STEP 5 Operations
S5-95F
STOP Operation
The “STP” operation puts the programmable controller into the STOP mode. This can be desirable
for time-critical system circumstances or when a programmable controller error occurs.
After the statement is processed, the control program is scanned to the end, regardless of the RLO.
Afterwards the programmable controller goes into the STOP mode with the error ID “STS”. You
can restart the programmable controller with the mode selector (STOP to RUN) or with a
programmer.
Safety Note
A STOP initiated by the
”STP” operation can very easily be cancelled by means of a
programmer input (even inadvertently). A STOP produced by the ”STP” operation is
therefore
not a failsafe STOP condition (see section 18.16).
“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 programmable controller does not execute any operation 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.
•
In most cases, they can be represented in STL form only. With STEP 5 as of version V 6.0,
however, you can also program some operations in CSF (see programmer manual).
The following sections describe the supplementary operations.
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EWA 4NEB 812 6210-02
