JP3100146U - Storage device with compression management mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a storage device having the best compression management mechanism.
SOLUTION: It mainly comprises a controller and at least one solid state storage medium. The controller includes a system interface connected to a system end, a microprocessor for processing system commands, and a memory interface capable of exchanging data with the solid state storage medium. The controller reads the type of the original data to be stored and selects the most suitable data compression calculation method for the original data and the corresponding parameter list. Thus, the original data transmitted from the external system end is compressed at the best ratio, becomes extremely small data of the minimum storage unit, and is written to the solid state storage medium.
[Selection diagram] Fig. 1

Description

The present invention relates to a storage device having a kind of best compression management mechanism, and more particularly to a storage device which selects a kind of optimum compression operation method by itself and performs the best compression for data to be stored.

At present, semiconductor memories are becoming increasingly popular as solid state media such as flash memories. Semiconductor memory has the advantages of low power consumption, high reliability, high capacity, high read / write speed, etc., so that CF (Compact Flash Card), MS (registered trademark Memory Stick Card), SD (registered trademark) Widely applied as a small memory card such as Secure Digital Card), MMC (registered trademark MultiMedia Card), SM (registered trademark Memory Stick Card), and a storage device such as a USB mobile disk. ing.
As shown in FIG. 7, these storage devices A have a built-in solid state storage medium A2 and a controller A1. The controller A1 includes a system interface A11 connected to the external system end 2, a microprocessor A12 for processing system commands, and a memory interface A13 capable of exchanging data with the solid state storage medium A2. Further, the external system end 2 writes data to be stored in the solid state storage medium A2, or reads necessary data from the solid state storage medium A2.

However, for storage media such as small memory cards and USB mobile disks, the amount of capacity of the built-in solid state storage media is determined by the production cost and selling price. The storage capacities of currently popular solid state storage media include 64 MB, 128 MB, 256 MB, and the like, and the cost and selling price are directly proportional to the capacity. That is, the greater the capacity of the solid state storage medium, the higher the price.
However, as hardware manufacturing technology has reached a certain level, no significant development is expected in the size and standard of solid state storage media, and it faces the same difficulties as CD-Rs. That is, it is unlikely that the storage capacity will increase significantly in the future.
There is also a technology for minimizing the storage space by nanotechnology and increasing the storage capacity, but this technology is still in its germinating stage and has not yet met the needs for increasing the storage capacity.

On the other hand, in order to solve the shortage of storage capacity, a method of expanding a memory capacity by installing a slot at an appropriate position on a main body of a storage medium such as a small memory card and a USB mobile disk and inserting and connecting an external memory card to the slot. There is also. However, this method has the disadvantage that an external memory card must be purchased.
If you do not purchase external memory cards or solid state storage media, you will need to compress your data. Data compression reduces the amount of data and increases the storage capacity of solid-state storage media, but at present data compression operations can only be performed by computer systems. In this case, use appropriate compression software such as Winrar or Winzip to expand the storage space and obtain a good transmission rate. After compressing the file data, use an internal storage device such as a hard disk, optical disk, or flexible disk. The data is stored in an external storage medium such as a magnetic disk, a USB mobile disk, and an electronic memory card.
Japanese Patent No. 3389186

The present invention solves the above-mentioned disadvantages of the known structure, and the problem is that the solid state storage medium can store more data, reduce the cost, and increase the read / write speed. To provide a storage device with the best compression management mechanism that can select the best compression technology by itself, compress data and make it extremely small, and increase the amount of data stored on solid state storage media. That is.

In order to solve the above problems, the present invention mainly comprises a controller, at least one solid state storage medium, a system interface connected to an external system end, a microprocessor for processing system commands, the solid state A memory interface capable of exchanging data with a storage medium, a data compression / decompression module disposed between the system interface and the memory interface, for compressing original data to be stored at a fixed compression ratio, In order to achieve the best compression technique, the data compression / decompression module includes a data compression circuit and a plurality of operation method descriptors corresponding to the data compression circuit. Comprising, wherein the microprocessor performs a read with respect to type of the original data to be transmitted through the system interface, to select an optimal operation method descriptor type of its own the data. As a result, the data compression circuit compresses the original data based on the optimal operation method descriptor to become extremely small data having a minimum storage unit, which is written to the solid state storage medium. The minute data is recorded and stored in the solid state storage medium through the transmission of the memory interface.

