Reliability of data that is stored in a disk drive by a storage system is enhanced. An information apparatus has a processor, a memory, an interface control unit, and a system control unit, which controls communications between the processor, the memory, and the interface control unit. The system control unit judges whether to attach, to data that is transferred between the memory and the system control unit, an error detecting code for protecting the data based on an address in the memory at which the data to be transferred is read or written.