The project investigated and documented microprocessor use in the aircraft industry. It documented assessment criteria for microprocessors and safety concerns for their use. Particular attention was given to design and packaging techniques and the effect of pipelining and caching on processor determinism. As the project progressed the effort was expanded to include system on a chip (SoC) devices.
The research effort of the project was comprised of the following tasks.
- Providing input for FAA policy and guidance development regarding use of microprocessors.
- Providing practical evaluation criteria for industry to use in developing systems that use microprocessors.
- Reviewing current utilization of microprocessors and computational processing components, in general, in the aviation industry.
- Assessing the suitability of RTCA/DO-254 to microprocessor usage, and documenting the areas where RTCA/DO-254 falls short for microprocessors.
- Documenting the potential safety issues that occur when using modern microprocessors in integrated modular avionics systems where multiple partitions use the same processor.
- Documenting approaches for evaluating microprocessors to ensure that the safety issues have been addressed.
- Studying the effect of shared resources on timing.
- Studying visibility and debug support.
- Developing an FAA publishable COTS Microprocessor Selection and Approval Handbook containing guidance for selection and evaluation of microprocessors for various levels of criticality in avionics systems.
- Evaluating and validating the safety net methodology non-deterministic microprocessors and SoCs.