JP2006146467A - Recording medium and storage area changing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recording medium which has a storage means which is divided into a plurality of storage areas and automatically switches a storage area when the remainder of an active area becomes small so as to use a large-capacity recording medium in a conventional recording-and-reproducing device. <P>SOLUTION: A readable and writable recording medium 100, which is connected to an external recording-and-reproducing device to use, is provided with; a storage means 160 having a plurality of storage areas; a controller 120 which controls the storage means 160 based on instructions from the recording-and-reproducing device; an active area designation register 140 which designates an active area from the plurality of storage areas; and an active area changing means 150 which switches an active area if the remainder of the active area is at a preliminarily fixed threshold value or less. By this, the recording medium can control the switching of the storage areas. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a recording medium capable of switching storage areas and a storage area switching method.

  A recording / playback apparatus such as a digital camera or a mobile phone uses a memory card using a flash memory represented by a CompactFlash (registered trademark) or SD (Secure Digital) card as a recording medium. In recent years, with the progress of semiconductor technology and mounting technology, the capacity of a memory card is about to exceed 2 gigabytes (hereinafter referred to as GB). There has also been proposed a device that virtually shows a magnetic disk device having a capacity of several tens GB as a memory card (see, for example, Patent Document 1).

  On the other hand, many conventional recording / playback apparatuses manage still image files, moving image files, and the like in a recording medium using FAT16 (File Allocation Table 16) which is a typical file system. However, the FAT 16 is a file system whose address for managing a cluster is 16 bits. If the cluster size is 32 kilobytes (hereinafter referred to as KB), the capacity that can be managed by the FAT16 file system is only 2 GB at maximum. Therefore, in a conventional FAT16 recording / reproducing apparatus, when a recording medium having a capacity exceeding 2 GB is used, there is a problem that an area exceeding 2 GB cannot be easily handled.

In response to this problem, the conventional memory card and storage area switching method can select one of a plurality of storage areas by providing a mechanical switch in a memory card having a plurality of storage areas within 2 GB. (For example, refer to Patent Document 2).
JP 2004-213487 A JP 2004-86503 A

  In the conventional configuration, a new mechanical switch has to be added to select one from a plurality of storage areas.

  However, the shape of the memory card is determined by the standard. For example, in the case of an SD card, the external dimensions are 24.0 mm (W) × 32.0 mm (L) × 2.1 mm (T) according to the SD memory card standard, and the position of the write protect switch is also determined. Yes. In order to add a new mechanical switch, there is a problem that a new standard has to be formulated.

  In addition, in order to change the shape of the memory card, it is necessary to change the mold for producing the memory card, so that there is a problem that the manufacturing cost becomes expensive.

  The present invention solves the above-mentioned conventional problems, and provides a recording medium and a storage area switching method capable of selecting one of a plurality of storage areas without changing the shape defined by the standard. The purpose is to provide.

  In order to solve the above-described conventional problems, the recording medium of the present invention is a readable / writable recording medium used by connecting to an external recording / reproducing apparatus, an interface connected to the recording / reproducing apparatus, and a plurality of storage areas A storage unit having a characteristic value unique to the recording medium, a controller for controlling the storage unit based on an instruction from the recording / reproducing apparatus or the value of the internal register, and a plurality of storage areas An active area designation register for designating one area of the active area as an active area, and an active area switching means for instructing the active area designation register to switch the active area and for causing the recording / reproducing apparatus to recognize the new active area. The active area switching means comprises the active area. It is characterized in that to determine whether to switch the active region based on the remaining storage capacity.

  Further, in the recording medium, the active area switching unit compares the remaining amount with a predetermined threshold value by comparing a remaining amount calculating unit that receives a file system from the controller and calculates the remaining amount of the active area, and compares the remaining amount of the active area. An active region switching determination unit that determines switching; an active region designation register updating unit that updates a value of the active region designation register when the active region switching determination unit determines to switch the active region; and the interface And a card insertion / removal control means for generating a card insertion / removal signal and detecting that the recording / reproducing apparatus has inserted / removed the card.

  Further, in the recording medium, the controller replaces a part of the internal register based on the calculation result of the active area capacity calculating means and the active area capacity calculating means for calculating the capacity of the active area from the active area designation register. And internal register conversion means.

  Further, in the recording medium, the controller includes an offset calculating unit that calculates an offset of the address from the active area designation register, and an adder that adds the calculation result of the offset calculating unit and the address transmitted from the recording / reproducing apparatus. It is characterized by including.

