Abstract: The present invention relates to a PC card detachably installed and used for an information processing device such as a personal computer, digital-still-camera and so on to process a variety of information and its objects is to provide a PC card connectable to a plurality of information processing devices without losing the advantages of easy detachability, flexibility and portability originally owned by the PC card. A structure is formed to provide a first interface section 100 to execute data transfer between a function block supplying a predetermined function for information processing device and a portable PC (omitted in FIG. 1), and a second interface section 101 having a different interface specification from the first interface section to transfer data between the function block 2 and a desktop PC 10.

Abstract: A flash memories (20, 21) are coupled with a host computer (1) through a flash memory controller (2) which has a pair of data buses (27, 28), and a pair of buffer memories (22, 23). Each of said data buses is coupled with a related flash memory, and a related buffer memory, which is coupled with said host computer. Said data buses (22, 23) are controlled to operate simultaneously so that said flash memories are accessed simultaneously in parallel form. A data in said host computer is transferred to said flash memories through said buffer memories and said data buses, and vice versa. All the elements (20, 21, 2) are mounted on a plastics card (100) called a flash memory card, which is coupled with a host computer through a connector. Because of use of a plurality of buses operating in parallel form, the transfer time of data between a host computer and a flash memory card is shortened.