Controllability/observability measures for multiple-valued test generation based on D-algorithm

In this paper we propose controllability and observability measures to guide the D-algorithm for multiple-valued logic circuits. The former is determined in one forward traversal of the circuit, and used in determining the line where the consistency operation should proceed. The latter is determined in one backward traversal, and used in executing the D-drive at the fanout point. Our measures are computed by simple recursive formulas, and the time required for computing them is relatively short. The experimental results show that our measures are helpful in reducing the number of times for backtracking.