JP3048199B2 - IC memory card - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IC memory card which is mounted on a computer and which can be accessed as a file system from the computer. With storage means capable of at least once
Regarding memory cards.

[0002]

2. Description of the Related Art In recent years, practical use of IC cards has progressed, and in particular, the use of memory cards as supply media for application programs and data has been widely promoted. Also,
Computers that support this memory card at the OS level are also provided. Usually, in such a computer, it is known that a ROM in a memory card is assigned to a part of a main memory, but many recognize a memory card as a kind of disk. In the latter case, the memory card is allocated as a logical device similar to a flexible disk drive or the like. Therefore, when reading the information in the memory card, the access is performed by designating the number of the logical device and the file name. In this case, the reading of information is generally performed in accordance with file management information (directory, file allocation table, etc.) as in the case of a disk device.

[0003]

Recently, there has been a demand for mounting a readable and writable memory on a memory card along with the sophistication of application programs supplied by the memory card. However, mixing ROM and RAM in the same IC memory card has the following problems, and has a problem that it cannot be easily realized. That is, ROM,
When trying to mix RAMs, a single file system could not cope.

[0004] This problem will be described briefly. In a normal file system, management information of all stored data is collectively collected in a specific area of a disk. The area in which this management information is stored must be a RAM area because it is rewritten by new management information every time data is rewritten. On the other hand, management information on data previously stored in the ROM area is recorded in the ROM area in advance. Therefore, when viewed from a computer having an IC memory card having a mixture of ROM and RAM, a part of the management information of the data stored in the card is the RAM, and a part of the storage unit where the data is actually stored is also the RAM. Such a configuration is required. Such a memory configuration is actually difficult in view of the cost of the IC memory card, the configuration of the memory chip, and the like .

[0005] The IC memory card of the present invention solves such a problem, and an object of the present invention is to make it possible to mix storage means that cannot rewrite data with storage means that can read and write or that can rewrite data at least once. When
Then, the following configuration was adopted.

[0006]

According to the first aspect of the present invention, there is provided an information processing apparatus comprising:
C memory card is mounted on a computer, and is accessible from the computer as a file system.
C memory card, first storage means for storing data written in advance in a file format in a non-rewritable manner;
Second storage means capable of writing and reading data,
C The management information of the file memory card stores a management information storage means for unrewritably stored within said first storage means, the writing operation of data from the computer is made, the management Management information replacement storage means for replacing access to a predetermined area of the information storage means with a predetermined area of the third readable and writable storage means for storing the management information; and The relationship of the replacement is stored in the form of a look-up table in a fourth storage means, and when an access is made to the area in which the replacement has been performed, the lookup stored in the fourth storage means is performed. Referring to the table,
Management information control means for accessing a corresponding area of the third storage means in which file management information is stored; and file management information or file management information stored in the management information storage means in response to access from the computer. A data processing unit for accessing the data of the first storage unit or the second storage unit by referring to the management information of the file stored in the predetermined area of the replaced third storage unit. And

Here, it is preferable that the third storage means and / or the fourth storage means be secured in a predetermined area of the second storage means.

[0008]

In the present specification, “data” means information handled by a computer,
The data is not limited to simple data to be processed, but includes program codes and intermediate codes.

[0010]

When performing a write operation of the computer or La Defense chromatography data for [action] it is configured as described above according to claim 1, wherein the IC memory card, the management information replacement storage unit, predetermined management information storage means The access to the area is replaced with a predetermined area of the readable / writable third storage means, and the file management information is stored. When this replacement is performed, the management information control means stores the replacement relationship in the fourth storage means, and when the replacement area is accessed thereafter,
Based on the relationship stored in the fourth storage unit, the corresponding area of the third storage unit in which the file management information is stored is accessed.

After the fourth storage means stores the replacement relationship, the data processing means, upon access from the computer, executes the management information of the file stored in the management information storage means or the replaced third information. With reference to file management information stored in a predetermined area of the storage means, the data in the first storage means or the data in the second storage means is accessed.

As a result, an IC memory card having first storage means for storing pre-written data in a non-rewritable manner and second storage means for writing / reading data to a computer is provided. Will be accessible as a single file system.

Here, the third storage means and / or the fourth storage means may be constituted by a semiconductor memory different from the second storage means, or these second storage means may be used. There is no problem at all in securing a predetermined area.
In the latter case, the configuration of the memory can be simplified.

