JPH07296490A - Information storage device - Google Patents

Abstract

PURPOSE:To surely prevent mis-erasure and to effectively utilize memory capacity by enabling recording in a storage margin region by providing and erasure inhibiting means in a recording medium and combining it with a file allocation table FAT. CONSTITUTION:This device is constituted so that a switch 21 setting permission, inhibition for erasing data in a recording medium 8 is provided and a condition of the switch 21 is outputted to the outside. A prescribed recording operation is performed by a whole control section independently of a condition of the switch 21 at the time of recording image, recorded in an information unrecorded region shown in FAT of the storage device 8, while a directory is generated, and FAT is updated. At the time of erasing, propriety of erasing is discriminated according to a condition of a switch S, also, at the time of read-out of data, data can be read out independently of a condition of the switch S. Thereby, reliability for preventing mis-erasing is improved, while new information can be stored without erasing information already stored if there is a margin in storage capacity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information storage device, and more particularly to a technique for effectively utilizing the storage capacity of the information storage device while surely protecting the information already stored in the information storage device. It is a thing.

[0002]

2. Description of the Related Art Conventionally, the following two methods have been known to prevent accidental erasure in an information storage (recording) device.

1 Magnetic tape (Video cassette)
tte, Audio cassette, Digita
l Data) and floppy disk (3.5inc)
h, 5.25 inch), a case, a cassette, a jacket, etc. are provided with a claw or a slide member indicating write protection, and the state of these members is detected by the device to prohibit writing.

(2) A method of adding a deletion prohibition flag to a file in a floppy disk or a hard disk and prohibiting deletion of a file having this flag.

[0005]

In the first conventional example, erroneous erasure is prevented even when there is an unrecorded area (area where information already recorded can be recorded without destroying the recorded information) in the storage means. The nail was broken (sliding = erasure prohibited)
In that case, there is a drawback that the recording cannot be performed and the capacity of the storage means cannot be effectively used.

Further, in the second conventional example, since the information on whether or not erasure is prohibited is stored for each file in the storage means, the above problem can be avoided. Only bits were allocated, and if this bit was read incorrectly, there was a risk of accidental erasure.

The present invention seeks to solve these two problems at the same time.

[0008]

In order to achieve the above object, the first invention of the present application is to instruct permission / non-permission of erasing storage means and information stored in the storage means. And an instruction means for prohibiting deletion of the information stored in the storage means, the information is stored only in an area other than the area where the information is already stored in the storage means. And a control means for controlling the storage means to store
When the information stored in the storage device is instructed by the instructing means to be information that is not permitted to be erased, new information is recorded only in the area other than the area in which the information is already recorded. Acts like.

Further, by using the information stored in a specific area in the storage means to detect an area of the storage means in which the information has already been stored, the area in which the information has already been recorded. By determining whether or not it is possible to prevent the loss of necessary information due to an erroneous erase operation.

[0010]

EXAMPLE FIG. 1 shows an example of the present invention.

In the figure, 1 is a lens, 2 is a shutter, 3 is an image pickup device, 4 is a signal processing circuit for performing various corrections, clamps and the like on an image signal output from the image pickup device 3,
Reference numeral 5 is an A / D converter for performing analog-digital conversion of the image signal output from the signal processing circuit 4, 6 is a buffer memory unit for temporarily storing at least one image data, and 8 is image data. A removable storage medium such as a semiconductor memory for storing or reading data, 10 is a digital I / F unit for transmitting image data to an external computer or the like (not shown), and 7 is for transmitting image data. A memory control unit for controlling and controlling the buffer memory unit 6,
Reference numeral 9 denotes the image sensor 3, the A / D converter 5, and the memory control unit 7,
A timing generator for outputting various timing signals, 11
Is an overall control unit, and 12 is a RAM for storing various data in the overall control unit 11.

Further, FIG. 2 shows the details of the storage medium 8.

In the figure, 20 is a memory such as a flash memory, 21 is a switch for setting permission / non-permission of erasing data recorded in the memory 20, which is on / off.
23 is an I / F unit for transmitting / receiving data to / from the outside, 22 is a memory 20, I / F
The control unit controls the unit 23.

