A terminal that performs secure boot processing when booting, thereby booting reliably even if, during updating of a software module, the power is cut off or the update is otherwise interrupted. A linear compressor is supported for operation within the housing. The relay link setup request frame and the relay link setup response frame may pass through the relay station. Later, the stored magnetic-polarity transitions are read from the disk surface and the randomized user bits and ECC bits, including any inverted bits, are recovered.