  Further, in the recording medium, the controller includes means for storing a file system that is read and written by the recording / reproducing apparatus.

  Further, the recording medium further comprises display means for recognizing the storage area designated by the active area designation register from the outside.

  Further, the recording medium further comprises display means for recognizing from the outside that the storage area designated by the active area designation register has been switched.

  Furthermore, in the storage area switching method of the present invention, it is possible to read and write by connecting to an external recording / reproducing apparatus, an interface connected to the recording / reproducing apparatus, a storage means having a plurality of storage areas, and a recording medium specific An internal register that holds the characteristic value of the controller, a controller that controls the storage means based on an instruction of the recording / reproducing apparatus and a value of the internal register, and an active area designation that designates an active area from the plurality of storage areas In a storage area switching method of a recording medium comprising a register and an active area switching means for switching the active area based on a remaining amount of the active area, a step of reading a file system of the active area, and based on the file system Calculating a remaining amount of the active area; Comparing the remaining amount with a predetermined threshold to determine switching of the active region, updating a value of the active region designation register when the determination of switching the active region is made, and the active When it is determined to switch the area, the interface is controlled to generate a card insertion / removal in a pseudo manner so that the recording / reproducing apparatus detects the card insertion / removal.

  According to the recording medium and the storage area switching method of the present invention, one of a plurality of storage areas in the recording medium can be selected without changing the shape defined by the standard.

  Embodiments of a recording medium and a storage area switching method of the present invention will be described below in detail with reference to the drawings.

  FIG. 1 shows a block diagram of a recording medium in the first embodiment of the present invention. In FIG. 1, the recording medium 100 is assumed to be an SD memory card. Reference numeral 110 denotes an interface for exchanging signals with a recording / reproducing apparatus (not shown), 130 denotes an internal register for storing unique information of the recording medium 100, and 160 denotes storage means having a plurality of storage areas. A controller 120 controls the communication protocol with the recording / reproducing apparatus and accesses the internal register 130 and the storage unit 160 in accordance with the SD memory card standard. Reference numeral 140 denotes an active area designation register that designates an active area from among a plurality of storage areas, and reference numeral 150 denotes active area switching means for switching the active area based on the remaining amount of the active area.

  In the SD memory card, the interface 110 includes a plurality of terminals and an interface driver 200 as shown in FIG. FIG. 2 is a diagram showing details of the interface 110 in the first embodiment of the present invention. There are a total of nine terminals, which are connected to an external recording / reproducing apparatus (not shown). The recording medium 100 is supplied with power from the recording / reproducing apparatus through the terminal VDD, the terminal VSS1, and the terminal VSS2. Further, the terminal CMD (command or response) synchronized with the terminal CLK (clock signal) and the terminal DAT0, the terminal DAT1, the terminal DAT2, and the terminal DAT3 (data) are transmitted and received. The interface driver 200 fetches commands and data from the terminals and outputs responses and data to the terminals according to the SD memory card standard. The terminal CD also used as the terminal DAT3 is used for detecting whether or not the card is connected to the recording / reproducing apparatus.

  The internal register 130 includes a plurality of registers according to the SD memory card standard. Each register is read by a command from the recording / reproducing apparatus, and affects the operation of the recording / reproducing apparatus. For example, the operating power supply voltage of the card, each specification value of the card, and the like are recorded. There is also a register in which the maximum number of bytes in the active area described later is recorded, and the recording / reproducing apparatus recognizes this value as the storage capacity of the card.

  The storage means 160 is composed of one or more storage areas. FIG. 3 is a diagram showing the configuration of the storage means 160 in the first embodiment of the present invention. FIG. 3 shows an example in which the storage unit 160 having a capacity of 8 GB is configured by four storage areas (first storage area 161 to fourth storage area 164) having a capacity of 2 GB. FIG. 3 shows an example in which the first storage area 161 is formatted in the FAT16 file system. In the FAT16 file system, a master boot record / partition table, a partition boot sector, a file allocation table 1, a file allocation table 2, and a root directory are written to create a data area. The storage means 160 can read data by designating an address from an external storage / reproduction device, and can write data by designating the address and data.

