JPH04259958A - Disk-shaped storage device - Google Patents

Abstract

PURPOSE:To prevent a program from being illegally copied or used by comparing a key code written in a gap area with a code set in advance and inhibiting access to data in a valid data area when those codes are not coincident. CONSTITUTION:An interruption processing is started by generating interruption at a microcomputer CPU with the fall of an index pulse from a light receiving device SNS. First of all, a read circuit RDC is activated, an invalid area is read, and the read code is compared with the key code set in advance. Next, when the codes are coincident, 'normality' is set and when they are not coincident, 'abnormality' is set. Afterwards, a key code read flag is turned on, and a main program processing is executed. In the case of normality, the main body of the program in the valid data area is read by turning off the above- mentioned flag and in the case of abnormality, an error processing is executed and finished.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique that is particularly effective when applied to magnetic recording technology and an access control system for floppy disks, for example, a technique that is effective when applied to a data protection system for floppy disks.

0002

2. Description of the Related Art A floppy disk has an index hole formed therein for detecting the rotational position, and this index hole is detected by a photoelectric detector to generate an index pulse as a signal indicating the starting point of a track. It controls access to floppy disks. Conventionally, in a floppy disk, areas Gap1 and Gap2, called gaps, were provided before and after an index hole, respectively, as shown in FIG. Among these, the gap Gap1 is provided to deal with the detection error of the index hole, and the synchronization pattern is 1.
Approximately 6 bytes are recorded. On the other hand, the gap Gap2
is provided to deal with deviations in the rotational speed of the disk over the entire circumference of the track. Therefore, the data stored on the floppy disk is stored in the gap Gap1 as shown in FIG.
is stored in the effective area DTE from Gap2 to the gap
0 Fixed magnetic disk storage device specifications/instruction manual” No. 3
(See pages 6 to 39).

0003

[Problem to be Solved by the Invention] In conventional floppy disk devices, data stored in the effective data area DTE can be easily read, so it is difficult to prevent illegal copying of developed programs. The problem was that it couldn't be done.

An object of the present invention is to provide a floppy disk access control system that can prevent unauthorized copying and unauthorized use of programs. The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[0005]

[Means for Solving the Problems] Representative inventions disclosed in this application will be summarized as follows. In other words, the control system is configured so that the read circuit or read/write circuit is enabled by the edge of the index hole detection pulse, and a key is placed in advance in the invalid area (gap) before and after the index hole, which is not conventionally used as a data area. A code is stored and made readable, or information regarding access such as the number of times of use and number of backups is stored.

[0006]

[Function] Conventionally, the length of the gap before and after the index hole has been set to about 10-odd bytes, but with the development of hardware, the length of the gap required to deal with index pulse detection errors and rotation speed deviations has increased. The length is now only a few bytes. Therefore, by the means described above, it is possible to store several bytes of key code and access information in the gaps before and after the index hole, and also to use a general-purpose disk controller LS in the control system.
A normal disk device using I does not read the code in the gap before and after the index hole, so the code stored in the gap is not copied. Therefore, when the program is started, it is possible to check the gap code and, if there is no correct key code, to stop the execution of the program, thereby achieving the above-mentioned purpose of preventing unauthorized copying or use of the program.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 schematically shows an embodiment of a floppy disk device according to the present invention. In Figure 1,
The symbol FD indicates a floppy disk, CP
U is a microcomputer, and CNT is a magnetic head H
A head control circuit RD that drives a stepping motor STM for moving D in the radial direction of the disk, a disk rotation motor (not shown), and controls the elevation and descent of the head.
C and WTC are read and write circuits that drive read and write heads to read and write magnetic data on the disk. In addition, there are index holes IHL on the top and bottom of the floppy disk FD.
A pair of light emitters LED and a light receiver SNS constituting the rotational position detecting means are arranged to face each other in correspondence with the position of the head. It is supplied to the control circuit CNT and the microcomputer CPU. In this embodiment, the index pulse IDX is input to the microcomputer CPU as an interrupt signal,
A microcomputer CPU is configured to control a read circuit RDC and a write circuit WTC based on the interrupt signal.

