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In this paper, an executable system model for performing a functional simulation while observing the dynamic effects of mixed-criticality requirements regarding applications with different levels of assurance is proposed. The model provides the expression of dynamic execution modes and execution time estimates on each criticality level of the system. In a refinement step, it is possible to observe the effects of scheduling policies, dynamic criticality-, and execution mode switches on the functional behaviour of the system in a trace-based, simulative manner. An early evaluation of a quadrocopter platform consisting of a safetycritical flight control application and a video-based, performancecritical object detection is used to demonstrate the applicability of the design flow. Simulation results indicate that by defining multiple execution modes of the object detection algorithm, the run-time utilisation feedback allows the algorithm to run in a high-quality mode for more than 50% of the time, thereby increasing the overall system utilisation by two thirds compared to a static resource utilisation analysis.

Implementation of communication between different tasks of a concurrent embedded system is a challenging problem. The aim of our work is to support the refinement and relocation of tasks onto different execution units, such as processors running different operating system or even dedicated hardware. For this purpose communication should be transparent and as independent as possible from the underlying middleware or embedded operating system. Moreover, communication should also be transparent accros the HW/SW boundary.In this work we present a generic framework for seamless communication of (software) tasks with shared resources, called Shared Objects. Communication is implemented using a method-based interface realizing a Remote Method Invocation (RMI) protocol. Our shared communication resources can either be implemented as dedicated hardware, as shared memory or local tasks. The presented framework is a first step towards the unification of shared resource access based on embedded Linux. The effectiveness of our approach is be evaluated with different task mappings and shared resource access implementation styles.

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