DFB Instance
A DFB instance is a copy of the DFB model (DFB type):
It uses the DFB type code (the code is not duplicated).
It creates a data zone specific to this instance, which is a copy of the parameters and variables of the DFB type. This zone is situated in the application's data area.
You must identify each DFB instance you create with a name of a maximum 32 characters, the authorized characters used depend on the choice made in the Identifiers area of the Language extensions tab in the Project Settings.
The first character must be a letter! Keywords and symbols are prohibited.
Creation of an Instance
From a DFB type, you can create as many instances as necessary; the only limitation is the size of the PLC memory.
Initial Values
The initial values of the parameters and public variables that you defined when creating the DFB type can be modified for each DFB instance.
Not all DFB parameters have an initial value.
Modification of the initial values of the elements in the DFB instances
EDT (except String type) |
String Type |
EDT |
DDT structure |
FB |
ANY_ARRAY |
IODDT |
ANY_... |
|
|---|---|---|---|---|---|---|---|---|
Inputs |
Yes |
No |
No |
No |
- |
No |
- |
No |
Input/Output |
No |
No |
No |
No |
- |
No |
No |
No |
Outputs |
Yes |
Yes |
No |
Yes |
- |
- |
- |
No |
Public variables |
Yes |
Yes |
Yes |
Yes |
- |
- |
- |
- |
Private Variables |
Yes |
Yes |
Yes |
Yes |
No |
- |
- |
- |
Modification of the initial values of the elements in the DFB type
EDT (except String type) |
String Type |
EDT |
DDT structure |
FB |
ANY_ARRAY |
IODDT |
ANY_... |
|
|---|---|---|---|---|---|---|---|---|
Inputs |
Yes |
No |
No |
No |
- |
No |
- |
No |
Input/Output |
No |
No |
No |
No |
- |
No |
No |
No |
Outputs |
Yes |
Yes |
No |
Yes |
- |
- |
- |
No |
Public variables |
Yes |
Yes |
Yes |
Yes |
- |
- |
- |
- |
Private Variables |
Yes |
Yes |
Yes |
Yes |
No |
- |
- |
- |