- Allied Standards Avionics Architecture Council
Allied Standards Avionics Architecture Council, or ASAAC, is an effort to define and validate a set of Open Architecture Standards for
AvionicsArchitecture, particularly in the field of Integrated Modular Avionics.
ASAAC is managed by the UK Ministry of Defence, and many major European Avionics companies participate in the
Working group, such as:
GE Aviation Systems(formerly Smiths Aerospace)
* ESG Elektroniksystem- und Logistik-GmbH
The ASAAC project was divided into two phases:
* The first phase was an exploratory phase of the IMA concept.
* The second phase was the elaboration of draft standards. The development was completed in May 2004.
* Next was a demonstration phase, and the publication of a
POSIX-based open-source version of the standard
ASAAC initially published provisional standards under the name of Def Stan:
* Def Stan 00 74 [cite web
title=ASAAC Standards Part I - Proposed Standard on Software
accessdate=2008-07-26] : Proposed Standards for Software
* Def Stan 00 75: Proposed Standards for Communications/Networks
* Def Stan 00 76: Proposed Standards for Common Functional Modules
* Def Stan 00 77: Proposed Standards for Packaging
* Def Stan 00 78: Proposed Standards for Architecture
All standards but "Def Stan 00 74" have been withdrawn in July 2007, the MOD and representatives from the
Working groupconsidering that it was the only standard "bearing any influence".
Proposed Standards for Software (Def Stan 00 74)
"Def Stan 00 74" is defined in the context of
Integrated Modular Avionics. Software components are located on modulescite web
title=Flexibility and Manageability of IMS Projects
University of York
* Configuration and initialization: The configuration is considered as defined in a series of blueprints describing thread and process allocation, virtual communication channels... However, the standard does not define precisely the grammar or the language of these blueprints. As for initialization, there is no specific API to allow initialization by the low-level Real-time operating system (RTOS) services.
* Access to Datas is abstracted from its actual physical storage.
Links to ARINC 653 and POSIX
The field covered by ASAAC in "Def Stan 00 74" is similar to
ARINC 653(ARINC 653 is a software specification for space and time partitioning in avionics). However, there are differences between the two standards: Some features of ASAAC API, such as file handling, thread managing inside process, or debugging, are not considered in ARINC 653.
However, for the part where the two standards overlap, it is often possible to translate ASAAC interfaces in ARINC 653 API calls (and even in
POSIXcalls). Approximately 30% of the ASAAC API is covered directly by ARINC 653 and POSIXcite web
title=An Overview of the ASAAC Standards
For example, the following call defined in ASAAC: receiveBufferwould be translated in ARINC 653 by: RECEIVE_BUFFER()and also in POSIX by: recv()
Links to STANAG 4626
STANAG 4626is a NATOstandardization of the requirements defined by the ASAAC program, proposed by the MOD and the ASAAC Working group.
Integrated Modular Avionics
* [http://www.assconline.co.uk/asaac.asp ASAAC homepage]
* [http://126.96.36.199/documents/BS_Slides-Systems_WG_200705.pdf Presentation of ASAAC Working Group]
* [http://sourceforge.net/projects/asaac-openos/?abmode=1 Open Source OS adaption layer for STANAG 4626]
Wikimedia Foundation. 2010.