JPS59111555A - Memory circuit - Google Patents

Abstract

PURPOSE:To amplify a program and to shorten an execution time by adding a condition register to a memory circuit, and executing write control to a memory by comparison control. CONSTITUTION:A memory circuit is constituted of a memory 1 for extracting and storing that which satisfies conditions among input data, an address counter 2, a condition register 3, a data register 4, and a comparison controlling circuit 5. Necessary conditions are set to the condition register 3 by a memory write instruction, and these conditions are compared with the contents (input data) of the data register 4. In case when this result of comparison satisfies the conditions, the comparison controlling circuit 5 outputs a write instruction and writes the contents of the data register 4 in the memory 1. Also, this circuit transmits the writing to the address counter 2 simultaneously with the writing and designates the following address. Thereafter, with regard to the input data which satisfies the conditions, the writing is executed successively in the memory 1.

Description

[Detailed description of the invention] The present invention relates to memory circuits.

In general, in office processing and statistical processing that handle large amounts of data, it is often the case that only data that satisfies conditions is extracted and used for processing.

1- For example, suppose that there is data about a human being, and data such as name, gender, age, height, weight, and so on are written.

In this case, since the amount of data is large, it is common to store it on a magnetic disk, magnetic tape, or the like. but,
These storage media require access time, so accessing them multiple times must be avoided. For example, if you want to find the average height, average weight, and distribution of people between the ages of 20 and 30, it is better to Processing that extracts only data related to people up to the age of 10, stores it in IO memory etc. with short access time, and then reads it from IO memory and calculates the average height, average weight, etc. It is desirable to apply

Therefore, if only data that satisfies the conditions is required, it is necessary to extract only the data that satisfies the conditions from a large group of data stored on magnetic disks, magnetic tapes, etc., and write them to IO memory, etc. becomes.

Conventional memory circuits extract only data that satisfies conditions from a file containing a large amount of data.
When writing to memory, it is generally realized by a program.

For example, a program that selects only data on people under the age of 20 from a large amount of data on people and writes it into memory will be shown and explained below.

It is assumed that one piece of data includes the name, gender, etc. of one person.

Step 1) Setting the condition of being under 20 years old Step 2) Loading the data for one person from the file Step 3) If the data meets the condition, Step 4
) Otherwise, go to step 5) Step 4) Write data for one person to memory Step 5) If data remains in the file, go to step 2) The operation of the above program will be explained below.

In step 1), the selection condition of age and the selection condition of 20 or less are set.

In step 2), data for one person is read from a file in which a large amount of data has been written.

In step 3), if the age written in the data is less than 20 years old, proceed to step 4); otherwise,
Conditionally branch to step 5).

In step 4), the data for one person read in step 2) is written into memory.

In step 5), if the other person's data still remains in the file, return to step 2).

Conventional memory circuits use the above processing to select only data on people under 20 years old from a file containing a large amount of data about people and write it into memory, but the conditional branch in step 3) is required. However, this method has the disadvantage that the program becomes complicated and takes a long time to execute.

An object of the present invention is to provide a memory circuit that can simplify programs and shorten execution time.

That is, an object of the present invention is to provide a memory circuit that eliminates the conventional drawbacks, simplifies processing in a program, and shortens execution time.

The memory circuit of the present invention includes a memory, an address register that specifies an address of the memory, a data register that stores write data to be written to the memory, and a condition register that stores write conditions to the memory. , and a comparison control circuit that compares the write data and the write conditions and controls whether or not to write to the memory according to the comparison result.

That is, the memory circuit of the present invention includes a memory, an address register that specifies an address of the memory, a data register that stores data to be written to the memory, a condition register that stores write conditions for the memory, and the data register. (5) A control circuit that compares the contents of the condition register with the contents of the condition register and controls whether or not to write to the memory based on the result of the comparison.

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention.

The memory circuit shown in FIG. 1 includes a memory 1, an address counter 2, a condition register 3, a data register 4, and a comparison control circuit 5.

The operation of the memory circuit shown in FIG. 1 will be explained below.

The memory circuit shown in FIG. 1 operates as follows in response to a memory write command.

1) In the comparison control circuit 5, the conditions set in the condition register 3 and the contents of the data register 4 are compared.

2) Next, the comparison control circuit 5 issues a write command only when the content of the data register 4 satisfies the condition of the condition register 3 based on the result of the comparison in 1) above, and writes the content of the data register 4. is written to memory 1.

3) Comparison control circuit 5 writes to memory 1 and at the same time notifies address counter 2 that writing is to be performed.

4) Address counter 2 is incremented by 1 when it is informed by comparison control circuit 5 that writing is to be performed in memory 1, and points to the next address.

Next, as shown in the embodiment shown in FIG. 1, a program for extracting only data on persons under 20 years of age from the aforementioned large amount of data and writing it into memory will be shown and explained below.

Step 1) Set the condition of being 20 years old or younger in the condition register Step 2) Read the data for one person from the file and set it in the data register Step 3) Write the data for one person to the memory Step 4) Write the data to the file If remains, go to step 2) In step 3), the comparison control circuit 5 compares whether the data read in step 2) satisfies the condition of being 20 years old or younger, and as a result of the comparison, the condition is satisfied. Only when the condition is satisfied, control is performed to write the data into the memory, so only the data of people who are 20 years old or younger are stored in the memory 1.

At this time, the address is +1 only when writing to memory.
Therefore, in the above program 9, data of persons under the age of 20 is stored in a continuous area of the memory.

As described above, a program that uses the memory circuit of the present invention to extract data that satisfies a condition from a large amount of data and writes it to memory is a program that uses the memory circuit of the present invention to extract data that satisfies conditions from a large amount of data and to write it into memory. There is no need for a conditional branch instruction to perform this, which simplifies program processing. Furthermore, the comparison control circuit automatically performs the comparison and determines whether or not to execute the write command based on the comparison result, so that the time required to transfer the command can be shortened.

Therefore, since all of the large amount of data is repeatedly processed by the program, the processing time can be considerably reduced.

By adding a condition register to the memory circuit of the present invention, writing to the memory can be controlled by comparison control, so it is possible to avoid writing unnecessary data to the memory, so the program can be This has the effect of simplifying the process and shortening the execution time.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention. 1...Memory, 2.Old address counter,
3゛...condition register, 4...data register, 5...music/comparison control circuit.

Claims (1)

[Claims] a memory, an address register that specifies an address of the memory, a data register that stores write data to be written to the memory, a condition register that stores conditions for writing to the memory, and a register that stores the write data and the write data. A memory circuit comprising: a comparison control circuit for comparing write conditions and controlling whether or not to write to the memory according to a comparison result.