the response message.
(SID) 2C and a data (response data) 2D in the transmission tool 21.

Next, the operation of the PLC system of this embodiment will be described by dividing it into (1) the operation of the first PLC 1 and (2) the operation of the personal computer 2.

(1) Operation of First PLC 1 The operation of the first PLC 1 will be described with reference to FIG.

Command receiving means 114 of first PLC 1
When a receives the command message from the personal computer 2 (see FIG. 2), it outputs the received command message to the transmission destination reading means 114d (see FIG. 2).

Next, the transmission destination reading means 114d reads the transmission destination from the received command message, and outputs the read transmission destination to the destination determining means 114e (see FIG. 2).

Upon receiving the transmission destination from the destination reading unit 114d, the destination determination unit 114e determines the destination, and transfers the command message to the communication unit 13 when determining that the destination is the second PLC 1a. On the other hand, if it is determined that the destination is the self, an instruction to form a response message to the command message is output to the response forming unit 114b (see FIG. 2).

The response forming means 114b sends an instruction to form a response message to the destination determining means 11
4e, it forms a response message and outputs it to the response transmission means 114c.

When receiving the response message from the response transmitting means 114b or the second PLC 1a (see FIG. 2), the response transmitting means 114c
This response message is sent to the personal computer 2
(See FIG. 2).

(2) Operation of Personal Computer 2 Here, the operation of the personal computer 2 will be described.
The operation of transmitting a command message to the first PLC 1 (CPU unit 11) and the operation of receiving a response message from the first PLC 1 (CPU unit 11) will be described separately.

The command message is sent to the first PLC 1
Regarding the operation of transmitting to the (CPU unit 11) The tool 21 that has output the instruction to transmit this command message is the tool 21 of #j.

The tool 21 of #j of the personal computer 2 is connected to a destination of a predetermined node (CPU unit 11).
When the instruction to transmit a command message to the communication driver 23 of #i via the OS 22 and the command data 1D is transmitted to the communication driver 23 of #i, the communication driver 23 of #i The command data 1D received from 21 is stored in the built-in #j transmission buffer 231 (see FIG. 6).

Subsequently, the communication driver 23 of #i refers to the transmission tool correspondence table 27 (see FIG. 6), adds the sequential ID 1C before the command data, and further adds the sequential ID 1C before the command data. To the destination address and the source address 1B of this command data.
A command header 1A is added before B to form a command message, and the formed command message is stored in the transmission buffer 24 (see FIG. 6).

The communication port 26 of #i is connected to the transmission buffer 2
4 stores the command message 24, the command message is read (see FIG. 6) and transmitted to the destination of the command message (see FIG. 6).

The response message is sent to the PLC 1 (CP
Operation Received from U Unit 11) Here, the tool 21 that receives the received response message is a tool of #k.

Upon receiving the response message (see FIG. 6), the communication port #i stores this message in the reception buffer (see FIG. 6).

When the response message is stored in the reception buffer 25, the communication driver #i reads out the stored response message, and confirms that the type of the message indicated by the response header is the response message. After reading the destination address (address of the tool 21 of #k), the source address 2B, and the sequential ID 2C from the message,
With reference to the destination address (the address of the tool 21 of #k), the receiving tool data of #k is stored in the receiving tool correspondence table 28 (see FIG. 6).

When the #i communication driver 23 stores the #k receiving tool correspondence data in the receiving tool correspondence table 28, the communication driver 23 stores the response header 2A, the transmission destination address and the transmission source address 2B, and the sequential ID 2C from the response message. The response data is removed to form response data, and this is stored in the #k reception buffer 232 (see a in FIG. 6).

The tool 21 of #k, via the OS 22,
#K reception buffer 2 included in #i communication driver 23
The response data is read from the address 32 (see b in FIG. 6).

In the PLC system of the present embodiment, the personal computer 2
1 receives the instruction to transmit the command message, stores the formed command message in the transmission buffer 24, and
By storing the response message to the command message transmitted to the first PLC 1 in the reception buffer 25, the command message can be transmitted based on the instruction of the tool 21 without receiving the response message to the command message. it can.