Here, an example in which the state of the switch 21 is output as it is to the outside and a control unit 22 of the memory is further provided in the storage medium is shown in FIG. 2 a, and the state of the switch 21 is controlled via the control unit 22. FIG. 2 shows an example in which a memory control unit is further provided in the storage medium for transmission to the outside.
An example in which the memory unit 24 including the memory 20 and the switch 21 is removable in b, and the state of the switch 21 is directly output to the outside in FIG.
0, the memory unit 24 including the switch 21 is removable, and an example of transmitting the state of the switch 21 to the outside via the control unit 22 is shown in FIG. 2d.

In any case, the same effect can be obtained in this embodiment.

A storage system of the storage medium 8 having the above structure will be described with reference to FIG.

The storage medium 8 is divided into a management area and a file area as shown in FIG.

The management area is for managing files.
Reserved area, file allocation table (hereinafter F
AT), there is a directory. Further, the actual data of the file is stored in the file area.

The access unit of the file area is called a cluster, and a file is composed of one or a plurality of clusters depending on the data size.

The FAT has an entry corresponding to each cluster, and the value of the entry corresponding to the continuing cluster is stored in each entry. If there is no continuing entry (entry corresponding to the last cluster in the file), a value indicating that is stored. The directory stores the file name, file size, entry value at the beginning of the file, date, etc.

The FAT is often redundantly stored in a plurality of locations. This is performed for the purpose of ensuring reliability because the information stored in the storage medium becomes unreadable when the FAT data becomes unreadable. Even if it is not the case, it is often the case that some measure is basically taken to secure reliability for FAT.

Since this storage method is known, a more detailed description will be omitted here.

Next, the operation at the time of photographing will be described with reference to the flowchart of FIG.

When an image recording / recording command is issued to the overall controller 11 by a switch (not shown) or the like (or, an image recording / recording command from an external computer or the like (not shown) is I / O).
When input through the F unit 10, the general control unit 11 does not depend on the state of the switch 21 (provided that the status of the free area of the storage medium is confirmed by FAT and there is an unstored area). The imaging recording operation is executed.

That is, the shutter 2 is driven to perform exposure (S
300) The image sensor 3 is read (S301).

This image signal is subjected to color correction and various kinds of processing in the signal processing circuit 4 (S302).

After this, analog-to-digital conversion is performed by the A / D converter 5 (S303) and is temporarily stored in the buffer memory unit 6 via the memory control unit 7 (S30).
4).

After that, the image data stored in the buffer memory unit 6 is stored in the file area of the storage medium 8 via the memory control unit 7 in an area where information (indicated by FAT) is not stored. (S305). Then, while creating the directory, F in the management area
The AT is updated (S306).

That is, at this time, the memory control unit 7 detects the area in which the data is already stored in the file area according to the value of FAT, and the buffer memory is stored in the area other than that (the area in which the data is already stored). The image data once stored in the unit 6 is transmitted and stored, and along with that (storage of image data), the value corresponding to the cluster connection is stored in the entry corresponding to the cluster in which the newly stored image data is stored. To do.

Next, the operation at the time of erasing will be described with reference to the flowchart of FIG.

Certain image data (single or plural, depending on the case, all data in a file area in the storage medium) by a switch or the like not shown in the overall control unit 11
Is issued (or, an erasing instruction command from an external computer or the like (not shown) is issued to the I / F unit 10).
The control unit 11 reads the state of the switch 21 (S
400).

If the deletion is permitted, the image data specified by the deletion command is deleted (S401).

That is, predetermined data that means erased is stored in the corresponding entry in the directory area and the FAT area corresponding to the designated image data file in the management area of the storage medium 8.

If erasing is not permitted, the fact that erasing is not permitted is displayed on a display device (not shown), and the erasing operation is not performed (S402). (Or, if it is an erasing instruction by an external computer (not shown), it returns an erasing non-permission command.)

The display method is arbitrary and is not limited, for example, a display indicating that it cannot be erased by a liquid crystal display in the viewfinder of the camera and a warning sound generated by a sounding member (not shown).

Next, the data stored in the storage medium 8 can be read out regardless of the state of the switch 21.

