PLC Programming

IEC Operators and additional norm extending functions
Example in ST:
VAR1 := 60 >= 40;
Example in FBD:
EQ
Equal to
A Boolean operator that returns the value TRUE when the operands are equal. The operands can be
BOOL, BYTE, WORD, DWORD, SINT, USINT, INT, UINT, DINT, UDINT, REAL, LREAL, TIME,
DATE, TIME_OF_DAY, DATE_AND_TIME and STRING.
Example in IL:
LD 40
EQ 40
ST Var 1 (* Result is TRUE *)
Example in ST:
VAR1 := 40 = 40;
Example in FBD:
NE
Not equal to
A Boolean operator that returns that value TRUE when the operands are not equal. The operands can
be BOOL, BYTE, WORD, DWORD, SINT, USINT, INT, UINT, DINT, UDINT, REAL, LREAL, TIME,
DATE, TIME_OF_DAY, DATE_AND_TIME and STRING.
Example in IL:
LD 40
NE 40
ST Var 1 (* Result is FALSE *)
Example in ST:
VAR1 := 40 40;
Example in FBD:
10.6 Address Operators...
ADR
Address Function not prescribed by the standard IEC61131-3.
CoDeSys V2.3 10-13