FIGS. 2 and 3 show an example of the interrupt control procedure by the microcomputer CPU. Further, FIGS. 4 and 5 show the structure of a storage area when data is stored on a disk by the floppy disk device of the above embodiment. According to this embodiment, the storage area KEY where the key code is stored immediately after the index hole IHL, that is, between the gap Gap2 and the starting end of the effective data area DTE, and the gap Gap1.
are provided consecutively. A key code is stored in advance in the storage area KEY, and a synchronization pattern is stored in gaps Gap1 and Gap2. The above key code can be stored in any or all tracks on the disc.

Next, the operation of the microcomputer CPU will be explained using FIGS. 2 and 3. When the system is started, the disk control circuit CNT starts the disk rotation motor, brings the magnetic head into contact with the disk, reads the synchronization pattern, and controls the rotation speed to be constant. On the other hand, the microcomputer CPU starts the main program processing shown in FIG. 2 when the system is started. Then, by first setting the interrupt enable flag to enable interrupt processing (step S1), and then checking the key code read flag and waiting until the flag turns on, you can wait for the result of the interrupt processing in Figure 3. (Step S2). The interrupt process in FIG. 3 is started by an interrupt occurring in the microcomputer CPU due to the fall of the index pulse IDX from the photoreceiver SNS.First, the read circuit RDC is activated and the invalid area (
Gap1) is read (step S11).
). Next, the read code is compared with a preset key code to determine whether they match (step S12). Then, if the codes match, the comparison result will be marked "normal", and if they do not match, the comparison result will be marked "normal".
After setting "Abnormal", turn on the key code reading flag and return to the main program processing (steps S13, S1
4, S15). When the key code reading flag is turned on in the interrupt processing, the main program processing moves to step S3, and determines whether the comparison results set in steps S13 and 14 above are normal or abnormal, and if normal, the key code reading flag is turned off. After that, the main body of the program in the effective data area DTE is read (steps S4 and S5). On the other hand, if the comparison result is abnormal, error handling is executed and the process ends (step S6). This prohibits the execution of illegally copied programs and also prevents illegal copying of programs.

FIG. 6 shows an embodiment in which prevention of unauthorized reading of the program is realized by hardware. In this embodiment, the microcomputer C
As the external circuit of the PU, the same code as the key code of the storage area KEY in the gap of the disk is set.
A read data holding means DTH consisting of a setting means KST such as an OM (read only memory), a serial-parallel converter that converts the data read by the read circuit RDC into parallel data, and a register that holds the converted data. And this read data holding means DT
A comparator CMP is provided which compares the data held in H with the code set in the setting means KST. The read data holding means DTH is supplied with a detection pulse IDX from the light receiver SNS that detects the index hole IHL, and is configured to take in and hold read data from the read circuit RDC in synchronization with the falling edge of this pulse. It has become. Then, when the read data is taken into the read data holding means DTH, the data and the code set in the setting means KST are compared by the comparator CMP. As a result, if it is determined that they do not match, an interrupt signal IRQ is input to the microcomputer CPU. When the microcomputer CPU receives an interrupt signal, it executes error processing and, for example, reads the read circuit RD.
It is configured to disable C and stop reading the effective data area of the disk.

In this embodiment, although not particularly limited, the write circuit WTC is controlled to set the key code set in the setting means KST on the disc in synchronization with the fall of the detection pulse IDX from the light receiver SNS. The function of writing to the storage area KEY in the gap is the microcomputer CP.
It is located in U. In the above embodiment, it has been explained that the setting means KST is constituted by a ROM, but it may be constituted by a RAM (random access memory) or a register so that the key code can be set programmably.

Further, in the above embodiment, a protection key code is stored in the storage area KEY in the gap of the disk, but the software of the microcomputer CPU allows the storage area Read the KEY data and select “
By adding ``1'' and writing it in the original position,
It is also possible to use the storage area KEY as a counter. This makes it possible to prevent unauthorized use by storing the number of times a program has been loaded on the disk and prohibiting reading when a predetermined number of times has been reached.

