JPH0278065A - Disk medium read/write system - Google Patents

Abstract

PURPOSE:To prevent copying by a third party by adding the same sector number to plural physical sectors on the same track, and regulating the issueing timing of a command according to the position of the sector at the same sector number. CONSTITUTION:It is a physical sector 11-3 that is recognized as a sector 2 after the issueing of a first sector 2 read instruction, and it is a physical sector 11-4 that is recognized as the sector 2 after the second read instruction of the sector 2. Thus, even when the same sector number is allocated to the plural physical sectors by regulating read/write timing according to its position, the data can be read or written to the target physical sector. On the contrary, it is a huge trouble for the third party to know formatted contents, and to copy the medium is difficult. Thus, the unjust copying of the third party can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a read/write method for a disk medium, and particularly to a read/write method for a disk medium that prevents easy copying.

[Conventional technology]

In information processing systems, various disk medium copy prevention means have been devised to prevent programs recorded on disk media from being easily copied and used. One way to do this is to set a specific format on the disk medium that cannot be written by the general L81 for disk control, and write data such as nib programs on this format so that it cannot be copied by general devices. There is a way to do it.

[Line drawing that the invention attempts to solve]

However, even with such means, if a third party illegally or accidentally obtains a disk medium formatted in a specific format, it is possible to copy the program contents relatively easily. In addition, since the contents of the above-mentioned specific format can be known relatively easily, a third party who has a device that can write any format on a disc medium may illegally copy it. If an attempt is made to do so, it will not be possible to prevent this and the damage will be enormous.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the conventional disk medium read/write methods as described above, and to provide a disk medium write/read method that cannot be easily copied by a third party.

[Failure to solve the problem]

The disk medium read/write method of the present invention uses a flexible disk medium (1) in which the same sector number is assigned to a plurality of physical sectors on at least one track, and the same sector number is assigned to a plurality of physical sectors on at least one track. This includes writing or reading data to or from the target physical sector by adjusting the timing of issuing a data read or write command in accordance with the positional relationship of the physical sector to which the data is assigned.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 is a plan view showing the concept of a disk medium.

As shown in FIG. 2, the disk medium 1 has a large number of concentric tracks 11. As shown in FIG. 3 is a format diagram showing an example of a 7-format track on the disk medium shown in FIG. 2 when the present invention is implemented.

In FIG. 3, #l and #2 to #n indicate sector numbers, and 11-1 to 11-m are physical sector numbers given for convenience in order to identify the physical positions of the respective sectors.

A sector number #1 is assigned to the physical sector 11-1, and the same sector number #2 is assigned to the physical sectors 11-2 to 11-4.

FIG. 1 is a flowchart showing an example of an operation when reading a sector on a track of a disk medium according to an embodiment of the present invention, and an example when reading a sector on a track formatted as shown in FIG. shows.

The T1 time at reference numeral 53 in FIG.
This is the time it takes for the magnetic head to come on -2 (+2 sector), and the 13 hours at reference numeral 58 is for physical sector 1.
After reading l-1 (+1 sector), physical sector 1l-3 (+
This is decided by taking into consideration the time it takes for the magnetic head to come over the 2nd sector).

As shown in the flowchart of FIG. 1, after the first sector #2 read command is issued (reference numeral 54), the physical sector 1l-3 (reference numeral 5) is recognized as +2 sector.
5) After the second sector #2 read command (reference numeral 59), the physical sector 11-4 (reference numeral 60) is recognized as +2 sector. As described above), even if the same sector number is assigned to multiple physical sectors, by adjusting the read/write timing according to the position of the sector, it is possible to You can read or write data using On the other hand, if a third party attempts to learn the formatted contents in this way, it will require a great deal of effort, making it extremely difficult to copy the medium. At the same time, reading data on sectors is also extremely difficult for those who do not know the layout of physical sectors.

〔Effect of the invention〕

As explained above, the disk medium read/write method of the present invention uses a disk medium that is formatted so that the same sector number is assigned to a plurality of physical sectors on the same track of the disk medium. By adjusting the timing of issuing data read/write commands in accordance with the positional relationship of multiple physical sectors, data can be written or read correctly in the target physical sector. Therefore, it is possible to prevent a third party from easily copying or reading data or programs on the medium.

[Brief explanation of the drawing]

FIG. 1 is a flowchart showing an example of an operation when reading a sector on a track of a disk medium according to an embodiment of the present invention; FIG. 2 is a plan view showing the concept of the disk medium;
FIG. 3 is a format diagram showing an example of the format of the track on the disk medium of FIG. 2 when the present invention is implemented. 1...disc medium, 11.old...track,
11-1・11-2・11-3・11-4・11-m・
River...Physical sector. Agent Patent Attorney Otode Uchihara

Claims (2)

[Claims] (1) At least 2 in flexible disk media
1. A flexible disk medium having more than one sector of different length on the same truss. (2) A recording method characterized by having at least two or more sectors of different lengths on the same track and writing mutually interpolated data.