JPH0468487A - Portable storage medium - Google Patents

Abstract

PURPOSE:To insert new information at a desired position by successively moving respective stored data to idle sectors and producing an idle sector for writing a new data at the desired position. CONSTITUTION:One part or all the parts of a data memory 2 is divided into sectors 5 with a fixed length, and the respective data are stored successively from the sector 5 at the high-order address of the data memory 2. A CPU 1 retrieves the data already stored at a designated position in the data memory 2, and the respective data stored at positions with lower-orders than the position of the data in the data memory 2 are moved for each sector 5 storing each data. Therefore, the idle sector is generated at the designated position in the data memory 2. Thus, new information can be inserted between existent informa tion.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention provides an integrated circuit (IC) chip having a built-in IC (integrated circuit) chip having, for example, a non-volatile memory and a control element such as a CPU.
It relates to a portable storage medium called an IC card.

(Prior Art) Conventionally, EEPROM has been used as a portable data storage medium.
An IC card has been devised that has a built-in IC chip that has a data memory such as a CPU and a control element such as a CPU. The system selectively inputs and outputs necessary information in response to requests from users.

Now, 1. In such an IC card, a plurality of data may be stored in the data memory, but the storage method is to store the data in the order in which it was written from the upper or lower address of the data memory. When storing new data in this data memory, there are two methods: one is to use the empty space in the data memory and add new data here, and the other is to overwrite the existing data with new data. . However, with the former method, new data is added to the end of the permutation of data that has already been stored, so when reading the data, it can only be read in the order in which it was written. Ta. Furthermore, if the latter method is used, the contents of the existing overwritten data will be lost. Therefore, conventional IC
In order to insert new data between data already stored in the data memory of the card, as shown in FIG. A and B of the data to be stored.

This is done by recording dummy data in advance between C and D and overwriting new data E on the dummy data, as shown in FIG. 5(b).

(Problem to be Solved by the Invention) As described above, in a conventional portable storage medium, in order to insert new data between data already stored in the data memory, it is necessary to insert data into the data memory in advance. An area for data insertion must be secured by securing a dummy data area for overwriting. Therefore, there is a problem in that the use efficiency of the area for storing data in the data memory deteriorates.

Therefore, an object of the present invention is to provide a portable storage medium that can insert new information between existing information even if the data memory does not have dummy data for overwriting in advance. .

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the portable storage medium of the present invention includes a storage means for storing a plurality of data, and recognizes the order of each data stored in the storage means. recognition means;
a retrieval means for retrieving specified data from the storage means in accordance with the order of the data recognized by the recognition means; It is characterized by comprising a moving means for moving data stored in a lower order within the storage means.

(Function) The order of data already stored in the data memory (storage means) can be recognized by the recognition means, and when new data is inserted and stored between these data, the order of the data already stored in the data memory (storage means) can be recognized by the retrieval means first. retrieves data already stored at a specified position (sequence) in data memory to store the data to be inserted. Then, each piece of data stored in a position lower than the position of the data in the data memory is moved for each sector in which the data is stored. This creates an empty sector at the specified location in the data memory, so new data is stored there.

(Example) Hereinafter, an example in which the present invention is applied to an IC card will be described with reference to the drawings.

FIG. 1 shows an example of the configuration of an IC card, which includes a control element (hereinafter referred to as CPU) 1 as a control section, a non-volatile data memory 2 whose storage contents can be erased as a data memory section, a program memory 3, and a contact portion 4 for obtaining electrical connection with a card reader/writer (not shown). Of these, the portion within the broken line (CPU 1, data memory 2, program memory 3) is composed of one IC chip and is embedded within the IC card body. The data memory 2 is used to store various data, and is composed of, for example, an EEFROM.

Here, the format of the data storage portion of the data memory 2 is shown in FIG. A part or all of the data memory 2 is divided into fixed-length sectors 5, and each sector 5 is used as a unit to store data sent from a host device. Each piece of data to be stored is stored in sequential order starting from sectors at higher addresses in the data memory.

Now, as shown in FIG. 3(a), four pieces of data, data A, data B, data C, and data D, are stored in the data memory 3, and the order in which they are stored is first, Assume that they are the second, third, and fourth.