That is, according to the invention of claim 1, a storage device is constituted by a controller and at least one solid state storage medium, a system interface connected to a system end installed in advance outside the controller, and a microprocessor for processing system commands. A memory interface capable of exchanging data with the solid state storage medium, a microprocessor electrically connected between the system interface and the memory interface, and further used in combination with the data compression circuit and the data compression circuit And a data compression / decompression module for a plurality of algorithm descriptors and parameter lists to be transmitted. And selects an optimal combination of compression functions for the type of the original data from the array combination of the algorithm descriptor and the parameter list, and the data compression circuit compresses the original data based on the optimal compression combination. Best compression management, wherein the reduced data having a minimum storage unit is recorded and stored in the solid state storage medium through transmission of the memory interface. It is a storage device with a mechanism.

The invention of claim 2 wherein the solid state storage medium stores an optimal algorithm descriptor and an index index of a parameter list corresponding to the reduced data. It is a storage device equipped.

4. The invention of claim 3 wherein the data compression / decompression module comprises a data decompression circuit, which reads the index index from the solid state storage medium via the microprocessor trigger, thereby reducing the corresponding index. 3. The storage device with the best compression management mechanism according to claim 2, wherein the data is decompressed and returned to the original data based on the operation method descriptor and the parameter list indicated by the index.

The invention of claim 4 wherein the storage device comprises a first data buffer, the first data buffer being electrically connected to a system interface, a microprocessor, and a data compression / decompression module. Storage device with the best compression management mechanism.

The invention of claim 5 wherein a second data buffer is provided in the controller, the second data buffer being electrically connected to a memory interface, a microprocessor, and a data compression / decompression module. 10 is a storage device with the best compression management mechanism described.

The present invention is a storage device with the best compression management mechanism. By compressing data greatly through the internal compression system, the solid state storage media can store more data. Thus, the object of increasing the data storage amount can be achieved, at the same time, the cost can be reduced and the writing / reading speed can be increased. In addition, it is possible to select the best compression technique by itself, compress the data and make it extremely small, and increase the data storage amount of the solid state storage medium.

The present invention selects the best compression algorithm by itself and performs the best compression on the data to be stored, but the storage device with the best compression management mechanism greatly compresses the data through the internal compression system. As a result, solid state storage media can store more data, achieve the purpose of increasing data storage capacity, at the same time reduce costs, increase write and read speed, and select the best compression technology by themselves However, the data can be compressed and extremely miniaturized, and the data storage amount of the solid state storage medium can be increased.
Next, a preferred embodiment of the present invention will be described with reference to the drawings.

The general configuration of the storage device 1 is, as shown in FIG. 1, a memory card type widely applied to various portable digital products at present, a USB mobile disk applied to PC, or a research and development stage at present. Solid state storage media (ie, flash memory).
The storage device 1 includes a controller 10 and at least one solid state storage medium 20. The controller 10 includes a system interface 104, a microprocessor 102, and a memory interface 106. The system interface 104 is connected to a system end 2 (applied equipment such as the various portable digital products and a PC system) installed in advance outside.
The memory interface 106 can exchange data with the solid state storage medium 20, and the microprocessor 102 connects to the system interface 104 and the memory interface 106.

Further, as shown in FIG. 1, in the embodiment of the present invention, a data compression / decompression module 108 is installed in the storage device 1 in order to increase the storage capacity of the solid state storage medium 20. The data compression / decompression module 108 corresponds between the system interface 104 and the memory interface 106 and is electrically connected to the microprocessor 102.
Also, in order to cope with the difference in transmission speed between each interface, a first data buffer 110 and a second data buffer 120 are provided in the controller, and the first data buffer 110 is provided with the data compression / decompression module 108 and the It is electrically connected to the system interface 104 and serves as a front-end buffer of the data compression / decompression module 108.
The second data buffer 120 is electrically connected to the data compression / decompression module 108 and the memory interface 106, and serves as a back-end buffer for the data compression / decompression module 108, and the first and second data buffers 110 and 120 store data. Perform a temporary save of

When the original data is to be stored on the solid-state storage medium 20 of the storage device 1, the system interface 104 receives the original data transmitted by the external system end 2, and then the microprocessor 102 has the features of the present invention. The original data is compressed at an appropriate ratio using the compression mechanism in the data compression / decompression module 108, which is uniquely designed. Thus, the data is reduced, and then recorded and stored on the solid state storage medium 20 by the memory interface 106.
As described above, according to the embodiment of the present invention, by using the design of the compression mechanism, the solid state storage medium 20 can store data of several times the capacity before compression.

