JP2538906B2 - IC card - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to, for example, a nonvolatile data memory and
The present invention relates to an IC card containing an IC chip having a control element such as a CPU.

(Prior Art) Recently, as a new portable data storage medium, I has a nonvolatile data memory and a control element such as a CPU.
An IC card with a built-in C chip has been developed. This type of IC card accesses a built-in data memory by a built-in control element and inputs / outputs necessary data in response to a request from an external device. Further, the data memory is divided into a plurality of areas, and the target area is selectively accessed.

Conventionally, in such an IC card, as a data storage method for a data memory, data is arranged and stored in the order of access. According to this method, when there are a plurality of data in the area and some arbitrary data is rewritten, the length of the data before the rewriting and that of the rewriting data must match. This is because, for example, when the former data length is larger than the latter data length, a few bytes (or several words) of white space occur between the data to be rewritten and the next data, and the small data In this case, it is necessary to shift the next data and subsequent data to secure a space for storing the rewrite data.

As a measure against such a drawback, one unit of data to be stored is divided into a plurality of pieces by the concept of word, and each divided data is stored by adding continuous information to each of them, thereby storing the word. A method that gives flexibility to the method is conceivable.

However, in this case, when storing each divided data, if the method of sequentially adding chain information at the same time is stored, for example, power supply to the IC card due to disturbance etc. while all the data is stored If the supply is cut off and the system goes down, if this data is read after the system is restored, the chain information of the incomplete data stored earlier is cut off in the middle, so there is a risk of reading improper data. is there.

(Problems to be Solved by the Invention) As described above, when the divided data is stored, if the chain information is also added at the same time, the system is down due to power shutdown during the storage operation. If
If this data is read out after the system is restored, there is a problem that incorrect data may be read out.

Therefore, the present invention provides an IC card in which the data in the middle of storage is invalidated when the system goes down due to power interruption or the like during the data storage operation, and there is no fear of reading unjust data even if accessed after the system is restored. The purpose is to do.

Further, according to the present invention, as described above, when data is divided into a plurality of pieces and chain information is added to each divided data and stored, which of the data connected by the chain information is the tip. It is easy to recognize whether it is the end or the end, and to identify the next data in word units.
The purpose is to provide an IC card that can effectively use the internal memory.

[Configuration of Invention] (Means for Solving Problems) An IC card of the present invention is an IC card for storing data received from an external device in a built-in memory, and divides the area of the memory into a plurality of areas. A definition area that stores information and definition information that defines the word length of the data in each divided area, and the data is stored in word length units defined in this definition area, and word continuation is associated with each word. And a plurality of data storage areas having an identification information storage unit that stores identification information indicating whether or not the word is head data, and a memory having a plurality of data storage areas Dividing means for dividing the data received from the external device into a plurality of portions based on the word length in the area to which the data is to be written, and each of the dividing means divided by the dividing means. Writing means for writing the data into the data storage area of the memory, holding means for holding the storage position information of each of the divided data when writing the divided data, and all of the divided data. A discriminating means for discriminating whether or not the data is normally stored, and when it is determined by the discriminating means that all of the divided data are normally stored, based on the storage position information held by the holding means. The storage position information of the next word following each word is added to the continuity information storage unit as chain information of each data, and the final data of each data stored in the memory is specified differently from the chain information. First adding means for adding the information of 1 to the continuity information storage section,
Of the data stored in the data storage area of the memory after the determination unit determines that all of the divided data are normally stored and the chain information is added by the first addition unit. The first data is provided with a second adding means for adding identification information for identifying the first data to the identification information storage section of the data storage area.

(Operation) According to the present invention, data received from the outside is divided into a plurality of pieces based on a predetermined word length, and only when all the divided pieces of data are normally stored, the respective pieces of data are respectively stored. By adding chain information, if the system goes down due to power cut during storage operation of each divided data, the data in the middle of storage will be invalid because the chain information is not added yet and will be accessed after system recovery. However, there is no fear of reading unjust data.

Further, according to the present invention, when the chain information is added to each of the divided data, by adding the identification information for identifying the data at the tip of the chain to the data at the tip of the chain, The identification information makes it possible to easily recognize the data at the end of the chain.

Further, according to the present invention, the data storage area of the internal memory is a continuity information storage unit that stores continuity information indicating word continuity corresponding to each word, and whether the word is head data. Since it has an identification information storage unit that stores identification information indicating whether or not it is possible to easily identify the next data, the final data, and the first data in word units.

Further, according to the present invention, information defining the word length of the data is stored in the definition area of the internal memory, and the data is divided based on the information defining the word length, so that the optimum word for each memory area can be obtained. You can set the length and use the internal memory effectively.