  The active area designation register 140 designates an active area from among a plurality of storage areas. The active area is an area recognized by the recording / reproducing apparatus. The active area designation register 140 is a set of 1-bit flags expressing whether each storage area is active. The flag corresponding to each storage area means that the storage area is an active area when it is 1, and means that the storage area is inactive when it is 0. Since this flag exists for the number of bits corresponding to the number of storage areas, the number of bits of the active area designation register 140 also becomes the number of bits corresponding to the number of storage areas. For example, when the storage unit 160 is composed of four storage areas as shown in FIG. 3, the active area designation register 140 is a 4-bit register.

  FIG. 4 is a diagram showing storage area switching and the value of the active area designation register 140 in the first embodiment of the present invention. In FIG. 4, the storage area drawn with a dotted line indicates an inactive area.

  FIG. 4A shows a state in which the first storage area 161 is active. At this time, the value of the active area designation register 140 is 0001b (hereinafter, the last b represents a binary number). is there. That is, bit 0 (the least significant bit is bit 0) of the active area designation register 140 corresponding to the first storage area 161 is 1.

  Similarly, FIG. 4B shows the second storage area 162, FIG. 4C shows the third storage area 163, and FIG. 4D shows the fourth storage area 164 active. The values of the designation register 140 are 0010b, 0100b, and 1000b, respectively.

  FIG. 4E shows that the value of the active area designation register 140 is 1111b and all the storage areas are active areas. In this case, the entire storage unit 160 is recognized by the recording / reproducing apparatus as one storage area. When the recording / reproducing apparatus can use a file system corresponding to a large capacity (for example, FAT32 file system instead of FAT16 file system), the recording / reproducing apparatus can access the recording medium 100 as an 8 GB large capacity SD memory card. Note that this function (a function of using the entire storage unit 160 as one storage area) is an option and may not be implemented.

  The active area switching means 150 switches the active area based on the remaining amount of the active area and generates a card insertion / removal in a pseudo manner. FIG. 5 shows a block diagram of the active area switching means 150 in the first embodiment of the present invention. As shown in FIG. 5, the active area switching unit 150 includes a remaining amount calculation unit 630, an active area switching determination unit 660, an active area designation register update unit 680, and a pseudo insertion / extraction unit 700.

  The remaining amount calculation unit 630 reads the file allocation table from the file system accumulated by the controller 120 (details of the operation of the controller 120 accumulating the file system will be described later). As described with reference to FIG. 3, the file system includes a master boot record / partition table, a partition boot sector, a file allocation table 1, a file allocation table 2, a root directory, and a data area. The remaining amount calculation unit 630 reads the partition type information stored in the partition table from the controller 120 and identifies the type of the file system. If the file system is unknown, no further processing is performed. If the file system is a known file system, the head addresses at which the file allocation table 1 and the file allocation table 2 are stored are read out. In the file allocation table, the same contents are stored in the area of the file allocation table 1 and the area of the file allocation table 2. This is because the file allocation table is important data for maintaining the connection of files, and the contents are duplicated. The remaining amount calculation unit 630 reads the file allocation table 1 or the file allocation table 2 as the FAT 620.

  Further, the remaining amount calculating unit 630 calculates the remaining amount of the active area based on the FAT 620. The FAT 620 stores information on the state of each cluster, that is, whether the corresponding cluster is in use or unused, and which cluster to connect to if it is in use. Here, the cluster is an area having a plurality of consecutive sectors (one sector is 512 bytes) as one unit. In the FAT16 file system, 32 KB is selected as the cluster size. The remaining amount calculation means 630 reads information indicating whether the cluster is in use or not used from the FAT 620, counts the number of unused clusters, and outputs it as the remaining amount 640 of the active area.

  The active region switching determination unit 660 compares the remaining amount 640 calculated by the remaining amount calculation unit 630 with a predetermined switching remaining amount 650, determines whether or not there is active region switching, and determines an active region switching control signal 670. Is output. That is, when the active area remaining amount 640 is larger than the switching remaining amount 650, it is determined that there is no switching of the active region, the active region switching control signal 670 is set to 0, and the active region remaining amount 640 is larger than the switching remaining amount 650. If it is smaller, it is determined that the active area has been switched, and the active area switching control signal 670 is set to 1 and then returned to 0. By setting the active area switching control signal 670 to 1, the active area designation register updating means 680 updates the value of the active area designation register 140, or the pseudo insertion / removal means 700 controls the interface 110 to artificially insert / remove the card. Is generated. Note that the initial value of the active region switching control signal 670 (the value when the power is turned on) is zero.

