Siemens sinumerik 840d Programming Manual page 61

04.00
1
840D 840D
NCU 571 NCU 572
NCU 573
Supplementary conditions
Blocks with check structure elements cannot be
suppressed. Labels may not be used in blocks of
this type.
Check structures are processed interpretively. When
a loop end is detected, a search is made for the loop
beginning, allowing for the check structures found in
the process.
For this reason, the block structure of a program is
not checked completely in interpreter mode.
It is not generally advisable to use a mixture of
check structures and program branches.
A check can be made to ensure that check
structures are nested correctly when cycles are
preprocessed.
Check structures may only be inserted in the
statement section of a program. Definitions in the
program header may not be executed conditionally
or repeatedly.
It is not permissible to superimpose macros on
vocabulary words for check structures or on branch
destinations. No such check is made when the
macro is defined.
 Siemens AG 2000. All rights reserved
SINUMERIK 840D/840Di/810D/FM-NC Programming Guide Advanced (PGA) − 04.00 Edition
FM-NC 810D 840Di
Flexible NC programming
1.12 Control structures
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