Description

Function description

The FORCE_BIT function allows to force a boolean variable of type EBOOL to 0 or 1. If the variable is already forced to 0 (or to 1), this EF can change the forced value to 1 (or to 0) without needing to call the UNFORCE_BIT EF before.

The additional parameters EN and ENO can be configured.

NOTE: The behaviour of FORCE_BIT function depends on the state of %S79 system bit.

NOTE: The behavior of forced outputs (%M) is different for Modsoft/NxT/Concept and Control Expert.

With Modsoft/NxT/Concept you cannot force outputs when the Memory Protect switch of the Quantum CPU is set to the "On" position.

With Control Expert you can force outputs even when the Memory Protect switch of the Quantum CPU is set to the "On" position.
With Modsoft/NxT/Concept, forced outputs maintain their values following to a cold start.

With Control Expert, forced outputs lose their values following to a cold start.

WARNING

UNEXPECTED VARIABLE BEHAVIOR

Ensure that the behavior of the forced outputs is consistent with the application.

Failure to follow these instructions can result in death, serious injury, or equipment damage.

Representation in LD

Representation in FBD

Representation in IL

Representation:

CAL FORCE_BIT ( VARIABLE := Variable,VALUE := Value)

Representation in ST

Representation:

FORCE_BIT ( VARIABLE := Variable,VALUE := Value)

Description of parameters

The following table describes the input parameters:

Parameter	Type	Comment
VARIABLE	`EBOOL`	Variable to be forced, should be a located EBOOL.
VALUE	`BOOL`	Forcing value