[0014]

[0015]

[0016]

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to further clarify the structure and operation of the present invention described above, preferred embodiments of the present invention will be described below. FIG. 1 is a schematic configuration diagram showing an internal configuration of an IC memory card 1 as one embodiment of the present invention and a computer 3 on which the IC memory card 1 is mounted.

As shown, a well-known CPU 5, a ROM 7, a RAM 9 and the like are provided inside the computer 3. Further, in this embodiment, an interface circuit to which the IC memory card 1 is mounted via a connector 10 is provided. 11
Is provided. The interface circuit 11 is a circuit for exchanging addresses, data, and control signals with the IC memory card 1. Computer 3
In the OS, a device driver that handles the IC memory card 1 connected to the interface circuit 11 as a logical device similar to a flexible disk device is incorporated. Accordingly, the CPU 5 operates as if reading and writing data using tracks and sectors.
The memory card 1 can be handled. That is, when accessing the IC memory card 1 from the CPU 5, file management information for managing a file is read out first, and a sector (256 Data is read or written in byte) units.

As shown in FIG. 2, the IC memory card 1 includes a one-chip microprocessor (hereinafter, referred to as MPU) 21 having a built-in ROM, RAM 20, and the like, a ROM 23 as a first storage unit, and a second storage unit. RAM 25, R serving as third storage means and fourth storage means
The memory data bus DDB connected to the OM 23, the RAM 25, and the like is connected to the data bus DB of the interface circuit 11.
A buffer 27 connected to the MPU 21, an inverter 29 for inverting a read / write signal R / W output from the MPU 21,
The MPU 21 includes a built-in RAM 20 and a battery 30 for backing up the RAM 25.

Incidentally, in addition to the data bus DB, the MPU 21 of the IC memory card 1
An address bus AB and other control signals (only a read / write signal R / W is shown) are connected.
A memory address bus ADB is also connected to the ROM 23 and the RAM 25 from 21.

Next, the configuration of the address space inside the IC memory card 1 will be described. FIG. 3 is an explanatory diagram illustrating the configuration of the address space. As shown, “X00
000h ", the chip of ROM23 is arranged,
A chip of the RAM 25 is arranged in the upper space (X
Is a predetermined value determined by the address space of the computer 3). In a predetermined area from the top of the ROM 23, management information CAo for all files stored in the IC memory card 1 is stored. The conversion table LUT and the management information CAa for the RAM arranged in the last area of the RAM 25 are virtual, and are set by an address control routine described later.

Next, an address control routine executed by the IC memory card 1 will be described with reference to FIG. The CPU 5 of the computer 3 is an IC memory card 1
When accessing the file, first, file information is output via the interface circuit 11. The MPU 21 of the IC memory card 1 reads this signal (step S1).
00), it is determined whether writing or reading is performed (step S11).
0).

If it is determined that the file is to be written, it is determined whether the file is a new file (step S120). In the case of a new file, the management information CAo of the file is accessed to specify an area where the management information can be registered, and at the same time, the management information of the new file is used as RAM management information CAa.
Write to the last area of M25 (step S13
0). On the other hand, if it is determined that the file is not a new file, or if it is determined in step S110 that the access from the CPU 5 is to read the file,
Referring to the conversion table LUT for file management, the area where the management information of the file to be accessed exists
A process is performed to specify whether it is placed on the RAM or on the RAM (step S140). Thereafter, a process of reading the file management information from the specified area is performed (step S150).

The file management information is information of a so-called directory or file allocation table (FAT), and is information such as the attribute of the file, the total number of bytes, and a series of existing sectors. After reading the file management information, the file management information is returned to the CPU 5 of the computer 3 (step S160).

The CPU 5 of the computer 3 receives the management information and sequentially outputs the addresses of the files to be accessed successively. The MPU 21 reads the addresses (step S170) and determines whether or not to write (step S170). In step S180, in the case of writing, a write address is output to the RAM 25 via the memory address bus ADB, and the write signal R / W is output at a write level (step S190). On the other hand, in the case of reading, the ROM 23 is connected via the memory address bus ADB.
Alternatively, the read address is output to the RAM 25 together with the read signal R / W at the read level (step S200). After that, the process exits from "NEXT" and ends this routine.

The MPU of the IC memory card 1 described above
According to the address control routine 21, access to the IC memory card 1 is performed as follows. Since the IC memory card 1 is treated as a file system as viewed from the computer 3, the CPU 5
Prior to reading and writing data to the IC memory card 1,
The file management information is always read, and information such as the storage position and attribute of the data body and the file name is read.
These functions are provided as function calls of the OS, and a file can be called or copied by simply specifying a file name. The reason why the file management information is read in advance is to read the data arrangement of the file and prepare for reading or writing of the data body, or to manage the file such that a duplicate file name is not allowed. Hereinafter, description will be made using reference numerals and the like indicating access flows in FIG.

