SoC and Board Modeling for Processor-Centric Board Testing

Many contemporary electronic systems are based on System-on-Chips (SoC) such as micro-controllers or signal processors that communicate with many peripheral devices on the system board and beyond. While, SoC test was a topic of extremely high interest during the last decade, the test beyond SoCs didn't get much attention after introduction of Boundary Scan (BS) 30 years ago. It is not a surprise that the restricted capabilities of BS with respect of such modern challenges as dynamic (timing-accurate), at-speed and high-speed testing as well as in-system programming create considerable troubles for test engineers in production environments. In this paper, we point out particular challenges in testing the system's infrastructure beyond the SoCs as well as propose a general modeling methodology for test automation for microprocessor SoC-based system boards. The new so-called "Lego-style" test automation methodology forms a complimentary solution to traditional boundary scan. Together, they provide extended fault coverage that targets shorts, opens, stuck-at faults as well as dynamic faults (e.g. delays and transition faults). The "Legostyle" model allows reducing the labour effort drastically once the library of model components is created.