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Defining timers in logic memory – Nematron Pointe Controller User Manual

Page 119

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Pointe Controller User Guide

Chapter 5: Developing Controller Programs

117

6. If you want to set an initial value (i.e., the value to which the String will

be set on program startup), click Modify and enter the value.

7. Repeat steps 3 through 6 as needed.

8. When finished, close the editor window. You will be prompted to save

your changes.

5.4.4 Defining timers in Logic Memory

A Timer is a special data structure that is used to count real time in milliseconds,
based on the Pointe Controller’s internal clock rather than on the project’s

scan

cycle

. Up to 2048 Timers are pre-allocated in Logic Memory, and you can use any

one of them once you have given it a name.

Each Timer is assigned a Preset value (in milliseconds), either when it is first
defined or later by using a function block. The Timer can then be started and
stopped as needed by the logic flow, and when it reaches its Preset it sets a “done
bit that can be read.

For more information on using Timers, see

Timer Commands

(for Flow Charts) on

page 303 or

Timer and Counter blocks

(for Ladder Diagrams) on page 350.

To define new Timers:

1. In the

Project Workspace pane

, double-click on Logic Memory to expand

the hierarchy.

2. Select and open the Timers data table. The Timers editor window will

appear.