The invention provides a double 2-vote-2 redundant
system and method. The
system comprises a first part, a second part and a switching mechanism, wherein the first part comprises a first subsystem, a second subsystem and a first gate circuit, the first subsystem and the second subsystem are connected through a first main
serial communication circuit and a first auxiliary
serial communication circuit, the second part comprises a third subsystem, a fourth subsystem and a second gate circuit, and the third subsystem and the fourth subsystem are connected through a second main
serial communication circuit and a second auxiliary serial communication circuit; all the subsystems receive the same input
signal at the same time and conduct the same
processing, each subsystem receives opposite-end
data information from the corresponding subsystem at the opposite end through the corresponding main serial communication circuit and auxiliary serial communication circuit, sends local-end
data information to the subsystem at the opposite end, and compares the opposite-end
data information with the local-end data information and generates a comparison result
signal, each gate circuit generates
processing result signals according to the comparison result signals generated by the subsystems, and the switching mechanism generates switching control signals according to the
processing result signals generated by the gate circuits. According to the double 2-vote-2 redundant
system and method, more advanced double 2-vote-2 redundant system design is realized.