JPH04167038A - Write protection device for storage device - Google Patents

Abstract

PURPOSE:To inhibit or allow writing operation on a storage medium from outside by providing a write protecting means which stops the output of a write control signal or resets the stop state by operation from outside the storage device and a means which displays the stop state. CONSTITUTION:This device is equipped with a control means 13 which outputs the data write control signal to storage devices 14 and 15, the write protecting means 13 which stops the output of the write control signal or resets the output stop state of the write control signal by the operation from the outside 11a of the storage devices 14 and 15, and the display means 12 which displays the output stop state set by this write protecting means 13. Consequently, even when a storage medium is not provided with a means for inhibiting or allowing its writing operation, a write protecting function is securely realized and whether the writing operation is inhibited or allowed is visually confirmed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Field of Industrial Application)] The present invention particularly relates to a write protection device for an external storage device such as a floppy disk device or a hard disk device.

(Prior Art) Conventionally, a computer system such as a personal computer is provided with an external storage device such as a floppy disk device (FDD). In such external storage devices, in order to protect data recorded on the storage medium, the storage medium is provided with a write protection function that prohibits data writing operations.

Specifically, the jacket (case) that stores the disc.
A notch (cutout tag) is provided to indicate whether or not the write protection status is enabled.

The FDD is provided with a write protect detection switch that detects the notch, and when a disk is inserted into the FDD, the write protect state is detected by the write protect detection switch.

Further, in the case of a cassette type magnetic tape, a small window for writing permission is provided in the housing, and the state of write protection is identified according to the open/closed state of this small window. Furthermore, in the case of a memory card, a write protection switch is provided, and writing operation is prohibited or permitted depending on the setting state of the switch.

(Problems to be Solved by the Invention) A write protection function for each storage medium can be realized by using a conventional notch for an FDD, a small window for a cassette-type magnetic tape, and a switch for a memory card. However, the above-mentioned method cannot be applied to a hard disk device that drives a fixed storage medium. Also, F
In a DD or the like, when a storage medium is installed inside the drive, it is not possible to visually confirm whether the write operation is prohibited or permitted. Furthermore, if the writing operation is set to a prohibited or permitted state and the storage medium is installed inside the drive, the prohibited or permitted state cannot be changed.

An object of the present invention is to provide a storage device in which the prohibition or permission state of write operations on a storage medium can be externally set or changed and visually confirmed without providing any special means to the storage medium. The purpose of the present invention is to provide a write protection device.

[Structure of the Invention] (Means and Effects for Solving the Problems) The present invention provides a control means for outputting a write control signal instructing a data write operation to a storage device, This write protection device includes write protection means for stopping the output of a write control signal to the device or canceling the state in which the output of the write control signal is stopped, and display means for displaying the state in which the output of the write control signal is stopped by the write protection means.

With such a configuration, even if the storage medium is not provided with a means for setting a write operation prohibition or permission state, the write protection function can be reliably realized and changed. Furthermore, by displaying the output stop state of the write control signal, it is possible to visually confirm whether the write operation is prohibited or permitted.

(Example) The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram showing the main parts of a system according to the same embodiment. The main control unit 10 is, for example, a central processing unit (CPU) of a personal computer, and controls the entire system and performs various data processing. The input unit 11 consists of a keyboard, and has various input keys for data input.

The input unit 11 has a write protection function setting key (SW) lla according to the present invention. The display unit 12 displays a write operation prohibition state or permission state according to the present invention.

The input/output control unit 13 is controlled by the main control unit 10 to
It controls the input section 11 and the display section 12, and also controls the input and output of a floppy disk device (FDD) 14 and a hard disk device (HDD) 15, which are external storage devices. The input/output control unit 13 is comprised of BIO5 (Basic Output System), which is a part of O8 of the personal computer.

The FDD 14 is capable of replacing a disk 14a which is a storage medium, and has a switch 1 for detecting a write protection notch 14b provided on the disk 14a.
It is equipped with 4c. The HDD 15 is a device that writes/writes data to a disk t5a fixed to a rotating mechanism, and does not have its own write protection function.

Specifically, this system is, for example, a personal computer equipped with a keyboard 11 and a display f20, as shown in FIG.

A display section 12 according to the present invention is included in a part of this computer.
is provided. As shown in FIG. 3, the display section I2 consists of a pair of lamp indicators 24 and 25, one of which is connected to the FD.
One is an indicator 24 for write protection (write inhibited state) of the HDD 14, and the other is an indicator 25 for write protection of the HDD 15.

Next, the operation of this embodiment will be explained.

The input/output control unit 13 is controlled by the main control unit 10 to
It exchanges various interface signals with the FDD 14 or HDD 15, and outputs write data and a write gate signal in the write mode.

If the disk 14a is attached to the FDD 14, a write operation is executed by a write gate signal from the human output control section 13, and data corresponding to the write data is recorded on the disk i4a.

In HD D 15, disk 1 fixed to the rotating mechanism
A write operation is executed for 5H by a write gate signal from the input/output control unit 13, and data corresponding to the write data is recorded.

