Structured Text Overview
ST Language Overview
Structured Text (ST) Language is an alternative PLC language defined by IEC61131-3. It is an advanced language derived from Pascal. Structured Text supports operators, control syntaxes, and functions.
| Available Characters | |
|---|---|
| Type | Description |
| Alphanumeric | A ~ Z a ~ z 0 ~ 9 |
| Symbols | + - * / = < > [ ] ( ) . , _ : ; $ # " ' |
| Additional | All ASCII control characters (ASCII: 0 ~ 31) |
| Reserved Words |
|---|
| IF, THEN, ELSEIF, ELSE, END_IF CASE, OF, END_CASE FOR, TO, BY, DO, END_FOR REPEAT, UNTIL, END_REPEAT WHILE, END_WHILE EXIT, RETURN names of PLC instructions, PLC data registers |