KR20150022281A - Optical disc drive and driving method thereof - Google Patents

Abstract

An ODD capable of ensuring connectivity or compatibility with a host by providing a file system and device information allowed by the host to a host that is incompatible with the ODD and a method of driving the ODD are described. The ODD or the drive method according to the present invention performs FAT32 conversion on a high capacity optical disk and sets the cluster size to 32 Kbytes (16 Sectors) to increase the access speed to the high capacity optical disk.

Description

[0001] The present invention relates to an optical disc drive and a driving method thereof,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc drive and a method of driving the same, and more particularly, to an optical disc drive having compatibility with various hosts and a driving method thereof.

An optical disc drive (ODD), which is one of optical media devices, is a representative information storage and reproduction device. Typical formats of optical discs are CD (Compact Disc) and DVD (Digital Versatile Disc), and the width of BD (Blue ray Disc) is gradually widening. Most DVD media devices have compatibility with low-density CDs (Compact Discs), and more recently optical media devices with enhanced compatibility with BD have also been introduced.

As a typical AV (Audio-Video, audio-video) apparatus, there is a general-purpose apparatus such as a computer, while a conventional apparatus includes a video reproducing apparatus such as a TV (Television) A portable terminal or a player incorporated in a car or the like.

These AV devices allow for a limited range of connectivity, and thus lack compatibility with various types of media. In addition, recent AV devices have a universal serial bus (USB) host function, so that when a USB storage device (USB memory, MP3 player, external HDD, etc.) is connected, the multimedia contents stored in the device can be reproduced. However, since AV devices generally support only a file allocation table (FAT) file system defined by ISO (International Organization for Standardization) 9293, an optical disk that uses CDFS (Compact Disc File System) or UDF Can not be reproduced.

A technique for solving this compatibility problem has been proposed as a prior art. This technology not only solves the hardware recognition problem between the ODD and the host device, but also deals with the compatibility of the data stored in the optical disk. That is, the data storage format of the optical disk is CDFS or UDF, and the file of such format is converted into a file in a general-purpose format, for example, a FAT format, and is stored in the internal memory of the ODD.

It is desirable to shorten the time required to reproduce the content stored in the optical disk in the AV apparatus or to convert the content into the FAT file system before the compatibility with the ODD by the conversion of the file system. In other words, by having compatibility with the ODD, the change to the FAT file system and the reproduction of the content applied thereto are delayed in order to reproduce the content of the optical disk into the unique file system of the optical disk without any file conversion. Therefore, it is a user's requirement to shorten the time required for the file system conversion and the content reproduction time using the converted file system.

KR 1255339 B KR 1151684 B KR 1137835 B

The present invention provides an optical disk drive and a method of driving the optical disk drive capable of improving the access speed to the content of the optical disk on which the file system is converted.

An optical disc drive according to the present invention comprises:

An information processor for processing information related to an optical disc having a file system of a native format;

An interface for connecting the information processor to a file system of the native format or to an external host supporting a FAT32 file system;

A converting unit for converting the file system of the optical disc into the information of the FAT32 file system, and setting a byte size per cluster to 32 Kb; And

And a buffer memory for storing the FAT32 file system information and storing a start address, a size, and a file type of each file stored in the disk.

A method of driving an optical disc drive according to the present invention includes:

Connecting an ODD for driving an optical disc to a host through an interface built in the ODD; And

The file information including the start address, size, and type information of a file stored in the optical disk is stored in a buffer memory Forming FAT32 file system information requested by the host using the file information; .

According to an embodiment of the present invention, the optical disk is preferably a DVD.

According to another embodiment of the present invention, when the optical disk is a CD, the converting unit converts a file system into a FAT16 system having a byte size of 16 Kb per cluster.

According to another embodiment of the present invention, the interface may provide virtual device information that the host allows when the host is incompatible with the optical disc drive.

According to another embodiment of the present invention, the virtual device information is direct-access block device information including the HDD, and the host recognizes the ODD as a direct access block device I will.

According to another embodiment of the present invention, the interface may be connected to the host in a USB manner.

1 shows an example of connecting an ODD according to an embodiment of the present invention to a television which is a kind of a host.
2 shows a schematic configuration of an ODD according to an embodiment of the present invention.
3 is a conceptual block diagram of a file system converter in accordance with one embodiment.
4 schematically shows the structure of the FAT32 boot record.
FIG. 5 shows the overall configuration of the FAT 32.
6 is a flowchart illustrating a process of determining a size of a cluster in FAT32 conversion according to an embodiment of the present invention.
7 is a diagram for explaining connection and data flow through a USB interface between a host (TV) and a slave (ODD) according to an embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of an ODD and a driving method thereof according to the present invention will be described in detail with reference to the accompanying drawings.

