Hardware-based weighted random pattern generation for boundary scan

The authors introduce WARP, a weighted test generation system that includes a canonical circuit for resolving weights to any desired precision. Either cellular automata registers (CARs) or linear feedback shift registers (LFSRs) are used as a source of random patterns, and optionally, it is possible to permute and linearly combine random bits from the source to control inputs to the weighting circuit. The authors analyze pattern coverage and conclude with benchmark results on fault coverage differences between CARs and LFSRs