At this time, the operation of inserting new data E sent from the host device as the third data between data B and data C will be explained. This is because the CPU (shown in Figure 1) stores data B and C in the second and third positions in the data memory 2, respectively. It starts with moving.

First, the data D is moved to the empty sector next to the sector in which the data D exists in the data memory 3. Next, the CPUI moves the data C to the empty sector next to the sector in which the data C exists in the data memory 2, that is, the sector in which the data D existed before the movement (Fig. 3(b) )).

Then, data E is written in the sector where data C existed (currently an empty sector). Through these operations, data E is inserted as the third data between data B and data C (FIG. 3(C)).

As a result, the order of data in the data memory 2 becomes data A, data B, data E, data C, and data D in order from the highest order.

The above data insertion process will be explained in more detail with reference to the flowchart of FIG. Now, let the number of data stored in the data memory 2 be n, the data stored first in the data memory 2 (that is, stored at the beginning of the data string) be Xl, and the data stored in the data memory 2 be stored in the order n. It is assumed that the th data (that is, stored at the end of the data string) is Xn, and the m-th data in the storage order is Xm. At this time, 1×n. Here, the new data Y sent from the host device is inserted as the m-th data in the storage order between the data Xm-1 in the (m-1)th storage order and the data Xm in the m-th storage order. do. Next, assign n to the parameter P that represents the storage order (Step) o Next, select CPUI (m
1) searches data memory 2 for data Xp in storage order P (Step 2), and then the CPU detects that there is an empty sector below the sector in which data Xp is stored in data memory 2. Judging Gadouga (St
ep3). If an empty sector exists here, the CPU
moves the data Xp to the empty sector that is lower and closest to the sector in which the data is stored (Step 4). When data is moved, the sector where the data was stored before it was moved becomes an empty sector.

Also, if it is determined in step 5 that there is no empty sector, a data insertion failure error will occur (step 8).
Finish the process. 5. When the data is moved in step 4, the value obtained by subtracting "1" from the value of parameter P is then assigned to parameter P (step 5). Then, the value of parameter P and m are compared (Step 6). Here, if the value of parameter P is m or more, 5tep3 to 5tep6
Repeat the process up to. Storage order m in data memory 2
If the movement of all data above n or below is completed, that is, 5
If the value of P becomes less than or equal to m in step 6, the CPUI inserts the data Y into the sector (currently an empty sector) that existed before the data Xm was moved (
Step 7).

Through the above processing, data Y is inserted between data Xm-1 and data Xm. Data Y at this time
The storage order is mth, and the order of each data stored below this data Y is lower by one.

As described above, the IC card of this embodiment moves each piece of data stored in the data memory 2 to empty sectors one after another, thereby creating an empty sector for writing new data at a desired position. can be produced. Then, by writing new data to this empty sector,
New information can be inserted at a desired position without losing pre-stored data or disrupting the order of pre-stored information. Therefore, there is no need to store dummy data in advance in the data memory 2 to overwrite new data to be inserted later.
Data memory 2 can be used effectively.

〔Effect of the invention〕

As described in detail below, according to the present invention, empty sectors can be secured at desired locations in the memory, making it easy to insert new information between already stored information. A portable storage medium that can be used can be provided.

[Brief explanation of the drawing]

1 to 4 are for explaining the present invention in detail, and FIG. 1 is a block diagram showing the structure of an IC card, and FIG.
The figure is a diagram to explain the format of data memory.
Figures 3 (a) to (c) are diagrams for explaining the insertion of data into the data memory, Figure 4 is a flowchart for explaining the flow of data insertion processing, and Figures 5 (a) to (b) are diagrams for explaining the insertion of data into the data memory. FIG. 2 is a diagram for explaining a conventional example. 1... Control element 2... Data memory 5...
Sector agent Patent attorney Nori Chika Ken Yuki Yamashita (a) (b) (c) Figure (a) Figure

Claims (1)

[Claims] a storage means for storing a plurality of data; a recognition means for recognizing the order of each data stored in the storage means;
a search means for searching the storage means for specified data according to the order of data recognized by the recognition means; and a search means for searching data stored in the storage means lower than the order of the data retrieved by the search means. a moving means for moving data stored in the order in the storage means.