That is, when a command for reading image data is issued to the overall control unit 11 by a switch or the like (not shown) (or a read command command from an external computer or the like (not shown) is issued to the I / F unit 10). The overall control unit 11 reads the file name of the instructed image data, the directory of the storage medium 8 obtained via the memory control unit 7 and the FAT information, and specifies the designated image data. , And transmits the desired image data to the buffer memory unit 6 via the memory control unit 7. After that, the data is again output to an external computer or the like (not shown) via the memory control unit 7 and the I / F unit 10.

When the instruction of the erase prohibition instructing means 21 is transmitted to the memory control section 7 via the control section 22 as shown in FIGS. 2b and 2d, the erase prohibition instructing means 2 is set as described above.
In addition to the case where the instruction 1 is transmitted as it is, the control unit 22 may interpret the control command from the memory control unit 7 to control the memory 20.

In the present embodiment, the overall control unit 11 and the memory control unit 7 are described as separate blocks, but the two can be contained in a single chip to simplify and reduce the system configuration. Needless to say.

(Second Embodiment) FIG. 6 shows another embodiment.

In the figure, the same numbers as those in the first embodiment are given the same numbers, and the details of the operation of each block are omitted.

In the figure, reference numeral 24 is a removable memory unit including the memory 20 and the switch 21, as shown in FIGS. 2c and 2d, and 22 is a control unit for controlling the memory 20.

In this embodiment, only the memory unit 24 shown in FIGS. 2c and 2d can be directly attached to and detached from the camera without passing through the control unit 22 and the I / F unit.
Further, the overall control unit 11 can detect the state of the switch 21 on the memory unit 24 via the control unit 22.

Further, in the present embodiment, the overall control unit 11 and the memory control unit 7 and the control unit 22 are represented as separate blocks for convenience of description, but it goes without saying that they may be configured by a single chip. Is.

The recording method of the memory unit 24 having the above structure will be described with reference to FIG.

The memory 20 in the memory unit 24 is shown in FIG.
It is divided into a management area and a file area.

The management area is for managing files.
Reserved area, file allocation table (hereinafter F
AT), there is a directory. Further, the actual data of the file is stored in the file area.

The access unit of the file area is called a cluster, and a file is composed of one or a plurality of clusters depending on the data size.

The FAT has an entry corresponding to each cluster, and the value of the entry corresponding to the continuing cluster is stored in each entry. When there is no continuing entry (entry corresponding to the last cluster in the file), data indicating that is stored. The root directory stores the file name, file size, the value of the entry at the beginning of the file, the date, etc.

Further, the FAT is often redundantly stored in a plurality of places. This is done for the purpose of ensuring reliability because the information stored in the storage medium becomes unreadable when the FAT data becomes unreadable. Even if it is not the case, it is often the case that some measure is basically taken to secure reliability for FAT.

Since this storage method is known, a more detailed description will be omitted here.

Next, the operation at the time of photographing will be described with reference to the flowchart of FIG.

When an image pickup / recording command is issued to the overall control unit 11 by a switch or the like (not shown) (or, an image pickup / recording command command from an external computer or the like (not shown) is I / O).
When input via the F unit 10, the general control unit 11 does not depend on the state of the switch 21 on the recording medium 24 (however, the status of the free space of the storage medium is FAT).
If there is an area that has not been stored,
The imaging recording operation is executed.

That is, the shutter 2 is driven to perform exposure (S300) and the image pickup device 3 is read (S30).
1).

This image signal is subjected to color correction and various kinds of processing in the signal processing circuit 4 (S302). After this, analog-digital conversion is performed by the A / D converter 5 (S3
03) It is stored in the memory unit 6 via the memory control unit 7 (S304). After that, the image data stored in the memory unit 6 is stored in the file area of the memory unit 24 via the memory control unit 7 and the control unit 22 in an area where information (indicated by FAT) is not stored. (S305). Then, the directory is generated and the FAT in the management area is updated (S306).

That is, at this time, the overall control unit 7 detects the area of the file area in which the data is already stored according to the value of FAT, and stores the buffer memory in an area other than that area (the area in which the data is already stored). The image data once stored in the unit 6 is transmitted and stored, and along with that (storage of image data), the value corresponding to the cluster connection is stored in the entry corresponding to the cluster in which the newly stored image data is stored. To do.

