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Item point naming, Finding the available item names, Excel spreadsheet dde sample – Watlow LogicPro User Manual

Page 280

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Chapter 17: Dynamic Data Exchange

LogicPro User’s Guide

264

Watlow Anafaze

Doc.# 28002-00 Rev 3.00

NOTE!

Once the topic is deleted, it cannot be recovered.
Make sure you really want to delete the topic be-
fore you do so.

Item Point Naming

In LogicPro, an item is a symbolically named Variable. Items
can be read or written to through the LogicPro DDE server
with the exception of real world I/O points. If the values of
these points are changed by the LogicPro DDE Server, the
scan loop of the controller will overwrite these changes.

Finding The Available Item Names

Once a topic is opened, you can acquire a list of available
symbolic names for that application Program by selecting the

Topic Info

menu then

Variables

. The

Variables List

dialog box appears with a complete listing of available names,
including Real-time values.

Excel Spreadsheet DDE Sample

In this example, Excel is used with the LogicPro DDE Server.
To run this example, you need:

LogicPro v2.0 or greater.

LogicPro DDE Server.

Microsoft Excel v4.0 or greater (v5.0 is strongly
recommended).

The Program, Example 1, shown in Figure 17.1 on page 265,
continuously increments six timers.