According to one aspect of the present invention, the flash memory comprises a memory region divided into a plurality of real banks, wherein from among the plurality of products which consists of a plurality of combinations of virtual banks having at least one real bank; and a combination of the top boot in which the most significant address is allocated to the boot bank having the boot sector and the bottom boot in which the least significant address is allocated to the boot bank, product information data are set in a product information record section, whereby any product can be configured.