The present invention relates to methods and compositions that control, i. The byte code includes an 8-byte-unit copy instruction and direct data processing instruction, and the compression apparatus determines whether to use the 8-byte-unit copy instruction and direct data processing instruction or a byte-unit copy instruction and direct data processing instruction upon decompression, and generates the byte code. Further, because the magnetic pole is provided on a position which is offset in one direction from the center of the magnetic body, there will be no interference between the magnetic head and the cartridge or mechanical components even when the size of the core is increased due to the core of the raised shape.