On interacting finite state machine design with self-checking capability

A technique for designing interacting finite-state machines that will be totally self-checking for any single stuck-at fault is presented. M-out-of-n codes are used for both primary output and state assignments. The next state logic (NSL) for each submachine and the output logic (OL) realized are such that any single stuck-at fault results in either single bit error or unidirectional multibit error at the output. An m-out-of-n checker is added to check the validity of the output lines so that any fault can be detected online by the checker.