Siemens SIMATIC STEP 7 V5.2 Getting Started page 44

Creating a Program with Function Blocks and Data Blocks
Programming an Engine to Switch On and Off
5-8
Only letters, numbers, and the underscore are permitted
characters for the names of the block parameters in the
variable declaration table.
Check whether symbolic
representation is activated.
Enter the corresponding instructions in
Network 1.
Local block variables are indicated with a # sign and
are only valid in the block.
Global variables appear in quotation marks. These
are defined in the symbol table and are valid for the
entire program.
The signal state "Automatic_Mode" is defined in
OB1 (Network 3; see page 4-10) by another SR
element and now queried in FB1.
STEP 7 Getting Started
A5E00171228-01