JPS6320770A - Optical disk - Google Patents

Abstract

PURPOSE:To enable the light protection of high reliability strong even for a soft error by providing the information showing a ROM part, RAM part and one part of the zone range on an optical disk and prohibiting the rewriting of the ROM part. CONSTITUTION:A ROM part 5 and RAM part 6 are provided on an optical disk 1, the information showing the one part of the zone range thereof is provided as well and this information is read by an optical pickup head 10 and fed to a disk controller 12 via a signal reading circuit 11. It is then compared by a comparison part 22 with the storage contents of a boundary position storing part 21 and the erasing and writing by the head 10 are prohibited for the ROM part 5 via a laser driver 13. With this prohibition by hardware, the light protection of high reliability strong even for soft errors can be executed.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to an optical disc on which data can be recorded and reproduced optically.

B8 Summary of the Invention The present invention provides an optical disc that can be recorded and reproduced.
A so-called RAM area in which signals can be recorded and reproduced and a so-called ROM area in which only signals can be reproduced coexist on the same disk, and information indicating the range of at least one of these areas is recorded on the disk. By storing this information, rewriting or erasing of the recorded information in the ROM area is prohibited based on this recorded information, thereby realizing strong write protection.

C6 Conventional technology Programs for performing desired data processing, especially O3
(operating system), various programming languages, simple programming languages, basic programs such as word processors, and basic data essential to these programs, such as dictionary data, kanji pattern data, and parameter data for pattern recognition. etc., unlike various general data to be processed, often do not require rewriting processing, and rather some kind of write-protection processing is desired to prevent the content from being rewritten due to operational errors etc. There are many things. For this reason, in magnetic disks such as so-called floppy disks, the basic programs and basic data are protected by a method of specifying whether or not each file is write-protected using software. However, write protection applied by software can be canceled relatively easily by software. may also be written to. Therefore, in order to ensure more reliable protection, a disk on which the program and basic data are recorded is prepared separately from the normal data disk as a so-called program disk.
Mechanical (hardware) write-inhibiting processing using a so-called protect seal or protect notch is often performed on the entire disk.

D1 Problems to be Solved by the Invention Incidentally, in recent years, recording media with extremely high recording densities, such as magneto-optical disks, have been put into practical use. However, preparing a disk exclusively for the program files and making it write-protected is inconvenient in terms of effective use of recording capacity. In other words, the basic program such as the O8 mentioned above is from tens of bytes to hundreds of bytes at the most, and the basic data mentioned above is also generally about several hundred to hide. Even when recording, a recording capacity of several megabytes is sufficient, whereas the above-mentioned optical disc has a recording capacity of several hundred megabytes, which is about two orders of magnitude larger than -S.
As in the case of the Fronbi disc mentioned above, if you try to make one optical disc non-rewritable as a so-called program disc, only a very small portion of the total recording capacity is recorded, and most of the remaining This is extremely uneconomical as this portion remains unrecorded and unused. Therefore, it is necessary to protect against erroneous writing by specifying write prohibition for each file using software, but as mentioned above, there is a drawback that the ability to protect against software errors and the like is low.

The present invention has been made in view of the above circumstances, and aims to provide an optical disc that can realize strong write protection by recording programs and data that should be write-protected on a rewritable optical disc. shall be.

Means for Solving the E1 Problem In order to solve the above-mentioned problems, the optical disc according to the present invention has an optical disc that can record and reproduce signals, an area where signals can be recorded and reproduced, and an area where recorded signals can be recorded. The disc is characterized in that a playback-only area is provided, and information indicating the range of at least one of these areas is recorded at a predetermined position on the disc.

F0 function RA that can record and reproduce signals on the same disk
M SJ\ area and R where only playback of recorded signals is possible.
Since the OM if area and the ROM area are separated, information indicating the range of at least one of these areas can be read out to perform recording and erasing operations when an optical pickup head or the like is located within the ROM area. By prohibiting this using hardware, it is possible to provide highly reliable write protection that is resistant to soft errors and the like.

G. Embodiment Next, an optical disc according to an embodiment of the present invention and a disc device for recording and reproducing the optical disc will be described with reference to FIGS. 1 and 2.

In these FIGS. 1 and 2, the optical disc 1 is
For example, it is capable of recording and reproducing signals optically and magnetically, and a plurality of sectors are formed by dividing concentric or spiral tracks into predetermined lengths or predetermined angles. For these sectors, an ID section 2 in which an ID code including a track address and a sector address is recorded is preformatted (preformatted) at the beginning position of each sector by, for example, so-called embossing. ing. This optical disc 1
A so-called lead-in section or disc ID section 3 is recorded in an area on the innermost trunk side of the disc, and an area adjacent to this disc ID section 3 on the outer circumference side contains index information regarding the recorded contents of the disc. In this embodiment, the recorded TOC (Table of Contents) section 4 is an area from the outer periphery Wa of the TOC section 4 to a point Zb that is a predetermined distance away from the outside. The so-called RO is an area where rewriting and erasing by an optical pink-up head is regulated and only reading is possible.
It is M part 5. The remaining area up to the outermost circumferential position C of the disk is a rewritable RAM section 6 that realizes the original functions of the magneto-optical recording disk 10.

