Basic Modules For Conditions And Actions - Siemens sinumerik 840d Programming Manual

Motion-Synchronous Action
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10.2 Basic modules for conditions and actions

840 D 840D
NCU 571 NCU 572
NCU 573
10.2 Basic modules for conditions and actions
Real-time variables
Real-time variables are evaluated and written in the
interpolation cycle.
The real-time variables are
• $A... , main run variable,
• $V... , servo variable.
To identify them specially, these variables can be
programmed with $$:
$AA_IM[X] is equivalent to $$AA_IM[X].
Setting and machine data must be identified with $$
when evaluation/assignment takes place in the
interpolation cycle.
A list of variables is given in the Appendix.
Calculations in real time
Calculations in real time are restricted to the data types
INT, REAL and BOOL.
Real-time expressions are calculations that can be
executed in interpolation cycles that can be used in
the condition and the action for assignment to NC
addresses and variables.
• Comparisons
In conditions, variables or partial expressions of
the same data type can be compared. The result
is always of data type BOOL.
All the usual comparison operators are
permissible (==, <>, <, >, <=, >=).
• Boolean operators
Variables, constants and comparisons can be
gated using the usual Boolean operators (NOT,
AND, OR, XOR)
10-350
FM-NC 810D 840Di
SINUMERIK 840D/840Di/810D/FM-NC Programming Guide Advanced (PGA) – 04.00 Edition
12.97
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