Nematron Pointe Controller User Manual

Page 162

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Chapter 5: Developing Controller Programs

Pointe Controller User Guide

160

PROPERTY

WHAT YOU ENTER

Condition Type

Type of Condition:

Expression – Build a conditional expression using the

Build Condition

dialog.

Diag Fault Bit Test – Select an Input, Memory, or Output
tag and test to see if its

Diag Fault Bit

is set or clear.

If the condition evaluates true, then the Do/On line is followed. If
the condition evaluates false, then the Done/Off line is followed.

While/Do Loop Block Example

The decision block determines if Error_Number is greater than 0. While the
answer is yes, program flow yields to the next chart, returns to the flowline
labeled Do, and decrements the value of Error_Number before returning to the
decision block to check the value. If the value is greater than 0, flow continues to
the remainder of the current chart through the flowline labeled Done.

The LineLabels property specifies a While label that specifies the

condition, a Do label for the flowline from a condition of Error_Number
being greater than 0, and a Done label for the flowline a condition of
Error_Number being less than or equal to 0.

The Yield property specifies the program flow must continue to the next
chart while the condition is met and return to decrement and check the
value again until the condition is no longer met.

The Condition Type property is selected as Expression.

The next property defines the block’s tested expression. In this condition,
the tag, Error_Number, can be any number greater than 0.

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