Provided is a method for stabilizing and increasing the speed of processing for writing a plurality of different-sized files such as a video file and a management file in parallel in the case where the area in a non-volatile memory of an information recording module is managed by a file system. An access module (1) includes a means for retaining sequential areas in logical block units as areas for writing file data, and a means for realizing file data addition and overwriting by writing data to logical blocks and changing links in a FAT regardless of whether file data addition or overwriting is performed. Writing to the information recording module is performed by writing to sequential addresses in the logical blocks. This realizes the stabilization of and an increase in the file data recording speed by suppressing needless copy processing performed in the information recording module 2 in the case of recording a plurality of files such as a video file and a management file in parallel.