Siemens S7-1200 Programming Manualline page 14

2 S7-1200/1500 Innovations
2.6 Optimized blocks
Step
3.
Display of optimized and non-optimized blocks in the TIA Portal
In the two following figures the differences between an optimized and a non-
optimized instance DB can be seen.
For a global DB there are the same differences.
Figure 2-9: Optimized data block (without offset)
Figure 2-10: Non-optimized data blocks (with offset)
Table 2-5: Difference: optimized and non-optimized data block
Optimized data blocks are addressed
symbolic. No "offset" is displayed.
In optimized blocks every tag can be
declared with "Retain".
Programming Guideline for S7-1200/1500
V1.2, Entry ID: 81318674
This is where you see all blocks in the program and whether they are optimized
or not. In this overview the "Optimized block access" status can be conveniently
changed.
Note: Instance data blocks (here "Function_block_1_DB") inherit the "optimized"
status from the respective FB. This is why the "optimized" setting can only be
changed on the FB. After the compilation of the project the DB accepts the
status depending on the respective FB.
Optimized data block
Instruction
Non-optimized data block
At non-optimized blocks an "offset" is
displayed and can be used for addressing.
In non-optimized blocks only all or no tags
can be declared with "Retain".
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