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The requirement for an automated test system has immensely increased due to the realization that manual testing is associated with additional resources and staffing constraints. In order to achieve a competitive edge, reduced development cost, timely product delivery, and product quality are mandatory in today's organization. Manual testing requires skilled operators that increase cost, time, and product delivery. The low cost computer-based automated system helps to get an edge by fulfilling these organizational demands. In this paper, an automated testing system has been developed to support functional testing of all phases of Nortel Networks 1-Meg modem system as its system under test (SUT). The modem is an inherently complex asymmetric digital subscriber line (ADSL) product and its testing is far more complex than just verification of process faults. The complexity of ADSL system renders automated test system an important and imperative part of ADSL testing. The subject paper demonstrates the indispensable need of automated test system for ADSL testing and its relative advantages in providing some benefit for the organization.

The implementation of fault testing environment for embedded cores-based digital circuits is a challenging endeavor. The subject paper aims developing techniques in design verification and test architecture utilizing well-known concepts of hardware and software co-design. There are available methods to ensure correct functionality, in both hardware and software, for embedded cores-based systems but one of the most used and acceptable approaches to realize this is through the use of design-for-testability (DFT). Specifically, applications of built-in self-test (BIST) methodology in testing embedded cores are considered in the paper, with specific implementations being targeted towards the International Symposium on Circuits and Systems (ISCAS) 85 combinational benchmark circuits.

The design of aliasing-free space support hardware for built-in self-testing in very large scale integration circuits and systems is of immense significance, specifically due to the design paradigm shift in recent years from system-on-board to system-on-chip. This paper discusses approach to realizing aliasing-free space compaction hardware targeting particularly embedded cores-based system-on-chips for single stuck-line faults, extending well-known concept from conventional switching theory, viz. that of compatibility relation as used in the minimization of incompletely specified sequential machines. For a pair of response outputs of the circuit under test, the method introduces the notion of fault detection compatibility and conditional fault detection compatibility (conditional upon some other response output pair being simultaneously fault detection compatible) with respect to two-input AND/NAND, OR/NOR and XOR/XNOR logic, respectively. The process is illustrated with design details of space compactors for the International Symposium on Circuits and Systems or ISCAS 85 combinational (and ISCAS 89 full-scan sequential) benchmark circuits using simulation programs ATALANTA and FSIM, attesting to the relevance of the technique from the viewpoint of simplicity, resultant low area overhead and full fault coverage for single stuck-line faults, thereby making it an appropriate choice in commercial design environments.

The design of space-efficient support hardware for built-in self-testing (BIST) is of immense significance in the synthesis of present day very large-scale integration (VLSI) circuits and systems, particularly in the context of design paradigm shift from system-on-board to system-on-chip (SOC). This paper presents an overview of the general problem of designing zero-aliasing or aliasing-free space compression hardware in relation to embedded cores-based SOC for single stuck-line faults in particular, extending the well-known concepts of conventional switching theory, and of incompatibility relation to generate maximal compatibility classes (MCCs) utilizing graph theory concepts, based on optimal generalized sequence mergeability, as developed by the authors in earlier works. The paper briefly presents the mathematical basis of selection criteria for merger of an optimal number of outputs of the module under test (MUT) for realizing maximum compaction ratio in the design, along with extensive simulation results on International Symposium on Circuits and Systems or ISCAS 85 combinational and ISCAS 89 full-scan sequential benchmark circuits, with simulation programs ATALANTA, FSIM, and COMPACTEST.