Sample Programming For Cip Connectionless (Ucmm) Message Communications - Omron Sysmac NJ-series User Manual

8 CIP Message Communications
Use the following procedure to create a variable in the variable table.
1
Select the Array Check Box.
2
Specify the element first number, the element last number, and the data type.
Example: UINT Array
Variable table
Variable name
Specify the array element first
number and last number.
 CIP Communications Instructions That Use Array Variables
Instruction
CIPRead
CIPWrite
CIPSend
8-2-7 Sample Programming for CIP Connectionless (UCMM) Message
Communications
This sample uses CIP UCMM messages to write a variable, read a variable, and send a message. The
Controllers are connected to an EtherNet/IP network. The IP address of the remote node is
192.168.250.2. The following procedure is used.
1
The CIPUCMMWrite instruction is used to write the value of a variable at a remote node. The
variable name at the remote node is WritingDat and the contents of the WriteDat is written to it.
WritingDat must be defined as a global variable at the remote node and the Network Publish
attribute must be set.
2
The CIPUCMMRead instruction is used to read the value of a variable at a remote node. The
value of the variable OriginalDat at the other node is read and the read value is stored in the
ReadDat variable. OriginalDat must be defined as a global variable at the remote node and the
Network Publish attribute must be set.
3
The CIPUCMMSend instruction is used to send an explicit message to a remote node. The con-
tents of the message is to read identity information (product name). The class ID, instance ID,
attribute ID, and service code are as follows. The response data is stored in the RespDat vari-
able.
Class ID
Instance ID
Attribute ID
Service code
8-22
Array
Input variable
---
SrcDat (Write Data)
ServiceDat (Command
Data)
Item Value
1
1
7
16#0E
NJ/NX-series CPU Unit Built-in EtherNet/IP Port User's Manual (W506)
Data type
Specifies the data type.
Structure variable name
In-out variable
---
---
RespServiceDat (Response
Data)
Output variable
DstDat (Read Data)
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