Hierarchical BIT: reusable BIT software for integrated systems

The authors present a hierarchical BIT (built-in test) implementation for integrated advanced avionics systems to support multiple levels of integration and test. This hierarchical design allows BIT to be reused in several test environments, including module, subsystem, and system test. The authors examine some of the costs, benefits, and tradeoffs made in developing a hierarchical BIT. The hierarchical BIT requirements are discussed. Hardware portability must be addressed by the use of high order languages and a modular design. Varying platforms and test environments must be accommodated by flexible tests which utilize test parameters and generate appropriate results. System reconfigurability must be considered by designing nondeterministic tests which can be executed with limited resources, and the design and configuration management processes should be modified to support the BIT design