Siemens SIMATIC STEP 7 V5.2 Getting Started page 36

Creating a Program in OB1
Programming a Memory Function in Function Block Diagram
"Automatic on"
"Manual on"
If you want to see the difference between absolute and symbolic addressing, deactivate the
menu command View > Display > Symbolic Representation.
"Key_1"
"Key_2"
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 "Address
Field Width" in the "LAD/FBD" tab. Here you can set the line break between 10 and 24
characters.
4-14
"Automatic Mode"
"Green_Light"
Example:
Symbolic addressing in FBD
You can find more information under Help >
Contents in the topics "Programming Blocks,"
"Creating Logic Blocks," and "Editing FBD
Statements."
Select Network 2 and insert another
network. Select the input area again
(below the comment field).
Navigate in the Program Elements
catalog under Bit Logic until you
reach the SR element. Double-click to
insert the element.
Enter the following symbolic names for
the SR element:
Set "Automatic_On"
Reset "Manual_On"
Memory bit "Automatic_Mode"
Save the block and close the window.
Example:
Absolute addressing in FBD
STEP 7 Getting Started
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