Abstract: The present invention provides a control method for an error detection & correction apparatus, comprising a plurality of data processing apparatuses which reside in a data communications path and partake in exchanging data by the unit of error correcting code, and a plurality of information exchange paths which are installed between the plurality of data processing apparatuses; and generating a true syndrome by exchanging a partial syndrome relating to a part of the data partaken by each of the data processing apparatuses by way of the information exchange paths, comprising the step of exchanging renewal information relating to a part of the data partaken by each of the data processing apparatuses with the other data processing apparatus by way of the information exchange path.

Abstract: Two data communication paths (first and second data communication paths) are provided between first and second data processor devices. First and second I/O ports are provided between the first data processor device and the first data communication path. Third and fourth I/O ports are provided between the second data processor device and the second data communication path. When failure occurs in the first data communication path, the data transmitted from the first data processor device is transferred to the second data processor device through the first I/O port, a bypass communication path, the second I/O port, the second data communication path, the third I/O port, a bypass communication path, and the fourth I/O port.