The optical disc described in the embodiments includes all media in the form of a disc in which information is physically recorded. These discs include CD, DVD (DVD-R, DVD-RW, DVD + R, DVD + RW, DVD-RAM) and BD. A typical file system of an optical disc may include CDFS, UDF, and the like. The optical disk may be an ODD having an interface that can be connected to various types of hosts, such as a television receiving an airwave or a wired broadcast, a sound source of a file format such as MP3, MP4, WMA, AVI or the like, Lt; / RTI > Although these optical disks are separate independent entities, they can be interpreted as some elements of the ODD because their essential functions can be exercised by the ODD.

As shown in Figure 1, the ODD 10 is interconnected by an inter cable 30 as a slave device (peripheral) to a host 20 such as a television or multimedia player.

The exchange of information via the inter-cable 30 is performed by the interface of the two devices, and the interface may typically include a USB port. 1.1, 2.0, and 3.0. That is, a USB cable can be used as the interconnection cable 30, so that the ODD 10 and the host 20 can exchange mutual information through the USB protocol. The host 20 to which the external slave device can connect supports a limited range of file systems and file formats, such as electronic frames and the like. A representative file system is FAT, which is applied not only to HDD but also to various types of memory cards such as CF (Compact Flash), SD (Secure Digital), MMC (Multi Media Card) and Memory Stick. In addition, the file formats that the multimedia player permits include MP3, MP4, AVI, and WMA. As a host, there is a general-purpose personal computer (PC) or similar system supporting almost all file systems and file formats, and a host manufactured for a specific purpose, for example, a wireless or wired television, A video player, and the like. Hosts manufactured for specific purposes can not support all file systems, and generally support some of the most widely used file systems, typically the FAT file system. Content used by various kinds of hosts is obtained from an externally contacted slave. For example, a television or multimedia player that supports only a FAT file system can not reproduce content from an optical disk of a CDFS / UDF file system.

In order to solve this problem, a method of registering an ODD as a usable device for a host that can not recognize the ODD as a usable device has been proposed. Also, for a host having compatibility with a proprietary file system of an optical disk, To a recognizable and usable file system. If you need to use ODD's internal memory for file system conversion. If a file system conversion is performed on a file that is not used by a specific host, a large amount of memory is required. In some cases, file system conversion It will not be available on the host. Accordingly, in forming the FAT file system information to be provided to the host, the present invention reduces the memory usage by storing the start address and the size of each file stored in the optical disk and the file type in the buffer memory.

2 is a block diagram of an ODD 10 according to one embodiment of the present invention. The ODD 10 includes an optical pickup 12 that reads or writes information from the optical disk 11. [ The optical pickup 12 includes an optical system such as an objective lens, a laser diode (LD), and a photodetector, and a mechanical system that mechanically supports the optical system and causes focusing and tracking operations as in a general structure. The optical system includes an encoder / decoder and is connected to an information processing unit 13 connected to an interface 15 for connection to an external host, and the mechanical system is connected to the servo unit 14. The information processing unit 13, the servo unit 14, and the interface 15 are controlled by the central control unit 16. The FAT file system information formed according to the present invention is stored in the buffer memory 17, which is accessible at the central control unit 16 and the interface 15.

According to an embodiment, the interface 15 includes a USB port, and thus receives and transmits information with a sound reproducer, a video player, a television or the like, which is a kind of the host 20 by the USB protocol.

At this time, the host 20 reproduces the content provided from the ODD 10 by the built-in content reproduction apparatus. In order to provide the contents, the host 20 such as the ODD 10 and the audio device or the AV device should be in a state in which mutual information exchange is possible through the respective interfaces 15 and 21. In addition, the host 20 must be able to recognize the ODD 10 as an acceptable device and obtain the recognizable file system information from the ODD 10. An acceptable device is a host, for example, a device that is recognizable by the host 20 and accessible to the host 20, and a host 20 and a device connected thereto are interconnected by an instruction set Command set and file system. Inaccessible devices are classified as unknown devices, making it impossible to exchange information with each other. Therefore, when the ODD 10 is connected to the host 20, information must be transmitted by an inquiry (request) of the host 20. If the ODD 10 is to send information to the host 20 from the device side In case of incompatibility, a code relating to information of a command set which is compatible with, for example, a most commonly compatible direct information access medium, such as a hard disc drive (HDD), which is mainly used by a direct-access block device Can be transmitted. This can be done by the converter (or converter) embedded in the interface.

In the USB specification, the ODD is a device class code in the interface descriptor, 08H, belonging to a mass storage, and its subclass code is 02h, which is an MMC-5 (ATAPI) command set .

