Siemens SINUMERIK 840D sl Function Manual page 535

Behavior regarding: M19 (position spindle)
After block completion, the last spindle positioning command programmed with M19 is
always carried out, even if other spindle-specific auxiliary functions are programmed
between the parts program with M19 and the destination block. Setting the necessary spindle
enables must therefore be derived from the interface signals of the traverse commands in
the PLC user program:
DB31, ... DBX64.6 / 64.7 (traverse command minus / plus)
In this case, the spindle-specific auxiliary functions M3, M4, M5 are not suitable because they
might not be output to the PLC after the spindle positioning.
For detailed information on the block search, please refer to:
References::
/FB1/Function Manual, Basic Functions; Mode Group, Channel, Program Operation (K1)
2.12.2 Output suppression of spindle-specific auxiliary functions
Function
For example, with a tool change it may be necessary not to output the spindle-specific
auxiliary functions collected during the block search in action blocks but to delay output, for
example, until after a tool change.
This requires suppression of automatic output of the spindle-specific auxiliary functions after
block search. Output can then be performed manually later by overstoring or by an ASUB.
Parameterization
Suppression of automatic output of the spindle-specific auxiliary functions after block search
is performed via machine data:
MD11450 $MN_SEARCH_RUN_MODE, bit 2 (search parameterization)
Bit
2
Basic logic functions: Auxiliary Function Output to PLC (H2)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Value Meaning
0 Output of the spindle-specific auxiliary functions is performed in the action blocks
1 Output of the auxiliary functions is suppressed in the action blocks.
Detailed description
2.12 Block search
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