Siemens SINUMERIK 840D sl Configuration Manual page 68

Programming the PLC
4.1 General information about the PLC program
This concerns the following blocks:
● All axis/channel DBs actually used
● ALMSG_DB [DB2]
● DB3 [DB3]
● DB9 [DB9]
● BAG [DB11]
● DB17 [DB17]
● MMC [DB19]
The configuring of these blocks is optional and required only when, for example, you
symbolically address them. Although warnings are issued when the configuration is compiled,
the program can be executed because of the blocks generated at runtime.
If this involves one of the blocks of the basic program that you do not require (e.g. unused axis
DB, channel DB, FB or FC), you can delete it. This reduces, for example, the time required for
loading or exporting the PLC symbols and for working with SINUMERIK archives.
68
SINUMERIK STEP 7 Toolbox V15.1
Configuration Manual, 12/2018, A5E46279635B AA