Siemens SIMATIC S7 System Manual page 35

You can capture up to 10 block states in your project. Block states are still accessible after
the project has been saved. However, closing the project removes any captured block
states.
The ability to capture and restore the state of the program block is more powerful than the
"Undo" function because the block state transcends the "Save" function.
S7-1200 Programmable controller
System Manual, 11/2011, A5E02486680-05
Click the "Capture block state" button to save the current state of the user program.
After you capture a state of the user program, the program block displays a "Block
state" icon.
Click the "Restore block state" button to restore the program block to the block state
that was captured.
Click the "Delete block state" button to remove the block state that was captured.
95BSTEP 7 programming software
2.3 Easy-to-use tools
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