| Today the usual proceeding for realising a specific
configuration for a control system is of a static nature. Before run-time the software is
completely compiled and linked and forms one executable which is downloaded to the
control. This solution is however inflexible and requires high efforts if modifications
and additions are necessary after the delivery of the control. To
overcome this situation a fully modular system is needed where the actual topology of the
software is generated at the boot-up of the system. For this, the system platform has to
contain a configuration system which is able to handle a library of AO classes. At boot-up
AO's of the different classes are instantiated and communication connections between AO's
are established.
The actual topology of the control system is described in an
externally generated ASCII configuration list which is interpreted by the configuration
runtime system (CRS). A graphical configuration editor can be used to define the
configuration order in a manner like CAD-systems are used to define the layout of a
processor-board.
The configuration order contains a list of all AO instances that are
necessary for a specific control system satisfying the requirements of a control
application. It is possible that there are several instances of the same AO class, e.g.
class Axis Control. For every AO the client/server relationships are defined. Every
relationship between a client and a server AO consists of a list of communication objects
of the server which will be used under specific names in the client.
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