Siemens SINUMERIK 840D sl Programming Manual page 303

Note
MEASA cannot be programmed in synchronized actions. As an alternative, MEAWA plus the
deletion of distance-to-go can be programmed as a synchronized action.
If the measuring task with MEAWA is started from synchronized actions, the measured values
will only be available in the machine coordinate system.
Measurement results for MEASA, MEAWA
The results of measurements are available under the following system variables:
● In the machine coordinate system:
$AA_MM1[<axis>]
...
$AA_MM4[<axis>]
● In the workpiece coordinate system:
$AA_WM1[<axis>]
...
$AA_WM4[<axis>]
Note
No internal preprocessing stop is generated when these variables are read. A preprocessing
stop must be programmed with STOPRE at the appropriate position in the program. False
values will otherwise be read in.
Job Planning
Programming Manual, 06/2009, 6FC5398-2BP20-0BA0
4.8 Extended measuring function (MEASA, MEAWA, MEAC) (option)
Measured value of programmed measuring system on trigger
event 1
...
Measured value of programmed measuring system on trigger
event 4
Measured value of programmed measuring system on trigger
event 1
...
Measured value of programmed measuring system on trigger
event 4
Special motion commands
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