(A) When the CPU 5 reads the contents of the IC memory card 1 Prior to reading data from the IC memory card 1, the CPU 5
File management information CA stored in the head area of the ROM 23
The address corresponding to the address o is output, and the file management information is read. When the MPU 21 receives the file management information reading process, the MPU 21 refers to the conversion table LUT secured in a predetermined area on the RAM 25. If the file has not been written, the MPU 21 Is not registered, so that the MPU 21
The address received from the interface circuit 11 of
The data is directly output to the ROM 23 via the memory address bus ADB.

The ROM 23 receives the address designation, reads out the management information of the corresponding file, and outputs it to the memory data bus DDB. In the case of reading, since the read / write signal R / W becomes high level, the gate terminal G of the line buffer 27 via the inverter 29
Is at a low level, the line buffer 27 is opened,
Data from the ROM 23 is output to the interface circuit 11. By reading this data, the CPU 5
The management information of the file stored in the ROM 23 of the IC memory card 1 can be known. Since the attribute of the file stored in the ROM 23 is read-only, the CPU 5 determines that the file stored in the ROM 23 cannot be rewritten.

Subsequently, the CPU 5 sequentially specifies the addresses of the data area DAo on the ROM 23 according to the read file management information. The MPU 21 outputs the address as it is to the memory address bus ADB, and the data read from the ROM 23 is output to the interface circuit 11 of the computer 3 via the memory data bus DDB and the data bus DB. Thus, the data of the corresponding file is read.

(B) When the CPU 5 Writes a New File When the CPU 5 writes a file to the IC memory card 1, first, the file management information is read () as in the case of reading. In the case of writing a new file, the MPU 21 detects this, and registers the management information for this file in a predetermined area secured at the end of the RAM 25 as the RAM management information CAa. At the same time, the file management information is
Is assigned to a predetermined address of the area where the data is located, and is returned to the computer 3 side.
The information to be converted to the address where the AM management information CAa is actually written is registered in the conversion table LUT. Therefore, when viewed from the CPU 5 of the computer 3, the management information of the file to be written also exists in the same area CAo as the management information on the ROM 23.

Using this management information, the CPU 5 sequentially outputs addresses to which data is to be written, and the data of the file is written to the area DAa on the RAM 25 (see the broken line). On the other hand, when reading a file written in the RAM 25, the CPU 5 first reads file management information. When reading the management information area CAo, if there is a file written in the RAM 25, the management information is actually stored in the RAM 25 for the portion where the conversion address is written in the conversion table LUT.
The above management information CAa is read (). Based on this information, the CPU 5 sequentially outputs addresses at which data is actually stored. This address is provided from the MPU 21 to the RAM 25 via the memory address bus ADB, and the corresponding data is output to the interface circuit 11 of the computer 3 via the memory data bus DDB and the data bus DB (see broken lines). . Therefore, C
The PU 5 can read the data written in the RAM 25 using a file system.

As described above, according to the IC memory card 1 of this embodiment, the ROM 23 and the RAM 25 can be handled as a single file system from the CPU 5 of the computer 3 while the ROM 23 and the RAM 25 are mixed. Moreover, for that purpose, not only the hardware on the computer 3 side,
No change of software such as an application program, an OS, and a print driver is required. Therefore,
The application program is stored in the ROM 23, and R
The AM 25 can be used to store data necessary for the execution of the application program and data that may be rewritten by the execution of the application program. Conventionally, such data has to be stored in another external storage device or the like, and installation work such as which logical device should be used to create a file has been required. According to the present embodiment, such a problem is solved.

Further, in this embodiment, since the initial value of the file management information is stored in the ROM 23, the data in the case where the data in the IC memory card 1 is abnormal due to a momentary power failure or the like is stored. It has the advantage of excellent reliability and recoverability of the system to a usable state.

Note that the battery 30 is stored in the IC memory card 1.
Is built in and the RAM 25 is backed up, so that the stored contents can be retained even if the IC memory card 1 is inserted and removed from the computer 3. In this case, data such as environment setting values of the application program may be rewritten by use of the application program.
It can be stored in the C memory card 1, and the usability of the application program is improved. When the battery 30 is not present, when the IC memory card 1 is removed and inserted, the MPU 21 is reset and the conversion table LUT
And management information is lost.

