JPH0731903B2 - Data recording method - Google Patents

Description

The present invention relates to a data recording method, and more particularly to an information recording medium having a data recording section and a directory recording section, in which a plurality of data files are stored in the data recording section. The present invention relates to a data recording method of recording directory information corresponding to each data file in the directory recording unit in order to record and manage the recorded data file.

[Prior Art] Conventionally, as an information recording medium, a floppy disk for recording / reproducing by using magnetism, an optical information recording medium for recording / reproducing by using light (hereinafter referred to as an optical card), etc. are known. ing.

These information recording media use auxiliary data, so-called directories, which manage data for each file in order to store a large amount of data. Normally, file information such as a file name, file length, head data track number, etc. is written in the directory to manage files in the data track section.

The above-mentioned optical card, particularly the non-erasable additional optical card, has a large recording capacity even if it is as small as a credit card. The size of a credit card is about 85
mm × 55 mm, when the information track pitch is 20 μm and the 1-bit recording length is 5 μm, the number of tracks 55 × (1000 ÷ 20) = 2750 (lines) Bit capacity / track 85 × (1000/5) = 17000 (bit) byte capacity / track 17000/8 = 2000 (bytes). Therefore, the total data capacity is 2750 x 2000 = 5500000 = 5.5 (MB).

In order to manage such a large amount of information, it is necessary to use a directory information management method.

FIG. 7 is a schematic plan view showing an example of an optical card.

As shown in FIG. 7, the optical card 1 has a data section 10 (10 1,10 2, ..., 10 n) consisting of data tracks and a directory section 20 (20 1,20 2, ..., 20 n). Are provided to write data in the E direction from the upper portion of the optical card in the E direction, and write directory information as data management information in the D portion from the lower portion of the optical card 1 in the D direction by a write-once method.

[Problems to be Solved by the Invention] In the above directory management method, if even a part of the directory is damaged and becomes unreadable, the file control information will be erased. Although it can be read normally, there is a problem that the file control becomes impossible and, as a result, the contents of the data recording portion are largely damaged.

It is an object of the present invention to provide an information recording system capable of correctly reading a data recording section corresponding to a defective directory even if the defective directory exists.

[Means for Solving the Problems] The above problems are caused by using an information recording medium having a data recording section and a directory recording section, recording a plurality of data files in the data recording section, and recording the recorded data. In a data recording method of recording directory information corresponding to each data file in the directory recording unit to perform file management of the file, the directory information is recorded in the directory recording unit and is the same as at least a part of the directory information. By recording the information of the above in the corresponding data file of the data recording unit, when the predetermined directory becomes unreadable,
The data recording method according to the present invention is characterized in that the predetermined directory can be restored using the directory information recorded in the data file corresponding to the predetermined directory.

[Operation] According to the present invention, by recording at least a part of the directory information for file management in the data recording unit, even if a defective directory exists in the directory management unit, it is recorded in the data recording unit. It reads a directory and enables file control.

EXAMPLES Examples of the present invention will be described below in detail with reference to the drawings.
In the following description, an optical card will be taken as an example of the information recording medium.

First, a configuration example of the information recording / reproducing apparatus used in the data recording method of the present invention will be described.

FIG. 6 is a schematic diagram of a configuration example of an information recording / reproducing apparatus used in the present invention.

An information recording / reproducing device (hereinafter referred to as a drive) 31 is connected to a host controller (hereinafter referred to as a host) 32, and performs data communication and control between the drive 31 and the host 32.
The MPU 33 in the drive 31 has built-in ROM and RAM, and mainly controls the card feed motor 37 and head feed motor 36,
The AT / AF control circuit 34 receives the signal from the photodetector 39 and drives the AF actuator 40 and the AT actuator 41. Further, the modulation / demodulation circuit 35 executes recording by changing the emission intensity of the light source 38 during recording, and demodulates data based on the signal of the photodetector 39 during reproduction. The host 32 transmits / receives data to / from the drive 31, and the directory section on the optical card 1,
It controls the writing and reading operations of information in the data section.

Next, a directory recording method and a reproducing method according to an embodiment of the data recording method of the present invention will be described with reference to a flowchart.

FIG. 1 is a flowchart showing a method of recording a directory.

FIG. 3 is an explanatory view showing the data recording section.

FIG. 4 is an explanatory view showing the directory section.

As shown in FIG. 1, file data is recorded for each track from the beginning of the file in order from step T1 to step T2, and the final data is recorded at step T3. In this file data, as shown in FIG. 3, in addition to user data (data to be recorded by the user program), some information regarding the user data is hosted.
The data automatically added by 32 is recorded as file data for each track. In this embodiment, one file is composed of m data tracks (100 1 to 100 m).

