An information recording device includes a control unit and a memory
interface unit. An ICV for each sector data of data to be stored in units
of sectors is stored in the redundant part of each sector. An ECC and an
ICV are stored in the redundant part of each sector, so that sector-unit
ICV storage can be performed without reducing the storage capacity of the
data part of the sector. processing that combines data parts by using the
file system of a device can be performed similarly to conventional data
combination processing that only combines data parts in which ones purely
used as data are stored. The control unit does not have any load because
only each sector which is regarded as valid (no interpolation) as a
result of ICV checking is transmitted to the control unit, and the ICV
checking is performed by the memory interface unit.