Command Edit Parameters

Function: The command opens the "Edit Parameters" dialog, in which you can change the constant input parameters of a function block.

Call: Menu CFC > Edit parameters, context menu > Edit parameters, click on function block field Parameter.

Requirements: A CFC editor is active. A function block is instantiated, which has VAR_INPUT CONSTANT variables in its declaration.

A function block with VAR_INPUT CONSTANT variables is indicated by TwinCAT by the word "Parameter" in the lower left corner of the function block.

Dialog Edit Parameters

Command Edit Parameters 1:

Parameter

Name of the variable

Type

Data type of the variable

Value

Click in the field to enter a value.

Initial value

Initialization value

Category

Additional information about the parameters. These values are defined by attributes and cannot be changed in this dialog

  • parameterCategory
  • parameterUnit
  • parameterMinValue
  • parameterMaxValue

Unit

Min

Max

Delete prepared parameters

The command is active if you have written a prepared value (command Debug > Write values)

After exiting the field and exiting the dialog with OK, the value changes are applied to the project.

Example of a function block with constant inputs:

FUNCTION_BLOCK FB_Sample
VAR_INPUT CONSTANT
    {attribute 'parameterCategory':='General'}
    {attribute 'parameterUnit':= 'm/s'}
    {attribute 'parameterMinValue':= '0'}
    {attribute 'parameterMaxValue':= '100'}
    nIn1 : INT;
    nIn2 : DWORD:=24354333;
    sIn3 : STRING:='abc';
END_VAR
Command Edit Parameters 2:

This functionality and the declaration of variables with the keyword VAR_INPUT CONSTANT only apply to the CFC editor. In the FBD editor, TwinCAT always shows all input parameters at the function block, irrespective of whether they are declared as VAR_INPUT or VAR_INPUT CONSTANT. Also, TwinCAT does not distinguish between text editors.

See also: