A succession of input data words is converted into a first succession of information code words including first candidate one and a second succession of information code words including second candidate one different from first candidate one. When a time-ordered data group such as video and music data and the like is recorded into a disk array section to which random access is possible, file controlling information for indicating the link of a plurality of time-ordered data group is produced from the time code of the time-ordered data group. On the other hand, a data path with high power consumption is driven by an external power supply voltage.