SAE AS5506/1

Abstract

This document contains three annexes to the SAE AS5506 Standard The SAE Architecture Analysis and Description Language.<br>The first annex, Annex A Graphical AADL Notation, defines a set of graphical symbols for the graphical AADL notation. These graphical symbols can be used to express relationships between components, features, and connections in an AADL model. Graphical AADL diagrams are legal in accordance with the AADL core standard if the AADL model being presented graphically is legal and if the correct graphical symbols are used. For example, a graphical editor is not permitted to create a connection whose source and destination are not connected. Graphical presentations of AADL models are permitted to show subsets of legal AADL models. For example, property values may be entered through a property sheet or dialog box. The figures in this annex present different views of an AADL model. These views are not prescriptive, but intended to illustrate possible views and layouts.<br>The second annex, Annex C AADL Meta Model and Interchange Formats, defines the AADL meta model and XML-based interchange formats for AADL models. The AADL meta model defines the structure of AADL models, i.e., an object representation of AADL specifications that corresponds to a semantically decorated abstract syntax tree. The object representation of AADL models can be manipulated programmatically through an API. The object representation of AADL models can also be persistently stored as XML documents in a standard interchange format. This permits different tools that support the AADL XML schema [XML 2001] or XMI meta model specification [XMI 2003] to interoperate on AADL models. Both the XML schema and the XMI meta model specification for the AADL are derived from the AADL meta model, thus, the two representations are consistent with the meta model.<br>The third annex, Annex D Language Compliance and Application Program Interface, defines language-specific rules for source text to be compliant with an architecture specification written in AADL. While the AADL is source text language independent, this annex provides guidelines for users to transition between AADL models and source text written in Ada [ISO 1995, IEEE 2001] and source text written in C [ISO 1999]. This annex recommends the use of an Application Program Interface (API) between the application software and the execution environment to facilitate the use of mixed language application source code modules in a common execution environment.<br>The forth annex, Annex E Error Model Annex, defines features to enable the specification of redundancy management and risk mitigation methods in an architecture, and enable qualitative and quantitative assessments of system properties such as safety, reliability, integrity, availability, and maintainability. This annex defines a sublanguage that can be used to declare error models within an error annex library and associate them with components in an architecture specification. This annex also defines a sublanguage that may be used within an error annex clause within a core AADL standard implementation declaration.<br>Purpose<br>The purpose of this document is to supply the information needed to integrate the SAE AADL notation with tools that enable the production of high quality, safety-critical, real-time, embedded systems from AADL specifications. The material contained in this standard may be used to facilitate the development of graphical tools that may be used to generate graphical representations of AADL specifications. This document also includes the specification of the models needed to allow the contents of AADL specifications to be transformed into representations that are interchangeable with other tools. Finally, this document contains guidelines that supplement the transition between AADL models and software source code.