Assignment Statement

Help Contents


The IEC 61131-3 ST assignment statement assigns the value of an expression to a variable. The assignment statement uses this syntax:

variable-reference := expression;

The assignment target, variable-reference, can be any writable Variable Reference. The source of the assignment, expression, can be any Expression that is compatible with the assignment target.


A := B;
C[0] := C[0] + 2;
Position.Angle := ATAN( Slope );

Further Information

Structured Text

For other Structured Text (ST) statement types.

Variable Reference

To learn about variable references that can be used on the left of the := assignment operator.


To learn about expressions that can be used on the right of the := assignment operator.


For the meaning of terms used in Fernhill SCADA.