JP2003030801A - Data erasing device and data erasing program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device which can rapidly erase the data recorded on a recording medium. SOLUTION: The data randomly formed by a CPU 111 of a control section 11 is stored as random unit data into a memory 112 and the unit data is repetitively and continuously written into a memory 12, by which the recorded data for erasure is constituted. This recorded data is written to a hard disk 21, by which the data recorded to the hard disk is erased. The processing time is shortened by shortening the time for forming the random data for which the processing time of the CPU 111 is sufficiently needed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a program for erasing data recorded on a recording medium such as a hard disk, and more particularly to an apparatus and a program for which the erasing time is shortened.

[0002]

2. Description of the Related Art In recent years, when discarding a personal computer, there has been a problem that recorded data is read and abused after the discard. Normally, when data is erased on the operation screen of a personal computer, the management information of the file in which the data is recorded is only rewritten, and the data itself recorded in the hard disk, which is the recording medium, is erased. Absent. Therefore, it is possible to restore the data by directly reading the location where the data is written.

In order to solve such a problem, it is necessary to completely erase the data. For that purpose, specific data is written in the entire area of the hard disk to physically erase the data. . For example, processing such as recording all 0s or 1s for each bit is performed.

[0004]

However, even if the above-described physical data erasing process is performed, the data may not be completely erased. The digital data is composed of a combination of 0 or 1, and the signal read from the recording medium is binarized as shown in FIG. 4, for example. If all the data in this state is rewritten to 0, as shown in FIG. 5, there is a slight difference in remanence between the position where the value before data erasure is 0 and the position where the value is 1. Will occur.

When reading with a personal computer or the like, all the signals as shown in FIG. 5 are recognized as 0, but if a minute difference is detected by a highly accurate detection device, before the data is detected. It becomes possible to read the value of. In order to completely erase such traces of data, it is necessary to repeatedly perform erasing processing such as rewriting to 0 and then to 1, and a long time is required for the erasing processing.

As a data erasing method that does not leave a trace of data as described above, there is also a method of writing random data (meaningless data). However, it is difficult to erase the data in a short time because the load on the CPU is large and the processing time is long in order to create the random data enough to be written in the entire area of the recording medium. An object of the present invention is to provide a device and a program that can erase digital data in a short time.

[0007]

Such an object is achieved by the present invention described below. (1) Random unit data creating means for creating a predetermined unit amount of random data, recording data creating means for creating erase recording data based on the created random unit data, and created erase recording A data erasing device comprising: a medium recording unit for recording data on a recording medium.

(2) Further, the medium recording means has a memory for accumulating the erasing record data, and the medium recording means records the erasing record data accumulated in the memory on the recording medium.
The data erasing device described in. (3) The recording medium is a hard disk (1)
Alternatively, the data erasing device according to (2).

(4) The data erasing device according to any one of (1) to (3), wherein the predetermined unit amount is 2 bytes. (5) The recording data for erasure is formed by repeating and continuing random unit data.
~ The data erasing device according to any one of (4). (6) The data erasing device according to any one of (1) to (5) above, wherein the recording data creating means records the erasing recording data on the entire area of the recording medium.

(7) Furthermore, the random unit data creating means creates new random data, the recording data creating means creates new erasing record data, and the medium recording means creates new erasing record data. The data erasing device according to any one of (1) to (6) above, further comprising erasing process control means for setting the number of erasing processes for the erasing process including writing to the entire recording medium.

(8) A first step of creating a predetermined unit amount of random data, a second step of repeatedly connecting the created random unit data to create erase recording data, and the created erase A data erasing program, including a third step of recording recording data for recording on a recording medium. (9) The data erasing program according to (8), wherein the first step to the third step are repeated a plurality of times.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described in detail below. FIG. 1 is a block diagram showing the configuration of a data erasing device 1 of the present invention. The data erasing device 1 of the present invention is a device for erasing data recorded in a hard disk. The data erasing device 1 includes a control unit 11 having a CPU (Central Processing Unit) which is a central processing unit, a memory 12, and a hard disk control unit 13.
An interface 14 for connecting the hard disk unit 2, a display unit 15, and an operation unit 16.

The control unit 11 has a memory 112 as a working area and a CPU 111. CPU11
In 1, 2 bytes is set as a predetermined unit amount, and 2 bytes of random unit data is created. The created 2-byte random unit data is stored in the memory 112. The random unit data stored in the memory 112 is supplied to the memory 12. In the memory 12, 2-byte random unit data is repeatedly and continuously recorded to form one aggregated recording data for erasing as a whole.

The control unit 11 includes a display unit 15 and an operation unit 1.
6 and 6 are connected. The display unit 15 displays the status of the data erasing device 1 and the like. For example, a display during data erasing, a power on / off display, an error display, a mode display selected by the user, an erasing operation end display, and the like are displayed.
As a configuration of these displays, a configuration of displaying on a display screen, a configuration of displaying by turning on / off the lamp, a change in the color of the lamp, or the like is used.