  The active area designation register updating unit 680 obtains a value REG 690 to be set in the active area designation register 140 in accordance with the active area switching control signal 670. That is, when the value of the active region switching control signal 670 is 0, the current value of the REG 690 is held, and when the value is 1, the value of the REG 690 is updated according to the detailed flow of the active region designation register update unit 680 shown below.

  FIG. 7 is a diagram showing a first detailed flow of the active area designation register updating means 680 in the first embodiment of the present invention. First, step 740 is executed in which the value REG of the current active area designation register 140 is shifted to the left by 1 bit and stored in REG. Next, step 750 in which the logical product of the REG and 1111b is stored in REG is executed. Here, 1111b logically ANDed with REG is an example in the case where the storage unit 160 is composed of four storage areas as shown in FIG. 4, and is determined by the number of bits corresponding to the number of storage areas. In step 760 in which it is determined whether or not REG as a result of step 750 is 0. If REG is other than 0, the entire process is terminated. That is, it is the case of (a) → (b), (b) → (c), (c) → (d) in FIG. 4, and the REG values are 0001b → 0010b, 0010b → 0100b, 0100b → 1000b. This is the case when it changes. In step 760, if REG is 0, step 770 is executed in which REG is set to 0001b, and the entire process is terminated. That is, it is the case of (d) → (a) in FIG. 4, and the value of REG changes from 1000b → 0001b. The switching of the active area shown in FIG. 7 shows a flow in the case where the option in which the value of the active area specifying register 140 is 1111b, that is, the option in which all the storage areas are active areas is not implemented.

  FIG. 8 is a diagram showing a second detailed flow of the active area designation register updating means 680 in the first embodiment of the present invention. FIG. 8 is a flow for implementing the option. First, step 780 is executed to determine whether the value of REG is 1111b. If REG is 1111b, step 770 in which REG is set to 0001b is executed, and the entire process is terminated. That is, it is the case of (e) → (a) in FIG. 4, and the value of REG changes from 1111b → 0001b. If REG is other than 1111b, Step 740 and Step 750 are executed, as in FIG. 7, where REG is shifted left by 1 bit, ANDed with 1111b, and stored in REG. Then, in step 760 for determining whether or not REG as a result of step 750 is 0, if REG is other than 0, the entire process is terminated. In step 760, when REG is 0, step 790 which sets REG to 1111b is executed, and the whole processing is ended. That is, it is the case of (d) → (e) in FIG. 4, and the value of REG changes from 1000b → 1111b.

  As described above, the active area switching unit 150 calculates the value of REG 690 and rewrites the value of the active area designation register 140. Note that the value of the active area designation register 140 in the initial state (at the time of factory shipment) is 0001b.

  The pseudo insertion / extraction means 700 controls the interface 110 in accordance with the active area switching control signal 670 to control the card insertion / removal in a pseudo manner. That is, when the value of the active area switching control signal 670 is 1, a card removal state is generated in a pseudo manner, and when the value is 0, a card insertion state is generated in a pseudo manner. FIG. 6 is a block diagram of the pseudo insertion / extraction means 700 in the first embodiment of the present invention and a diagram showing the connection with the recording / reproducing apparatus. In FIG. 6, the switch 500 of the pseudo insertion / extraction means 700 connects a signal from the VDD 520 via the resistor 510 having the resistance value R1 and the card detection signal 710, and is controlled by the active area switching control signal 670. The switch 500 is a switch that is turned on when the active area switching control signal 670 is 0, and is turned off when the signal is 1. The card detection signal 710 is connected to the terminal CD in FIG. 2 and is output as the DET signal 530 of the recording / reproducing apparatus. The DET signal 530 is connected to the VSS 540 via a resistor 550 having a resistance value R2. That is, the DET signal 530 is pulled down, and is 0 when the active area switching control signal 670 is 1 and 1 when 0. The recording / reproducing apparatus can recognize the card insertion / removal state by monitoring the DET signal 530. The resistance value R2 has a sufficiently large value compared to the resistance value R1.

  As described above, the active area switching unit 150 generates the active area switching control signal 670 based on the remaining amount of the active area, switches the active area, and artificially inserts / removes the card.

