ILLINOIS UNIV AT URBANA-CHAMPAIGN COORDINATED SCIENCE LAB
One of the objectives of this work is to study the design of totally self-checking systems that are made up of blocks whose fault behavior is different from one another. Consequently, different codes are mentioned and their associated circuit structures discussed in detail. Codes that are used to protect against unidirectional errors are studied. Systematic and non-systematic codes are shown to have the same basic structure. The structure of non-systematic unordered codes, more precisely the class of fixed-weight codes, if further examined. It is shown that these codes have codewords that can be effectively classified in terms of congruence, cycling and complementation classes. The capabilities of unordered codes are defined with respect to circuit structure and fault models. Some results, based on the previous classification scheme, are presented on the design of two-level minimal checkers.