The operation unit 16 is composed of a power switch, a mode selection switch, an operation start switch, a reset switch and the like. The operation content selected by the operation unit 16 is supplied to the control unit 11 as an operation signal. Here, the mode selection switch sets the number of times the erasing process is performed. For example, once, three times, five times, and seven times.
The number of times of erasing processing can be selected.
The erasing process consists of creating random unit data, erasing record data, and erasing the entire area of the hard disk once. If the number of times of processing is set to multiple, the erasing process will be performed multiple times, and a new process will be performed each time. Random unit data is created in.

The memory 12 is, for example, a random access memory (RAM), and the random unit data supplied from the control unit 11 is continuously recorded to generate erase recording data. The erasing record data recorded in the memory 12 is supplied to the hard disk controller 13. The hard disk controller 13 uses the interface 1
The drive of the hard disk unit 2 connected via 4 is controlled. For example, confirmation of whether or not the hard disk unit 2 is connected, a recording start command, recording end confirmation, recording operation error recognition, erasing recording data writing, and the like. These control operations are started based on the command signal from the control unit 11. In addition, the hard disk controller 1
The signal from the hard disk unit 2 recognized in 3 is
It is supplied to the control unit 11.

The operation of the data erasing device 1 of the present invention having the above configuration will be described with reference to the flow chart shown in FIG. The connection of the hard disk unit 2 is confirmed via the hard disk controller 13 (step S101). When the connection of the hard disk unit 2 cannot be confirmed (step S101: N),
It is determined that the hard disk unit 2 is not connected, and an error display is displayed on the display unit 15 (step S
103). If the connection is confirmed (step S10)
1: Y), the capacity of the hard disk is confirmed (step S105).

Next, the mode selected by the operation unit 16 is confirmed to confirm the number of erase processes, and the selected number n is input as the value of s (step S10).
6). Two-byte random data for one unit of data is created (step S107). For example, [5]
[F] As a method of creating random data, for example, a 2-digit hexadecimal number is created based on a random number creation program, or in addition, random unit data may be created from the time of processing. For example, if the processing time is 11:05, the random unit data is [b] [5]. The random unit data and the recording data for erasing need not be random numbers as long as they are meaningless data with respect to the data already recorded on the hard disk to be erased.

Since the amount of random unit data to be created is 2 bytes, the control unit 11 can finish the random unit data creation time (processing time) in a short time. Then, the random unit data created in step S107 is stored in the internal memory 112, and the stored random unit data is written in the memory 12 (step S109). At this time, the random unit data is repeatedly supplied from the internal memory to the memory 12,
In this case, random unit data is continuously and repeatedly written, and becomes continuous data as a whole, and erase recording data as shown in FIG. 3 is configured.

As described above, by repeatedly writing the already created random unit data, it is possible to shorten the processing time for creating the erasing record data.
Specifically, firstly, the amount of data for creating random unit data (unit data amount) is 2 bytes, and since the amount of data is relatively small, the processing time for creating random unit data is significantly reduced. Shortened. Secondly, since the process of writing once created random unit data to the memory 12 is repeatedly performed, it is not necessary to execute the process of creating random unit data each time when writing to the memory 12, and thus the processing time is reduced. Can be shortened. Thirdly, since the already created random unit data is simply repeatedly written, even a large amount of erasing record data can be easily created and the processing time can be shortened.

The erasing record data created in the memory 12 is written to the hard disk of the hard disk unit 2 via the hard disk controller 13 (step S113). This data writing is performed in units of one block (512 bytes) that constitutes the recording capacity of the hard disk. The capacity of the memory 12 is preferably at least one block or more. With such a capacity, one block can be recorded by reading from the memory 12 only once, and the processing efficiency is improved. Further, it is preferable that the capacity of the memory 12 is a capacity for a plurality of blocks (512 bytes × n (n is a natural number)).

The erasing record data is written in the hard disk 21 of the hard disk unit 2 (step S11).
1). Writing to the hard disk 21 is performed for each block. In the case of the IDE method, writing is performed for each sector. It is determined whether or not the erasing record data is written in the entire area of the hard disk 21 capacity (step S113). If it is not written in the entire area (step S113: N), it is determined whether an error signal is received. (Step S115). When the error signal is received (step S115: Y), the drive of the hard disk unit 2 is stopped (step S117), and the display unit 1
An error display is output to 5 (step S119).

When no error signal is received (step S115: N), step S113 is executed again.
When the writing to the hard disk 21 is completed (step S113: Y), the variable k is incremented by 1 (step S121), and it is determined whether the variable k has reached the number of times of writing (k = s) (step S123). . If the write count has not been reached (step S123:
N), and steps S107 to S121 are executed again. If it has reached (step S123:
Y), the drive of the hard disk unit 2 is stopped (step S125), and the end display is output to the display unit 15 (step S127).

After step S123, there may be provided a step of rewriting the entire capacity by using the erase recording data as specific uniform data, for example, data in which all bits are 1 or 0. Specifically, a step of creating unit data in which 2 bytes are all 1s or 0s as random unit data, and steps S109 to S
Steps similar to steps up to 113 are performed in step S
It is provided between 123 and step S125. By performing such an erasing operation last, it is possible to physically indicate that the hard disk unit has been erased.