  The controller 120 is means for communicating with the recording / reproducing apparatus in accordance with the SD memory card standard. FIG. 9 shows a block diagram of the controller 120 in the first embodiment of the present invention. The controller 120 interprets the command 800 and data 820 received from the recording / reproducing apparatus via the interface 110 by the command decoder 830 and transmits a response 810 and data 820 to the recording / reproducing apparatus via the interface 110. Based on the command 800, the controller 120 writes the data 820 from the recording / reproducing apparatus in the storage unit 160 and reads the data 820 to the recording / reproducing apparatus. Further, the value of the internal register 130 is read as data 820 to the recording / reproducing apparatus.

  In the following, three operations different from the SD memory card standard in the controller 120 will be described. The first operation is an operation of adding an offset to the address to the storage means 160 according to the value of the active area designation register 140. The second operation is an operation of accumulating a file system that the recording / reproducing apparatus reads from the storage unit 160 and writes to the storage unit 160. The third operation is an operation for converting the data read from the internal register 130 according to the value of the active area designation register 140.

  In the first operation, the recording / reproducing apparatus accesses (reads or writes) the storage unit 160. The command 800 and data 820 are input from the interface 110 to the command decoder 830. When the command 800 is an access to the storage unit 160, the command decoder 830 operates the address acquisition unit 860 to acquire the data 820 as the logical address 870. Further, the offset calculation means 840 is operated to calculate the offset 850 based on the active area designation register 140 (details of the calculation method will be described later). Further, the logical address 870 and the offset 850 are added together by an adder 880 to be converted into a physical address 890. The controller 120 reads data 820 from the storage unit 160 and writes data 820 by the physical address 890.

  The offset 850 is calculated based on the active area designation register 140 so that the head address of the current active area becomes the logical address 0. That is, among the bits having the value of the active area designation register 140 of 1, the lowest bit is bit N (the least significant bit is 0), and the number of blocks in each storage area is B, N × B. Can be calculated. However, the block number B is determined in advance depending on the capacity of each storage area and the number of bytes for each cluster. For example, if each storage area is 2 GB and the number of sectors per cluster is 32 KB, B = 2 GB / 32 KB = 65536. At this time, if the value of the active area designation register 140 is 0100b, the offset 850 is 2 × 65536 = 0x20000 (hexadecimal number).

  In the second operation, the recording / reproducing apparatus accesses the storage unit 160 as in the first operation. The file system buffer 610 monitors the physical address 890 and data 820 generated by the access of the recording / reproducing apparatus, and accumulates the file system of the active area. That is, the file system data read from the storage unit 160 and the file system data written to the storage unit 160 are stored in the buffer, and the same data as the file system of the active area is held. Whether the data is file system data can be identified by whether the value of the physical address 890 is the first sector of the active area. The file system stored in the file system buffer 610 is used by the active area switching means 150 to calculate the remaining active area. In the present embodiment, the method of monitoring the access of the recording / reproducing apparatus and accumulating the file system has been described. However, a method in which the controller 120 itself actively reads out the file system from the storage unit 160 can be easily considered.

  In the third operation, the recording / reproducing apparatus reads a value from the internal register 130. The command 800 and data 820 are input from the interface 110 to the command decoder 830. When the command 800 is a read from the internal register 130, the command decoder 830 operates the active area capacity calculation unit 900 to calculate the maximum number of bytes 910 of the active area based on the active area designation register 140, and sets the internal register 130. The internal register conversion means 920 performs conversion. The active area capacity calculation means 900 calculates the maximum number of bytes 910 as M × D, where M is the number of bits whose active area designation register 140 is 1 and D is the capacity of each storage area. If the value of the active area designation register 140 is 0010b and D = 2 GB, the maximum number of bytes 910 is 1 × 2 GB = 2 GB. The internal register conversion means 920 converts only the register in which the maximum number of bytes in the active area is recorded among the internal registers 130. The maximum number of bytes 910 is read as data 820 in the same format as the internal register 130 in accordance with the SD memory card standard. Other registers are not converted, and the read value of the internal register 130 is read as data 820 as it is.

  The operation of the recording medium configured as described above when connected to the recording / reproducing apparatus will be described below. A method for switching storage areas will also be described.

  First, the user of the recording / reproducing apparatus inserts the recording medium of the present invention into the recording / reproducing apparatus and turns on the power of the recording / reproducing apparatus. Since the initial value of the active area switching control signal 670 is 0, 1 is output to the card detection signal 710 and the DET signal 530 is also 1. That is, the recording / reproducing apparatus detects insertion of a card. The recording / reproducing apparatus reads each specification of the recording medium from the recording medium in the initialization procedure. Each specification of the recording medium is stored in an internal register of the recording medium and affects the operation of the recording / reproducing apparatus. Further, the file format (file system) recorded in the recording apparatus also affects the operation of the recording / reproducing apparatus.

