JPS6143387A - IC card information processing method - Google Patents

Abstract

PURPOSE:To secure application of a normal memory despite existence of an unusable address by setting a substitute address in place of the unusable address and giving an access to the substitute address in place of the unusable address in a memory access mode. CONSTITUTION:The specific areas are set to a memory 4 for an address where the data on an unusable address is stored and a substitute address where the information to be written to said unusable address is written. Then an access is given to the substitute address in place of the unusable address when an access is given to the memory 4 from a terminal equipment via a microcomputer 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an IC card incorporating an integrated circuit (hereinafter abbreviated as IC) for storing information.

[Technical background of the invention and its problems]

2. Description of the Related Art As an alternative to a magnetic card, a so-called IC card, which has an information processing function and incorporates an IC chip with an excellent information storage capacity, has recently attracted attention.

One type of IC card includes a microcomputer and memory inside the card, and the microprocessor performs processing such as writing, reading, and calculating information such as data or programs to the memory in response to instructions from outside the card.
It has a function of outputting information according to the command to the outside of the card. Such an IC card allows a user to write an application program or data by specifying an address in the memory depending on the program of the microcomputer in the card, and performs a functional test of the bus line of the memory. However, once-written read-only memory 1.1 (
When using FROM), a normal functional test is performed, that is, writing some information to an arbitrarily selected address in the memory, reading out the written information, and comparing it with the original information to see if it matches. Because it is p a OM, the written information cannot be erased,
An inconvenience arises when a user freely writes to a memory area because there are already written addresses.

Furthermore, when a user writes information to a certain address in the memory, there may be an address that cannot be written to even after several attempts.

In such a case, if left as is, the user's memory usage will be hindered, just as in the case where the above test information is written, and sometimes the IC card in question may be unable to write that 1 byte even though other areas of the memory are normal. Because it is not possible to do so, it may be determined to be defective and may be discarded.

As mentioned above, if test data is written in the memory of the IC card, or if there is an address with a write failure, that is, if there is an unusable address, the user must:
Either information must be written into the memory while checking unusable addresses, or the IC card must be discarded as a defective product.The former is extremely troublesome, and the latter is not only uneconomical but also reduces the reliability of the IC card. It will also affect the evaluation of sex.

Note that the user referred to in this specification refers to a person who can write information such as an application program and data to an arbitrary memory address in the memory of an IC card, as described above.

[Purpose of the invention]

An object of the present invention is to solve the above-mentioned drawbacks of the prior art, and to provide information on an IC card that allows the memory to be treated as if it were a completely normal memory even if there is an unusable address in the memory. The purpose is to provide a processing method.

[Summary of the invention]

The present invention, which has been made to achieve the above object, is an information processing method for an IC card equipped with at least a memory, in which an alternative address is set in place of an unusable address existing in the memory, and the unusable address , and accesses an alternative address in place of the unusable address when accessing the memory.
This is an information processing method for a C card.

[Detailed description of the invention]

This invention will be explained in detail below based on some examples.

(2) is an IC card, which includes a microcombiator (3) and a memory (4) connected to the microcomputer (3) by an address bus (5) and a data bus (6). ) is provided. IC card (
1) An external connection terminal from the front side microcomputer (3) is exposed, and the microcomputer (3) and the terminal device (1) are electrically connected through this external connection terminal to enable data communication.

As already mentioned, note! J (4) K Write-once type (erasure and reexamination impossible) read-only memory (P
4'LOM), the address where information is written for testing the memory bus line will become unusable, and the memory (4) (including all semiconductor memories such as AIVf and ROM) may be accidentally damaged. Naturally, even if an unwritable address exists, that address becomes unusable, and the following measures are taken so that even if such an unusable address exists, the use of the memory will not be hindered.

That is, as is clear from the memory map of the memory (4) shown in FIG. 2, there is an area for an address for storing address data of an unusable address and an alternative address for writing information scheduled to be written to the unusable address. (Set the force to memory (4). For example, set the force to memory (4).
) when using up to 154 bytes of memory,
2 to store address data of unavailable addresses
All you need to do is take an area of 3 bytes, 1 byte for the alternative address.

Note that (8) is a system use area where the manufacturer's maintenance data such as the card's serial number, manufacturer, date of manufacture, and program name is stored, and (9) is a user area.

Furthermore, in this embodiment, both the address and alternative address areas for writing the address data of the unusable address (although they are set to 1, it is not possible to separate them into separate areas).

Next, the memory (4) having such a storage area is set so that even if an unusable address exists, it will not hinder the user's use of the memory (4),
The processing program stored in the microcomputer (3) will be explained based on FIGS. 3 and 4.

Figure 3 shows the FR of memory (4) with memory capacity 2 and bytes.
12 is a flowchart of a processing program when OM is used and an unusable address occurs due to a memory bus line test.

In this state, first, it is checked whether the address specified by the user through the terminal (1) to write information is within the user area, and if it is not within the range, the address specification error is set as the status. Inform the user of the error.

