Siemens SIMATIC STEP 7 V5.2 Getting Started page 29

Programming a Memory Function in Ladder Logic
If you want to see the difference between absolute and symbolic addressing, deactivate the
menu command View > Display > Symbolic Representation.
You can change the line break for symbolic addressing in the LAD/STL/FBD program
window by using the menu command Options > Customize and then selecting "Width of
address field" in the "LAD/FBD" tab. Here you can set the line break between 10 and 24
characters.
STEP 7 Getting Started
A5E00171228-01
Select Network 2 and insert another
network.
Select the current path again.
Navigate in the Program Elements
catalog under Bit Logic until you
reach the SR element. Double-click to
insert the element.
Insert a normally open contact in front
of each of the inputs S and R.
Enter the following symbolic names for
the SR element:
Upper contact "Automatic_On"
Lower contact "Manual_On"
SR element "Automatic_Mode"
Save the block and close the window.
Example:
Symbolic addressing in LAD
Example:
Absolute addressing in LAD
You can find more information under Help >
Contents in the topics "Programming Blocks,"
"Creating Logic Blocks," and "Editing Ladder
Instructions."
Creating a Program in OB1
4-7