ProSoft Technology MVI46-DFNT - Manual (Page 136)

Reference MVI46-DFNT ♦ SLC Platform
User Manual EtherNet/IP Client/Server Communication Module
Page 136 of 177 ProSoft Technology, Inc.
October 12, 2010
DDE Connection
This section discusses setting up a DDE connection to the module in order to
transfer data between the module and a DDE compliant application.
Each DDE connection requires three basic elements: Application, Topic and
Item. These three properties of a DDE link define the program providing the
connection, the topic to connect to and the item in the topic that you wish to
interface. All three are required for a connection. For this discussion, the
Application will always be RSLinx. The Topic is defined in the RSLinx OEM
release software and the Item is defined in the DDE client application where the
data is required. The link between the DDE server and the DDE client can be
established after these parameters are defined. The following illustration shows
the relationship of these elements and the facilities used in the DDE link.
1 The DDE Client application specifies the DDE link by specifying the
APPLICATION, TOPIC, and ITEM elements. For example, in Excel, enter
=RSLINX|CIP_Sample! 'ReadData[0]' into a cell.
2 RSLinx is the DDE Server: APPLICATION = RSLINX.
And
RSLinx defines the TOPIC.
This is the communication link to the DFNT module. In this example, a DDE
TOPIC is called "CIP_Sample" for the communication link to the DFNT
module.
3 The DFNT module is used to serve data to RSLinx using the EtherNet/IP
driver with explicit messaging. Database is accessed using tag names (e.g.
ReadData[0]).