Siemens SINUMERIK 840D sl Function Manual page 993

Even if the selection for the auxiliary function groups (T, H, DL) is made using interrupt control,
only one interrupt can be processed by the user program for the selected functions.
A bit is set channelspecifically in the local data "GP_AuxFunction" for the user program (if
"GP_AuxFunction[1]" is set, then an auxiliary function is available for the 1st channel).
In the related channel-DB the change signal and the function value are available for the user.
The request signal of this interrupt-driven function is reset to zero in the cyclic basic program
section after the execution of at least one full OB1 cycle (max. approx. two OB1 cycles).
Tool change
With the tool-management option, the tool-change command for revolver and the tool change
in the spindle is supported by an interrupt. The local data bit "GP_TM" in OB40 is set for this
purpose. The PLC user program can thus check the tool management DB (DB72 or DB73) for
the tool change function and initiate the tool change operation.
Position reached
In the bit structure, "GP_InPosition" of the local data of OB40 is specific to the machine axis
(each bit corresponds to an axis/spindle, e.g. GP_InPosition[5] corresponds to axis 5).
If a function has been activated via FC18 (spindle control, positioning axis, indexing axis) for
an axis or spindle, the associated "GP_InPosition" bit can be used to implement instantaneous
evaluation of the "InPos" signal of the FCs listed above. This feature can be used, for example,
to obtain immediate activation of clamps for an indexing axis.
Declaration
FUNCTION FC3: VOID
// no parameters
Call example
As far as the time is concerned, the basic program must be executed before other interrupt-
driven user programs. It is, therefore, called first in OB40.
The following example contains the standard declarations for OB40 and the call for the basic
program.
ORGANIZATION_BLOCK OB40
VAR_TEMP
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
OB40_EV_CLASS :
OB40_STRT_INF :
OB40_PRIORITY :
OB40_OB_NUMBR :
OB40_RESERVED_1 :
OB40_MDL_ID :
OB40_MDL_ADDR :
OB40_POINT_ADDR :
P3: Basic PLC program for SINUMERIK 840D sl
BYTE ;
BYTE ;
BYTE ;
BYTE ;
BYTE ;
BYTE ;
INT;
DWORD;
13.17 Block descriptions
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