Abstract: A data recording method and apparatus with reduced probability of error occurrence in main data. For recording data on azimuth tracks on a magnetic tape by a rotary magnetic head, each azimuth track is divided into a main data area and margin areas on both sides of the main data area. The main data recorded in the main data area of each track is arrayed two-dimensionally. An error correction code C2 is appended to a data string arrayed in the track direction, while an error correction code C1 is appended to a data string arrayed along the track width. The error correction code C2 is divided into two portions which are arrayed on both sides of the main data area of each track. This reduces the probability of error occurrence in the main data.

Abstract: A data recorder includes a recording unit for recording data having a predetermined data format and a frame address in a recording medium in units of frames each consisting of predetermined amount of data, and for forming a plurality of Partitions each consisting of a plurality of data areas in which different types of data are recorded during recording. The data recorder performs initialization of a length of at least one of the Partitions.

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: An apparatus and method for recording and/or reproducing digital data employing a DAT (digital audio tape recorder) adapted to record and/or reproduce data from a computer or the like in accordance with the DAT format. Main data is recorded in a main area of a track while error detecting data for the main data recorded in the main area of the track is recorded in a sub-area of the track to thereby easily detect an error in the main data.

Abstract: An apparatus and method for recording and/or reproducing digital data employing a DAT (digitial audio tape recorder) adapted to record and/or reproduce data from a computer or the like in accordance with the DAT format. Main data is recorded in a main area of a track while error detecting data for the main data recorded in the main area of the track is recorded in a sub-area of the track to thereby easily detect an error in the main data.

Abstract: Before reading/writing a newly loaded data tape, it is known to carry out read/write tests on the tape drive concerned by using a section of the tape set aside for this purpose. This test section is generally marked off by formatting keys which must be accessed and read to identify the test section. In order to facilitate access to the test section, the disclosed data storage method locates the test section in the region of tape between a beginning-of-media BOM position and a beginning-of-recording BOR position with the latter being at a known distance from BOM. As a result, it is possible to rely simply on displacement measurement to access the test section from BOM. As a precaution, a check can be made for possible overshoot error in the tape positioning means so as to avoid testing being carried out beyond BOR.

Abstract: Digital data is formatted and recorded in track pairs on a tape by the rotary heads of a DAT so as to have a header portion for each track which includes a frame number, error correcting code, ID and so on added to the digital data, the content of each header portion of the tracks for any given frame being equal whereby it is possible to easily detect, upon reproduction, unerased data signals due to head clogging and so on by comparing portions of the two header portions of each frame and error correcting the data from those tracks where it is determined that the compared header portions contain different data.

Abstract: An apparatus for recording and/or reproducing digital data information on a recording medium which has a recorder similar to a digital audio recorder (DAT) which records digital signals in a frame made up of two oblique tracks formed by rotary heads and a controller for dividing the digital data information at a predetermined frame portion and supplying the divided information to the recorder as a digital signal, wherein since the digital data information are divided at the predetermined frame portion, they are easily re-recorded.

Abstract: In an apparatus for reproducing a digital signal wherein a signal is read by a plurality of reproducing rotary heads which trace a track with an interval narrower than the interval of tracks formed on a tape, a wrap angle with which a tape is wrapped around the periphery of a rotary drum to which the rotary heads are attached is selected to be less than 360.degree./n with respect to the number n (n is an integer) of rotary heads, the rotary heads are rotated at a speed twice the normal rotational speed of the heads, the demodulated digital signal is stored in a memory corresponding to a frame address and a block address detected from the reproduced digital signal, and then the digital signal stored in the memory is read out therefrom in a predetermined order, whereby an apparatus for correcting the tracking of the tape by the rotary heads can be eliminated.

Abstract: A data streamer using a digital audio tape recorder (DAT) arranged such that even when the supply of incoming data to be recorded is interrupted, the data recorder is operated continuously and a data invalid signal is recorded on the tape in an area other than the data recording area, whereby the data recorder can record data at a high recording rate and in short time.

