Concurrent error detection using monitoring machines

Abstract

In a monitored FSM controller, an auxiliary monitoring machine operates in lockstep with the main FSM, so that any fault in either machine is immediately detected. The monitoring machine provides a uniform mechanism for the detection of stuck-at faults as well as delay faults. The technique yields designs that compare favorably with previous implementations. Not only is fault coverage higher, the hardware cost of the monitored sequential circuit is significantly lower.