Therefore, the operation efficiency of the tool 21 can be improved when the tool 21 is operated, and the cost can be reduced by eliminating the necessity of providing a plurality of personal computers 2.

Here, the first PLC 1 reads the transmission destination from the command message received from the personal computer 2, and executes the processing based on the command message when the read transmission destination is addressed to itself.
After that, a response message to the command message is transmitted to the personal computer 2.

On the other hand, when the read destination is the second PLC 1a, the first PLC 1 transmits the command message to the second PLC 1a, and receives the response message from the second PLC 1a. A response message is transmitted to the personal computer 2.

In the PLC system of this embodiment, the personal computer 2 and the CPU unit 11, and the personal computer 2 and the other CPU units 11 through the CPU unit 11 and the communication unit 13, having the above-described configuration. Is transmitted as shown in FIG.

That is, the personal computer 2
As shown in FIG. 7, first, a command message 1 is transmitted to the CPU unit 11, a second is transmitted to another CPU unit 11 via the CPU unit 11 and the communication unit 13, and a third message is transmitted. To C
When the command message 3 is transmitted to the PU unit 11, the response message 1 corresponding to the command message 1 is transmitted from the CPU unit 11, and then the response message 3 corresponding to the command message 3 is transmitted from the CPU unit 11. Response message 2 for command message 2
Will be sent.

Incidentally, in the conventional PLC system, if a command message is received from a tool of a personal computer and a response message corresponding to the command message is not returned, the next command message cannot be transmitted.

Therefore, the personal computer 2 and the CP
The transmission process between the personal computer 2 and another CPU unit 11 via the U unit 11, the CPU unit 11, and the communication unit 13 is as shown in FIG.

That is, the personal computer 2
As shown in FIG. 8, first, a command message 1 is transmitted to the CPU unit 11, and after a response message 1 to the command message is received, the other CPU units are transmitted via the CPU unit 11 and the communication unit 13. 11, a command message 2 is transmitted, and a response message 2 corresponding thereto is received.

FIG. 9 is a functional block diagram showing a functional configuration of the personal computer 2 shown in FIG.

In FIG. 9, the personal computer 2
Is SPMA (SinglePort Multiple Acces
s) It has a corresponding SPMA application 201. In this example, three SPMA applications (1), (2), and (3) are running, and two SPMA applications (1) and (2) are the same external device, for example, the external devices 100-1 to 100-1. The other SPMA application (3) is connected to an external device 100-1 of the external device 100-3.
The figure shows a state where the external device 100-2 is connected to the external device 100-2.

Here, the external devices 100-1 to 100-3
Corresponds to the first PLC 1, the second PLC 1a, etc. shown in FIG.

The communication processing unit 202 performs external device ID assignment and command assignment corresponding to the two SPMA applications (1) and (2) (process 202-1), and also supports the SPMA application (3). In the same manner, external device ID allocation and command allocation are performed (process 20).
2-2), Generate a Communication Command (Process 202-)
3).

The personal computer hardware unit 203 has a personal computer communication buffer 203-1 and a personal computer communication physical port 203-2.
2 is stored in the communication buffer 203-1 in the personal computer, and the communication physical port 203 in the personal computer is stored.
-2 to the external devices 100-1 to 100-3.

The responses from the external devices 100-1 to 100-3 are transmitted to the communication physical port 203-in the personal computer.
2 through the communication buffer 203-1 in the personal computer.
And returns it to the corresponding SPMA application.

FIG. 10 is a flowchart showing the overall operation of the personal computer 2 shown in FIG.

Referring to FIG. 10, an SPMA application (SP
MA compatible applications), specifically three SPMA applications (SPMA applications) (1), (2),
The state where (3) is activated (step 211) is shown.

While the SPMA application (1) is being executed (step 212), it is checked whether there is a request communication command from the SPMA application (1) (step 213). If not (No in step 213), the process proceeds to step 212. Returning, if there is (Yes in step 213), processing 1 for adding this communication command to the communication command management stack
Is executed (step 218).