Then, in step T4, the directory is recorded in the directory recording unit. As shown in Figure 4, the directory
In addition to information such as a normal file name 201 and date 202, 200 includes information indicating the size (length) 203 of file data.

As the information added to the file data, the same information as this directory is added, but the information indicating the size of the data is not added except for the final track data. Alternatively, even if a recording area indicating the size of data is provided, meaningless information such as “0” is recorded. This is to cope with a system in which the size of the file does not determine until the last data is recorded, that is, a data variable length file.

By recording the information indicating the size of the file data only in the final track, it is used for data recovery when the directory, which will be described later, cannot be read.

The reproducing method of the directory portion of the optical card recorded by the above method is performed as follows.

FIG. 2 is a flow chart showing a method of reproducing a directory.

As shown in FIG. 2, in step S1, the directory is read, and in step S2 it is checked whether there is a read error. If the data can be read normally, the file data recorded in the data section is read. Step S2
If there is a reading error in step S3, the process goes to step S3 and subsequent directory recovery processing.

As described above, in the present embodiment, since the directory recording unit and the data recording unit are the additional recording system, the file next to the last track of the file indicated by the directory before the errored directory is indicated by the errored directory. It is the first data track. Therefore, in step S3, the directory before the directory having the read error is read, and in step S4, the first data track of the file indicated by the directory having the error obtained in step S3 is read. Based on the directory information written in each data track, it is determined in step S5 whether the information is the end of the file. If not the last
The next data track is read in step S6, and the process is repeated from step S5. If the track is the final one in step S5, the file length is fixed depending on how many tracks are read, and the process proceeds to step S7 to recover the directory.

In this embodiment, since the data length of the file is determined when all the data tracks have been written, the directory information written in the data recording section does not include the file length, but the file length is determined from the beginning. In the system, by writing the file length in the directory information of the data section, steps S5 and S6 in FIG.
Can be omitted.

Also, in FIG. 2, the data track number of the file indicated by the error directory is determined by reading the directory before the error directory in steps S3 and S4, but the same thing can be done by reading the directory next to the error directory. realizable.

Although the directory information of each data track is recorded in each data track in the above embodiment, it is also possible to record the directory information for each file in a part of the data recording section.

FIG. 5 is a schematic plan view of an optical card when directory information is recorded in the data recording section for each file.

As shown in the figure, the data track 2 1,2 2,2 3 forms a file 4, and the directory information of the file 4 is recorded in the directory portion 3 1. The information in the directory section 31 is recorded in the leading end recording area 5 of the file 4. In this embodiment, since the directory information is recorded for each file, the directory information is not emphasized and the data portion is efficiently used as compared with the case where the directory information is recorded in each data track. be able to.

Since the method of recording / reproducing the directory is the same as that of the above-mentioned embodiment, its explanation is omitted.

In this embodiment, the information in the directory portion is recorded in the leading end recording area of the file, but it may be recorded in any location in the data portion of the file as long as it is a predetermined location.

[Effects of the Invention] As described in detail above, according to the data recording method of the present invention, even if an important directory for file management in the data section is damaged and becomes unreadable, The information recorded in can restore the directory without damaging the data files. As a result, highly secure data recording can be performed.

[Brief description of drawings]

FIG. 1 is a flowchart showing a method of recording a directory. FIG. 2 is a flow chart showing a method of reproducing a directory. FIG. 3 is an explanatory diagram showing the data part. FIG. 4 is an explanatory view showing the directory section. FIG. 5 is a schematic plan view of an optical card when directory information is recorded in the data section for each file. FIG. 6 is a schematic diagram of a configuration example of an information recording / reproducing apparatus used in the present invention. FIG. 7 is a schematic plan view showing an example of an optical card. 31 …… Drive 32 …… Host 100 1-100m …… Data track 200 …… Directory S1-S7 T1-T4 …… Step

Claims (1)

[Claims] 1. An information recording medium having a data recording section and a directory recording section is used to record a plurality of data files in the data recording section and to manage the recorded data files. In the data recording method of recording the directory information corresponding to the above in the directory recording section, the directory information is recorded in the directory recording section, and the same information as at least a part of the directory information is recorded in each data recording section. By recording in a file, when the predetermined directory becomes unreadable, the predetermined directory can be recovered using the directory information recorded in the data file corresponding to the predetermined directory. Data recording method.