V2: Preprocessing; Brief Description - Siemens SINUMERIK 840D sl Function Manual

V2: Preprocessing

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Brief description

Preprocessing
The programs stored in the directories for standard and user cycles can be preprocessed to
reduce runtimes.
Preprocessing is activated via machine data.
Standard and user cycles are preprocessed when the power is switched on, i.e. as an internal
control function, the part program is translated (compiled) into a binary intermediate code
optimized for processing purposes.
All program errors that can be corrected by means of a compensation block are detected
during preprocessing. In addition, when the program includes branches and check structures,
a check is made to ensure that the branch destinations are present and that structures are
nested correctly.
The full scope of control functionality is available:
• Override influence
• Reactions to data and signals that are input by the PLC or the operator
• Current block display
• The programs can be processed in single block mode (SBL1 and SBL2). Block searches
can be executed. The compilation cannot be stored; it is concealed from the user and
regenerated every time the power is switched on.
Preprocessing can be used:
• To optimize the runtimes of part programs with high-level language components
(branches, check structures, motion-synchronous actions)
• CPU time intensive part programs (e.g. stock removal cycles)
• Faster processing of time-critical sections (e.g. program continuation after preprocessing
stop during rapid deletion of distance-to-go, or return stroke, or in the tool change cycle).
General information
Preprocessing standard and user cycles is possible. The processing time of part programs
can then be reduced without restricting the control functionality.
The standard and user cycles are preprocessed when machine data is set accordingly:
MD10700 $MN_PREPROCESSING_LEVEL (program preprocessing level)
Preprocessing is carried out program-specifically. It is possible to mix preprocessed part
programs and part programs interpreted in ASCII format. Preprocessing serves to reduce
incidental times.
Special Functions
Function Manual 09/2011, 6FC5397-2BP40-2BA0
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