REAL_TO_BOOL

The REAL_TO_BOOL block converts a REAL value to BOOL.

Ladder Representation

Variable Type	Name	Data Type	Description
VAR_INPUT	EN	BOOL	Block enable.
VAR_INPUT	Value	REAL	REAL value.
VAR_OUTPUT	ENO	BOOL	End of operation.
VAR_OUTPUT	Result	BOOL	BOOL value.

When EN is TRUE, the block interprets Value as a REAL value, converts it to BOOL, and stores the result in Result.

When EN is FALSE, Result remains unchanged.

The ENO output passes the EN state to the next Ladder block after the operation is finished.

Machine Epsilon

Values very close to the machine epsilon can be interpreted as FALSE in the final result.

REAL_TO_BOOL execution flowchart

The Ladder examples convert VALUE from REAL to BOOL, store the final value in RESULT, and activate ENO when the block finishes successfully.

REAL_TO_BOOL Ladder example

REAL_TO_BOOL Ladder example result

REAL_TO_BOOL additional Ladder example

The following Structured Text code applies the same logic shown in the Ladder example.

Structured Text
VAR
    VALUE : REAL := 0.008;
    RESULT : BOOL;
END_VAR

RESULT := FB_REAL_TO_BOOL(EN:=DI1, Value:=VALUE, ENO=>DO1);