While/do loop block, 5 while/do loop block – Nematron Pointe Controller User Manual

Page 161

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Pointe Controller User Guide

Chapter 5: Developing Controller Programs

159

yes, program flow continues through the Flowline labeled Done. If Input_2 is less
than 20, flow yields to the next chart, then returns to the flowline Repeat to
again increment and check Input_2 until the required count is reached.

The LineLabels property specifies a Done label for the flowline followed
from a condition of Input_2 being greater than or equal to 20 and a
Repeat label for the flowline followed from a condition of Input_2 being
less than 20.

The Yield property specifies the program flow must continue to the next
chart if the condition is not met and return to increment and check the
value again until the condition is met.

The Condition Type property selects an Expression.

The next property defines the block’s tested expression. In this condition,
the tag, Input_2, can be any number greater than or equal to 20.

5.7.5 While/Do Loop Block

The While/Do Loop block represents a repetitive
process, where the block evaluates a condition at the
top of the loop until the condition evaluates to true. If
the condition is true, the blocks in the loop are
executed; if the condition is false, program flow
continues at the block immediately following the
loop.

PROPERTY

WHAT YOU ENTER

Caption

User label for the block.

Line Labels

While/Do/Done or While/On/Off as the labels for the block and
outgoing flowlines.

Yield

Yes or No to specify whether, when the condition tests false,
program flow should immediately return to top of the loop or
yield to the next listed chart. Use this option with caution, since it
essentially disables all other charts while the program executes the
loop.

A block that yields (Yes) runs all other charts in your

Chart List

after executing the blocks in the loop, then returns to the top of
the loop that yielded and retests the block’s condition. A block
that does not yield (No) continues to check the condition,
uninterrupted.

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