During the execution of the SPMA application (2) (step 214), it is checked whether there is a request communication command from the SPMA application (2) (step 215).
If not (No in Step 215), Step 214
When there is (YES in step 215), processing 1 for adding this communication command to the communication command management stack is executed (step 218).

During the execution of the SPMA application (3) (step 216), it is checked whether there is a request communication command from the SPMA application (3) (step 217).
If not (No in Step 217), Step 216
If there is (Yes in step 217), processing 1 for adding this communication command to the communication command management stack is executed (step 218).

Then, the communication physical port 203 in the personal computer
-2 is transmitted (step 219).

The details of the process 1 in step 218 will be described later with reference to the flowchart shown in FIG.

Next, it is checked whether or not responses have been received from the external devices 100-1 to 100-3 (step 21).
0). If no response has been received from the external device 100-1 to 100-3 (No in step 210), the process returns to step 219, but the external device 100-1
If a response from the corresponding command transmission source is received, the processing 2 for returning the received response to the corresponding command transmission source SPMA application is executed (step 211).

The details of the process 2 in step 218 will be described later with reference to the flowchart shown in FIG.

FIG. 11 is a flowchart showing the operation of step 218 shown in FIG.
6 is a flowchart showing details of processing 1 of FIG.

In processing 1 shown in FIG.
When processing for registering a command for an external device requested by the application (m) (M = 1, 2, 3) in the communication command management stack is started (step 231), first, the SP
An external device ID and a command ID are assigned to the external device requested by the MA application (m), and registered in the communication command management stack (step 232).

Next, the contents of the communication command management stack are transferred to the communication buffer 203-1 in the personal computer 2 (step 233). Then, it is checked whether the communication buffer 203-1 in the personal computer is full (step 23).
4) If it is full (Yes in step 234),
Returning to step 233, if not full (No in step 234), a command ID is assigned to the external device and transmitted (step 235).

FIG. 12 is a flowchart showing the operation of step 221 shown in FIG.
9 is a flowchart showing details of processing 2 of FIG.

In the process 2 shown in FIG. 12, first, the external device ID included in the response information from the external device
And its command ID are analyzed (step 241).

Next, the analyzed external device ID and command I
S registered in the communication command management stack from D
The PMA application number is determined (step 242). Then, the content of the response from the external device is extracted, and the
Return to the PMA application (step 243).

In the PLC system of the present invention, as shown in FIG.
PLC on network just by specifying PLC name
It is possible to connect easily. In this case, FIG.
As shown in (a), the P directly connected to the personal computer 2
Not only LC but also its PL as shown in FIG.
When accessing (remote programming / monitoring) a PLC on the network via C, it is possible to easily connect simply by specifying the PLC name of the PLC serving as the gateway.

It is also possible to collect information such as the status of the dip switch and the operation mode relating to the PLC on the remote network by simply designating the PLC name from the personal computer 2.

[0089]

As described above, according to the first aspect of the present invention, the first programmable controller and the first programmable controller
A programmable controller system constructed by a second programmable controller connected to the first programmable controller and a personal computer connected to the first programmable controller,
The first programmable controller, when the command message transmitted from the personal computer is a command message addressed to itself,
A response message to the command message is transmitted to the personal computer. On the other hand, when the response message is a command message addressed to the second programmable controller, the response message is transmitted to the second programmable controller, and transmitted from the second programmable controller. Since the response message sent to the personal computer is configured to be transmitted to the personal computer, the personal computer is connected not only to the first programmable controller directly connected to the personal computer but also to the personal computer via the first programmable controller. Can also communicate with the second programmable controller connected to.

