Siemens SINUMERIK 840D sl Function Manual page 531

NC/PLC interface signals
In the case of an associated user-defined auxiliary function, the same signals are output to
the NC/PLC interface as for the corresponding predefined auxiliary function. To distinguish
which auxiliary function has actually been programmed, the value of the user-defined
auxiliary function ("value" parameter) is output as the value of the auxiliary function. This
means it is possible to distinguish between predefined and user-defined auxiliary functions in
the PLC user program.
Note
A change in the following machine data may require corresponding adjustment of the PLC
user program:
• MD22254 $MC_AUXFU_ASSOC_M0_VALUE (additional M function for program stop)
• MD22256 $MC_AUXFU_ASSOC_M1_VALUE (additional M function for conditional stop)
Specific NC/PLC interface signals
The following specific NC/PLC interface signals are available:
• DB21, ... DBX318.5 (associated M00/M01 active) feedback signal
• DB21, ... DBX30.5 (activate associated M01) activation signal
Example
Associating the user-defined auxiliary function M123 with M0:
MD22254 $MC_AUXFU_ASSOC_M0_VALUE = 123 (additional M function for program stop)
The user-defined auxiliary function M123 thus has the same functionality as M0 (stop).
Constraints
Please note the following boundary conditions:
• A user-defined auxiliary function may not be multiply associated.
• Predefined auxiliary functions (e.g. M3, M4, M5 etc.) must not be associated.
Basic logic functions: Auxiliary Function Output to PLC (H2)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Detailed description
2.9 Associated auxiliary functions
43