Watlow LogicPro - Manual (Page 275)

Doc.# 28002-00 Rev 3.00 Watlow Anafaze 259
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Dynamic Data Exchange
Dynamic Data Exchange (DDE) is a communication protocol
designed to allow Windows applications to send and receive
data and instructions to other Windows applications.
Dynamic Data Exchange takes place between a client
application and a server application. The client initiates the
exchange by establishing a conversation with the server so
that it can send transactions (requests for data or service) to
the server. The server responds by providing the requested
data or services.
A server can have many clients at the same time, and a client
can request data from multiple servers. Applications can be
both client and server. The client terminates a conversation
when it no longer needs the server’s data or services.
How to Access a Remote Item
A DDE Server uses a three-level name to identify the data unit
that the server can exchange:
• Server name — is a string that a server application
responds to when a client attempts to establish a
conversation with a server. A client must specify this
service name to be able to establish the conversation.
Although a server may respond to many server names,
most servers respond to only one. In the case of
LogicPro, the server name is
LP_DDE .