JPH041980A - Data recording method - Google Patents

Abstract

PURPOSE:To prevent the damage to a recorded file mark and other data files by providing a spare area after the recording area of each data file and writing the overflowed data in the spare area when an unrewritten data file is rewritten into a new data file of a larger length. CONSTITUTION:When the data are first recorded into a recording medium, an unrecorded spare area SP is provided after a recording area of each data file F(i) every time the file F(i) is recorded. When the file F(i) is rewritten into another data file F(I) of a larger quantity of data, the data overflowed from the unrewritten data file are written into the area SP. Thus the overflowed data are recorded in the area SP right after the recording area of an unrewritten data file even though the quantity of data stored in the new data file F(I) to be rewritten is larger than that of an unrewritten data file F(i). As a result, a new data file can be recorded within an area SP.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a data recording method using a sequential access type data recording and reproducing apparatus using a magnetic tape or a magnetic tape as a recording medium.

Conventional technology In the case of a sequential access type data recording and reproducing device that reads out target recorded data according to the recording order, data recording on a magnetic tape or the like used as the recording medium is as shown in Figure 4. It is done like this.

That is, FIG. 4 is a schematic diagram showing the arrangement of data recorded on the magnetic tape T by the data recording/reproducing apparatus. Each data file F (i-1) F (i), F (
i+1) each represents a collection of related data, and between the recording area of each data file and the recording area of the next data file is a recording area of file mark M indicating the separation of these data files. .

Each data file is composed of a plurality of data blocks, each consisting of a data block (hereinafter referred to as a data block) to which error detection/correction validity is added. For example, for data file F(i), 6
data blocks Did, Di 1. Di2. Di3
．． Di4. Di5, and are recorded on the magnetic tape T in this order.

In this way, in the above-mentioned general recording method, the next data is sequentially recorded immediately after the previous data without providing a spare area in the middle of the recording area, so that the recorded data in the middle of the magnetic tape T For example, even if an attempt is made to rewrite the data file F (i) to another data file with the same amount of data, the rewriting may become impossible.

In other words, rewriting the data file F(i) above is
A part of the recording area of the magnetic tape T when performing door-after-write recording, in which data written by a recording head is read by a reproduction head that follows this head to check whether the data has been written correctly. If there is a defective area with flaws etc., and an error is detected in the data block written to the defective area,
The same data block is rewritten again by jumping over the defective area, and subsequent data blocks are sequentially written. As a result, the amount of data, that is, the file length, of the newly rewritten data file is longer than the file length of the data file F(i) before rewriting by the amount of the defective area, and the file mark corresponding to the data file is The next data file F(i+1) will be overwritten.

Therefore, as a conventional data recording method to eliminate such drawbacks, a method is known in which a spare area SP in which nothing is written is provided in the middle of the recording area of the magnetic tape T, as shown in FIG. There is.

FIG. 5 (1) is a schematic diagram showing the data arrangement on the magnetic tape T before data rewriting, and FIG. 5 (2) is a schematic diagram showing the data arrangement on the magnetic tape T after data rewriting. It is a diagram.

That is, in the magnetic tape T before data rewriting, a spare area SP is provided every five data blocks, and data file F(i) is separated from another data file F(I) as shown in FIG. 5(2). For example, if the recording area to which data block DTI is to be written is a defective area B with a flaw etc., and an error is detected in the recording to the defective area B when read by the playback head, the error The detected data block DII is re-recorded in the subsequent spare area sp.

In this way, in the conventional data recording method described above, a new data file F(l is the next data file F(
i+1) was recorded without overlapping.

Problems to be Solved by the Invention However, in the data recording method shown in FIG. 5 described above, when attempting to rewrite data in a data file,
Rewriting is not possible unless the data amount of the new data file to be written is the same or shorter than the data file before rewriting.

In other words, the data file F(i
) If a data file with a larger amount of data is re-recorded, there is a problem in that the recording area of the data file F(i+1) and file mark M next to the data file (i) to be rewritten will be destroyed.

Therefore, an object of the present invention is to provide data that can be rewritten without destroying other data files, even if the amount of data in the new data file to be rewritten is larger than that of the data file before rewriting. The purpose is to provide a recording method.

Means for Solving the Problems The present invention provides a method for recording data on a recording medium such as a magnetic tape used in a sequential access type data recording/reproducing device that reads out target recorded data according to the recording order. When recording data, for each recording of each data file, which is a collection of related data, a spare area that is not recorded consecutively to the recording area of the data file is provided, and any data recorded on the recording medium is stored. When rewriting a file to another data file with a larger amount of data than this data file, the data that protrudes from the data file before being rewritten is written to a spare area so that the writing of the data file will fit within the spare area. This is a data recording method characterized by the following.

According to the present invention, after the recording area of each data file,
Even if an unrecorded spare area is provided and the amount of data in the new data file being rewritten is larger than the data file before rewriting, the excess data will be stored immediately in the recording area of the data file before rewriting. Since the new data file is recorded in the subsequent spare area, the new data file can be recorded within a range that does not extend beyond the spare area.

Embodiment FIG. 1 is a block diagram showing a schematic configuration of a data recording/reproducing apparatus in which the data recording method of the present invention is implemented.

