Structured Text Syntax

Examples:

A := B;

You can put more than one statement in a line like this.

A := 100; B := 200; C:= 300;

Note: Statements need a semicolon at the end only.

IF statement

IF iA < 100 THEN ⬅ No semicolon

iB := 2;

ELSIF iA = 0 THEN ⬅ No semicolon

iB := 1;

ELSE ⬅ No semicolon

iB := 0;

END_IF; ⬅ Need a semicolon

FOR statement

FOR iI := 1 TO 100 BY 1 DO ⬅ No semicolon

iA[iI] = iI;

END_FOR; ⬅ Need a semicolon

For example, the variable names ‘ABC’ and ‘abc’ are handled as the same.

The following 4 literals are available.

  • 0

  • 1

  • TRUE

  • FALSE

Format:

  • Decimal: <Literal>

  • Binary: 2#<Literal>

  • Octal: 8#<Literal>

  • Hexadecimal: 16#<Literal>

Examples:

Decimal: 1234

Binary: 2#101010

Octal: 8#12

Hexadecimal: 16#1AF5

Examples:

1.234

1.234E-5

1.233999956e-005

Format:

<Data type>#<Literal>

Examples:

The following 15 data types are available.

BOOL#1

BYTE#12

WORD#123

DWORD#123

LWORD#123

SINT#123

INT#123

DINT#123

LINT#123

USINT#123

UINT#123

UDINT#123

ULINT#123

REAL#1.23

LREAL#1.23

Format:

‘<String>’

The XMC supports up to 32 characters in a STRING data.

The following $ codes are available.

  • $N (New line)

  • $R (Carriage return)

  • $T (Tab)

  • $’ (Apostrophe)

  • $$ (Dollar sign)

Examples:

‘ABC’

‘That$’s it!’

Format:

  • TIME#<d>d<h>h<m>m<s>s<ms>ms

  • T#<d>d<h>h<m>m<s>s<ms>ms

  • d (Day)

  • h (Hour)

  • m (Minute)

  • s (Second)

  • ms (Millisecond)

Note: The XMC modules don’t support ‘us’ and ‘ns’.

Examples:

TIME#1d2h3m4s5ms

T#1d2h3m4s5ms

Format:

  • DATE#<yyyy>-<mm>-<dd>

  • D#<yyyy>-<mm>-<dd>

Examples:

DATE#2023-01-01

D#2023-01-01

Format:

  • TIME_OF_DAY#<hh>:<mm>:<ss>

  • TOD#<hh>:<mm>:<ss>

Examples:

TIME_OF_DAY#12:34:45

TOD#12:34:45

Format:

  • DATE_AND_TIME#<yyyy>-<mm>-<dd>- <hh>:<mm>:<ss>

  • DT#<yyyy>-<mm>-<dd>- <hh>:<mm>:<ss>

Examples:

DATE_AND_TIME#2023-01-01-12:34:45

DT#2023-01-01-12:34:45

The following statements are handled as the same.

Two commenting methods are available in the Structured Text program.

  • Line Comment: Use ‘//’ (Two slashes) for a single line comment.

// comment

  • Block Comment: Use ‘(*’ and ‘*)’ for a single line or multiple line comment.

(* comment *)

(* comment

comment

comment *)

 

 

 

 

 

 

 

 

LM113-1