The Shared Memory
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Operating Manual ProNumeric XCI 600 Version 07/16
If the shared-memory version of the operating software and the version in
the PLC do not correspond, an error message is entered in the error
memory when the PLC starts. This error message is displayed in the
Schleicher Dialog as follows.
Figure 86:
Display of the shared
memory error message
in the Schleicher
Dialog
If such an error message appears, the PLC project must be corrected by
inserting the data types and variables for the appropriate shared memory
version. Next, the PLC project must be recompiled and transferred to the
controller.
10.2
Variables and Tasks
Shared-memory data takes the form of variables as per IEC 61131-3, which
are declared as global variables during configuration in the MULTIPROG
programming system. They are accessible to the OPC server by default and,
for example, they are used by the Schleicher Dialog operating tool.
In the multi-tasking operating system, PLC task 6 is synchronised with the
interpolation task of the CNC controller. The cycle time of task 6 is then
oriented on the interpolation cycle of the CNC.
10.3
Access to the Shared memory
The data structure of the shared memory is created during installation of the
PLC or CNC operating system. For pure PLC, only the variable areas for
PLC specification and errors are created (
plcSect
and
errSect
, see below).
The PLC program has access to the entire shared memory via the global
variable
plcMem
(for PLC controllers) or
cncMem
(for CNC controllers).
The individual components of the shared memory can be accessed by using
dot notation. For example, the PLC program can read the version number of
the controller operating software as follows:
cncMem.plcSect.lOSVersion.
Visualisation systems have access to the shared memory via the OPC
interface. For example, the version number of the operating software can be
read from the OPC variables
cmpS_lOSVersion
.
The individual components for read and write access (e.g. version numbers,
error messages, bit signals, word ranges, NC data, CAN data, etc.) are
combined in sections. The retentive variables (retain) occupy their own
sections.