The step S107 constitutes a random unit data producing means, the step S109 constitutes a recording data producing means, the steps S111 and S113 constitute a medium recording means, and the step S106, step S121 and step S123 erase the medium. Processing control means is configured. Furthermore, step S
107, the first step, step S109, the second step, step S111 and step S113.
Constitutes the third step.

The storage medium erased by the data erasing apparatus 1 or the data erasing program of the present invention may be a magnetic recording medium such as a hard disk, an optical recording medium or a magneto-optical recording medium. In this case, examples of the external device connected to the interface include a MO drive, a CD-R drive, and a DVD drive. The CPU used in the control unit 11 of the present embodiment is a 16-bit CPU that creates 2-byte random unit data.
Therefore, the initial cost is low. Other than this, 32
It is also possible to use a bit CPU, and in this case, the random unit data can be 4 bytes, and the data erasing process can be performed more quickly.

Further, the program shown in the flow chart of FIG. 2 may be recorded in a computer-readable recording medium such as a flexible disk to erase the data in the hard disk incorporated in the personal computer. Good. In this case, the operation system program and the program of the present invention are recorded on the flexible disk, and when the personal computer is started, the personal computer is started by using the operation system program recorded on the flexible disk. It is also possible to adopt a configuration in which a hard disk erasing process is performed by a program.

In the above embodiment, the erasing record data is recorded in the entire area of the recording medium such as the hard disk, but the erasing record data may be recorded in a part of the recording medium. For example, at specific intervals,
A method of recording erasing record data of a specific data amount, or a method of recording erasing record data only at the position where data is recorded if the position where the data is recorded on the hard disk is known in advance. You can also Further, the position for writing the erasing record data may be randomly determined and may be written at random intervals. In this case, some of the recorded data remains, but the data is erased randomly, so that it becomes unusable as data in the end, and the same effect as deleting the data in that the data cannot be used. Is obtained.

[0029]

According to the invention described in claims 1 and 8, random unit data is created, and the erase record data is created continuously by repeating the random unit data. Therefore, the time for creating the erase record data is shortened. As a result, the processing time for erasing the data recorded on the recording medium is shortened.

According to the second aspect of the present invention, random unit data is repeatedly and continuously written in the memory to form erasing record data, and the erasing record data is read from the memory and written in the recording medium. The time for writing the erasing record data into the recording medium is shortened, and as a result, the erasing processing time for the data recorded in the recording medium is shortened.

According to the third aspect of the invention, the processing time for erasing the data recorded on the hard disk can be shortened. According to the invention described in claim 4, since the random unit data is 2 bytes, the creation time of the random unit data can be shortened. According to the invention of claim 5,
When creating the erasing record data, the burden of processing operation is small and the data creation time can be shortened.

According to the sixth aspect of the invention, all the data recorded on the recording medium can be erased. According to the invention described in claims 7 and 9, by changing the random unit data and performing the erasing process a plurality of times,
The data recorded on the recording medium can be erased more reliably.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a data erasing device of the present invention.

FIG. 2 is a schematic diagram showing a configuration of random unit data and erasing record data.

FIG. 3 is a flowchart showing the operation of the present invention.

FIG. 4 is a schematic diagram showing a state of a recording signal before erasing.

FIG. 5 is a schematic diagram showing a state of a recording signal after erasing by a conventional erasing method.

[Explanation of symbols]

1 Data erasing device 11 Control unit 111 CPU 112 memory 12 memories 13 Hard disk controller 14 Interface 15 Display 16 Operation part 2 hard disk unit 21 hard disk

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroshi Takahashi             543-9 Tsuruma, Machida, Tokyo Wa Co., Ltd.             In Lee E sea

Claims (9)

[Claims] 1. A random unit data creating means for creating a predetermined unit amount of random data, a recording data creating means for creating erase recording data based on the created random unit data, and an created erase. A data erasing device comprising a recording medium for recording recording data on a recording medium. 2. The data erasing device according to claim 1, further comprising a memory for accumulating the erasing record data, and the medium recording means records the erasing record data accumulated in the memory on a recording medium. 3. The data erasing device according to claim 1, wherein the recording medium is a hard disk. 4. The data erasing device according to claim 1, wherein the predetermined unit amount is 2 bytes. 5. The data erasing device according to claim 1, wherein the erasing record data is formed by repeating and continuing random unit data. 6. The data erasing device according to claim 1, wherein the recording data creating means records the erasing recording data on the entire area of the recording medium. 7. The random unit data creating means creates new random data, the recording data creating means creates new erasing record data, and the medium recording means creates new erasing record data. The erasing process control means for setting the number of erasing processes for the erasing process including writing to the entire area of the recording medium.
6. The data erasing device according to any one of 1 to 6. 8. A first step of creating a predetermined unit amount of random data, a second step of repeatedly connecting the created random unit data to create erase recording data, and a created erase data Third recording data to a recording medium
A data erasing program comprising steps and. 9. The data erasing program according to claim 8, wherein the first step to the third step are repeated a plurality of times.