Software-Based Self-Test for Reliable Applications in Railway Systems

The introduction of computers in the control and automation of railway systems led to the massive use of microprocessor-based devices in almost all critical elements of a modern railway infrastructure (e.g., signaling systems, trains control, etc.). Therefore, microprocessor-based systems play a crucial role in the safety, reliability and security of these infrastructures. The very strict safety standards, which must be guaranteed in a railway system, make the testing of all electronic components a unique and challenging case study. Software-based self-test represents a very attractive test solution to cope with the problem of on-line and off-line testing of microprocessor-based systems. It makes it possible to deeply test hardware components without introducing extra hardware and stressing the system in its operational condition. This chapter overviews the basic principles of software-based self-test techniques, focusing on a set of best practices to be applied in writing, verifying and computing the final test coverage of high-quality test programs for railway systems.