JPH086614A - Programmable controller - Google Patents

Abstract

PURPOSE:To simplify the whole user program by simplifying the communication process by the user program. CONSTITUTION:The table memory 11e of an PLC1 is stored with data transmission information tables, wherein network addresses and node addresses of other nodes, data exchange areas showing data areas to be interchanged, and execution condition information showing communication timing are registered, by the opposite communication nodes. To send data to other nodes through a network A1, the PLC1 refers to the data transmission information table stored in the table memory 11e by the CPU 11b in a communication unit 11, and sends the data in the data exchange area specified by area specification information to another node specified by node specification information when there is the node reaches a communication timing point.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a programmable controller for performing data communication with other nodes.

[0002]

2. Description of the Related Art Conventionally, in the field of FA, a network is constructed by a plurality of programmable controllers (hereinafter referred to as PLCs), and N:
Data is exchanged by N data communication or the like.

In order to perform such data communication, a user creates a ladder program for data communication and PL
It must be built into C.

[0004]

However, such a P
In data communication by LC, SEND (transmission) and REC
When data communication is performed using the same communication port using multiple commands such as V (reception), the ladder program for data communication increases in one scan, unlike the normal command processing. There is a problem that it will not fit within the time.

In other words, when two or more communication commands are used in the same communication port, it is necessary to pay attention to the timing of each communication command, so a program for exclusive control of each communication command is required. At the same time, if the number of communication commands is increased, the number of commands for timing control will further increase, and since the commands for timing control other than communication commands will occupy half of the program, the ladder program for data communication is complicated and enormous. Therefore, it does not fit within one scan time.

Therefore, the present invention has been made in view of such a problem. By omitting a program for data communication from the user program as much as possible, simplification of communication processing in the user program, and by extension, the user program. An object is to provide a programmable controller that can be simplified in its entirety.

[0007]

In order to achieve the above object, in the invention according to claim 1, in a programmable controller that performs data communication with another node via a network, another node to be a communication partner is designated. Communication information registration means in which the node specification information, the area specification information that specifies the data exchange area in the memory of the own node and the other node, and the execution condition information that specifies the communication timing with the other node are registered in advance, When the execution condition information registered in the communication information registration means is referred to, and it is determined that the execution condition is satisfied with a certain other node, the other node specified by the node designation information Data communication means for performing data communication in the data exchange area designated by the area designation information.

According to the second aspect of the invention, the first aspect is
In the programmable controller described above, the execution condition registered in the communication information registration means is that the communication timing is designated by a communication time interval.

[0009]

According to the first aspect of the present invention, node designation information designating another node as a communication partner, area designation information designating a data exchange area in the memory of the self node and the other node, and communication with the other node. Execution conditions that specify timing are registered in advance, and when it is determined that the execution conditions are satisfied by referring to each execution condition registered in advance during communication processing, the node is specified by the node specification information. Data communication of the data exchange area designated by the area designation information is performed with another node.

According to the second aspect of the invention, the execution condition is such that the communication timing is designated by the communication time interval.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a programmable controller according to the present invention will be described below with reference to the drawings.

FIG. 1 shows a connection between a PLC according to the present invention and another node.

In this figure, a PLC1 according to the present invention is connected to a PLC2 by a network A1.
2 is connected to the PLC 3 by the network A2, and the PLC 3 is connected to the PLC 4 by the network A3.

The PLC1 is connected to the network A1 and the communication unit 11, the PLC2 is connected to the network A1 and the communication unit 21, the network A2 is connected to the communication unit 22, and the PLC3 is connected to the network A2 and the communication unit a2. The PLC 4 is connected to the network A3 by the communication unit 31 and the communication unit 41, respectively. In addition, each PLC
Each of 1 to 4 has a unit such as a CPU unit (not shown) in addition to the communication unit.

FIG. 2 shows the configuration of the PLC 1 according to the present invention.

As described above, the PLC 1 includes, in addition to the communication unit 11, a user program memory unit 12 in which a user program is stored, a CPU unit 13 for executing the user program, and data for storing data such as processing results. It has a memory unit 14 and the like.

The communication unit 11 includes a communication interface (I / F) 11a connected to the network A1, a CPU 11b for performing communication processing, a system ROM 11c storing a system program for communication processing, and a work memory 11d. It has a table memory 11e and a unit I / F 11f.

The table memory 11e stores a data transmission information table in which various information for data transmission is set and a data reception information table in which various information for data reception is set, as described later.

The other PLCs 2 to 4 are also constructed similarly to the PLC 1. FIG. 3 shows a data transmission information table and a data reception information table stored in the table memory 11e.

(A) is a data transmission information table TB1
The table number (NO) is attached to each of the other nodes to which the PLC 1 transmits data, and various kinds of information for transmission are stored. That is, for each other node, the table number (NO), the other node address including the network address (NET) and the node address (NODE), and the data memory unit 14 of the own node PLC1.
, The other node reception area designation information that designates the data reception area in the data memory unit of the other node PLC, the transmission data length, and the transmission timing in communication time intervals. Stores the specified execution condition information.

