Recursive pseudoexhaustive test pattern generation

A recursive technique for generating exhaustive patterns is presented. The method is optimal, i.e., in one experiment it covers exhaustively every block of k adjacent inputs in the first 2^k vectors. Implementation methods based on characteristic functions of test vectors are provided. They include a parallel pattern generator employing an exclusive-or array, and two serial generators that can be easily adopted in a scan-based built-in self-test environment