In the design of the embodiment of the present invention, the system interface 104 temporarily stores the original data in the first data buffer 110 before compressing the transmitted original data. Next, the original data is read from the first data buffer 110 at a constant transmission rate by the system interface 104 and compressed. Further, the compressed reduced data is transmitted to the second data buffer 120 and temporarily stored.
At this time, under the control of the microprocessor 102, the reduced data temporarily stored in the second data buffer 120 is recorded and stored in the solid state storage medium 20 through the memory interface 106.

Conversely, in the decompression mode, the decompression mechanism in the data compression / decompression module 108 is used to read out reduced data from the solid state storage medium 20 through the memory interface 106 and perform decompression processing.
At this time, the second data buffer 120 temporarily stores the reduced data to be decompressed, and the first data buffer 110 temporarily stores the original data that has already been decompressed and restored to its original state. Next, the original data whose decompression process has been completed and whose original state has been restored is transmitted to the external system end 2 through the system interface 104.

Next, the configuration and operation of compression / decompression will be described. As shown in FIG. 2, the data to be transmitted by the external system end 2 and to be stored and recorded on the solid state storage medium 20 is, in addition to the original data, It is necessary to store the control data of the original data at the same time.
On the other hand, the solid state storage medium 20 is composed of a few data recording blocks 4. In this embodiment, each data recording block 4 occupies 528 bytes of the storage space. Each data recording block 4 has a data recording area 42 (occupying 512 bytes and the same size as a hard disk sector) for storing data and a control information recording area 44 (occupying 16 bytes) for storing control data. . The control information stored in the control information recording area 44 includes control-related information such as a status flag 441, an error correction code 442, and a logic address record 443, as well as an unused holding space 444 (see FIG. 2). Including. In the present invention, in the best process of compression / decompression, the storage space 444 is used as a storage space for the compression record.

Details of the data compression / decompression module 108 shown in FIG. 1 include, as shown in FIG. 3, a data compression circuit 1082, and a plurality of operation method descriptors 1083a to 1083n used in correspondence with the data compression circuit 1082, and The parameter lists 1084a to 1084n are provided.
The operation method descriptors 1083a to 1083n define one kind of compression / decompression operation method, and each kind of compression / decompression operation method can combine various kinds of parameter lists. Can be compressed to the minimum storage unit to obtain reduced data.

First, the microprocessor 102 in FIG. 1 determines the type of the original data transmitted by the system interface 104 and determines the optimal compression combination. The method by which the microprocessor 102 reads the data type is to read the original data. Judgment is made based on the binary distribution form to be constituted. In other words, the optimal calculation method rule is determined based on factors such as the ratio occupied by the "0" and "1" bytes constituting the original data and the degree of concentration or dispersion, and the overlapping phenomenon of a specific distribution form.
After reading the data type, the microprocessor 102 selects an optimal combination of compression operations for the data type from the array combination of the operation method descriptor 1083 group and the parameter list 1084 group. The optimum compression combination is executed through the data compression circuit 1082 to compress the original data.
As a result, reduced data having a minimum storage unit is obtained and temporarily stored in the second data buffer 120. Further, the memory interface 106 is inspired to record the reduced data on the solid state storage medium 20, At the same time, it is stored in the solid state storage medium 20 corresponding to the optimal operation method descriptor of the reduced data and the index index of the parameter.
In FIG. 2, the reduced data is stored in the data recording section 42 of the data recording block 4, and in the embodiment of the present invention, the index index generated by the compression is stored in the storage space 444 of the data recording block 4. save.

The data compression / decompression module 108 includes a data decompression circuit 1085. When reading / storing data in the storage medium 1 at the external system end 2, the memory interface 106 is connected to the solid state through the trigger of the microprocessor 102. The stored index index is read from the reserved space 444 of the storage medium 20.
The algorithm descriptor and parameter list pointed to by the index index decompress the reduced data it corresponds to and store back to the original data, and then transmit the original data to the external system end through the system interface 104 I do.

As shown in FIGS. 4 and 5, when externally transmitted original data enters the first data buffer 110, the microprocessor 102 interprets the binary distribution of the original data through the microprocessor 102. Subsequently, an optimal compression combination for the distribution form is selected from the algorithm descriptor 1083 group and the parameter list 1084 group.
In the present embodiment, the first algorithm descriptor 1083a and the second parameter list 1084b used in combination with the first algorithm descriptor 1083a are selected and set as the compression combination (1, 2) of the format in FIG.
Next, the data compression circuit 1082 in the data compression / decompression module 108 is activated, and the compression combination (1, 2) is used as the basis for the original data compression by the data compression circuit 1082.
In the present embodiment, the compression combination (1, 2) compresses the original data at a ratio of 1/2 (if the original data occupies a space of 512 bytes, it becomes 256 bytes after compression). . As a result, in the data recording block 4 in FIG. 4, the data recording section 42 in which only one original data could be originally stored is reduced by two in the same data recording section 42 after the compression work. Data can be stored.

