The Direct Summation of Totally Self-Checking Checkers

A new technique for reducing the complexity of designing Totally Self-Checking (TSC) checkers for m-out-of-n codes is presented. The method is based on the partitioning of the input variables into r classes, then partitioning the code groups generated into Z output partitions. Comparison with earlier results reveals improvements in design simplicity and logic and testing complexity. This thesis also presents a new method of TSC checker design where a j-level m1/n1 code and a k-level m2/n2 code TSC checker are directly summed to form a max [j,k]-level (m1 + m2) / (n1 + n2) TSC checker. A library of m/n code TSC checkers can then be used as building blocks for other m/n code TSC checkers