Patent ID: 6366977
Filing Date: 2002-04-02
Classification: G06F

Abstract:
A semiconductor storage device that uses nonvolatile memory and is used in a host system device such as an information processing device, said semiconductor storage device comprising:an interface for interfacing with the host system device; a memory unit comprising a plurality of nonvolatile memory areas that enable data transfer in a unit cluster; a buffer unit comprising volatile memory used as cache memory for data transfer between the host system device and the memory unit via the interface; and a controller for controlling the memory unit and the buffer unit according to commands from the host system device, wherein the controller accesses and uses the buffer unit using a sector address format corresponding to one cluster of the memory unit, wherein when particular data is read from the memory unit, a cluster of the memory unit to which the particular data is stored is read into the buffer unit, and the particular data is then read from the buffer unit for transfer to the host system device, a capacity of the buffer unit is equivalent to one cluster of the memory unit, and the buffer unit has the sector address format assigned thereto corresponding to one cluster of the memory unit, and the data at a particular sector address designated by the host system device are read from the buffer unit.