Siemens SINUMERIK 840D sl Configuration Manual page 62

Programming the PLC
4.1 General information about the PLC program
Table 4-2 Organization blocks (OB)
Address Name
OB1 OB1
OB40 OB40
OB82 OB82
OB86 OB86
OB100 OB100
Table 4-3 Function blocks (FBs)
Address Icon
FB1 RUN_UP
FB2 GET
FB3 PUT
FB4 PI_SERV
FB5 GETGUD
FB7 PI_SERV2
FB9 M2N
FB10 SI_relay
FB11 SI_BrakeTest
FB29 Diagnostics
Table 4-4 Functions (FCs)
Address Icon
FC2 GP_HP
FC3 GP_PRAL
FC5 GP_DIAG
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Description
Cycle OBs are higher-level logic blocks in the program which are cy‐
clically processed and in which you can program instructions or call
additional blocks.
Hardware interrupt OBs interrupt the cyclic program processing due to
a hardware event.
Diagnostic error interrupt OBs interrupt the cyclic execution of the pro‐
gram if the diagnostic-capable module for which the diagnostic inter‐
rupt was enabled detects an error.
A rack or station failure OB is called, for example, in the event of failure
of a rack or station in the distributed I/O.
Startup OBs are processed once when the mode of the CPU switches
from STOP to RUN. After execution of the startup OB, the execution of
the cycle OB is started.
Description
The block configures and initializes the basic program, starts synchroniza‐
tion between PLC and NCK, is called in OB100 with instance DB gp_par
[DB7].
The block is used for reading NC tags.
The block is used for writing NC tags.
The block is used for starting PI services.
The block is used for reading global user data (GUD) from the NC and for
determining the GUD tag address.
The block is used for starting PI services that are defined in PI [DB16].
The block is used for switching over operating components (MCP/OP)
which are connected with one or several control modules NCU; uses the
signals from MMC [DB19].
Safety Integrated (SPL) block: Safety relay
Safety Integrated (SPL) block: Brake test
Diagnostic routines for the PLC user program with logging of signal states
and signal changes.
Description
The block processes the cyclic part of the basic program, is called at
the beginning of OB1.
The block processes the block-synchronous part of the basic program,
is called at the beginning of OB40.
The block is used to record module disruptions and failures, is called
at the beginning of the following OBs: OB82, OB83, OB86.
Configuration Manual, 12/2018, A5E46279635B AA
Called PLC basic pro‐
gram block
GP_HP [FC2]
GP_PRAL [FC3]
GP_DIAG [FC5]
GP_DIAG [FC5]
RUN_UP [FB1] with
gp_par [DB7]
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