Abstract: In an error correction method using Reed-Solomon code when the error correction is performed by using the result of the multiplication of a syndrome and an error location, another syndrome is added to thereby form a new syndrome. By repetitively executing this procedure, the error vector is obtained by a small number of arithmetic operations relative to a known procedure, thereby performing error correction by the so-called erasure correction technique. Then, by calculating another error vector using the first calculated error vector, the number of arithmetic operation times can be even further reduced.

Abstract: The present invention is concerned with a method and apparatus for detecting control signals recorded on a continuous recording area on the recording medium at an elevated speed. When k out of n past read-out control signals have been read correctly as being the prescribed control signal, the signal is concluded to be the prescribed control signal. It is possible in this manner to read out the control signals accurately even when the error rate is high, as during high speed searching.

Abstract: A rotary head type digital tape recorder in which a PCM signal and sub data for control and the like concerned with the PCM signal are recorded and/or reproduced by rotary heads. The invention relates to a method and apparatus for transmitting and/or receiving a digital signal in such a type of digital tape recorder by using a data format such that when the serial data is input and output each of a predetermined number of words of the reproduced PCM signal and each symbol of the reproduced sub data are transmitted as a pair synchronously with the rotation of the rotary heads. Thus, a large amount of sub data can be input and output together with the PCM signal.

Abstract: A decoding apparatus in which the operation to write error correction coded data into a memory and a decoding processing operation of the data read out of the memory are executed in parallel. This decoding apparatus comprises: a comparator for comparing the address to write the data into the memory with the address in the memory for the decoding processing operation; and control means for inhibiting the writing operation when it is detected by the comparator that the decoding processing operation is precedent to the writing operation. With this apparatus, the data which was subjected to the correcting process is prevented from being rewritten into the memory and the pointer derived by the decoding process from being broken.

Abstract: The invention relates to a digital signal reproducing apparatus to which continuous blocks of input data are supplied, each block consisting of a PCM signal which was error correction coded and additional codes which were subjected to error detection or error correction coding processes. The error pointers are set independently of the result of the error correction of the PCM signal on the basis of the decoding state of the decoder for decoding the additional codes using the error detection code or error correction code.

Abstract: In a method for decoding an error correction code in which a first correction code of (n.sub.1, k.sub.1) (where n.sub.1 denotes the code length) is encoded for every k.sub.1 information symbols arranged in each column and a second error correction code of (n.sub.2, k.sub.2) (where n.sub.2 denotes the code length) are encoded for every k.sub.2 information symbols arranged in each row of a two dimensional arrangement of (k.sub.1 .times.k.sub.2), a first pointer formed by decoding the first error correction code is stored in a memory having n.sub.2 bits, a second pointer formed by decoding the second error correction code is stored in a memory having k.sub.2 bits, reliability of the information symbols is evaluated on the basis of status of the first and second pointers when the information symbols is outputted.

Abstract: This invention relate to a synchronizing circuit for a data signal in which a data signal is divided at every predetermined number of bits, and every divided data signal is added with a synchronizing signal, an arbitrary address signal and an error detection signal for the address signal and received so as to be written in a memory in accordance with the address signal, which includes means (4) for detecting the synchronizing signal and means (3) for detecting an error of the address signal.

Abstract: An apparatus for recording and/or reproducing digital information signal with sampling frequencies fs1, fs2, fs3, --- fsn comprising circuit for selecting one of the sampling frequency, and circuit for generating a field clock having a field frequency F determined by a following equation;fs1/N1=fs2/N2=fs3/N3=--- =fsn/Nn=Fwherein N1, N2, N3, ---Nn are the number of data words in one field.

Abstract: An encoding method for error correction of digital information data is provided. The encoding method comprises the steps of arranging the digital information data in a plurality of blocks each including a plurality of symbols, and generating first redundacy data from first respective groups of digital information data constituting symbols which exist in at least two blocks in a first direction. Second redundancy data is generated from second respective groups of digital information data constituting symbols which are included in the plurality of blocks in a second direction. First code sequences are formed for first error detection from the first digital information data groups and the first redundancy data, and second code sequences are formed for second error detection from the second digital information data group and the second redundancy code.