KR20030075529A - Method for operating memory in optical disc record/player - Google Patents

Abstract

PURPOSE: A method for operating a memory of an optical disk recorder/reproducer is provided to divide the memory for recording purpose only and reproducing purpose only, and to assign more memory pages to a command having a high probability, thereby reducing unnecessary memory access time to the maximum. CONSTITUTION: A memory is empty in an initial state. If a read command 1(R1) is transmitted from a host, data requested by the read command 1 is read from a disk, and is stored in a page 1. Data of 7 blocks(R2-R7) is pre-read from the disk through a cash operation, and is stored in pages 2 to 7. The data requested by the read command 1 is read from the page 1, and is transmitted to the host. If a transmitted command is a write command 1(W1), the data of the 7 blocks is moved to the page 1 to 6. R7 data existing in the page 7 is moved to the page 6. Data of the write command 1 is stored on the page 7 with the write command 1. The data is not recorded on the disk.

Description

Method for operating memory in optical disc record / player

The present invention relates to a method of operating a memory in an optical disc recorder during recording and reproduction of data.

In general, an optical recording medium, that is, an optical disc recording and reproducing apparatus for recording and reproducing an optical disc, reproduces data recorded on the optical disc using an optical disc such as a compact disc (CD), a digital versatile disc (DVD), or the like as a recording medium. And a device for recording data on the disc.

The DVD is not much different from the CD in terms of implementation. That is, the data is recognized on the same principle as the CD for recognizing the data of 0 and 1 by the difference in the amount of light reflected by the laser. The difference is that the data storage is smaller than the CD.

The host can be connected to the above-described optical disc recording / reproducing apparatus as shown in FIG. Here, the host is a kind of personal computer (PC), in which the optical disc recording and reproducing apparatus is supported by the PC.

The host transmits a read / write command as shown in Figs. 2 and 3 to the optical disc recording and reproducing apparatus, and the optical disc recording and reproducing apparatus is recorded on the optical disc according to the read / write command of the host. Data is reproduced and transmitted to the host, or data transmitted from the host is recorded on the optical disc.

That is, FIG. 2 illustrates an example of a general read command format outputted from the host to the optical disc recording and reproducing apparatus when data is reproduced from the optical disc, and FIG. FIG. 1 shows an example of a write command format output from a host to an optical disk recording / reproducing apparatus.

In this case, the read / write command includes a Logical Block Address (LBA) that specifies a read or write position and a transfer length that informs the size of the data that follows.

For example, when reproducing data recorded on an optical disc, the host generates a read command as shown in FIG. 2 and outputs the read command to the optical disc recording and reproducing apparatus, wherein the optical disc recording and reproducing apparatus seeks the read command through a seek. Data is read from the LBA in the designated optical disc by the transfer length and stored in a memory (not shown) in the optical disc recording and reproducing apparatus. Then, the optical disc recording and reproducing apparatus reads the data stored in the memory and transfers the data back to the host.

On the other hand, when data to be recorded on the optical disc is generated, the host sends the data to be recorded to the optical disc recording and reproducing apparatus together with the write command as shown in FIG. The optical disc recording and reproducing apparatus stores data transmitted from the host in a memory allocated to the optical disc recording and reproducing apparatus, and then seeks and transmits a target recording position (ie, LBA) in the optical disc designated by the write command through seek. Record data by length.

In this manner, data read / write on the optical disc is performed through buffering using memory pages in the optical disc recording / reproducing apparatus.

At this time, the optical disc recording and reproducing apparatus should respond to the command with a minimum time delay when a read or write command is transmitted from the host.

Therefore, in the case of reproducing in order to improve the speed of the optical disc recording / reproducing apparatus, when a read command is inputted, a cache for storing not only the data of the address designated by the current read command but also the data of the next address in advance is stored in the memory. ) To operate. This is because it takes a long time to read the data by the stored length by seeking the corresponding physical address on the disk. Since the seek operation of moving the optical pickup in the optical disc recording and reproducing apparatus is significantly slower than transferring data to the host, the host also reads the data of the next address of the desired address in advance and stores it in the memory. Hereinafter is referred to as cache operation.

Then, when the next read command is input, it checks whether the data of the requested read command and the previously read data match, and then transfers the data in the memory to the host. This process is repeated as long as the read command is continued. This is possible because the probability that the data you want on the host is immediately after the data you wanted before.