(B) is a data reception information table TB2
Similarly to the data transmission information table TB1, a table number (NO) is attached to each other node that receives data from the PLC 1, and various types of information for reception are stored. That is, the table number (N
O), another node address including a network address (NET) and a node address (NODE), own node reception area designation information that designates a data reception area in the data memory unit 14 of the own node PLC 1, and another node PLC of the other node PLC. Other node transmission area designation information that designates a data transmission area in the data memory unit, transmission data length, and execution condition information that designates reception timing in communication time intervals are stored.

Next, the transmission / reception processing in the data communication unit 11 of the PLC 1 configured as described above will be described with reference to the drawings.

First, the data transmission processing by the data communication unit 11 will be described.

FIG. 4 shows a data transmission process by the data communication unit 11, and FIG. 5 shows a flow of commands and data at the time of data transmission from PLC1 to PLC2.

First, when the data transmission process is started, the CPU 11b in the communication unit 11 of the PLC 1
By referring to the data transmission information table TB1 shown in FIG. 3A stored in the table memory 11e, the execution condition information of the other node as the transmission partner is referred to and whether the execution condition is satisfied or not is determined. It is determined (step 100), and if there is another node that satisfies the execution condition (step 100 "Ye
s "), and then the data reading process in the own node is executed (step 110).

For example, time T1 has elapsed since the start of the data transmission process.
Has passed, the first registered table No. of the data transmission information table TB1 shown in FIG. 1, that is, when it is determined that the execution condition information T1 of PLC2 is established, the communication unit 11 of the own node PLC1 determines, based on the own node transmission area designation information x1 and the data length L1 as shown in FIG. Data memory unit 14
A data read command () for reading the data for the data length L1 is sent to the CPU unit 13 starting from the data address area x1. Then, the communication unit 11 extracts the data to be transmitted to the PLC 2 from the response () sent by the CPU 13 in response to the read command.

Next, the communication unit 11 judges whether or not the read processing result is normal (step 12).
0) If it is determined that the read result is normal (step 120 “Yes”), the other node PLC is made to execute the write processing of the transmission data (step 130), and then P
Wait for a response from LC2.

As shown in FIG. 5, the writing process is performed by the PLC.
1 communication unit is network address (NET) A
1 and the other node P of the network A1 based on the other node address including the node address (NODE) a1.
The data () is transmitted to LC2, and the other node PLC2 is caused to write the data starting from the data address area y1 of the data memory unit of the relevant PLC2 based on the other node reception area designating information y1. After that, the communication unit 11 of the PLC1 is connected to the C of the PLC2.
It waits for a response () from the PU unit 23 via the communication unit 21.

In PLC 1, communication unit 11 is PLC
The response () from # 2 is received, and it is determined whether or not the data writing process is normally performed in the PLC 2 (step 140). If the writing process is normally performed (step 140 “Yes”). Then, normal termination processing is performed (step 150), and the execution condition information of the data transmission information table TB1 is referred to wait for the next execution condition to be satisfied (step 100).

When the execution condition is satisfied with respect to the other other node, the communication unit 11 of the PLC 1 performs the same processes as the above steps 100 to 160 with respect to the other node with which the execution condition is satisfied, The data is transmitted to the other node.

By the way, in the above transmission process, when the result of the data read process in the own node PLC is not normal (step 120 "NO"), and in the other node PL.
If the result of the data writing process in C is not normal (step 140 “NO”), abnormal end processing is performed (step 160) and the execution conditions of other nodes are waited for (step 100). .

Next, the data receiving process in the PLC 1 will be described.

FIG. 6 shows the data reception processing in the PLC 1 in this case, and FIG. 7 shows the P reception in the PLC 1.
The reception state of data from LC2 is shown.

First, when the data receiving process is started, the CPU 11b in the communication unit 11 refers to the data reception information table TB2 shown in FIG. By referring to each execution condition information of the node, it is judged whether or not the execution condition is satisfied (step 200), and if there is another node for which the execution condition is satisfied (step 200 “Yes”), the execution condition is continued. Then, the data reading process of the other node PLC which is satisfied is executed (step 210).

For example, time T1 has elapsed since the start of the data reception process.
′ Has passed, the first registered table No. of the data reception information table TB2 shown in FIG. When 1 is determined, that is, the execution condition information T1 'of the PLC2 is established (step 200 "Yes"), the data reading process is executed for the other node PLC2 (step 210).

That is, as shown in FIG. 7, referring to the data reception information table TB2 shown in FIG. The other node PLC of the network A1 based on the other node address consisting of the network address (NET) A1 of 1 and the node address (NODE) a1
2, the read command () for the data having the transmission data length L1 ′ is sent to the data memory in accordance with the other node transmission area designation information y1 ′. On the other hand, in the PLC 2, the read command () is sent to the CPU 23 via the communication unit 21.
Is received and the response () is returned to the PLC 1 by the read command.