When saving the compressed original data, the status flag 441, the error correction code 442, and the logic address record 443 in the control information recording area 44 are not changed, and two sets of index indices (1, 2) is newly generated. The first numerical value and the second numerical value in the index index (1, 2) indicate the first algorithm descriptor and the second parameter list to which the reduced data applies, respectively. Decryption processing can be performed.

As shown in FIGS. 4 and 6, when the controller receives the data that the system end requests to be read, the controller finds the logic address corresponding to the data based on the logic address record 443 of the data, and retrieves the logic address corresponding to the data. The data recording block 4 corresponding to and stored in is determined. Further, the content stored in the data recording block 4 is read from the solid state storage medium 20 and sent to the second data buffer 120. Subsequently, the microprocessor activates the data decompression circuit 1085.
At this time, the data decompression circuit 1085 reads and records the index index (1, 2) stored in the storage space 444 of the same data recording block 4, and based on the instruction of the index index, the first algorithm descriptor and the second Read the parameter list and decompress the original data correctly. Next, the original data that has been decompressed and restored to its original state is transmitted to the first data buffer 110, and transmitted to the external system end 2.

FIG. 4 is a schematic circuit diagram of an embodiment of the present invention. FIG. 2 is an explanatory diagram showing the contents of a format included in an uncompressed solid state storage medium in FIG. 1. FIG. 4 is a schematic circuit diagram illustrating the operation of the embodiment of the present invention. FIG. 4 is an explanatory diagram showing contents of a format provided in the solid state storage medium after completion of compression in FIG. 3. FIG. 4 is a compression dynamic diagram in FIG. 3 of the embodiment of the present invention. FIG. 4 is a thawing kinematic diagram in FIG. 3 of the embodiment of the present invention. It is a well-known circuit schematic diagram.

Explanation of reference numerals

1 Storage Device 10 Controller 102 Microprocessor 104 System Interface 106 Memory Interface 108 Data Compression / Decompression Module 1082 Data Compression Circuits 1083a-n Operation Method Descriptor 1083a First Operation Method Descriptor 1083b Second Operation Method Descriptor 1083n Nth Operation Method Descriptor 1084a- n parameter list 1084a first parameter list 1084b second parameter list 1084n Nth parameter list 1085 data decompression circuit 110 first data buffer 120 second data buffer 20 solid state storage medium 2 external system end 4 data recording block 42 data recording area First compressed data, second compressed data Lumpur information recording area 441 status flag 442 error correction code 443 logic address record 444 holding space first set index (1, 2)
Second group index (1, 2)
A storage device A1 controller A11 system interface A12 microprocessor A13 memory interface A14 data buffer A2 storage medium

Claims (5)

The storage device comprises a controller, at least one solid state storage medium,
The controller includes a system interface connected to a system end previously installed outside, a microprocessor for processing system commands, a memory interface capable of exchanging data with the solid state storage medium,
A microprocessor electrically connected between the system interface and the memory interface is provided, and a data compression circuit and a plurality of algorithm descriptors and a data compression / decompression module for a parameter list used in combination with the data compression circuit are provided. Yes,
The microprocessor reads the type of the original data transmitted by the system interface, and selects an optimal combination of compression functions for the type of the original data from the array combination of the algorithm descriptor and the parameter list. Compresses the original data based on the optimal compression combination to form reduced data having a minimum storage unit, and converts the reduced data having the minimum storage unit into the solid state storage medium through transmission of the memory interface. Storage device with the best compression management mechanism, characterized in that it is recorded and stored in a storage device. 2. The storage device with the best compression management mechanism according to claim 1, wherein the solid state storage medium stores an optimal operation descriptor corresponding to the reduced data and an index index of a parameter list. The data compression / decompression module includes a data decompression circuit, which reads the index index from the solid-state storage medium through the microprocessor, thereby calculating the index data indicating the corresponding reduced data to be stored. 3. The storage device with the best compression management mechanism according to claim 2, wherein the original data is decompressed based on the modulus descriptor and the parameter list. The best compression management mechanism according to claim 1, wherein the storage device comprises a first data buffer, the first data buffer being electrically connected to a system interface, a microprocessor, and a data compression / decompression module. Equipped storage device. The best compression management mechanism according to claim 1, further comprising a second data buffer in the controller, the second data buffer being electrically connected to a memory interface, a microprocessor, and a data compression / decompression module. Storage device equipped with

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