Siemens SIMATIC S5-115U, User Manual

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S5-115U Manual STEP 5 Operations
STOP Operation
The "STP" operation puts the PLC into the "STOP" mode. This can be desirable for time-critical
system circumstances or when a PLC error occurs.
After the statement is processed, the control program is scanned to the end, regardless of the
RLO. Afterwards the PLC goes into the "STOP" mode with the error ID "STS". It can be restarted
with the mode selector (STOP RUN) or with a programmer.
"NOP" (No Operations)
The "NOP" operations reserve or overwrite memory locations.
Display Generation Operations
"BLD" display generation operations divide program parts into segments within a block.
"NOP" operations and display generation operations are significant only for the programmer
when representing the STEP 5 program.
The CPU does not execute any operations when these statements are processed.
8.2 Supplementary Operations
Supplementary operations extend the operations set. However, compared to basic operations,
which can be programmed in all blocks, supplementary operations have the following limitations:
• They can be programmed in function blocks only.
• They can be represented in STL form only.
Sections 8.2.1 through 8.2.11 describe the supplementary operations.
EWA 4NEB 811 6130-02b
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