On the other hand, writes use an algorithm that collects physically continuous data in memory and writes them to disk at once with one seek.

In other words, in the case of write, it is similar to the cache. In order to overcome the low speed of the optical pickup, the data transmitted with the write command when the write command is executed is not directly written to the disk but is stored in the memory. Informs that it has been processed normally. The host then transmits consecutive data with the next write command because there is a high probability that the physical data on the disk is contiguous with the previously transmitted and stored stochastic data.

In this way, the data of consecutive addresses are stored in the memory, and when the memory is full or discontinuous data is input, when the first physical address is recorded and written on the disk, a large amount of data is stored in one seek. Can be recorded.

However, read and write commands may also be sent alternately from the host. If a read and a write command are alternately generated for one disk, a discontinuity point occurs in the command. Therefore, the memory may cause a significant speed degradation since the buffering for the read and the buffering for the write are performed alternately.

For example, suppose you wanted 1 block of data (ie, 32k bytes) on the host, and the memory is all 10 blocks long. Then, the optical disc recording and reproducing apparatus reads not only one block desired by the host but also 9 blocks of data from the disk in advance through a cache operation and stores them in the memory. At this time, if the next command is a continuous read command (called a cache hit), the data of the next second block may be read from memory and transferred to the host without having to read the data again from the disk. However, if the next command is a write command, the remaining nine blocks of data stored in the memory become useless data. That is, since the data transmitted with the write command are overwritten again from the beginning of the memory, the data of 9 blocks previously read and stored are lost. As a result, the time taken to read nine blocks is lost.

On the other hand, suppose that a write command is transmitted continuously so that two consecutive blocks of data are stored in the memory and no actual recording is performed.

Then, assuming that the next command is a read command, it is necessary to first record the two blocks of previously stored data on the disc. In this case, there is no time loss for the previous two write commands, but since subsequent read commands are performed, data of two blocks stored in the memory must first be recorded on the disc, and then a playback operation may be performed.

The smaller the above-mentioned cases, the less time loss. However, if the read and write commands are transmitted simultaneously or alternately, data that cannot be used in the memory is stored, which is a loss in time. Can take

In this way, if the read command is continuously transmitted or the write command is not transmitted continuously, and the read command and the write command are alternately, that is, a discontinuity occurs in the command, the response speed of the optical recording / reproducing apparatus becomes slow. That is, when a read or write command is received from the host, a delay occurs in response time according to the command, thereby degrading the performance of the optical disc recording / reproducing apparatus.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a memory operating method of an optical disk recording / reproducing apparatus which improves the performance of the optical disk recording / reproducing apparatus by separating and operating the memory for recording and reproduction. Is in.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a general diagram showing a data transfer process between an optical disc recording and reproducing apparatus and a host.

2 illustrates an example of a general read command format.

3 illustrates an example of a general write command format.

4A to 4C show an embodiment of memory operation in the optical recording and reproducing apparatus according to the present invention.

In the memory operating method of the optical disk recording and reproducing apparatus according to the present invention for achieving the above object, the data read from the disk in accordance with the read command transmitted from the host, or the data transmitted with the write command from the host Dividing a memory of an optical disc recording / reproducing player into a recording area and a reproducing area, and if the command transmitted from the host is a read command, check whether the data requested by the read command is stored in the reproducing area, and If it is confirmed that the data is not stored in the playback area, the data requested by the read command is read from the disk, stored from the first playback area of the memory, and the data located after the address designated by the read command is cached in advance. Read from disk And sequentially store the data in the play area, and transmit the data requested by the read command to the host and simultaneously move the data read through the cache operation to an upper direction of the play area. Characterized in that the steps are repeated for a while.

The memory operating method of the optical record player according to the present invention is characterized in that the size of the area for recording and the area for reproduction is varied according to the read / write command.

In the memory operating method of the optical recorder according to the present invention, if the data requested by the read command is already stored in the reproduction area of the memory through a cache operation, the data stored in the memory is transferred to the host and the subsequent cache operation is performed. The data read through is moved to an upper direction of the reproduction area.

In the memory operating method of the optical record player according to the present invention, if the data requested by the read command is not stored in the reproduction area of the memory, the data requested by the read command is read from a disc and stored from the first reproduction area of the memory. At the same time, through the cache operation, data located next to the address designated by the read command is read in advance from the disk and sequentially stored in the reproduction area, and the data requested by the read command is transmitted to the host and simultaneously cached. The data read through the operation may be repeated while moving the read command in an upper direction of the reproduction area while the read command is continued.

