A method and system is provided for a nuclear reactor safety related
application. The method includes executing two forms of a same
application-specific logic, one of the two forms implemented as hardware
logic, and the other of the two forms implemented as software
instructions for execution by microprocessor-based controlling software.
Each form of the application-specific logic is executed with a same set
of inputs. The method compares a result produced from the execution of
the hardware-implemented form to a result produced from the execution of
the software-implemented form. When the compared results concur, the
controlling software performs actions associated with the concurring
results by executing microprocessor-based software. When the compared
results fail to concur, the controlling software reports the failure of
the compared results to concur to an operator by executing
microprocessor-based software, and thereafter places the
microprocessor-based software system into an inoperative (INOP) mode.