LAOS – A Real-time Operating System by Liebherr-Aerospace
Liebherr-Aerospace Operating System (LAOS) is a time- and space-partitioned real time executive tool, designed to meet the requirements that Liebherr-Aerospace established for its electronic control units. The designation is to schedule the resources of standard microcontrollers systems and provide the services necessary for the optimized use of the electronic capabilities for Liebherr-Aerospace’s system applications.
In general, LAOS implements features and services necessary to control a microprocessor board on the basic concepts of the ARINC653 standard. The fully defined driver layer assists and supports a rapid portability to new controller architectures.
The means for direct integration to MATLAB Simulink, for model based application development are provided.
The next development steps are now adaptions of LAOS to be usable with SCADE models.
The system is principally portable to every standard microcontroller board and is, to date, available on the following microcontrollers:
- NXP MPC5674F
- NXP MPC5777C
- NXP MPC5746
- TMS570
- Vybrid M4
- Infineon TC29
LAOS provides standard Real Time Operating System services, space and time partitioning, data loading, failure storage and is supplied with a configuration tool, supporting the hardware and project specific setups and adaption of the electronic system.
High and low level software requirements are available for the system, the corresponding test cases and procedures are in work. For qualification/certification purposes, these design- and verification artefacts are ready to use (only project specific adaptions are necessary) within the frame of the project software qualification/certification.
Note:
The reason to develop your “own” Real Time Operating System is certification. A product, that you have designed from the beginning by yourself for aerospace application demands “certification ability” (DO-178) only.
You know the required content and your expectations and can adapt the content to your needs.
LAOS memory footprint (TC299)
LAOS module | Description | Memory demand for an example project |
---|---|---|
Board Configuration | Complete LAOS board configuration | 143KB |
Corre | Core functions, Firmware TC299 and Extensions | 32KB |
Driver Section | Complete hw drivers | 15KB |
Loader | ARINC615; Ethernet, CAN, ARINC429 | 76KB |
Application | Example Project | 226KB |
Key timing margins (TC299)
Description | Duration | |
---|---|---|
GetTime | Get current time using ApexGetTime function. | 0.93 US |
GetTimeUS | Get current time in µs using LapexGetTimeUs function. | 0.83 US |
Context Switch | Time used for start and end partition. The schedule overhead. | 3.66 US |