The writing and reading circuit 1 includes a rotating drum 2, amplifiers 3 and 4.
It is a circuit including the following, and is arranged on the circumferential surface of the rotating drum 2.../do w1. The magnetic tape T, which is a recording medium, is sequentially scanned by w2 and the reproducing heads R'l and R2, data is sequentially recorded on the magnetic tape T by the scanning of the recording heads Wl and W2, and data is recorded sequentially on the magnetic tape T by the scanning of the reproducing heads R1 and R2. It has the function of reading recorded data on tape T. The signal processing circuit 5 has the function of converting externally input data into a signal suitable for recording and providing it to the write/read circuit 1, and converts the data read from the magnetic tape T by the write/read circuit 1 into a signal suitable for recording. This is a circuit that has the function of converting into a signal and outputting it. The control circuit 6 is a circuit for controlling the operation timing of the write/read circuit 1 and the signal processing circuit 5.

FIG. 2 is a schematic diagram showing the arrangement of data recorded on a magnetic tape T, which is a recording medium, by a data recording method that is an embodiment of the present invention. Among them, FIG. 2 (1) shows the arrangement of data initially recorded on the magnetic tape T on which no data is recorded, and FIG. 2 (2) shows the arrangement of arbitrary data recorded on the magnetic tape T. The data arrangement when file F(i) is rewritten to another data file F(I) having a different amount of data is shown.

FIG. 3 is a flowchart showing the procedure of the data recording method of this embodiment. The data recording method of this embodiment will be explained below with reference also to FIG.

First, in the data recording operation shown in FIG. 3(1), following the start of step n1, a data file is first recorded on the unrecorded magnetic tape T in step n2, as shown in FIG. 2(1). That is, the data processed by the signal processing circuit 5 is sequentially written onto the magnetic tape T by the recording heads Wl, W2 of the rotary drum 2 in the write/read circuit 1. At this time, each data file F(i-1) is recorded on the magnetic tape T as shown in FIG. 2(1).

F (i) and F (i+1) each represent a collection of related data.

Each data file is composed of a plurality of data blocks including data blocks to which parity for error detection/correction is added. For example, in the case of data file F(i), three data blocks Di1. Di2
．． Di3, and are recorded on the magnetic tape T in this order.

In the next step n3, following the recording area of the data file, a spare area SP with no recording for three data blocks is added as an area attached to the data file.

Following the recording of one data file, the next step n
4, a file mark M is recorded to distinguish the data file from the next data file.

It is confirmed whether or not all data files have been recorded by the judgment in step n5. If it is judged that the recording has not been completed, the operations of steps n2 to n4 are repeated, so that each data file is recorded on the magnetic tape T. File F(il
), F(i), F(i+1>,... are recorded sequentially,
If it is determined in step n5 that the data file recording operation has ended, the process moves to step n6 and the data recording operation ends.

Next, when rewriting a desired data file from among the data files previously written on the magnetic tape T,
As shown in FIG. 3(2), following the start of step n7, a search for a data file to be rewritten is performed in step n8. When a desired data file, for example data file F(i), is retrieved, a new data file F(r) having a larger amount of data than that data file F(i) is searched, as shown in FIG. 2(2). Re-recording is performed to rewrite the data. Here, we will create a new data file F(I
) has a data amount larger by 2 data blocks than the data file F(i) before rewriting, so 3 data blocks DI 1. DI2.
DI3 is written over the old data, and a new data file F (I
) remaining two data blocks DI4. DI5 is written.

Next, in step nlo, it is determined whether all the data files to be rewritten have been rewritten,
If the rewriting is not completed, step n8. n
The operation in step 9 is repeated, thereby sequentially rewriting other desired data files with new data files. Further, when it is determined in step nlO that the process has ended, the process moves to step nil, and the data recording process ends.

In this way, the new data file F(I) and the file mark M associated with it are recorded without overlapping with the next data file F(i+1>).

In the above embodiment, the case where an area for 3 data blocks was allocated as the spare area SP was shown, but -
For boat fishing, an area for an integer number of data blocks is reserved as a reserve area S.
It may be assigned as P.

Effects of the Invention As described above, according to the data recording method of the present invention, when recording data on a recording medium for the first time, a pre-(if public area) is provided after the recording area of each data file, and the data file before rewriting is recorded. When rewriting the data file to a new data file with a larger file length, the excess data that protrudes from the data file before rewriting is written to the spare area, so the rewriting of the data file erases recorded file marks and This can prevent other data files from being corrupted.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a schematic configuration of a data recording/reproducing apparatus in which the data recording method of the present invention is implemented, and FIG. 2 is a block diagram showing the general configuration of a data recording/reproducing apparatus in which the data recording method of the present invention is implemented. Fig. 3 is a schematic diagram showing the data arrangement; Fig. 3 is a flowchart showing the procedure of the data recording method;
This figure is a schematic diagram showing the arrangement of data recorded on a magnetic tape by a conventional data recording method, and FIG. 5 is a schematic diagram showing the arrangement of data recorded on a magnetic tape by another conventional data recording method. T...magnetic tape, F (i-1), F (i),
F(i+1>, F (I)...data file, Di
l~Di3. DII to DI5 data block, M.
・File mark, SP・・Reserve area agent Patent attorney Number of strokes Keiichi E (2)

Claims (1)

[Claims] In a data recording method on a recording medium used in a sequential access type data recording and reproducing device that reads out target recorded data according to the recording order, when data is first recorded on the recording medium, related data is read out in accordance with the recording order. For each recording of each data file, which is a collection of This data recording method is characterized in that when rewriting to another data file with a large amount of data, data that protrudes from the data file before being rewritten is written in a spare area so that writing of the data file is contained within the spare area.