  When the recording medium has been formatted, the recording / reproducing apparatus reads the format information of the recording medium from address 0 of the logical address and tries to access the recording medium. At this time, as described in the first operation of the controller 120, the recording medium of the present invention adds the offset calculated by the offset calculation means 840 to the logical address to convert it into a physical address, and accesses the storage means. . That is, the recording / reproducing apparatus accesses the recording medium so that the active area of the recording medium is at logical address 0 without recognizing that there are a plurality of storage areas.

  When the recording medium is unformatted, the recording / reproducing apparatus reads the maximum number of bytes from the internal register of the recording medium and attempts to format the recording medium with a file system that can be handled by the recording / reproducing apparatus. At this time, as described in the second operation of the controller 120, the recording medium of the present invention uses the maximum number of bytes calculated by the active area capacity calculation unit 900 instead of the maximum number of bytes stored in the internal register. To the recording / reproducing apparatus. That is, the recording / reproducing apparatus formats the recording medium on the assumption that the recording medium has only the storage capacity for the active area without recognizing the actual storage capacity of the storage medium.

  Next, the user of the recording / reproducing apparatus stores various data on the recording medium using the function of the recording / reproducing apparatus. For example, it may be still image data of a digital camera or music data of an audio player. As usage by the user progresses, the remaining capacity of the storage medium gradually decreases. At this time, in the recording medium of the present invention, the recording medium can monitor the remaining amount of the active area and automatically switch the active area. In the recording / reproducing apparatus, it is recognized that the card has been removed and a new card with a large free space has been inserted.

  As described above, in the first embodiment of the present invention, the active region is automatically switched when the remaining amount of the active region is reduced by providing the active region designation register and the active region switching means. The active area can be designated from a plurality of storage areas. At the same time, it is possible to cause the recording / reproducing apparatus to detect the insertion / removal of the card by pseudo-insertion / removal.

  In the first embodiment of the present invention, it has been described that the DET signal 530 is simply pulled down. However, some commercially available card sockets include a mechanical switch that mechanically recognizes the insertion state of the card and is connected to the DET signal 530. That is, the DET signal 530 is pulled up when the mechanical switch is on. In this case, even if the card insertion / removal is artificially generated in the recording medium of the present invention, the recording / reproducing apparatus cannot recognize the card insertion / removal. In order to switch the storage area using the recording medium of the present invention, it is necessary to invalidate the mechanical switch of the card socket on the recording / reproducing apparatus side or to use a card socket having no mechanical switch.

  Further, in the first embodiment of the present invention, the division of the storage area has been described with the same capacity. However, by dividing the storage area into different capacities for each storage area, the capacity can be recorded according to the recording / reproducing apparatus. It can be handled as a medium.

  In the first embodiment of the present invention, an SD memory card is assumed as a recording medium. However, a compact flash (registered trademark) or a memory stick (registered trademark) may be used.

  It is to be noted that the present invention has an object to provide a recording medium and a storage area switching method capable of selecting one of a plurality of storage areas without changing the shape defined by the standard. In consideration of the convenience of the user, the currently active storage area may be displayed. A specific example will be described with reference to FIG. FIG. 10 shows the appearance of the recording medium in the first embodiment of the present invention. In FIG. 10, a plurality of LEDs 950 are provided on the back surface of the recording medium. The LED 950 is turned on when it is 1 and turned off when it is 0, corresponding to the value of each bit of the active area designation register. Thereby, even when the recording medium is connected to the recording / reproducing apparatus and used, the user can identify the active recording area. However, the number of LEDs provided and the lighting method of the LEDs are not limited to the above example.

  Further, a means for transmitting to the user that the active storage area has been switched may be provided. For example, there may be a means for transmitting a sound by providing a sound source inside the recording medium, or by transmitting an LED by blinking the LED.

  The recording medium according to the present invention has an active area switching means, and can select one of a plurality of storage areas in the recording medium. When handling a large capacity recording medium in the recording / reproducing apparatus, Useful. In particular, it can be suitably used for a memory card connected to a recording / reproducing apparatus such as a digital camera.