In this embodiment, the conversion table LUT
Is stored in a predetermined area in the RAM 25.
It may be stored in the RAM 20 built in the memory card 1. Further, the management information of the file stored in the RAM 25 may be stored in the built-in RAM 20. In the present embodiment, these are all stored in RAM
25, there is an advantage that the memory configuration is simplified. On the other hand, if part or all of the conversion table LUT and the file management information are stored in the built-in RAM 20, the RAM 25 that can be used for storing files is stored.
This has the advantage that the area can be widened.

A configuration in which a ROM and a RAM are mixed and used as a single file system is shown in FIG.
As shown in (1), a configuration in which the file management information stored in the ROM is temporarily transferred to the RAM area, and then the file management information is read and written using the file management information CAa secured on the RAM area is also considered. However, in this case, immediately after power-on, the MPU 21 needs to perform a process of transferring the management information CAo in the ROM.
If there are many files in the OM and the management information is large,
It takes time.

As another embodiment, instead of the RAM 25 of the IC memory card 1 shown in FIG.
One using an EPROM or a small ROM (a fuse ROM or the like can also be used) is conceivable. This configuration is used to fix bugs in the data in the ROM
3 is used to upgrade the version of data. That is, the conversion table LUT and the file management information are written into the EEPROM or the flash memory together with the new data, and the readout of the data thereafter is performed using the RO.
The data in the rewritten EEPROM or the like is output instead of the data in M23. In this case, the ROM
Since it is not necessary to completely rewrite 23, it is possible to easily cope with a bug fix or the like, and it is possible to reduce the production cost of the IC memory card 1.

The embodiments of the present invention have been described above.
The present invention is not limited to such an embodiment. For example, the data stored in the ROM 23 in the IC memory card 1 is compressed, and the data is read out from the CPU 5 by the MPU 21 to expand the data. It is needless to say that the present invention can be carried out in various modes without departing from the gist of the present invention, such as a configuration for outputting to the third side and a configuration for performing conversion by a logic circuit instead of the address conversion processing by software by the MPU 21. .

[0039]

As described above, according to claim 1,
The C memory card has an excellent effect that it is possible to treat a single file system while mixing a rewritable storage unit and a non-rewritable storage unit. Moreover, there is no need to consider the arrangement of the rewritable storage means and the non-rewritable storage means, and data can be read out in the same manner as a normal ROM card or RAM card. Therefore, no burden is imposed on the development of the OS and the application program in the computer that can use the IC memory card.

[0040]

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an IC memory card 1 and a computer 3 according to an embodiment of the present invention.

FIG. 2 is a block diagram showing an internal configuration of the IC memory card 1 in the embodiment.

FIG. 3 is an explanatory diagram showing a state of access to the IC memory card 1.

FIG. 4 is a flowchart showing an address control routine executed by the MPU 21 of the IC memory card 1.

FIG. 5 is an explanatory diagram showing another configuration example of the IC memory card 1.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... IC memory card 3 ... Computer 5 ... CPU 7 ... ROM 9 ... RAM 10 ... Connector 11 ... Interface circuit 20 ... RAM 21 ... MPU 23 ... ROM 25 ... RAM 27 ... Line buffer 29 ... Inverter 30 ... Battery

Claims (2)

(57) [Claims] 1. An IC memory card mounted on a computer and accessible from the computer as a file system, comprising: first storage means for storing data written in advance in a file format in a non-rewritable manner; A second storage unit capable of writing and reading data, a management information storage unit storing the management information of a file stored in the IC memory card in a non-rewritable manner inside the first storage unit, and the computer When the write operation of data is performed from the access to a predetermined area of the management information storage means, substituting the predetermined region of the third storage means readable and writable perform storage of the management information And a management information replacement storage means for storing, and when the replacement is performed, the relationship of the replacement is stored in a fourth storage means in the form of a look-up table. In both cases, when an access is made to the replaced area, the third storage unit storing the file management information is referred to by referring to the lookup table stored in the fourth storage unit. Management information control means for accessing a corresponding area of the means; and management information of a file stored in the management information storage means or stored in a predetermined area of the replaced third storage means in response to access from the computer. An IC memory card comprising: a data processing unit for accessing data in the first storage unit or the second storage unit by referring to the management information of the file. 2. The IC memory card according to claim 1, wherein said third storage means and / or said fourth storage means are secured in a predetermined area of said second storage means.