Short summary

Name	`NE`
→POU type	→function
Category	IEC-block, Compare
Conform to →IEC-standard	currently restricted (IEC demands data type `ANY_ELEMENTARY` for the inputs, hence the following data types are demanded as well: `LTIME`, `WSTRING`, `WCHAR`, `LDATE_AND_TIME`, `LTIME_OF_DAY` and `LDATE`. Currently, these data types are not supported for the block.)
Graphical interface
Available since	version 1.0.0 (for logi.CAD 3) – initial variant version 1.11.0 (for logi.CAD 3) – enhancement: data types `DATE_AND_TIME` and `TIME_OF_DAY` for `IN1`, `IN2` version 1.109.0 (for logi.CAD 3) – enhancement: data types `STRING` and `CHAR` for `IN1`, `IN2`

Functionality

The block is a comparator regarding inequality ("Not Equals to").

Enter the values at the 2 inputs, those values are to be compared. The block returns value TRUE (or an equivalent), if both values do not match – hence, if: IN1<>IN2

Bitstring values (= ANY_BIT values ; see →generic data type} are treated like unsigned →integer values by the block. This behavior is a specification according to the →IEC-standard.

Inaccuracies for floating-point numbers

Due to the internal representation of floating-point numbers (affects the data types REAL and LREAL) there might be inaccuracies when processing such values. Such inaccuracies might result in a not expected result when comparing such values.

Inputs, return value

	Identifier	→Data type	Description
Inputs:	`IN1`	`REAL`, `LREAL`, `USINT`, `UINT`, `UDINT`, `ULINT`, `SINT`, `INT`, `DINT`, `LINT`, `TIME`, `BOOL`, `BYTE`, `WORD`, `DWORD`, `LWORD`, `STRING`, `CHAR`, `DATE_AND_TIME`, `DATE` or `TIME_OF_DAY`	1st value
Inputs:	`IN2`	`REAL`, `LREAL`, `USINT`, `UINT`, `UDINT`, `ULINT`, `SINT`, `INT`, `DINT`, `LINT`, `TIME`, `BOOL`, `BYTE`, `WORD`, `DWORD`, `LWORD`, `STRING`, `CHAR`, `DATE_AND_TIME`, `DATE` or `TIME_OF_DAY`	2nd value
Return value:	–	`BOOL`

Input EN and output ENO are available when →calling the block. See "Execution control: EN, ENO" for information on input EN and output ENO.

See:

"Blocks for safe logic" whether this block is supported for developing safety-relevant applications.
"Highlighting safe logic in the FBD-editor" for the effects when using the block as a block for safe logic .

Example for usage within ST-editor

PROGRAM Test
	VAR
		result, result2 : BOOL;
	END_VAR
	result1 := NE(IN1 := 1.0, IN2 := 2.0);       (* The variable 'result1' evaluates to 'TRUE'.  *)
	result2 := NE(IN1 := 1.0, IN2 := 1.0);       (* The variable 'result2' evaluates to 'FALSE'. *)
END_PROGRAM

When creating your application within the ST-editor, enter a call of a block by typing the text as requested by the syntax or use Content Assist.