However, since the device of the subclass 02h to which the MMC instruction set is applied, that is, the ODD is not supported by the host, can not be used. Therefore, a device recognized by the host as a usable device, for example, the most common SBC Class code 06h using the small computer system interface block commands) to the host so that the host can recognize the ODD as a usable device. However, if the device of subclass 02h is supported by the host, 02h is transmitted as it is.

ODD for CD and DVD playback is defined as peripheral code 05h using an MMC instruction set. When the host does not accept such an MMC instruction set, an acceptable instruction set, for example, the most common SBC instruction set 00h " corresponding to a direct access block device such as a magnetic HDD as described above, for example. This method is a kind of fake method for the host to recognize the ODD as the HDD.

After the ODD is made available to the host by the long-term deferral method as described above, when the directory entry information recorded in the optical disk is requested from the host, the ODD is set to be unique to the optical disk Format file system information into a file system of a format recognizable by the host, FAT32 file system information, and transmits the file system information. That is, the ODD internally has the file system information of the CDFS / UDF format, but converts the file system information of the FAT32 format into the file system information of the host. This conversion is performed by a converter or a converter incorporated in the interface.

By doing so, the host can recognize the file information including the address and the like of the contents stored in the optical disk, and thus the access and reproduction of the specific contents become possible.

3 is a conceptual block diagram of a file system converter in accordance with an embodiment of the present invention having the elements described above. The FATB buffer has a type of ring buffer and is a component of the file system converter. The file system converter is a part of the interface 15, and allocates a certain area of the built-in memory 17 to use it. The FATB buffer (first buffer memory) stores the start position, size, and file type of the file stored in the disk when the optical disk is loaded, and can be used as raw data in FAT conversion. The FATT buffer (the second buffer memory) is also allocated a certain area of the memory 17, and the function of the FAT conversion algorithm is applied to organize the FAT entry using the file information from the FATB buffer, Buffer. The FAT generator uses the file information (start address, size, type) of the FATB buffer to create a file allocation table from the offset requested from the host, and stores the file allocation table in FATT. The data stored in the FATT buffer is transmitted to the host through a data transmitter embedded in the interface. According to this structure, FAT generation and transmission operate in parallel in independent blocks, thereby increasing efficiency in FAT generation and transmission.

In the present invention, the FAT 32 file system is applied when the optical disk is a high capacity optical disk, for example, a DVD, and the size of a sector per cluster (Bytes per cluster) in the 13th byte of the boot record in the FAT 32 file system Is set to 16 sectors, that is, 32 Kb. However, if the optical disk is a low-capacity optical disk, for example, a CD, it is originally kept as one sector, that is, 2 Kb. That is, conventionally, one sector (0x01h) is set for both CD and DVD regardless of the capacity of the disk. However, in the present invention, the cluster size is set to 16 sectors (0x10h) in the case of a high capacity optical disc, for example, a DVD. 3 shows a structure of a FAT32 boot record in which 16 sectors (0x800h) are set for the DVD in the 11th to 12th byte fields (0x11h to 0x12h), an optical disk type is set in the 13th byte field (0x12h) 0x1h, and DVD sets 0x10h.

This increases the amount of data that can be read during data access to the DVD, increasing the playback speed by increasing the amount of data that can be taken by a single READ command from the host to 2Kbytes to 32Kbytes.

As described above, according to the present invention, if the cluster size is increased to 32 kb for a high capacity optical disc, the sizes of the areas FAT # 1 and FAT # 2 in which the cluster position information is stored can be reduced. 5 schematically shows the overall structure of FAT32.

Referring to FIG. 5, the MBR (Mater Boot Record) has a boot code area of 446 bytes, four partitions having a size of 16 bytes, and a reserved sector. Overall, FAT32 includes [MBR] + [dPdirehls space] + [PBR] + [reserved space], [FAT # 1] + [FAT # 2] + [cluster] In the present invention, the size of the cluster (Bytes per Cluster) is expanded to 32 Kbytes to reduce the size of FAT # 1 and FAT # 2 in which the cluster location information is stored. The sizes of FAT # 1 and FAT # 2 are determined according to the FAT type. At this time, the larger the cluster size, the smaller the area of FAT # 1 and FAT # 2. By storing the physical information of the optical disk in the FAT # 1 and FAT # 2, the host can directly access the optical disk by the addresses obtained from the FAT # 1 and the FAT # 2.

6 is a flowchart of a FAT conversion method according to an optical disc type according to the present invention.

When loading of the disk into the ODD is started (S61), a FAT32 table is formed by the FAT conversion algorithm (S62). At this time, the low capacity optical disk and the high capacity optical disk are discriminated (S63). As a result of the determination, if the optical disk being loaded is read as a low capacity disk, the size of the cluster (Sector per cluster) is set to 2 Kbytes (1 sector) (S64), and when it is read as a high capacity disk, 32 Kbytes (16 sectors) , And the disk loading is completed (S66).

