COMPARE: Comparing two integers

Function description

The function COMPARE performs a comparison between two integers.

The additional parameters and can be configured.

Representation in FBD

Representation:

Representation in LD

Representation:

Representation in IL

Representation:

LD Valid

COMPARE Value1, Value2, Greater_Than, Equal_Values, Less_Than, Different_Values

Representation in ST

Representation:

COMPARE(Valid, Value1, Value2, Greater_Than, Equal_Values, Less_Than, Different_Values);

Description of the parameters

The following table describes the input parameters:

Parameter	Type	Comment
Enable	BOOL	Validation input. The comparison only takes place if this input is 1.
Value1	INT	First value to compare.
Value2	INT	Second value to compare.

The following table describes the output parameters:

Parameter	Type	Comment
Greater_Than	BOOL	If Value1 > Value2 then Greater_Than = 1 Otherwise Greater_Than = 0
Equal_Values	BOOL	If Value1 = Value2 then Equal_Values = 1 Otherwise Equal_Values = 0
Less_Than	BOOL	If Value1 < Value2 then Less_Than = 1 Otherwise Less_Than = 0
Different_Values	BOOL	If Value1 ≠ Value2 then Different_Values = 1 Otherwise Different_Values = 0

EN stands for ENable; it is an optional block input. When the EN input is enabled, an ENO output is set automatically.

If EN = 0, the block is not enabled; its internal program is not executed, and ENO is set to 0.

If EN = 1, the block's internal program is run and ENO is set to 1. If an error occurs, ENO is set to 0.

If the EN input is not connected, it is set automatically to 1.

ENO

ENO stands for Error NOtification; this is the output associated with the optional input EN.

If ENO is set to 0 (because EN = 0 or in case of an execution error):

the status of the function block outputs remains the same as it was during the previous scanning cycle that executed correctly;
the output(s) of the function, as well as the procedures, are set to "0".