Abstract: A digital audio tape recorder is used as a digital data storage recorder and digital signals containing main data and sub-data are recorded in separate areas in each track of a plurality of tracks formed on a recording medium, wherein a predetermined number of tracks constitute a group and a plurality of groups are recorded on the medium. In the sub-area an identification signal is further recorded which indicates whether or not main data recorded in the main areas of a given group is same as the main data recorded in the main areas of preceding and subsequent adjacent groups. When identical data is multiply written for a plurality of units, a division of the multiply written portions is detected, and signal processing is facilitated.

Abstract: In this invention, a predetermined amount of data is given as one frame, and data having a predetermined format is recorded for each frame. A first area recording main data and a second area recording sub data are formed in each frame. Plural types of units each consisting of a plurality of frames are set, and a number of first units from a leading end of a recording medium and the numbers of other units from the leading end of the recording medium to a trailing end of the first units are recorded in the second area of a frame constituting the unit including the trailing end, thus facilitating a high-speed search operation.

Abstract: A method of position detection on a recording medium is performed by moving the recording medium alternately in normal and reverse directions, while searching for a target position, and decreasing the travel speed of the recording medium with each change in direction. Immediately after a target position has been finally passed, a report signal of the search completion is generated, thereby shortening the search time.