ModelBased Embedded RealTime Software Development

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Model-Based Embedded Real-Time Software
Development

• Dionisio de Niz and Raj Rajkumar
• Real-Time and Multimedia Sys Lab
• Carnegie Mellon University

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Para-Functionals
Para-functional
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Embedded Systems Composition
Software

Embedded System
Hardware
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Embedded Software Different Para-Functional
Properties
Software

radar scan
track
Embedded System
Hardware
Reliability
Throughput (trajectories / s)
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Embedded SoftwareHeterogeneous Platforms
pthread_create()
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DRE Model Requirements

• Composability
• Encode para-functionals
• Compose them into final system
• Correctness
• Reflect consequences of design choices
• Prevent incorrect choices
• Fidelity
• Reflect implementation deployment
• Enable Reuse

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Time Weaver

• DARPA MoBIES funded project
• Component-Based Modeling Framework Tool
• Build run time through models
• Timing model
• Encode component relationships in couplers
• Decompose relationships of different aspects into
  different dimensions
• Enable recursive composition in functional and
  para-functional aspects
• Enable reuse of functional and para-functional
  constructs

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Inter-component relationships decomposition
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CouplerInter-component relationships
decomposition
Coupler manipulate port elements to construct
relationship
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Basic Mechanisms of Couplers

• Property Propagation
• Relate properties of associated components, e.g.
  period
• Constraints
• E.g. both component not on same processor
• Synchronization
• Arbitrarily complex synchronization protocol
  among group of ports (e.g. mutex, virtual
  synchrony, barrier)
• Inter-component communication
• Mechanism used, e.g. invocation, CORBA, multicast
• Specified at highest level (when network defined)
• Automatic discovery and change of components
  affected

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Independent Dimensions
Semantic Separation Projections to other
dimensions
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Inter-dimensional projections
Deployment
Processor
Processor
Network
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Modeling Dimensions in Time Weaver

• Functional
• Functional relationships
• Deployment
• Hardware description binding
• Timing
• Timing relationships (periods, deadlines)
• Fault-Tolerance
• Replication
• Concurrency
• Threading, synchronization
• Modality
• Modes mode switching

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Ongoing CollaborationsDARPA MoBIES

• Avionics OEP Boeing, LM
• Software Radio SwRI
• Automotive OEP Berkeley, Ford GM

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Avionics OEP
Time Weaver
Rational Rose UML
?
?
XML
?
?
Target

?
TimeWiz
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Avionics OEP

• Interface with multiple tools
• Standard XML interfaces
• IIF, AIF, ACL, Configurator
• Large model for scalability testing

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Software Radio OEP
Matlab
Time Weaver (DSP Processing)
TimeWiz
Linux
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Software Radio OEP

• Unifying modeling of simulation and final
  run-time
• Generate matlab code for simulation
• Generate C code for final runtime (on Linux)

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Automotive OEP
TimeWiz
Time Weaver
uCOS-II / ARM
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Automotive OEP

• Take the simulation model to final running code
• Small footprint of network of processors
• uCOS-II / ARM7

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Summary

• Model of para-functional properties of DREs
• New Abstraction coupler
• Separation of para-functional properties in
  independent dimensions
• Ongoing experiments with Avionics, Automotive and
  Software Radio OEPs