Condition; G Command (Action) - Siemens SINUMERIK 840D sl Function Manual

3.2.4

Condition

Execution of the action can be made dependent on the fulfillment of a condition. As long as
the synchronized action is active, the condition is checked cyclically in the interpolator clock
cycle. If no condition is specified, the action is executed cyclically in every interpolator clock
cycle.
All operations that return a truth value (TRUE/FALSE) as the result can be programmed as a
condition:
● Comparisons of system variables with constants
● Comparisons of system variables with system variables
● Comparisons of system variables with results of arithmetic operations
● Linking of comparisons through Boolean expressions
Examples
Comparisons
Program code
ID=1 WHENEVER $AA_IM[X] > $$AA_IM[Y] DO ...
ID=2 WHENEVER $AA_IM[X] > (10.5 * SIN(45)) DO ...
Boolean operations
Program code
ID=1 WHENEVER ($A_IN[1]==1) OR ($A_IN[3]==0) DO ...
See also
Reading and writing (Page 21)
Examples of conditions in synchronized actions (Page 137)
System variables for synchronized actions (Page 20)
3.2.5

G command (action)

Defined initial state
With regard to the part program sequence, synchronized actions can be executed at any time
depending on fulfillment of the condition. Therefore, it is advisable to define the required
measuring system (inch or metric) in the action part in a synchronized action. This generates
a defined initial position for the execution of the action, irrespective of the current part program
state.
Synchronized actions
Function Manual, 08/2018, 6FC5397-5BP40-6BA2
Detailed description
3.2 Components of synchronized actions
19