According to the second aspect of the present invention, in the programmable controller for connecting the second programmable controller and the personal computer, the destination reading means for reading the destination from the command message received from the personal computer. Destination determining means for determining whether the transmission destination read by the transmission destination reading means is addressed to itself or the second programmable controller; and determining whether the transmission destination read by the transmission destination determining means is addressed to itself. In this case, a response message to the command message is transmitted to the personal computer. On the other hand, if the read destination is the second programmable controller, the command message is transmitted to the second programmable controller. When the receiving the response message from the second programmable controller, since the response message received was constructed and a message transmitting means for transmitting to the personal computer, not only to communicate with a personal computer,
Communication between the second programmable controller and the personal computer can be enabled.

According to the third and fourth aspects of the present invention, in a personal computer having a tool for causing a programmable controller to perform data setting and data monitoring processing, a command message for performing the data setting and data monitoring processing is provided. Command message storage means for storing the command message, a response storage means for storing a response message from the programmable controller in response to the command message, and, when receiving an instruction from the tool that the command message should be transmitted to the programmable controller, the command message Command message forming means for forming;
When receiving from the tool an instruction that a command message for performing the data setting and the data monitoring process should be transmitted to the programmable controller, the command message is formed and stored in the command message storage. Stored in the means,
The personal computer directly reads the response message corresponding to the command message from the response storage means, forms response data indicating the contents of the response message, and outputs the response data to the tool. Communication can be performed not only with the connected first programmable controller but also with the second programmable controller connected to the personal computer via the first programmable controller. When the personal computer receives an instruction from the tool to transmit to the PLC, the personal computer stores the formed command message in the transmission buffer, and stores a response message to the command message transmitted to the PLC in the reception buffer. Even if you do not receive a response message to the command message,
A command message can be transmitted based on an instruction of the tool. Therefore, when operating the tool, the work efficiency can be improved, and it is not necessary to provide a plurality of personal computers, and the cost can be reduced.

According to a fifth aspect of the present invention, in the communication method of a programmable controller for connecting a second programmable controller and a personal computer, a destination is read from a command message received from the personal computer, and the read transmission is performed. When the destination is addressed to itself, a response message to the command message is transmitted to the personal computer. On the other hand, when the read destination is the second programmable controller, the command message is transmitted to the second programmable controller. When a response message from the second programmable controller is received, the received response message is transmitted to the personal computer. Coarsely braided not only communicate with a computer, it is possible to enable communication with the second programmable controller and personal computer.

According to a sixth aspect of the present invention, there is provided a communication method of a personal computer for transmitting a command message for performing data setting and data monitoring processing to a programmable controller. When an instruction to transmit is received, a command message is formed, the command message is stored in a transmission buffer, and then transmitted. A response message to the command message transmitted to the programmable controller is read from a reception buffer, and the read response data is read. Is formed into response data that can be understood by the tool, and the formed response data is configured to be output to the tool.
The communication can be performed not only with the directly connected first programmable controller but also with the second programmable controller connected to the personal computer via the first programmable controller, and a response message to the command message can be transmitted. Since the command message can be transmitted based on the instruction of the tool without receiving the command, the operation efficiency of the tool can be improved when the tool is operated, and the cost can be reduced by eliminating the necessity of providing a plurality of personal computers.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a programmable logic controller system according to the present invention.

FIG. 2 is a block diagram showing a configuration of a communication processing program memory stored in the communication processing program memory in FIG. 1;

FIG. 3 is an exemplary block diagram showing the configuration of the personal computer in FIG. 1;

FIG. 4 is an explanatory diagram for explaining the contents of a transmission tool correspondence table in FIG. 2;

FIG. 5 is a frame configuration diagram of a command message and a response message.

FIG. 6 is an explanatory diagram illustrating an operation of the personal computer in FIG. 1;

FIG. 7 is a protocol diagram showing a transmission procedure in the programmable logic controller system of the embodiment.

FIG. 8 is a protocol diagram showing a transmission procedure in a conventional programmable logic controller system.