Next, the operation at the time of erasing will be described with reference to the flowchart of FIG.

When a command for erasing predetermined image data is issued to the overall control unit 11 by a switch or the like (not shown) (or an erasing command command from an external computer or the like, not shown, is transmitted via the I / F unit 10. Then, the overall control unit 11 reads the state of the switch 21 on the memory unit 24 via the control unit 22 (S400).

When the deletion is permitted, predetermined image data is deleted (S401). That is, the predetermined data that means erased is stored in the directory corresponding to the predetermined image data file in the management area of the memory unit 24 and the corresponding entry in the FAT area.

If erasing is not permitted, the fact that erasing is not permitted is displayed on a display device (not shown), and the erasing operation is not performed (S402). (Or, in the case of an erasing command from an external computer (not shown), the erasing non-permission command is returned.) The display method is, for example, a display indicating that the liquid crystal display in the viewfinder of the camera cannot erase or The generation of a warning sound by the sounding member is arbitrary and is not limited.

Next, when reading the data recorded in the memory unit 24, the data can be read regardless of the state of the switch 21 on the memory unit 24.

That is, when a command for reading out predetermined image data is issued to the overall control section 11 by a switch or the like (not shown) (or a read command command from an external computer or the like (not shown) causes an I / F. The data recorded in the memory unit 24 is input to the control unit 22,
It is stored in the memory unit 6 via the memory control unit 7.
After that, the data is again output to an external computer or the like (not shown) via the memory control unit 7 and the I / F unit 10.

Although it has been explained here that the overall control unit 11 reads the instruction information of the erase permission / non-permission instruction means from the memory unit 24 by the control unit 2, the erase permission / non-permission in the memory unit is explained. Of course, the overall control unit 11 may directly read the instruction information of the instruction means.

(Third Embodiment) In addition to this, when information is stored in the storage medium 24 by the camera of the second embodiment and read by a computer having the control unit configuration as in the first embodiment, the information shown in FIG. Similarly, it is possible to use an adapter including the control unit 22 and the I / F unit 23.

In the case of such a system, in a portable device such as a camera, the control unit 22 can be downsized by combining the memory control unit 7 and the overall control unit 11 into a single chip. In general-purpose equipment, the I / F part with the external storage medium has a high commonality, for example, P
Since it is preferable that the CMCIA or the like is used, the memory unit 24 is connected to a common I / F through an adapter having a control unit and an I / F unit as shown in FIGS. 2c and 2d.
If it is handled as the storage medium of FIG. 2a and FIG. 2b having a section, there is an effect that it is not necessary to increase the types of ports on the computer side.

In both the first and second embodiments, the data captured by the image pickup device is processed and then A / D converted. However, the output of the image pickup device is used as it is (of course about the CDS). Needless to say, the processing may be performed after digital-to-D conversion and digital processing. By doing so, it becomes possible to form the signal processing and memory control unit 7 in a single chip.

[0067]

As described above, according to the present invention,
Even if an instruction is made to prohibit erasing in order to protect the information, new information can be stored without destroying the already stored information while there is room to store the information. It is possible to obtain highly reliable erroneous erasure prevention means by combining the erroneous erasure prohibition instruction means outside the memory and the FAT value, as compared with erroneous erasure prevention by a single erasure inhibition bit (flag).

[Brief description of drawings]

FIG. 1 is a configuration block diagram of an embodiment of the invention.

FIG. 2 is a configuration block diagram of a recording medium according to an embodiment of the invention.

FIG. 3 is a flowchart of a photographing operation according to the embodiment.

FIG. 4 is a flowchart when erasing the recording medium of the embodiment.

FIG. 5 is a data area diagram of the recording medium of the embodiment.

FIG. 6 is a configuration block diagram of another embodiment.

Claims (2)

[Claims] 1. A storage unit, an instruction unit for instructing permission / non-permission of erasing the information stored in the storage unit, and a prohibition of erasing the information stored in the storage unit by the instruction unit. Information storage comprising: a control means for controlling the storage means so that the information is stored only in an area of the storage means other than the area where the information is already stored when instructed. apparatus. 2. The information stored in a specific area of the storage means is used to identify an area of the storage means in which information is already stored.
The information storage device described in 1.