Siemens SINUMERIK 840Di Function Manual page 1249

The components are parameterized by calling basic-program block FB 1 in OB 100. FB 1
stores its parameters in the associated instance DB (DB 7, symbolic name "gp_par").
Separate parameter sets are provided for each machine control panel and the handheld unit.
The input/output addresses of the user must be defined in these parameter sets. These input
and output addresses are also used in FC 19, FC 24, FC 25, FC 26 and FC 13. Addresses
for status information, MPI, PROFIBUS/Ethernet (a GD parameter set must be set for the
MPI variant of the handheld unit rather than an MPI address) must also be defined. The
default time settings for timeout and cyclic forced retriggering should not be changed.
Activation
Each component is activated either via the number of machine control panels (MCPNum
parameter) or, in the case of the handheld unit, via the HHU parameter. The MCP and HHU
connection settings are entered in FB1 parameters MCPMPI, MCPBusType or BHG,
BHGMPI.
Handheld unit (MPI)
The handheld unit addresses the MPI by means of a GD parameter set. These parameter
values must be assigned according to the handheld unit settings. However, the parameter
names on the handheld unit are the reverse of the parameter names in the basic program. In
the basic program, all *Send type parameters must be defined by the handheld unit as *Rec
type (and *Rec as *Send).
Configuring
Essentially, there are various communication mechanisms for transferring data between the
MCP/HHU and PLC. These mechanisms are characterized by the bus connection of the
MCP and HHU. In one case (Ethernet), data is transported via the CP840D. The mechanism
is parameterized completely via the MCP/HHU parameters in FB1.
In the second case, data are transferred via the PLC operating system by means of the
evaluation of SDB210 (global data) or via the PROFIBUS configuration.
The mechanism is parameterized via STEP7->Global Data or in HW Config. To allow the
basic program to access these data and implement MCP/HHU failure monitoring, the
addresses set via SDB210 (global data) must be declared in the FB1 parameters in the basic
program.
An overview of the various coupling mechanisms appears below. Mixed operation can also
be configured. If an error is detected due to a timeout monitor, an entry is made in the
diagnostic buffer of the PLC CPU (interrupts 400260 to 400262). In this case, the input
signals from the MCP or from the handheld unit (MCP1In/MCP2In or BHGIn) are initialized
with 0. If it is possible to resynchronize the PLC and MCP/HHU, communication is resumed
automatically and the error message reset by the GP.
Note
In the following tables, "(n.r.)" indicates "not relevant".
PLC Basic Program Solution Line (P3 sl)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
2.7 Structure and functions of the basic program
Detailed Description
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