A memory operating method of an optical disc recording / reproducing apparatus according to the present invention is an optical disc recording / reproducing apparatus for storing data read from a disc according to a read command transmitted from a host, or storing data transmitted with a write command from a host. The process of dividing a memory into a recording area and a reproduction area, and sequentially storing data transmitted with the write command in the recording area when the command transmitted from the host is a write command, is repeated during the write command. And if the discontinuity occurs in the write command, recording all data sequentially stored in the recording area onto the disc.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The present invention is a method of dividing a memory for recording and reproducing, and allocating a large number of memory pages for commands having a high probability. Therefore, in the best case, for example, when only one of the read command and the write command is transmitted, all the memories can be used only for one purpose, i.e., for reproducing or recording. In the worst case, for example, when a read command and a write command are transmitted with almost similar probability, the memory is divided and used for reproduction and recording. This can reduce unnecessary memory access time as much as possible. This is referred to as internal DMA (Internal Direct Memory Access) in the present invention.

In other words, the internal DMA means that data in the memory can be moved as a whole. For example, data from pages 2 to 7 can be moved to pages 1 to 6 and vice versa. Or, internally, data of a desired location (ie, page) can be accessed. You can also change the order of access.

This requires much less time than the seek operation or the read / write operation on the disc.

4A to 4C are diagrams for explaining an internal DMA process according to the present invention.

Here, it is assumed that the memory has seven pages (2k bytes) for convenience of explanation, and the transmission length designated by one read or write command is one block. In addition, the command transmitted from the host is read command 1 (R1) / write command 1 (W1) / write command 2 (W2) / read command 3 (R3) / read command 8 (R8) / read command 10 (R10) / Assume that the write command 3 (W3) / write command 6 (W6) order. At this time, the memory is divided into a reproduction area and a recording area. Data read from the disc by the read command is stored in the reproduction area, and data transmitted with the write command is stored in the recording area. The size of the reproduction area and the recording area varies depending on the read / write command.

If the read command or the write command is continuous, the data stored in the reproduction area or the recording area is also stored continuously.

That is, referring to FIG. 4A, the memory is empty in the initial state. In this case, it is assumed that the read command 1 R1 is transmitted from the host, and the data requested by the read command 1 R1 is read from the disk and stored in the first position of the memory playback area, that is, the P1 page, and is cached. Data of up to seven blocks (R2 to R7) is read in advance from the disk and stored in pages P2 to P7 of the memory. The read command 1 (R1) then reads the requested data from the P1 page of the memory and sends it to the host.

Subsequently, if the command to be transmitted is the write command 1 (W1), the R2 to R7 data in the P2 to P7 pages are moved to the P1 to 6 pages as a whole through the internal DMA. That is, the R2 data stored in the P2 page moves to the P1 page, the R3 data stored in the P3 page moves to the P2 page, and the R7 data stored in the P7 page moves to the P6 page. The last position of the memory, that is, the P7 page, which is the first position of the recording area, stores the W1 data transmitted with the write command. At this time, the W1 data is not recorded on the disc.

Subsequently, if the command transmitted from the host is a write command 2 (W2) continuously as shown in FIG. 4B, the last cached data, that is, R7 data stored in the P6 page is deleted. This is because the last-cached data has the least importance. The W2 data transmitted together with the write command is stored in the R7 data place, that is, the P6 page. In this case, the W1 and W2 data are stored continuously. If a write command is sent continuously, the data is deleted from memory in the last cached order.

If the command transmitted from the host is a read command R3, the pointer of the memory is moved to transfer the R3 data stored in the P2 page to the host. That is, since the R3 data requested by the read command R3 is already stored in the memory, there is no need to read the R3 data from the disk again.

Then, the data read in the cache, for example, the R4, R5, and R6 data, are moved one page to the reproduction area direction through the internal DMA. That is, the R4 data stored in the P3 page moves to the P2 page, the R5 data stored in the P4 page moves to the P3 page, and the R6 data stored in the P5 page moves to the P4 page. The P5 page then contains no stored data or becomes obsolete data.