As explained above, in the above embodiment, the control system is configured so that the read circuit or the read/write circuit is enabled by the edge of the index hole detection pulse. A key code is stored in advance in the invalid area (gap) before and after the hole to make it readable, or information regarding access such as the number of uses and backup times is stored, so a few bytes are stored in the gap before and after the hole. In addition to being able to store key codes and access information, ordinary disk drives that use a general-purpose disk controller LSI for the control system do not read the codes in the gaps before and after the index hole, so the codes stored in the gaps can also be stored. is not copied. Therefore, it is possible to check the gap code when starting the program and stop the program execution if the correct key code is not found, which has the effect of preventing unauthorized copying or use of the program.

[0014] The invention made by the present inventor has been specifically explained based on examples, but the present invention is not limited to the above-mentioned examples, and can be modified in various ways without departing from the gist thereof. Needless to say. For example, in the above embodiment, the read circuit RDC and the write circuit WTC are directly controlled by the microcomputer, but the control of the read circuit and the write circuit is left to the control circuit CNT, and the microcomputer controls the control circuit CNT.
It is also possible to provide a configuration in which only a command to enable or disable the control of the read circuit and write circuit by the controller is given. In the above explanation, the invention made by the present inventor was mainly applied to a floppy disk device, which is the background field of application. Type storage devices can be used in general.

[0015]

Effects of the Invention The effects obtained by typical inventions disclosed in this application are briefly explained below. That is, it is possible to prevent unauthorized copying or use of programs in the disk storage device.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of an embodiment of a floppy disk device to which the present invention is applied.

FIG. 2 is a flowchart showing an example of main program processing of the floppy disk device of the embodiment.

FIG. 3 is a flowchart showing an example of an interrupt processing program of the floppy disk device according to the embodiment.

FIG. 4 is an explanatory diagram showing an example of the configuration of a storage area of a floppy disk used in the floppy disk device of the embodiment.

FIG. 5 is an explanatory diagram showing an example of a track format of a floppy disk used in the floppy disk device of the embodiment.

FIG. 6 is a schematic configuration diagram of a floppy disk device according to a second embodiment of the present invention.

FIG. 7 is an explanatory diagram showing an example of a configuration of a storage area of a floppy disk used in a conventional floppy disk device.

FIG. 8 is an explanatory diagram showing an example of a track format of a floppy disk used in a conventional floppy disk device.

[Explanation of symbols]

FD floppy disk IHL index hole CPU Microcomputer CNT head control circuit STM head drive motor LED light emitter SNS Photoreceiver CMP comparator

Claims (3)

[Claims] 1. A drive means for rotating a magnetic disk, a rotational position detection means for detecting an index hole provided in the magnetic disk, and a position of the magnetic head is controlled based on a detection pulse from the rotational position detection means. In a disk type storage device, the detection pulse is inputted to an interrupt terminal of a microcomputer, and interrupt processing is started at the edge of the pulse. It is configured to enable the read/write means, read the key code written in the gap area on the magnetic disk, compare it with a preset code, and prohibit access to data in the effective data area if it does not match. A disk-type storage device characterized by: 2. A drive means for rotating a magnetic disk, a rotational position detection means for detecting an index hole provided in the magnetic disk, and a position of the magnetic head is controlled based on a detection pulse from the rotational position detection means. In a disk type storage device, the detection pulse is inputted to an interrupt terminal of a microcomputer, and interrupt processing is started at the edge of the pulse. A disk type storage device characterized by being configured to write information regarding access in a gap area. 3. Drive means for rotating a magnetic disk, rotational position detection means for detecting an index hole provided in the magnetic disk, and control of the position of the magnetic head based on detection pulses from the rotational position detection means. A disk type storage device comprising: a control means for controlling the magnetic head; and a read/write means for driving the magnetic head; A key code storage means for storing the set key code and a comparison means for comparing the read data and the key code are provided, and a coincidence detection signal from the comparison means is inputted to an interrupt terminal of the microcomputer to detect the coincidence. A disk type storage device characterized in that an interrupt process is started in response to a signal to prohibit access to data in an effective data area.