Siemens SINUMERIK 840Di Function Manual page 1161

General
Blocks FC 19 (M version), FC 24 (slim-line version), FC 25 (T version) and FC 26 (HPU/HT6
version) transfer the machine control panel to and from the application interface. In the input
parameters, "ModeGroupNo" selects the mode group to be processed by the block. The
"ModeGroupNo" parameter also selects the number of the machine control panel. "ChanNo"
selects the channel to be processed. The "SpindleIFNo" parameter defines the axis interface
of the spindle. The spindle override is transferred to this spindle interface. The parameters
are checked for errors. Output parameters "FeedHold" and "SpindleHold" are generated
from the 4 feed/spindle disable and feed/spindle enable keys and are returned with "logical
1" for disable. Information for the next cycle is stored in DB8, bytes 0 to 3 or bytes 62 to 65,
depending on the machine control panel number. This information is the edge trigger flag,
feed value and selected axis number. The blocks are provided with user data via the pointer
parameters in DB 7 MCP1In and MCP1Out (MCP2In and MCP2Out). The pointers are
addressed indirectly via a further pointer from the VAR section of DB7 in order to avoid
absolute addressing. This additional pointer is determined symbolically in FB1.
Block descriptions
All four blocks have a similar structure. The blocks are organized into separate sections for
individual subtasks.
In the input network, various parameters are copied into local variables. The machine control
signals (user data for input/output area) are also copied between locations using the various
pointers in DB 7 (gp_par). These local variables are handled in the block for reasons of
efficiency. Some values are initialized for the startup.
The MCS/WCS switchover with edge evaluation, axis selections, direction keys and rapid
traverse overlay are determined in Network Global_in for further processing in the block.
Userspecific modifications should be made to this Section of the program. The userspecific
modifications will usually mainly involve axis selections.
Only the keyswitch information is copied in Network NC.
The mode group network transfers the modes of the keys as dynamic signals to the NCK. If
the mode group number is 0, this network is not processed. If the number is too large,
message 401901 or 402501 is output and the control switches to Stop mode.
In the channel network, INCREMENT selections of the geo axes are transferred to the
interface of all geo axes dynamically by the pushbutton switches (up to SW 4). The NC Start,
Stop, Reset and SingleBlock functions are activated by corresponding checkback signals.
The direction keys of the geometry axes are supplied if a corresponding preselection is
made, otherwise they are cleared. If the channel number is 0, this network is not processed.
If the number is too large, message 401902 or 402502 is output and the control switches to
Stop mode.
The spindle network transfers the spindle override into the interface configured via
SpindleIFNo.
The axis network transfers the feedrate override to the selected axis interface. The direction
keys are assigned to the selected axis/spindle. If an axis was selected previously, the
direction information is set to 0. The INC checkback of the selected axis is displayed.
Power Line Basic PLC Program (P3)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Detailed description
2.12 Block descriptions
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