If it is an executable address, then the address data is compared with the unusable address data stored in the area (force), and if they match, the address is an unusable address that has already been used for testing. It turns out that
Set an alternative address in area (7). In the figure, addresses 32, 64, ... 512, and 1024 are used in the user area (9) for testing, and these addresses are specified by the user. If the information is written in each area (alternative address m address +1 for address 9), and the information to be written in the unavailable address is written in each area (alternative address in the force). Similarly, when reading information, if the address is found to be unusable, information at a predetermined alternative address is read out.

FIG. 4 is a flowchart of the processing program when there is a writing defective address in the memo (January 4).

In this case, unlike when an unusable address is generated by the above-described test, the write defective address is not known in advance, so it must be confirmed first.

That is, when an address is specified by the user, the write number counter n is cleared and data is written to the specified address. The data written immediately after is compared with the data read and given, and if they match, it is assumed that writing has been performed normally, and either the next address is written or the writing is completed. If they do not match, rewrite the data a predetermined number of times (e.g. n·3 times).If the data written to that address does not match the given data, the address is The address data is stored in area (7) of the memory as being unusable, and the data that was scheduled to be written to that address is written to the area (an alternative address).

Note that if such unusable addresses reach a certain limit (for example, 10 bytes in the case of PROMO with memory capacity of 2 bytes), the memory IC itself may be defective, and the IC card Sets the status that an update is required.

Here, to explain in more detail the address specification mentioned at the beginning, as shown in Figure 5, when an address is specified by the user, it is determined whether or not the address is within the user area (9). is done and is not within the user area (9), the status is set as an address specification error.

On the other hand, if the address is executable, it is first determined whether address data of a non-writable address is registered in the area (force), and if it is not registered at all, the specified address is transferred to the memory address of the IC card. Output to.

When address data of a non-writable address is registered in area (7), it is checked whether the address data of the specified address matches the address data of the non-writable address. If they match, the address data of the corresponding alternative address is output to the IC card memory address, and if they do not match, the address data of the next stored alternative address to be written is output to the IC card memory address.
It will be output to the memory address bus of the C card.

In this way, the address will be specified,
In the case of information reading as well as information writing, it is possible to avoid unusable addresses and read data written to alternative addresses according to the routine shown in FIG.

Note that even if there is an address that has become unusable due to the memory test described above, it is possible to process it using the concept shown in FIGS. 4 and 5.

Furthermore, in this embodiment, an IC card is provided with a microcomputer (3) and a memory (4), and the microcomputer (3) performs the above information processing. Even in a so-called memory card equipped with a memory card, the above information processing is performed on the terminal (1) side, and by providing an area for storing address data of unusable addresses and an area for alternative addresses in the memory of the industrial C card, the memory can be improved. Even if there is an address that cannot be used, this can be handled without any problem.

〔Effect of the invention〕

As described above, according to the present invention, when PR, OM is used in the memory of an IC card and data is written to a certain address for a memory bus line test, data cannot be erased from that address. becomes unusable,
In addition, even with other types of memory, there may be addresses that cannot be written to for some reason, and in the presence of such unusable addresses, it is necessary to specify the address in that memory, write programs, etc., and read it. Even if such an address occurs, it is possible to solve various inconveniences caused by the existence of an unusable address.

That is, the user can write information (as if there were no unusable addresses) without performing complex address calculations to avoid unusable addresses and without worrying about unusable addresses. It also has excellent effects such as being able to eliminate the uneconomical situation of discarding the Memo+7 IC itself as a defective product due to the presence of one unusable address. It is something to play.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; FIG. 1 is a block diagram of an IC card of the present invention, FIG. 2 is a memory map, and FIGS. 3 to 5 are flowcharts showing procedures of the present invention. (1)...Terminal (2)...IC card (3)...Microcomputer (4)
)...Memory (5)...Address bus (6)...Data bus (7)...
・・Area for address data storage of unusable addresses and alternative addresses

Claims (1)

[Claims] 1) In an information processing method for an IC card having at least a memory, an alternative address is set in place of an unusable address existing in the memory, and address data of the unusable address is stored. An information processing method for an IC card, characterized in that an alternative address is accessed in place of the unusable address based on the unusable address data at the time of memory access. 2) The IC according to claim 1, wherein the memory is a write-once read-only memory, and an address used for a bus line function test of the memory is set as an unusable address as an alternative address. How the card processes information. 3) It is determined whether or not information can be written normally to a certain address in the memory, and when information cannot be written normally, the address is set as an unusable address and an alternative address is set. An information processing method for an IC card according to item 1. 4) Repeatedly write the same information to the same address, read it immediately after, and compare it with the given information to confirm. If there is a mismatch, repeat the above procedure. If the write cannot be performed normally even after repeating the specified number of times, the relevant An information processing method for an IC card according to claim 5, wherein the address is an unusable address. 5) The IC card according to claim 3, wherein the memory IC is determined to be defective when the number of unusable addresses reaches a predetermined number.