Omron CX-PROGRAMMER V8.1, Руководство по эксплуатации

Страница: 177 / 231

152
Statement Descriptions
Section 5-5
• Multiple statements can be executed in expression_
@
. Be sure to use a
semicolon (;) delimiter between multiple statements in an expression .
• The ELSE statement can be omitted. When ELSE is omitted, no opera-
tion is executed if the result of any condition equation is false.
■
Examples
Example 1: If variable A>0 is true, variable X will be substituted with numerical
value 10.
If A>0 is false, but variable B=1, variable X will be substituted with numerical
value 1.
If A>0 is false, but variable B=2, variable X will be substituted with numerical
value 2.
If either of these conditions is met, variable X will be substituted with numeri-
cal value 0.
IF A>0 THEN X:=10;
ELSIF B=1 THEN X:=1;
ELSIF B=2 THEN X:=2;
ELSE X:=0;
END_IF;
CASE Statement
■
Summary
This statement executes an expression containing a selected integer that
matches the value from an integer equation. If the selected integer value is
not the same, either no expression or a specified expression is executed.
■
Reserved Word
CASE
■
Statement Syntax
CASE
< integer_equation >
OF
< integer_equation _ value_1 >
:
< expression_1 >
;
< integer_equation _ value_2 >
:
< expression_2 >
;
...
< integer_equation _ value_n >
:
< expression_n >
;
ELSE
< expression_m >
;
END_CASE;