Taming Interrupts: Deterministic Asynchronicity in an ARINC 653 Environment
Overview
Interrupts are forbidden in ARINC 653 partitioned environments – or so it appears. In this paper we will examine that prohibition and explore a means of using interrupts in a system while maintaining deterministic behavior.
We begin with an overview of the benefits and costs of Integrated Modular Avionics (IMA), along with a review of associated standards. Next, we look at interrupt-driven Input/Output (I/O) handling, which is considered best practice, except in ARINC 653 systems. Because DO-248 requires deterministic behavior as a fundamental system property necessary to certify safety, most IMA system designers avoid interrupts, presuming that such asynchronous events introduce non-determinism and cause interpartition interference.
We conclude with a description of our initial implementation of this innovation within a customized version of the Xen hypervisor.
Topics covered in this paper
- Standards
- Certification
- Aerospace electronics
- ARINC 653 environment software development
- And more…