The PLC 1 receives the response () returned from the PLC 2 and judges whether the data reading process of the other node PLC 2 is normal (step 22).
0) If the data read process of the other node PLC2 is normal (step 220 “Yes”), then the own node reception area designation information x1 of the data reception information table TB2.
Based on ', a data write command is sent to the own node PLC1 to cause the own node PLC1 to execute a data write process (step 230).

As shown in FIG. 7, the writing process is performed by PLC1.
Communication unit 11 responds from PLC2 ()
Is received, data is read from the response, and a data write command () is sent together with the data to the local node PLC.
1 to the CPU unit 13. The CPU unit 13 writes the data from the PLC 2 based on the own node reception area designating information x1 'starting from the data address area x1' of the data memory unit, and after the data writing process is completed, the response () is communicated. Send to unit 11.

The communication unit 11 is a CPU unit 13
From the response () from (1), it is judged whether or not the result of the data write processing in the own node PLC1 is normally performed (step 240), and if the data write processing is normally performed (step 240 “Yes”). Then, normal termination processing is performed (step 250), and the execution information of the data reception information table TB2 is referred to wait for the next execution condition to be satisfied (step 200).

Then, when the execution condition is satisfied for the other other node, the communication unit 11 of the PLC 1 performs the respective processes from step 200 to 260 similar to the above for the other node for which the execution condition is satisfied, Data is received from the other node.

By the way, in the above receiving process, when the result of the data reading process in the other node PLC is not normal (step 220 "NO"), and in the own node PLC.
If the result of the data writing process in step S2 is not normal (step 240 “NO”), the abnormal end process is performed as in the case of the above transmission process (step 260), and the execution condition of another node is waited for. (Step 200).

Therefore, according to this embodiment, the data communication with the other node via the network is executed by referring to the data transmission information table and the data reception information table. Since it is not necessary to incorporate the exclusive control program and the instruction for timing control in the ladder program, the communication process in the user program can be simplified, and the entire user program can be simplified.

Further, according to the present embodiment, by reading the contents of the data transmission information table and the data reception information table, it is possible to easily grasp the actual communication execution status.

In this embodiment, the execution condition for instructing the communication timing with another node is explained by setting the communication time interval.
The designation may be made by N / OFF.

Further, in the present embodiment, the description has been made such that the other node as the communication partner is designated by the network address and the node address, and the data exchange area and the communication timing are also designated. If the node, its data exchange area, communication timing, etc. are predetermined, fix them in advance,
The user or the like may not be required to make the setting.

Further, in the present embodiment, the transmission processing and the reception processing from the PLC 1 are separately described as shown in FIGS. 4 and 6, but in the present invention, the transmission / reception table is provided with the transmission / reception designation flag and the like. Further, as shown in FIG. 8, the transmission / reception designation flag is referred to, and it is judged whether the transmission process or the reception process (step 310). Based on the judgment, the same transmission process as in FIG. Steps 320-3
45), or the same receiving process as in FIG. 6 (step 35).
0-370, 345) may be performed.

[0047]

As described above, according to the present invention, node designation information designating another node as a communication partner, area designation information designating a data exchange area in the memory of the self node and the other node, and the other Execution conditions that specify the communication timing with the node are registered in advance, and when it is determined that the execution conditions are satisfied by referring to each execution condition registered in advance during communication processing, the node specification information Since data communication of the data exchange area specified by the area specification information is performed with the other node specified by, the exclusive control program for data communication and the instruction for timing control are executed as before. It is not necessary to incorporate it in the ladder program, communication processing in the user program can be simplified, and eventually the entire user program It is possible to simplify the.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a connection between a PLC according to the present invention and another node.

FIG. 2 is an explanatory diagram showing an embodiment of a PLC according to the present invention.

3A and 3B are explanatory diagrams showing a transmission table and a reception table, respectively.

FIG. 4 is a flowchart showing a processing procedure when transmitting data.

FIG. 5 is an explanatory diagram showing a specific example of data transmission processing.

FIG. 6 is a flowchart showing a processing procedure when receiving data.

FIG. 7 is an explanatory diagram showing a specific example of data reception processing.

FIG. 8 is a flowchart showing a processing procedure when the data transmission processing and the reception processing are combined.

[Explanation of symbols]

 A1 to A3 networks 1 to 4 PLC 11 communication unit 11a communication I / F 11b CPU (data communication means) 11c system ROM 11d work memory 11e table memory (communication information registration means) 11f unit I / F 12 user program unit 13 CPU unit 14 data memory unit TB1 data transmission information table TB2 data reception information table

Claims (2)

[Claims] 1. A programmable controller for performing data communication with another node, node designation information designating another node as a communication partner, and area designation information designating a data exchange area in a memory of the self node and the memory of the other node. , And communication condition registration means in which execution condition information designating communication timing with the other node is registered in advance, and execution condition information registered in the communication information registration means is referred to, and execution condition When it is determined that the condition is satisfied, the data communication means performs data communication of the data exchange area designated by the area designation information with another node designated by the node designation information. A programmable controller characterized in that 2. The programmable controller according to claim 1, wherein the execution condition registered in the communication information registration means specifies a communication timing by a communication time interval.