Logic Guide - NE (Built-in Functions, Function Blocks, and Conversions)

NE

Function Name	NE (Not Equals)
Description	Outputs a True value when Input 1 is different to Input 2.
Arguments	Input 1 {ANY} Input 2 {ANY} For more information on the data types for the inputs and outputs, see Data Type Hierarchy.
Returns	Output {BOOL} The output is True only if Input 1 is different to Input 2. If Input 2 has the same value as Input 1, the NE function outputs a False value.

Function Name

NE (Not Equals)

Description

Outputs a True value when Input 1 is different to Input 2.

Arguments

Input 1 {ANY}

Input 2 {ANY}

For more information on the data types for the inputs and outputs, see Data Type Hierarchy.

Returns

Output {BOOL}

The output is True only if Input 1 is different to Input 2. If Input 2 has the same value as Input 1, the NE function outputs a False value.

Example:

Function Block Diagram - NE:

An NE function has 2 inputs (in this case, 2 constant values). Input 1 is has a value of 4 and Input 2 has a value of 2. The NE function outputs a True value as Input 1 is different to Input 2.

If Input 2 was changed to have a value of 4, the NE function would output a False value as Input 1 would be equal to Input 2. It is only when Input 1 is different to Input 2 that the NE function outputs a True value.

ST Program - NE:

The syntax for a NE function in an ST Program is:

Output := NE (Input 1, Input 2)

Where Output, Input 1 and Input 2 are defined as variables earlier in the ST program. Each input is separated by a comma and is a Boolean. The Output value is also a Boolean.