Siemens SINUMERIK 840D sl Function Manual page 845

User program
The user PLC program merely needs to call the basic program block FC10 with appropriate
parameter settings in the cyclic program section and set or reset the bit fields in DB2. All further
necessary measures are implemented by the basic program and HMI.
Figure 13-7
Extensions of the PLC alarms via block FC10
The FB1 parameter "ExtendAlMsg" selects the PLC alarm mechanism.
If "ExtendAlMsg:= FALSE" the earlier process of the FC10 with the DB2 is active as bit array
data block. The known restrictions regarding the number of channels and axes are applicable.
On the other hand, in case of "ExtendAlMsg:= TRUE" the extension of the FC10 becomes
active. DB2 and DB3 are created just as before. The user must set or reset the bits in DB2.
The parameter setting via message and alarm and a parameter setting of the numeric value
of the 2nd decade of the user alarms are contained in DB5.
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
Acquisition and signaling of PLC events
P3: Basic PLC program for SINUMERIK 840D sl
13.9 Interface structure
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