(Example) Hereinafter, one example of the present invention will be described with reference to the drawings.

FIG. 9 shows an example of the configuration of a card handling device to which the IC card according to the present invention is applied and which is used as a terminal device such as a financial system or a kopping system. That is, this device has an IC card 1 via a card reader / writer 2 and a control unit 3 including a CPU and the like.
And the keyboard 4,
It is configured by connecting a CRT display device 5, a printer 6 and a floppy disk device 7.

FIG. 8 shows an example of the configuration of the IC card 1. A control element (for example, a CPU) 11 as a control unit, a nonvolatile data memory 12 whose stored contents can be erased, a program memory 13,
And a contact part 14 for making electrical contact with the card reader / writer 2, of which the parts within the broken line (control element 11, data memory 12, program memory 13) are composed of one IC chip. Embedded in the IC card body. The program memory 13 is composed of a mask ROM, for example, and stores a control program for the control element 11 and the like. The data memory 12 is used to store various data and is composed of, for example, an EEPROM.

The data memory 12 is divided into a plurality of areas, for example, as shown in FIG. 5, and area numbers [00, 01, ...] Are given to the respective areas. Of these, in the area [00], the respective start addresses of the areas [01, 02, ...], the number of words dividing the area, and the number of bytes of the word are stored in correspondence with the area number. For example, the start address of area [01] is aaa address, the number of words dividing the area is Wa, and the number of bytes of word is
Correspondence such as Sa byte. Each area [01, 02, ...] Is divided into words having a fixed length (S bytes), and word numbers are given to these words. The word number is indicated by hexadecimal (Hex) data in which the word located at the beginning of the area is set to "1" and sequentially increases by one.

FIG. 6 shows a state in which data is stored in a certain area. Chain information and identification information are added to each divided data. As the chain information, the word number of the word in which the data that follows is stored (that is, the storage position information of the divided data that continues thereafter) is used. The identification information defines whether or not the data is the leading data of the chain. For example, as shown in FIG. 7, 1 byte (8 bits).
It consists of, the most significant bit (MSB) is used and the others are dummy. That is, if the MSB is “0”, it indicates that the data is the head data, and if the MSB is “1”, it indicates that it is other than that.

Next, the data storage system of the present invention having such a configuration will be described in detail. When writing data in the data memory 12, write command data having a format as shown in FIG. 3 is input from the card reader / writer 2 to the IC card 1. In the IC card 1, the control element 11 recognizes the write function code included in the write command data, and executes the write processing based on the flowchart shown in FIG. That is, first, the total number of bytes of write data is recognized based on the data length included in the input write command data, and then it is determined whether or not all the write data can be stored in the access target area. If the data cannot be stored, the response data indicating a byte number error is output and the process ends. If the data can be stored, the write data contained in the input write command data is divided for each byte number of words, and sequentially written in the access target area of the data memory 12 in word units. At this time, the word number of the written word is set to the control element 11
Hold it in the internal RAM temporarily. Then, when it is recognized that all the divided data have been normally written, the word numbers held in the RAM are sequentially added as chain information from the last written word. In this case, the chain information of the last written word is set to "0" to indicate that it is the data at the end of the chain, and the subsequent chain information is allocated sequentially from the word number last held in the RAM. And finally, the MSB of the identification information of the word to which the chain information is assigned is set to “0” to display that it is the data at the end of the chain,
The response data indicating normal termination is output and the processing is terminated.

More specifically, referring to FIG. 6, for example, write data W11, W12, W13 are divided and sequentially written in each word of word numbers "1, 2, 3" in this order. At this time, R
Word numbers “1, 2, 3” are stored in AM in this order. Next, "0" is added to the chain information part of the data W13, "3" is added to the chain information part of the data W12, and "2" is added to the chain information part of the data W11. Then, the MSB of the identification information of the word W11 to which the chain information is added last is set to "0".

Next, when reading data from the data memory 12, read command data having a format as shown in FIG. 4 is input from the card reader / writer 2 to the IC card 1.
In the IC card 1, the control element 11 recognizes the read function code included in the read command data and executes the read process based on the flowchart shown in FIG. That is, first, referring to the identification information section in the access target area,
Find the one whose MSB is "0". If not found, the response data indicating that the data has not been written is output, and the process ends. If found, then counting from the beginning, it is checked whether or not there is a word having "0" or more from the read target data number included in the input read command data. If not, the response data indicating that there is no data number to be read is output and the process ends. If so, the word in which the MSB of the identification information that matches the read data number is "0" is referenced and the data in that word is read.
Hold in RAM temporarily. Next, the word having the following data is recognized by the corresponding chain information, the data in the word is read and added after the data previously held in the RAM. Then, this operation ends when the data of the word whose chain information is "0" is held in the RAM, the data held in the RAM is output, and the processing ends.