At this time, if the command transmitted from the host is a read command for which cached data is not available, for example, read command 8 (R8), the data corresponding to read command 8 (R8) is read from the disc, and the first position of the reproduction area of the memory, namely, At the same time, the data of up to five blocks (R9 to R12) is read in advance from the disk and stored in the P2 to P5 pages of the memory through a cache operation. At this time, the W1 and W2 data transmitted with the write command and stored in the recording area of the memory are kept as they are. That is, the cache operation is performed only before the recording area in which the W1 and W2 data are stored.

Then, as shown in FIG. 4C, the data requested by the read command 8 (R8) is read from the P1 page of the memory and transmitted to the host. Subsequently, the R9 to R12 data in the P2 to P5 pages are moved to the P1 to P4 pages in the reproduction region direction through the internal DMA. That is, the R9 data stored in the P2 page is the P1 page, the R10 data stored in the P3 page is the P2 page, the R11 data stored in the P4 page is the P3 page, and the R12 data stored in the P5 page is Move to P4 page.

If the command transmitted from the host is a read command 10 (R10), the pointer of the memory is moved to read the R10 data stored in the P2 page and transmitted to the host. That is, since the R10 data requested by the read command 10 is already stored in the memory, it is not necessary to read the R10 data from the disk again and store it in the memory.

Then, the data read into the cache by the internal DMA, for example, the R11 and R12 data, is moved one page to the reproduction area direction. That is, the R11 data stored in the P3 page moves to the P2 page, and the R12 data stored in the P4 page moves to the P3 page. The pages P5 and P6 have no data stored or become useless data. At this time, the R9 data in the P1 page is not yet requested by the host and is thus maintained without being deleted or overwritten.

If the command transmitted from the host is the write command 3 (W3), the W3 data transmitted with the write command 3 is stored in the P5 page. In this case, the W1, W2, and W3 data are stored continuously.

Then, if the command transmitted from the host is a discontinuous write command, for example, write command 6 (W6), the W1 to W3 data stored in P7 to P5 are continuously recorded on the disk through one seek. Then, the W6 data transmitted with the write command 6 (W6) from the host is stored in the P7 page.

In the present invention, a method of directly moving data by the internal DMA method has been described as an embodiment, but it may be implemented as a linked list or pointer readjustment.

As described above, according to the memory operating method of the optical disc recorder according to the present invention, by dividing the memory in the optical disc recorder for recording and reproduction, and allocating a large number of memory pages for commands having high probability, Since the access time can be reduced as much as possible, the optical disc recording / reproducing apparatus can respond to the command of the host without time delay even if the read / write commands are alternately transmitted from the host. In particular, by resizing the recording area and the reproduction area according to the read / write command, it is possible to adaptively operate the memory and to prevent the collision between the recording area and the reproduction area.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

Claims (5)

A memory operating method of an optical disc recording / reproducing player having a memory for storing data read from a disc according to a read command transmitted from a host, or storing data transmitted with a write command from a host, Dividing the memory into a recording area and a reproduction area; And If the command transmitted from the host is a read command, check whether the data requested by the read command is stored in the reproduction area. If it is determined that the command is not stored in the reproduction area, the data requested by the read command is read from the disc. At the same time as storing from the first reproduction area of the memory, the data located next to the address designated by the read command is read in advance from the disc and stored sequentially in the reproduction area through a cache operation. And transmitting the data read through the cache operation to the host and repeating the movement of the data to the upper direction of the reproduction area while the read command is continued. operation Way. The method of claim 1, And a size of an area for recording and an area for reproduction is varied according to the read / write command. The method of claim 1, If the data requested by the read command is already stored in the reproduction area of the memory through the cache operation, the data stored in the memory is transferred to the host and the data read through the subsequent cache operation is moved to the upper direction of the reproduction area. And a memory operating method of the optical recorder. A memory operating method of an optical disc recording / reproducing player having a memory for storing data read from a disc in accordance with a read command transmitted from a host, or storing data transmitted with a write command from a host. Dividing the memory into a recording area and a reproduction area; And If the command transmitted from the host is a write command, the process of sequentially storing data transmitted with the write command in the recording area is repeated while the write command is continued, and if the discontinuity occurs in the write command, the write command is sequentially performed. And recording all the stored data on the disc. The method of claim 4, wherein If a discontinuity occurs in the write command, all the data previously stored in the recording area are sequentially recorded on the disk, and the write command continues the process of sequentially storing the data transmitted together with the new write command from the first recording area. Repeating the program and repeating the write command, and if the write command is discontinuous, all of the sequentially stored data are recorded on the disc.