JPS6122488A - Information memory system - Google Patents

Abstract

PURPOSE:To correct and add apparently recorded data on unrewritable recording medium and to attain a high speed reading by constituting the titled system in such a way that a directory part provided for data retrieval can be renewed. CONSTITUTION:A directory part for data retrieval is provided, and a new data file AF1 is recorded in non-used area when the directory part is corrected such as correcting data and adding files. Then, the directory part is corrected when necessary, and a new directory D1 is recorded in non-used area. Next, an address of the directory part D1 is recorded in non-used block followed by an old directory D0, and afterwards data is accessed with use of the directory part D1. In order to modify the data again, a renewed new directory part is recorded after new data is recorded in the same manner. Then an address of the new directory part is recorded in a block of the old directory part next to the old directory part.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an external storage device using a storage medium such as a disk or an optical tape that can be played back and recorded only once and is not rewritable. The present invention relates to an information storage method of a storage device suitable for later additional recording of information.

[Background of the invention]

As a method of recording information using a non-rewritable optical disc, as shown in Japanese Patent Laid-Open No. 56-25278, the disc is divided into an index area and a data storage area, and data is stored in the data storage area. Additionally, a method is known in which search data corresponding to each piece of data is recorded in an index area. This method has the advantage that arbitrary data can be accessed quickly and randomly using the search data in the index area.

However, if there is not a one-to-one correspondence between the amount of data to be recorded and the area for search data prepared in the index area, dividing the data storage area and index area in advance will make the entire disk area effective. Difficult to utilize. For example, if the amount of data is large and the data storage area occupies a large portion, but there is a large amount of data that does not require search data, the index area may be left unused. Conversely, if there is a lot of data that does not occupy much of the data storage area,
The index area is filled first and the data storage area becomes unavailable.

Furthermore, as a method of apparently rewriting data that has already been recorded, for example, as shown in Japanese Unexamined Patent Publication No. 56-22274, data to be corrected is recorded in an unused recording area. However, a method is known in which information indicating that correction is to be performed is added to search data corresponding to data to be corrected.

However, although this prior art discloses a method for recording search data on a rewritable floppy disk, it does not provide details on a method for recording search data on a non-rewritable optical disk.

[Purpose of the invention]

An object of the present invention is to provide a data recording method that can apparently correct and add data recorded on a non-rewritable recording medium and read out the corrected or added data at high speed. It's about doing.

[Summary of the invention]

A feature of the present invention is that a directory section for data search is provided, which enables high-speed access to data, and when it becomes necessary to modify the directory section, such as by correcting or adding data, the data can be saved. By recording a new directory part in the recording area and recording the address of the new directory part in the next recording unit (usually a sector) of the old directory part, the directory part can be updated one after another. 0 [Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be shown in FIG. 1 and below, and its operation will be explained. In FIG. 1, 1 is an optical disk for recording data; 2 is an actuator that can move an optical pickup in three directions for recording and reproducing data;
3 is a spindle motor for rotating the disk 1; The optical pickup actually consists of a laser oscillator 7 and a light receiving element 10. Reference numeral 11 denotes a mechanism control circuit, which includes 7 single-occupancy servo circuits 12 tracking servo circuits 13. Through the motor servo circuit 14, the actuator drive circuit 15. The motor drive circuit 16 is controlled so that the disk 1 and the optical pickup maintain a normal relative positional relationship.

Reference numeral 4 denotes a control circuit, which controls the entire apparatus shown in FIG. 5 is an encoder circuit for error correction code (BCC code), 6 is a laser oscillator drive circuit, 9 is an amplifier circuit, and 8 is a decoder circuit for error correction code. When recording data, for example, 288 bytes of ECC code for error correction are added to the original data of 2 bytes, and the data is recorded on the disk by the laser drive circuit 6 and the laser oscillator 7. . Recording is done in sector units, and one sector currently contains 2 bytes of original data, 288 hide BCC code,
and several bytes of information to represent the sector address. When reproducing data, one sector worth of data on the disk is sent to the decoder circuit 8 by the light receiving element 10° amplifier circuit 9. The decoder circuit is
If an error occurs in the data, the error is corrected using an FCC code, and then the necessary 2-byte information is output.

FIG. 2 shows the arrangement of data on the disk.

A disk has a plurality of concentric tracks or a single spiral track, and each track is further divided into several sectors. These sectors can further be arranged in a fixed order. A directory part is recorded in the first sector. FIG. 3 shows the structure of the directory section. At the beginning of the directory, an 8-byte unique code 1D50 indicating that it is a directory is recorded, and an 8-byte FN51 indicating the number of files stored in the disk is also recorded. Starting from the 33rd byte, 62 bytes of search data are recorded for each file. The search data is an 11-byte FN representing the file name.
32, 1 byte A33° representing file attributes, 4 bytes each of address 5A34 of the first block in which the file is recorded, and FL35 representing file size.