In this way, the data received from the outside is divided into a plurality of pieces by the concept of word, and when storing each divided data, chain information to be added to each data is temporarily held and each divided data is stored. Only when all are normally stored, by adding the temporarily stored chain information to each of the respective data, when the system is down due to electrode interruption during the storage operation of each divided data, Since the chain information is not added yet to the data in the middle of storage, it becomes invalid, and even if it is accessed after the system is restored, there is no fear of reading the invalid data.

In addition, when each piece of the divided data is stored with the chain information added thereto, the identification information added to the data to be the end of the chain is specified information (for example, 0). The data can be easily recognized.

Further, the data storage area of the internal data memory indicates a continuity information storage unit that stores continuity information indicating word continuity corresponding to each word and whether or not the word is head data. Since it has an identification information storage section for storing identification information, it is possible to easily identify the next data, the final data, and the beginning data in word units.

Further, by storing information defining the word length of the data in each area divided into the definition areas of the internal data memory, and dividing the data into a plurality of pieces based on the information defining the word length, each memory area The optimum word length can be set for each and the internal data memory can be used effectively.

[Effects of the Invention] As described in detail above, according to the present invention, when the system goes down due to power interruption during the data storage operation, the data in the middle of the storage becomes invalid, and it is not appropriate to access after the system is restored. An IC card without fear of reading data can be provided.

Further, according to the present invention, when the chain information is added to each of the divided data, by adding the identification information for identifying the data at the tip of the chain to the data at the tip of the chain, It is possible to provide an IC card that can easily recognize the data at the end of the chain based on the identification information.

Further, according to the present invention, the data storage area of the internal memory is a continuity information storage unit that stores continuity information indicating word continuity corresponding to each word, and whether the word is head data. Since it has an identification information storage unit that stores identification information indicating whether or not it is possible to provide an IC card in which the identification of the next data, the identification of the final data, and the identification of the beginning data can be easily performed in word units.

Further, according to the present invention, information defining the word length of the data is stored in the definition area of the internal memory, and the data is divided based on the information defining the word length, so that the optimum word for each memory area can be obtained. It is possible to provide an IC card that can set the length and effectively use the internal memory.

[Brief description of drawings]

FIG. 1 is for explaining an embodiment of the present invention, and FIG. 1 is a flow chart for explaining a data writing process, and FIG.
FIG. 4 is a flow chart for explaining a data read process, FIG. 3 is a diagram showing a format example of write command data, FIG. 4 is a diagram showing a format example of read command data, and FIG. 5 is a diagram showing a configuration of a data memory. , FIG. 6 is a diagram showing a state in which data is stored in an area, FIG. 7 is a diagram showing a configuration of identification information, FIG. 8 is a block diagram showing a configuration of an IC card, and FIG. 9 is a configuration of a card handling device. It is a block diagram showing. 1 …… IC card, 2 …… Card reader / writer, 11 ……
Control element (control section), 12 ... Data memory, 13 ... Program memory.

Claims (1)

(57) [Claims] 1. An IC card for storing data received from an external device in a built-in memory, comprising information for dividing an area of the memory into a plurality of pieces and definition information for defining a word length of data in each divided area. And a continuity information storage unit that stores data in units of word lengths defined in this definition area and that stores continuity information indicating word continuity corresponding to each word, A memory having a plurality of data storage areas having an identification information storage unit that stores identification information indicating whether or not a word is the first data, and data received from an external device in an area to which this data is written. Dividing means for dividing the data into a plurality of pieces based on the word length, and a writer for writing each data divided by the dividing means into a data storage area of the memory. And a holding means for holding the storage position information of each divided data when writing the divided data, and a discriminating means for discriminating whether or not all the divided data are normally stored, When it is determined by the discriminating means that all of the divided data are normally stored, the storage position information of the next word following each word is stored in each data based on the storage position information held by the holding means. A first information is added to the continuity information storage unit as chain information, and specific information different from the chain information is added to the continuity information storage unit in the final data of each data stored in the memory. After the addition means and the determination means determine that all of the divided data have been normally stored, and the chain information is added by the first addition means, the memo is added. Second adding means for adding, to the identification information storage section of the data storage area, identification information for identifying the first data among the respective data stored in the data storage area, An IC card characterized by having.