In that event, one of the Data Registers 81 a is used to supply 512 bytes of data to the host device 20 with data previously loaded from one page of the NAND memory 14, while the other Data Register 81 b is used to load data from another page of the NAND memory 14 into the Data Register 81 b, to supply the data to the host device 20 after the data from the Date Registers 81 a have been completely