Siemens SINUMERIK 840D sl Function Manual page 884

Rotary Axes (R2)
Programming rotary axes
Figure 13-6
Block-search response
After a block search with calculation, the collected modulo-conversion search position can be
scanned via the
$AC_RETPOINT
system variable.
This system variable returns the position converted to modulo.
Supplementary conditions for ASUB after block search with calculation:
In this instance, as well as with the cross-channel block-search tool SERUPRO, the modulo
conversion simulated in the block search must be performed in the part program.
Modulo rotary axis with/without working-area limitation
The PLC can set interface signal
DB31, ... DBX12.4
for dynamic activation/deactivation of the working-area limitation/software limit switches
associated with a modulo rotary axis (similar to rotary axes).
The NC feeds back the current status of the traversing-range limitation via interface signal
DB31, ... DBX74.4.
The monitoring function is activated if interface signal
DB31, ... ; DBX 12.4
has been set by the PLC.
The M/H function which causes the PLC to set the interface signal must be followed by
STOPRE, to ensure through synchronization that only the blocks after switchover are
monitored.
884
Examples of DC programming
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Extended Functions