Siemens SINUMERIK 840Di Function Manual page 1412

Detailed Description
2.12 Block descriptions
If the MCP fails, the signals it supplies are set to zero.
Multiple calls of FC 19, FC24, FC 25, and even FC 26 are permitted within the same PLC
cycle. In this case, the first call in the cycle activates the LED displays. Moreover, all actions
of the parameterized block are executed in the first call. In the following calls, only a reduced
level of processing of the channel and mode group interface takes place. The geometry axes
are supplied with directional data only in the first block call in the cycle.
The second machine control panel can be processed if parameter ModeGroupNo has been
increased by B#16#10. When parameterizing, the HHU number is contained in the lower
nibble (lower 4 bits).
BAGNo = 0 or B#16#10 means that the mode group signals are not processed.
ChanNo = 0 means that the channel signals are not processed.
The INC selections are transferred to the mode group interface. The activation for this
command is performed by this block once after power-up via DB10.DBX 57.0. Furthermore,
two machine control panels can be handled in parallel by this block. The block call for the
2nd machine control panel in the OB1 cycle must come after the call for the 1st MCP.
Support for two MCPs is provided in the control panel blocks up to certain limits (support is
not provided as standard for mutual interlocking of axis selections with identical assignments
on two MCPs).
Flexible axis configuration
It is possible to be flexible in the assignment of axis selections or direction keys for machine
axis numbers.
Better support is now provided by the MCP blocks for the use of two MCPs, which are to run
in parallel, in particular for an application using two channels and two mode groups. Note
that the axis-numbers are also specified in the parameterized mode group number of the
MCP block in the axis tables of the relevant MCP.
To afford this flexibility, tables for axis numbers are stored in DB 10. For the first machine
control panel (MCP), the table starts at byte 8 (symbolic name: MCP1AxisTbl[1..22]) and at
byte 32 for the second MCP (symbolic name: MCP2AxisTbl[1..22]) for the second MCP. The
machine axis numbers must be entered byte by byte here.
It is permissible to enter a value of 0 in the axis table. Checks are not made to find
impermissible axis numbers, meaning that false entries can lead to a PLC Stop.
For FC 19, the maximum possible number of axis selections can also be restricted. This limit
is set for the appropriate MCP in DB10.DBW30 (symbolic name: MCP1MaxAxis) or
DB10.DBW54 (symbolic name: MCP2MaxAxis). The default setting is 0, corresponding to
the maximum number of configured axes. The axis numbers and the limit can also be
adapted dynamically. Afterwards, a new axis must be selected on FC 19.
Axis numbers may not be switched over while the axes are traversing the relevant direction
keys.
The compatibility mode is preset with axis numbers 1 to 9 for both MCPs and restricted to
the configured number of axes.
2-218
PLC Basic Program Solution Line (P3 sl)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0