For blocks, sectors are used as they are, or integral multiples of sectors are used as one block.

There is no limit to the size of the directory section, and it may span multiple blocks depending on the size of the file. 66 is a code indicating the end of the file, and φφ is recorded therein.

The next block 21 of the directory section 20 is left unused, and files are sequentially recorded starting from the next block. In the example of FIG. 2, files 22 to 26 are recorded from F(1) to P(rL). 27 is an unused area. When reading a file, the directory section is first read, the directory is searched by the file name, necessary data such as the data start address is obtained, and the target data file can be immediately read out.

When correcting data or adding files, a new data file AF(1) is first recorded in an unused area as shown in FIG. Next, modify the directory section as necessary (in the case of data correction, change the file start address 8A and file size PL to those of the new file AP (1), and In the case of addition, the number of files is increased by one and 32 bytes of new file data are added to the directory.) This new directory D(1) is recorded in an unused area. Furthermore, the address of the new directory section D(1) is recorded in the next unused block of the old directory D(0). Thereafter, data is accessed using the new directory section D(1).

If you want to change the data again, record the new data in the same way, record the updated new directory and section, and then record the address of the new directory section in the next block of the old directory section. .

Since a new directory is created each time data is updated, it is preferable to update data all at once.

FIG. 5 shows such an example. Four files AP(2) to AF(s) are added and recorded in the side numbers D(2) and D(d) in FIG.
Data PD(2) indicating the address of (2) is recorded. PD(2) is recorded in the next block ζ of the old directory portion D(1).

It is desirable that the new data, directory section, and new directory address be recorded in this order. This is because there may be a case where there is a defect on the disk and data cannot be recorded. As shown in Figure 6, new data AP' (→52 is recorded and this data is immediately reproduced. At this time, a serious error occurs due to a defect on the disk, etc.), and the error correction code If the data cannot be decoded using , record the data AF (→'53) again. When the data AP (→' can be played back), record the updated directory D(yL+1) 54 for the first time. The new file address is AF(m
)' address is used. If you do this, the file AF (→) that could not be played will be automatically excluded from the file. Even in the case of recording the directory part, it will be read after recording, and if a serious error has occurred, it will be read again. Record the directory part. As shown in FIG.
1) After confirming that ' is reproducible, D(rL+
1) Record the address of ' in PD (yz+1) 51.

Although a replacement block is not prepared for PD(rL+1), it is only necessary to record the address of D(rL+1) in PI)(n+1), so the address can be recorded multiple times. put. Then, even if a serious error that cannot be corrected by the error correction code occurs, the location where the error occurred can be detected, and the correct address of the directory section D(rL+i) can be found from the location where the error does not occur. Can be read.

Since a new directory section is recorded each time data is corrected, it is necessary to find the latest directory section, which is the first directory section D (0).
) The latest directory section can be detected by sequentially going through the addresses starting from PD(1) of the next block.

In the latest directory section, the next block is unused, and the address of the next directory section is recorded in the other directory sections. In addition, the latest directory section is detected only once after the power is turned on.
After that, the address can be recorded in R and AM in the main body, so the time required for data access does not increase.

When deleting data or changing the name of data, it is possible to do so in the same way as correcting or adding data by simply updating the directory section.

The embodiment shown in FIG. 1 describes the case where an optical disc is used as the recording medium, but if the recording medium is non-rewritable,
It can be used in exactly the same way, and the present invention can also be applied to, for example, optical tape.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to apparently correct, add, and erase data even though a non-rewritable recording medium is used. In addition, since the IJ section is always updated in its complete form, the time required to access data does not increase. Furthermore, there is no limit to the number of data files, and it is possible to increase the amount of data until the entire recording medium is used up.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention; FIGS. 2, 4, 5, 6, and 7 are explanatory diagrams showing data arrangement according to the present invention; The figure is an explanatory diagram of a directory section according to the present invention. 1. Optical disk, 2. Actuator, 6.
・Spindle motor. Notebook 1 Zume 20 Notebook 3 Zugun Juzu No. 7

Claims (1)

[Claims] In a storage device using a reversibly non-rewritable medium, 1
If two or more pieces of data and a directory section containing address information for each piece of data are recorded on the same storage medium, and data is to be corrected, added to, deleted, or renamed, as necessary. new data is recorded in an unused area of the medium, a new directory part that has been updated is recorded in the same unused area of the medium, and new data is recorded in an unused area of the medium adjacent to the old directory part. An information storage method characterized by recording an address of a new directory section.