Nematron Pointe Controller - Manual (Page 115)

Pointe Controller User Guide Chapter 5: Developing Controller Programs
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5.4 Defining Variables in Logic Memory
In PointeControl, Logic Memory is the database of all tags, variables, and data
structures used in your program. Logic Memory is globally accessible, allowing all
Flow Charts, Ladder Diagrams, and I/O points to communicate freely and
continuously with each other using the same data in common. For example, a
Flow Chart can read a variable that was set by a Ladder Diagram, or a Flow Chart
and a Ladder Diagram can both monitor an input tag that is associated with one
of the controller’s
I/O points , and so on.
Logic Memory supports the following data types:
An Input tag is a bit, integer, or real number variable that is associated
with a Pointe Controller input channel.
A Memory tag is a bit, integer, or real number variable that is stored in
temporary memory.
An Output tag is a bit, integer, or real number variable that is associated
with a Pointe Controller output channel.
A String is used to store ASCII text. Strings can also be associated with
operator panel display lines.
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 .
As you define tags and variables in Logic Memory, keep in mind which tags you
will need to associate with to the Pointe Controller’s I/O points and which you will
need to facilitate your program’s internal logic flow.
NOTE: All tags and variables are defined using plaintext names or “aliases.” DRVs
and wire labels are not used in PointeControl.
5.4.1 Java reserved words
Since your PointeControl project will ultimately be compiled into Java classes, you
cannot use any of Java’s “reserved words as aliases in Logic Memory. Reserved
words are terms that have their own inherent functions within the programming
language itself and therefore can conflict with similarly named variables.
PointeControl will automatically check for conflicts whenever you attempt to
compile your project , but it is better to avoid using reserved words when defining
your variables in the first place.
Java’s reserved words include:
abstract
boolean
default
do
goto
if
operator
outer
synchronized
this