How do i, Use dde with the server, How to use dde with the server – IDEC WindSRV User Manual

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Result =((Raw_value/32000) * Span_egu) + Lo_egu.

Read Algorithm Variables

Lo_egu - the database block's low engineering value.
Span_egu - the span of the engineering values.
Raw_value - the value stored in the field device's register.
Result - the scaled value stored in the database block.

Write Algorithm

Writes to a 16-bit register using the following algorithm:

Result =(((InputData - Lo_egu)/Span_egu) * 32000) + .5.

Write Algorithm Variables

Lo_egu - the low engineering value.
Span_egu - the span of the engineering values.
InputData - the database block's current value.
Result - the value sent to the process hardware.

How Do I...

For descriptive information on how to complete the follow actions, select a link from the list below.

Use DDE with the Server

Use Net DDE Across a Network

Use Dynamic Tag Addressing

Process Array Data

Create and Use an Alias

Use an Alias to Optimize a Project

Optimize the Server Project

Select the Correct Network Cable

Use Ethernet Encapsulation

Resolve Comm Issues When the DNS/DHCP Device Connected to the Server is Power Cycled

How To... Use DDE with the Server

Using DDE in Your Application

Dynamic Data Exchange (DDE) is a Microsoft communications protocol that provides a method for exchanging data
between applications running on a Windows operating system. The DDE client program opens a channel to the DDE
server application and requests item data using a hierarchy of the Application (Service) name, Topic name and
Item name.

Example 1: Accessing a Register Locally (Using the Default Topic)

Syntax: <application>|<topic>!<item>

Example: MyDDE|_ddedata!Modbus.PLC1.40001

Where:
application: DDE service name
topic: _ddedata (Default topic for all DDE data not using an Alias Map entry)
item: Modbus.PLC1.40001

Example 2: Accessing a Register Locally (Using an Alias Name as a Topic)

Syntax: <application>|<topic>!<item>

Example: MyDDE|ModPLC1!40001

Where:
application: DDE service name
topic: ModPLC1 (Topic now using Alias Map entry)
item: 40001

See Also:

DDE Options

FastDDE & SuiteLink

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