Thus, according to the present invention, the access speed to a large-capacity optical disk such as a DVD can be improved.

FIG. 7 is a conceptual diagram illustrating a connection through a USB interface between a host (HOST) supporting a file format limited by the method of the present invention and an ODD.

Referring to Figure 7, which shows the approximate flow of the connection and information exchange between the HOST and the ODD, in the first step, the HOST and the ODD are interconnected. At this time, the ODD provides false hardware (H / W) information to the HOST, for example, information on the HDD, which is one of the direct access block devices, as described above. In this case, the host recognizes (authenticates) the ODD as the HDD, so the ODD and the host communicate through the SBC command set. If the host is incompatible with the native file system of the optical disc after HOST-based hardware authentication, the ODD creates a FAT32 file system that the host can use by the method described above. After the FAT file system is created, if HOST requests information about the disk contents, the directory or file information is provided based on the FAT32 file system, and the HOST performs playback of the contents based on the information provided by the ODD do.

In response to a request from the host requesting information such as the MBR (master boot record) stored in the first logical block LBA0 (logical block address 0) while the ODD is connected to the host, the ODD includes the boot sector and the FAT32 format Transfer the BIOS Parameter Block (BPB) to the host. Again, when the host (HOST) requests the directory entry, the ODD sends the FAT32 format directory entry information to the host (HOST). The host having acquired the directory entry information can know the cluster location (address) of 32 Kbytes in size according to the feature of the present invention described above, and can read the file data of the selected format through this address. For the general connection method of the above-mentioned optical disc drive and the FAT32 conversion method, reference is made to the patent literature described in the prior art document.

The above description relates to a typical FAT file system recognition and operation process, and conversion from the CDFS / UDF format to the FAT format is performed in real time at the conversion unit by the request of the host.

The apparatus and method of the embodiments described above may be used in cases where the ODD does not allow access, or does not support the native file system of the ODD. That is, when ODD is incompatible with a particular host among various hosts, for example, a multimedia player, it can be used. In addition, according to the present invention, the data access rate is improved by increasing the size of the sector per cluster used in converting the specific file system information recorded on the optical disk into the general purpose FAT32 file system.

Various exemplary embodiments of the present invention have been described and shown in the accompanying drawings. However, it should be understood that these embodiments are only a part of various embodiments. Since various other modifications could occur to those of ordinary skill in the art.

Claims (14)

An information processor for processing information related to an optical disc having a file system of a native format;
An interface for connecting the information processor to a file system of the native format or to an external host supporting a FAT32 file system;
A converting unit for converting the file system of the optical disc into the information of the FAT32 file system, and setting a byte size per cluster to 32 Kb; And
And a buffer memory for storing the FAT32 file system information and storing a start address, a size, and a file type of each file stored in the disk. The method according to claim 1,
Wherein the optical disk is a DVD. 3. The method according to claim 1 or 2,
Wherein when the optical disk is a CD, the converting unit converts the FAT16 system having a byte size of 16 Kb per cluster. The method of claim 3,
Wherein the interface is connected to the host by the virtual device by providing information on a virtual device allowed by the host when the host is incompatible with the optical disk drive. 3. The method according to claim 1 or 2,
Wherein the interface is connected to the host as the virtual device by providing information on the virtual device permitted by the host when the host is incompatible with the optical disk drive. 5. The method of claim 4,
Wherein the virtual device is a direct access block device. 3. The method according to claim 1 or 2,
And the interface connected to the host is a USB system. Connecting an ODD for driving an optical disc to a host through an interface built in the ODD; And
A file system of a unique format of an optical disc is converted into information of a FAT32 file system set to a size of 32 Kbytes per cluster by using a conversion unit provided in the interface, Storing file information including type information in a buffer memory and forming FAT32 file system information requested by a host using the file information; And an optical disc drive. 9. The method of claim 8,
Wherein the optical disk is a DVD. 10. The method according to claim 8 or 9,
Wherein when the optical disk is a CD, the file system of the unique format of the optical disk is converted into a FAT16 system having a byte size of 16 Kb per cluster. 11. The method of claim 10,
Wherein the interface is connected to the host as the virtual device by providing information on a virtual device permitted by the host when the host is incompatible with the optical disk drive Way. 12. The method of claim 11,
Wherein the virtual device is a direct access block device. 10. The method according to claim 8 or 9,
Wherein the interface is connected to the host as the virtual device by providing information on a virtual device permitted by the host when the host is incompatible with the optical disk drive Way. 14. The method of claim 13,
Wherein the virtual device is a direct access block device.

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