Here, identification information indicating whether the optical disk is of the type having the ROM section 5 or not is written in the disk ID section 3, and when the user starts using the disk system, When performing initialization by a reset operation, etc., the optical pickup first reads out this disc ID section 3 to determine whether the optical disc has the ROM section 5 or not. Further, in the 700 section 4, an inner boundary position la and an outer boundary position of the ROM section 5 are recorded.

Next, the ROM section 5 is controlled by an electrical or mechanical operation regulating means provided in the disk device, which will be described later.
Signals cannot be written or erased using the optical pink-up head.

Such a ROM section 5 is formed by, for example, being recorded by a user by writing a program, data, etc. that the user wants to use only for reproduction from the outer circumferential position a of the 700 section 4 of the disk 1 sequentially toward the outer circumference. After forming the recording in step 5, move the recording end position to a predetermined position on the disk, for example, T.
In addition to the information recorded in the OC section 4, the disk supplier side may store the above-mentioned O8, programming language, simple programming language, or basic software program such as word processor software in the ROM section 5.
Data such as dictionary data and kanji patterns that are indispensable to these programs may also be recorded and optical discs with these software installed may be supplied to the market. In this case, in order to prohibit writing and erasing, the ROM section 5 is provided with an uneven shape or holes by so-called embossing, similar to the ID section of each preformed sector. The signal may also be recorded.

The general configuration and operation of the main parts of the system for performing recording and reproduction on the optical disc 1 on which such recording has been made will be explained.

First, when starting to use the optical disc 1, the optical pickup head 10 scans the disc ID section 3 of the optical disc 1 as described above, and the signal reading circuit 11 reproduces the recorded content. According to this reproduced disk ■D information, the disk controller 12 determines whether the optical disk 1 currently in use is of the type having the above-mentioned ROM section 5 (see steps S1 and S2 in FIG. 3). . If the determination result at this time is No (in the case of a disk that does not have a ROM section), normal disk control operations are performed.

On the other hand, if the determination result is YES, by reading the 700 copies 4 of the optical disc 1, the ROM is
The above-mentioned inner and outer boundary boundary positions a and b of the section 5 are read, and the boundary position information is stored in the storage means 21 in the disk controller 12 (see steps S3 and S4 in FIG. 3), and these boundary position information are also stored. a, b to disk
The data is sent to the comparison unit 22 in the controller 12. Note that data and control number 13 are exchanged with an external host computer 20 via a disk controller within the optical disk device.

Next, during normal disk access, the signal from the optical pickup head 10 in FIG. and this address information is sent to the disk controller 12. At this time, the disk controller 12 determines whether the current operation mode is write or erase mode (step 311 in FIG. 3), and YES C (write or erase mode).
In this case, it is determined whether or not the currently accessed track is within the area between 1a and 1b corresponding to the ROM section 5 (step 312). If the determination is YES, the process proceeds to the next step S13. Proceed to the above ROM section 5
The laser driver 13 and the head movement control circuit 14 are controlled to restrict writing and erasing by the optical pickup head 10 to the optical pickup head 10. That is, laser driver 1
3 is basically capable of controlling the optical pick amplifier head lO so that it can take all modes of read (read), write (write), and erase (erase). When the head is located at , control is performed to prohibit transition to write and erase modes. Also, when recording or erasing mode is selected, is there a head movement system? ] The circuit 14 is controlled to set the optical pickup head 10 to the position a4.
It may be mechanically restricted from moving to the track within the area between b. The head movement control circuit 14 controls the movement of the optical pickup head 1° in the disk radial direction via the head support plate 16 by rotationally driving the head movement motor 15.

In this way, by electrically or mechanically regulating the recording and erasing operations of the optical pickup head 10 on the ROM section 5, the ROM section 5 can be strongly write-protected. Furthermore, R.O.
The user can configure the optical disk and the disk device so that the first recording on the M portion 5 can be formed, so the user can freely select programs and data that he or she wants to write protect on the optical disk 1. It can be recorded on the ROM part 5, and the recorded contents are strongly protected against rewriting or erasing.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and the present invention is not limited to the above-mentioned embodiments; for example, the optical disks include not only those that can be freely rewritten such as magneto-optical disks, but also so-called write-once type or write-once type optical disks. The present invention can also be applied to.

Effect of H0 Invention According to the optical disc of the present invention, RO is recorded on one disc.
The M section and RAM section coexist, and not only can strong write protection be applied to basic data and programs, but also the user can freely record and create programs and data in the ROM section. It is also possible to provide an optical disc that is convenient to use.

[Brief explanation of the drawing]

FIG. 1 is a block diagram schematically showing an optical disc according to an embodiment of the present invention and a configuration for recording and reproducing the optical disc, and FIG. 2 is a schematic plan view showing the optical disc taken out.
FIG. 3 is a flowchart for explaining the operation. l...Optical disc 2...Sector ID section 3...Disk ID section 4...TOC section 5...ROM section 6...RAM section 10...Optical pick amplifier head 11...Signal Reading circuit 12...disk controller 13...laser driver 14...head movement control circuit

Claims (1)

[Claims] An optical disk capable of recording and reproducing is provided with an area where signals can be recorded and reproduced, and an area where recorded signals can only be reproduced, and information indicating the range of at least one of these areas is provided on the disc. An optical disc that is recorded on a predetermined position.