Siemens SIMATIC S7 Configuration And Programming Manual page 25

Comment: You can derive the local data requirement of the OB from the program
structure. In SIMATIC Manager, select the Options > Reference Data > Display
menu command (Setting: "Program structure" selected). This shows you the local
data requirement in the path or for the individual blocks (see also STEP 7 Help).
Case 2:
Set the "F-local data" parameter to the following:
•
The maximum size of the local data of the F-CPU you are using minus 32
bytes or
•
the maximum size of the local data of the F-CPU you are using minus local
data requirements of the OB and minus local data requirements of the
standard user program A, if these are more than 32 bytes together.
Comment: You can derive the local data requirement of the OB or the standard
user program A from the program structure. In SIMATIC Manager, select the
Options > Reference Data > Display menu command (Setting: "Program
structure" selected). This shows you the local data requirement in the path or for
the individual blocks (see also STEP 7 Help).
Product Information for the S7 Distributed Safety, Configuring and Programming Manual
A5E00169432-02
F-CALL not called directly in the OB
Standard
User Program
Standard
User Program A
FB/FC
OB35 OB35
Standard
User Program B
FB/FC
Safety Program
F-run-time group
F-CALL
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