Omron CS1-H Series, Руководство по эксплуатации

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Structured Text (ST Language) Specifications Appendix B
Operator Priority
• Consider the operator priority in the structured text syntax, or enclose operations requiring priority in
parentheses.
Example: AND takes priority over OR. Therefore, in the example X OR Y AND Z, priority will be given to Y
AND Z.
CX-Programmer’s ST Input Screen Display
Text Display Color
The CX-Programmer automatically displays text in the following colors when it is input or pasted in the ST Input
Screen.
• Text keywords (reserved words): Blue
• Comments: Green
• Errors: Red
• Other: Black
Changing Fonts
To change font sizes or display colors, select Tools - Options - Display , and then click the ST Font Button.
The font name, font size (default is 8 point), and color can be changed.
Statements
Statement Function Example
End of statement Ends the statement ;
Comment All text between (* and *) is treated as a
comment. (* comment *)
Assignment Substitutes the results of the expres-
sion, variable, or value on the right for
the variable on the left. A:=B;
IF, THEN, ELSIF, ELSE, END_IF Evaluates an expression when the con-
dition for it is true. IF ( condition_1 ) THEN
( expression 1 );
ELSIF ( condition_2 ) THEN
( expression 2 );
ELSE
( expression 3 );
END_IF;
CASE, ELSE, END_CASE Evaluates an express based on the
value of a variable. CASE ( variable ) OF
1: ( expression 1 );
2: ( expression 2 );
3: ( expression 3 );
ELSE
( expression 4 );
END_CASE;
FOR, TO, BY, DO, END_FOR Repeatedly evaluates an expression
according to the initial value, final
value, and increment. FOR ( identifier ) := ( initial_value ) TO
( final_value ) BY ( increment ) DO
( expression );
END_FOR;
WHILE, DO, END_WHILE Repeatedly evaluates an expression as
long as a condition is true. WHILE ( condition ) DO
( expression);
END_WHILE;
REPEAT, UNTIL, END_REPEAT Repeatedly evaluates an expression
until a condition is true.
REPEAT
( expression);
UNTIL ( condition )
END_REPEAT;