Common Elements

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Introduction

Common Elements is the set of features that are common to all of the languages in the IEC 61131-3 standard.

Supported Common Elements

This table lists the common language elements supported by Fernhill SCADA:

Language Element Example
Comments (* IEC 61131 style comment *)
// A C++ style comment
Pragma { Use "conversion-functions.script" }
Identifier Litres
Level_1
Numeric Literals -13 0 3.14159 16#FF INT#32767
Duration Literals T#12.5s Time#-1h t#14m30s
Date and Time Literals D#2012-04-14
String Literals 'Some Text' "Wide Character Text"
Elementary Data Types BOOL INT REAL TIME STRING
Boolean Edge Detection Types BOOL R_EDGE
Generic Data Types ANY_INT ANY_REAL ANY
Derived Data Types STRUCT ... END_STRUCT, ARRAY [..] OF ...
Dynamic Data Types OBJECT, VARIANT
Variable Declaration VAR ... END_VAR
Variable Reference A B[12] C.X
Tag Reference %"Example Graphic.Tank Level"
Expressions FlowRate * 2.4
Program Unit Program ... End_Program
Class Declaration Class ... End_Class
Functions ANY_TO_STRING( 5 ), SQRT( Value )
Standard Function Blocks TON( IN:=Start, ET:=T#30s )

Further Information

IEC 61131-3 Scripts

To learn about using scripts in Fernhill SCADA.

Glossary

For the meaning of terms used in Fernhill SCADA.