FIG. 9 is a functional block diagram showing a functional configuration of the personal computer shown in FIG. 3;

FIG. 10 is an exemplary flowchart showing the entire operation of the personal computer shown in FIG. 9;

FIG. 11 is a flowchart showing details of a process 1 shown in FIG. 10;

FIG. 12 is a flowchart illustrating details of a process 2 illustrated in FIG. 10;

FIG. 13 is an exemplary view showing an example of a display screen of the personal computer in FIG. 1;

FIG. 14 is a block diagram showing an embodiment of a conventional programmable logic controller system.

FIG. 15 is a block diagram showing an embodiment of a conventional programmable logic controller system.

[Explanation of symbols]

 1, 1a Programmable controller 11 CPU unit 111 Microcomputer 112 Bus ASIC 113 Memory 114 Communication processing program storage memory 12 High function unit 121 Microcomputer 122 Bus ASIC 123 Memory 13 Communication unit 131 Microcomputer 132 Bus ASIC 133 Memory 14 System bus 2 Personal Computer 21 tool 22 OS 23 communication driver 24 transmission buffer 25 reception buffer 26 communication port 27 transmission tool correspondence table 28 reception tool correspondence table 3 tool cable

Claims (7)

[Claims] 1. A first programmable controller,
The second connected to this first programmable controller
And a personal computer connected to the first programmable controller, wherein the first programmable controller transmits a command message transmitted from the personal computer to a command addressed to itself. If the message is a message, a response message to the command message is transmitted to the personal computer, while if the command message is addressed to the second programmable controller, the response message is transmitted to the second programmable controller. A programmer transmitting a response message transmitted from a second programmable controller to the personal computer. Controller system. 2. A second programmable controller,
In a programmable controller for connecting to a personal computer, a destination reading means for reading a destination from a command message received from the personal computer, and the destination read by the destination reading means is addressed to itself. Transmission destination determining means for determining whether the destination is a programmable controller, and when the transmission destination read by the transmission destination determining means is addressed to itself, a response message to the command message is transmitted to the personal computer, while the reading is performed. When the transmission destination is the second programmable controller, the command message is transmitted to the second programmable controller, and when the response message is received from the second programmable controller, Programmable controller, wherein the received response message that includes a message transmitting means for transmitting to the personal computer. 3. A personal computer having a tool for causing a programmable controller to perform data setting and data monitoring processing, wherein: a command message storage means for storing a command message for performing the data setting and data monitoring processing; A response storage unit for storing a response message for the command message from the programmable controller; a command message forming unit for forming a command message when receiving an instruction from the tool to transmit to the programmable controller; Command from the tool to send a command message to the programmable controller for setting and monitoring data Kicking the form the command message, which is stored in the command message storing means,
A personal computer, comprising: a data forming unit that reads a response message corresponding to the command message from the response storage unit, forms response data indicating the content of the response message, and outputs the response data to the tool. 4. The data forming means receives an instruction from the tool that a command message for setting the data and monitoring the data should be transmitted to the programmable controller from the tool. 4. The personal computer according to claim 3, wherein the command is registered in the communication command management stack, and then transferred to and stored in the command message storage means. 5. A second programmable controller,
In a communication method of a programmable controller connecting to a personal computer, a destination is read from a command message received from the personal computer, and if the read destination is addressed to itself, a response message to the command message is sent to the personal computer. If the read destination is the second programmable controller, the command message is transmitted to the second programmable controller.
To the programmable controller of the second
Receiving a response message from the programmable controller according to (1), transmitting the received response message to a personal computer. 6. A communication method of a personal computer for transmitting a command message for performing data setting and data monitoring processing to a programmable controller, comprising: receiving an instruction to transmit to the programmable controller from the tool; The command message is formed, stored in a transmission buffer, and then transmitted. A response message corresponding to the command message transmitted to the programmable controller is read from a reception buffer, and the read response data is formed into response data understood by the tool. Outputting the formed response data to the tool. 7. When receiving from the tool an instruction that a command message for performing the data setting and data monitoring processing should be transmitted to the programmable controller, the command message is formed, and the command message is formed. 7. The communication method for a personal computer according to claim 6, wherein after registering in the communication command management stack, the command is transferred to and stored in the command message storage unit.