CMP

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Function Block A function block groups an algorithm and a set of private data. It has inputs and outputs. - Comparison with detailed outputs for integer inputs.

Inputs

Input	Data Type	Range	Unit	Default	Description
IN1	DINT				First value.
IN2	DINT				Second value.

Outputs

Output	Data Type	Description
EQ	BOOL	TRUE if IN1 = IN2.
GT	BOOL	TRUE if IN1 > IN2.
LT	BOOL	TRUE if IN1 < IN2.

Remarks

None

FBD Language

FFLD Language

In the FFLD language, the rung input (EN) validates the operation.
- The rung output is the result of LT (lower than) comparison).
- The comparison is executed only if EN is TRUE.

IL Language

(* MyCmp is declared as an instance of CMP function block *)
Op1: CAL MyCmp (IN1, IN2)
     LD "Ladder diagram"
Ladder logic is a method of drawing electrical logic schematics. It is now a very popular graphical language for programming Programmable Logic Controllers (PLCs). It was originally invented to describe logic made from relays. The name is based on the observation that programs in this language resemble ladders, with two vertical "rails" and a series of horizontal "rungs" between them  MyCmp.LT
     ST  bLT
     LD  MyCmp.EQ
     ST  bEQ
     LD  MyCmp.GT
     ST  bGT

ST Language

(* MyCmp is declared as an instance of CMP function block. *)
MyCMP (IN1, IN2);
bLT := MyCmp.LT;
bEQ := MyCmp.EQ;
bGT := MyCmp.GT;