JPH06224971A - Data change detection system - Google Patents

Abstract

PURPOSE:To detect a data change changing asynchronous in an address area. CONSTITUTION:When data of an area are stored in a buffer section 1, address information for the data stored in the buffer section 1 is sequentially stored in an FIFO 2. A control section 3 always monitors the presence of address information stored in the FIFO 2 and discriminates it that the data of the address are subject to change when the stored address information is present and reads the data of the address from the buffer section 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data change detection system.

[0002]

2. Description of the Related Art FIG. 2 is a block diagram showing an example of a conventional data change detection method.

In this example, as shown in FIG.
And a holding buffer unit 12 that holds the data in the buffer unit 11, a comparing unit 14 that compares the data in the buffer unit 11 and the holding buffer unit 12, and a buffer unit 11, a holding buffer unit 12, and a comparing unit 14. It is composed of a control unit 13.

Next, the operation of this example will be described. First, when the data of a certain address area is stored in the buffer unit 11, the control unit 13 stores the data of the head address stored in the buffer unit 11 and the holding buffer unit that stores the data before the head address. The data read from the 12 corresponding areas is input to the comparison unit 14.

The comparing section 14 compares the data at these two addresses to determine a change in the data. After completion of this comparison, the control unit 13 stores the data read from the buffer unit 11 in the corresponding area of the holding buffer unit 12.

The same comparison is performed for all addresses in the buffer section 11, and after the end address is reached, the operation returns to the head address again and the same operation is repeated.

In this way, change detection of data that changes asynchronously in a certain address area is performed.

[0008]

According to the conventional data change detection method, data that has not changed is read and compared every time, so that the processing speed becomes slower and the number of read data increases as the address area increases. Therefore, there is a problem that it takes time to detect the data after the change.

[0009]

According to the data change detecting method of the present invention, in a data change detecting method of changing asynchronously in a certain address area, a buffer section for temporarily storing data in the certain address area, An address storage unit that stores address information when data is stored in the buffer unit, and a control unit that controls the buffer unit and the address storage unit, wherein the control unit is the address stored in the address storage unit It is characterized in that the presence or absence of information is judged to detect a change in the data.

The storage unit stores the address information in first-in / first-out.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a data change detection system of the present invention.

In this embodiment, a buffer unit 1 for storing data in a certain address area and a first-in first-out memory (hereinafter FIFO) for sequentially storing address information when the data is stored in the buffer unit 1. 2 and
It is composed of a buffer unit 1 and a control unit 3 for controlling the FIFO 2.

Next, the operation of this embodiment will be described.

First, data for a certain area is stored in the buffer unit 1.
Address information when the data is stored in the buffer unit 1 when the data is stored in the FIFO. The control unit 3 constantly monitors the presence or absence of the address information stored in the FIFO 2. If there is a stored address, it is determined that the data at this address has changed, and the data at that address is read from the buffer unit 1. .

As described above, in this embodiment, change detection of data that changes asynchronously in a certain address area is performed.

[0017]

As described above, according to the present invention, since the change of data is judged by the presence or absence of the changed data address, only the changed data is read. Therefore, the change can be detected without affecting the size of the address information.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a data change detection method of the present invention.

FIG. 2 is a block diagram showing an example of a conventional data change detection method.

[Explanation of symbols]

1,11 Buffer part 2 First-in first-out memory (F
IFO) 3,13 Control unit 12 Holding buffer unit 14 Comparison unit

Claims (2)

[Claims] 1. A method for detecting change of data that changes asynchronously in a certain address area, wherein a buffer section for temporarily storing data for the certain address area and address information when the data is stored in the buffer section are provided. An address storage unit for storing and a control unit for controlling the buffer unit and the address storage unit are provided, and the control unit determines the presence or absence of the address information stored in the address storage unit to detect a change in the data. A data change detection method characterized in that 2. The data change detection method according to claim 1, wherein the storage unit stores the address information in first-in first-out.