Here, when the write protection function setting key 11a provided on the keyboard 11 is turned on, the input/output control unit 1
3 stops the output of the write gate signal and maintains the output stopped state. This allows F D D 14 or H
Since the output of the write gate signal to D D 15 is stopped, the write operation is prohibited. Therefore, a situation in which new data overwrites old data on the disk 14a or disk 15a is prevented. When the setting key 11a is turned off, the input/output control unit 13 releases the output stop state of the write gate signal.

The input/output control section 13 outputs a signal to the display section 12 indicating that the FDD I4 or the HDD 15 is in a write-protected state in response to the ON operation of the setting user key 11a. That is, as shown in FIG. 3, F D D 1
4 is set to a write-protected state, the display 24
is displayed, and in the case of HDD 15, the other display 25 is displayed. Therefore, depending on the display state of the display unit 12, it is possible to visually confirm whether either the FDD 14 or the HDD 15 is set to the write-protected state.

FIG. 4 is a diagram showing the appearance of a measuring device to which the present invention is applied. The measuring device includes an input section 11 consisting of a keyboard and a display device 32 for displaying measurement results, etc.
is provided. Furthermore, the measuring device is provided with a write protection function setting switch 30 having a display function. As shown in FIG. 5, this setting switch 30 is composed of a slide switch, and sets a write permission state or a write protection (write prohibition) state depending on the position of the slide member 30a. Further, the setting switch 30 is
A display 30b is incorporated in the slide member 30a, and the display 30b is configured to light up when the slide member 30a is moved to a write-protected position.

The measuring device includes a memory card 31 as a storage medium, for example.
is used. When the setting switch 30 is slid to the write protection position, the input/output control section 13 shown in FIG.
A circuit corresponding to the above sets the write-inhibited state to the memory card 31. As a result, data writing operations to the memory card 31 are prohibited, so data that has already been recorded is protected. Further, when the write-inhibited state is set, the display 30b built into the slide member 30a displays the information, so that it can be visually confirmed that the write-inhibited state for the memory card 31 has been set.

FIG. 6 is a diagram showing a modification of the input/output control section 13 shown in FIG. 1. That is, FIG. 6 shows the BrO3 shown in FIG.
In contrast to the so-called software-based embodiment, this embodiment is based on 11-ware using a logic circuit.

The input/output control unit 13 includes a first AND circuit 40 and a second
A logic circuit having an AND circuit 41 is provided.

The first AND circuit 40 receives the write gate signal WGI from the disk controller (FDC) 42 of the FDD 14, and is used for setting the write protection function.
The gate is controlled by the write protect signal WP from a to control the transfer of the write gate signal WGI. On the other hand, the second AND circuit 41 receives the write gate signal W from the disk controller (HDC) 43 of the HDD 15.
G2 is input, and the gate is controlled by the write protect signal WP from the write protection function setting key 11a to control the transfer of the write gate signal WG2.

When the setting key 11a is turned on, the logic level “L”
”, the write protect signal WP of the first AND circuit 40
and is output to each first input terminal of the second AND circuit 41. Therefore, the first AND circuit 40
Write gate signal W from 42 to FDD I4
Prohibit transfer of GI. As a result, F D D 14
is in a write operation or prohibited state.

Further, the second AND circuit 41 connects the HD C43 to the HD
Transfer of write gate signal WG2 to D15 is prohibited. As a result, the HDD 15 enters a state in which write operations are prohibited. When the setting key 11a is turned off, the transfer inhibited state of the write gate signals WGI and WG2 is canceled, and the write inhibited state is canceled.

[Effects of the Invention] As described in detail above, according to the present invention, it is possible to set a state in which write operations are prohibited on a storage medium by an external operation without providing a write protection means for prohibiting write operations on the storage medium. , and can also cancel the prohibited state. Therefore, it is possible to easily set write protection on the storage medium or change the write permission state from the outside. Furthermore, by displaying a set of write operation prohibition states on the display means, the write protection state can be visually confirmed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram according to an embodiment of the present invention, FIG. 2 is a perspective view showing the external appearance of a personal computer according to the embodiment, FIG. 3 is a partially enlarged view of FIG. 2, and FIG. 4 is the same. FIG. 5 is a partially enlarged view of FIG. 4, and FIG. 6 is a block diagram showing a modification of the input/output control unit according to the embodiment. 10... Main control section, 11... Input section, lla.
... Key for setting the write protection function - 112 ... Display section, 14 ... Floppy disk device, 15 ... Hard disk device. Applicant's Representative Patent Attorney Takehiko Suzue Figure 1 Figure 2 Figure 5 Figure 4 Figure 6

Claims (1)

[Scope of Claims] A control means for outputting a write control signal instructing a data write operation to a storage device; and a control means for outputting a write control signal from the control means to the storage device by an operation from outside the storage device. A write protection device for a storage device, comprising write protection means for stopping the output of the write control signal or canceling the output stop state of the write control signal, and display means for displaying the output stop state of the write protection means.