1 is a block diagram of a recording medium in a first embodiment of the present invention. The figure which shows the detail of the interface in 1st Example of this invention The figure which shows the structure of the memory | storage means in 1st Example of this invention. The figure which shows the value of the switching of a storage area and the active area designation | designated register in 1st Example of this invention Block diagram of active area switching means in the first embodiment of the present invention The block diagram of the pseudo insertion / extraction means in the 1st Example of this invention, and the figure which shows the connection with a recording / reproducing apparatus The figure which shows the 1st detailed flow of the active area designation | designated register update means in 1st Example of this invention. The figure which shows the 2nd detailed flow of the active area designation register update means in 1st Example of this invention. Block diagram of the controller in the first embodiment of the present invention 1 is an external view of a recording medium according to a first embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Recording medium 110 Interface 120 Controller 130 Internal register 140 Active area designation register 150 Active area switching means 160 Storage means 161 First storage area 162 Second storage area 163 Third storage area 164 Fourth storage area 200 Interface driver 500 switch 510 resistor 520 VDD
530 DET signal 540 VSS
550 Resistor 610 File System Buffer 620 FAT
630 Remaining capacity detecting means 640 Remaining capacity 650 Switching remaining capacity 660 Active area switching determining means 670 Active area switching control signal 680 Active area specifying register updating means 690 REG
700 pseudo insertion / extraction means 710 card detection signal 800 command 810 response 820 data 830 command decoder 840 offset calculation means 850 offset 860 address acquisition means 870 logical address 880 adder 890 physical address 900 active area capacity calculation means 910 maximum number of bytes 920 internal register conversion Means 950 LED

Claims (8)

In a readable / writable recording medium used by connecting to an external recording / reproducing device,
An interface connected to the recording / reproducing apparatus;
Storage means having a plurality of storage areas;
An internal register that holds characteristic values specific to the recording medium;
A controller for controlling the storage means based on an instruction of the recording / reproducing apparatus or a value of the internal register;
An active area designation register for designating one area of the plurality of storage areas as an active area;
The active area designation register is instructed to switch the active area, and comprises an active area switching means for recognizing the new active area switched to the recording / reproducing apparatus,
The recording medium according to claim 1, wherein the active area switching means determines whether to switch the active area based on a remaining storage capacity of the active area. The active area switching means includes
A remaining amount calculating means for receiving a file system from the controller and calculating the remaining amount of the active area;
An active region switching determination unit that compares the remaining amount with a predetermined threshold and determines switching of the active region;
An active area designation register updating means for updating a value of the active area designation register when the active area switching judgment means determines to switch the active area;
2. The recording medium according to claim 1, further comprising insertion / removal control means for controlling the interface to generate a card insertion / removal signal and causing the recording / reproducing apparatus to detect that the card has been inserted / removed. The controller is
Active area capacity calculating means for calculating the capacity of the active area from the active area designation register;
The recording medium according to claim 1, further comprising an internal register conversion unit that replaces a part of the internal register based on a calculation result of the active area capacity calculation unit. The controller is
Offset calculating means for calculating an offset of an address from the active area designation register;
The recording medium according to claim 1, further comprising: an adder that adds a calculation result of the offset calculation means and an address transmitted from the recording / reproducing apparatus. The controller is
2. The recording medium according to claim 1, further comprising means for storing a file system that is read and written by the recording / reproducing apparatus. 2. The recording medium according to claim 1, further comprising display means for recognizing a storage area designated by the active area designation register from outside. 2. The recording medium according to claim 1, further comprising display means for recognizing from the outside that the storage area designated by the active area designation register has been switched. Read / write for use by connecting to an external recording / playback device.
An interface connected to the recording / reproducing apparatus;
Storage means having a plurality of storage areas;
An internal register that holds characteristic values specific to the recording medium;
A controller for controlling the storage means based on an instruction of the recording / reproducing apparatus or a value of the internal register;
An active area designation register for designating an active area from the plurality of storage areas;
In a recording medium comprising active area switching means for switching the active area based on the remaining amount of the active area,
Reading the file system of the active area;
Calculating the remaining amount of the active area based on the file system;
Comparing the remaining amount with a predetermined threshold and determining switching of the active region;
When it is determined to switch the active area, updating the value of the active area designation register; and
Storage area switching comprising the step of controlling the interface to generate a pseudo card insertion / removal and causing the recording / reproducing device to detect the card insertion / removal when it is determined to switch the active area Method.

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