Patent ID: 7774187

Claim:
A safety protection instrumentation system for a nuclear reactor constructed by using a digital logic, wherein the digital logic comprises: a plurality of functional units having logic circuitry in which output logic patterns resulting from input logic patterns have been verified in advance of installation of the logic circuitry in the safety protection system; and a functional module formed by combining the plurality of functional units so as to form a logic structure in which the logic structure of the combination of the plurality of functional units is different from the logic structure of each of the plurality of functional units individually, wherein, the functional module includes only functional units having a same logic circuit gate structure as that of a functional unit whose performance has been verified in advance, and software which describes effective programs statements executed by hardware and input pattern groups indicating operation paths, uses branch coverage or toggle coverage for evaluating the ratio of the input logic patterns, and determines whether the output logic patterns corresponding to the input logic patterns coincide with predicted patterns calculated from design specifications to verify that the functional units are correctly connected to each other.