Call a Method

Methods can be called from either:

  • The parent UDFB implementation.
  • Another Program through a UDFB instance.

The call methods are:

Call a Method from a Parent UDFB

Method Definition

Method Name: ValidateVelocity

Input(s):
    RequestedVelocity : LREAL;
Output(s):
    IsValid : BOOL;

Method Implementation

IsValid := RequestedVelocity <= MaxVelocity;

UDFB Implementation

ValidateVelocity(RequestedVelocity := UserVelocity);
IF ValidateVelocity. IsValid THEN
    ExecuteMove := TRUE;
END_IF;

Call a Method from a Program

Methods can be invoked from programs through a UDFB instance using this syntax: 

UDFB_Instance.MethodName(...)

UDFB Example

UDFB Name: MotionAxisController

UDFB Method Name: CalculateMoveTime

Method Definition

Input(s):
    Distance : LREAL;
    Velocity : LREAL;
Output(s):
    MoveTime : LREAL;

METHOD Implementation

MoveTime := Distance / Velocity;

Program Example

Program Variables

Inst_MotionAxisController : MotionAxisController
EstimatedTime             : LREAL

Program Implementation

Inst_MotionAxisController. CalculateMoveTime(
    Distance := 250.0, 
    Velocity := 50.0, 
    MoveTime => EstimatedTime
);

    • In this example, the method is executed through the MotionAxisController’s UDFB instance.

See Also