Evaluation Environment for AUTOSAR-Autocode in Motor Control ...

SWC1 SWC2 SWC3
2.6 Configuration Files
. . .
Figure 2.7: VFB diagram
SWCn
Virtual Functional Bus
2.6 Configuration Files
To do the mapping to the ECUs, which is described in section 2.2, it is necessary to
know a lot of information about every part of the AUTOSAR system. This means
the precise description of a SWC for each mechanism described in section 2.4 and
the configuration of the ECUs and the system. This configuration is done in an
XML format for a defined XML scheme. The concrete XML scheme depends on the
AUTOSAR release. For one release some different scheme versions can exist, as a
result of bug fixes and updates.
AUTOSAR distinguishes two cases of specifications. The specification of a SWC
together with its internal behavior is called a SWC description. Everything that goes
beyond the scope of a single component is called a configuration. Together with a
SWC description it is possible to deliver the component to suppliers.
AUTOSAR does not specify, which information has to be put in which files. Instead
the structure of the files is flexible that the whole configuration can be put in one file
or every object can have its own file. To reference an object in an XML file a unique
path is used, which consists of the package names that have to traversed in the XML
tree to reach this object. An example is given in section 2.8.
2.7 Runtime Environment
The RTE is the implementation of the VFB for one specific ECU. It provides the
environment which is needed for the SWCs to run on that ECU and communicate with
other SWCs. The RTE encapsulates the communication between the components, so
that they don’t know were the counterpart of the communication is located. This
means, that the communication with a component on the same ECU is done directly,
whereas the communication with a component, which is located elsewhere, is done
through a communication mechanism like CAN or LIN. But the RTE does more than
just provide the connections of the VFB. It additionally ensures that runnables of a
SWC are triggered through the configured events, provides consistency for IRVs and
ensures the effect of exclusive areas. Or in short, it provides the functions for all the
configured mechanisms.
As earlier described the RTE is auto generated from the RTE generator but this is
15