KR20060017801A - Handling unwritten areas on a storage medium - Google Patents

Abstract

A recording device has medium interface means (14) for interfacing with a storage medium (11) for recording data on the medium and retrieving data from the medium, and a host interface (15) for communicating with a host (13) via messages according to a protocol (ATA/ATAPI). The messages include a write command for writing data, and a read command for reading data. In existing protocols (MMC-3) unwritten areas are considered to be areas that are not yet formatted, and zero data is to be returned on a read command. The device has an error reporting unit (16) for reporting an error via an error message in the event that during reading an area is detected which is unwritten.

Description

HANDLING UNWRITTEN AREAS ON A STORAGE MEDIUM}

The present invention relates to an apparatus for storing information on a storage medium, comprising: media interface means for interfacing with a storage medium for writing data to and reading data from the storage medium, a write command for writing data according to a protocol; An information storage device comprising host interface means for communicating with a host via a message comprising a read command for reading data.

The present invention also relates to a method for storing information on a storage medium, the method comprising communicating with a host via a message comprising a write command for writing data and a read command for reading data in accordance with a protocol. To a storage method.

The present invention also relates to a method for controlling the device, the method comprising: communicating with the device via a message comprising a write command for writing data and a read command for reading data according to a protocol It is about.

The invention also relates to a computer program product for storing information on a storage medium and controlling a recording device.

Controlling the storage of information on storage media such as optical record carriers via recording devices is an international draft of the DVD system and the International Commission on Information Technology Standards (NCITS), ie Working Draft, T10 / 1363-D, Revision 10g, November 12, 2001, "INFORMATION TECHNOLOGY-SCSI Multimedia Commands- (revision MMC10g, also referred to as MMC-3 in this document)." On the other hand, the recording device has a host interface to communicate with the host, which can be a personal computer or a video recorder application unit. The protocol for communication between interfaces is based on the ATA / ATAPI specification, specifically MMC-3 (see MMC-3). NCITS T13 / 1321D AT Attachment with Packet Interface 5, or X3T13 / 1153D ATA-5 Rev. 17, as defined in chapter 2.1.2), and the protocol of X3T13 / 1153D ATA-5 Rev. 17 For this reason, recording devices are called ATA / ATAPI devices, which are used to record real-time data blocks such as video, for example, under the control of the host system. The application accommodates an application, when specified in MMC-3 (see chapter 5.4.3.13.7), when reading an unformatted area (referred to as an ISD area) by writing on a + RW disc, the drive reads sector data. There is a problem with this requirement: for example, the drive can detect non-recorded areas and black dots such as damaged locations or manufacturing defects. Difficult to do

It is therefore an object of the present invention to provide a system for storing information on a storage medium and enabling efficient processing of non-recorded areas.

According to a first aspect of the present invention, the above object is achieved by the information storage device mentioned at the beginning, which includes error reporting means for reporting an error through an error message when detecting an unrecorded area during reading.

According to a second aspect of the present invention, the above object is achieved by a method for storing information on a storage medium as mentioned at the outset, which method provides an error via an error message when detecting a non-recorded area during reading. Reporting the step.

According to a third aspect of the invention, the object is achieved by a method for controlling the apparatus as mentioned at the beginning, which method comprises the steps of receiving an error message when detecting a non-recorded area during reading; Reporting the unrecorded area to the application.

The effect of this measure is that the device reports an error when the read command needs to read a portion of the storage medium containing the unrecorded area. This does not follow MMC-3 (which requires zero and no error at this point) because an error is reported when reading the ICE. The advantage of this is that the application on the host can recognize unrecorded areas, recover quickly from (unexpected) unrecorded areas, and continue reading as soon as possible.

The present invention is also based on the following recognition. In practice, the record carrier needs to be able to read existing reading and recording devices such as digital versatile disc (DVD) players and DVD + RW recorders. Thus, existing devices require at least a partially formatted state as mentioned in MMC-3 of chapteer 5.4.3.13.3. Thus, due to the partially formatted state, blocks may become unrecorded. However, the inventor further recognized that the block may be unwritten due to a write error in which the final state is very serious (ICE). During a write operation, the block could be skipped due to a write error. The writing application may attempt to read the data on the disk for consistency check. The application can read the (partially unrecorded) area and receive zeros (according to MMC-3 for the unrecorded area). The inventor has noted that the zero point may be user data content. Thus, the application is believed to be all well. Error recovery by the recording apparatus is omitted. If such a disc is read at a later moment (eg in a DVD-ROM drive), a file with an unrecorded area (ICE) will be error prone. This is very serious.

In the MMC command, when the DVD + RW recordable drive issues a read command and requests the transfer of a sector whose read command is ICED (unrecorded), the drive needs to return to the zero point as contents. This behavior can lead to alterations in the behavior of DVD-ROM drives and DVD + RW drives, which can lead to data errors on hosts such as PCs. This is because the reader of the ICED sector does not recognize the ICED sector and there is no way to know the history of that sector. The sector is thought to be written, but may be skipped due to the tracking error of the original writer. The original writer reports an error, and the file containing the error can be properly managed in the file system. When the DVD-ROM drive reads this file, it notifies the application of the error. However, if the DVD + RW drive follows the MMC's specification, it will not notify the application of an error. This can lead to errors in the application and even errors in the data used or recorded by the application, for example on the hard disk drive. An error can occur if the file containing the unrecorded area is an executable file for the host. Execution with an error command will result in unexpected behavior, for example causing a host or application system crash. The advance is to recognize this major drawback of the MMC specification and avoid it by returning an error when reading the ICE.

The proposal for the MMC specification is that the drive expected to write may return to the "already" zero point because the drive will perform a background format and all unwritten blocks will be written soon; It's derived from the idea that data can be created. The proponents of the MMC specification did not consider a situation where an error would result in skipped blocks being skipped. The skipping of the block also occurs due to fingerprints, ie the block is covered with foreign matter before cleaning. If the disk is cleaned, the blocks already covered can be written and read, but these blocks can be part of the error file. Thus, the inventors have recognized that not reporting an error for an unwritten block can be replaced by causing a problem and reporting an error for an unrecorded area.

In one embodiment of the apparatus, the host interface means is arranged to communicate via a message comprising a write command for real time writing of data and a read command for real time reading of data. The advantage of this is that reporting of read errors in the case of real-time data prevents the provision of error data to the user, for example to prevent noise or visual manipulation.

In an embodiment of the apparatus, the error reporting means is arranged to detect the unrecorded area by detecting the reflection state of the recording layer of the storage medium. The advantage of this is that the unrecorded area is easily detected.

Further preferred embodiments of the apparatus and method according to the invention are set forth in the claims which follow.

These and other aspects of the invention will be apparent from and elucidated from the embodiments described in the following description and the accompanying drawings.

1 shows a disk-type storage medium, a recording apparatus and a host system,

2 shows a read command,

3A shows a connector on a drive for interfacing,

3B shows the IDE connector layout.

In the drawings, components corresponding to those already described have the same reference numerals.

1 shows a disk-shaped storage medium, recording apparatus and host system. The storage medium 11, such as an optical disc, constitutes a record carrier for the recording device 12. One example of such a record carrier is DVD + RW. Numerous interfacing functions of recording devices are defined according to predefined standards such as ATA / ATAPI-5. Thus, the recording device can be named an ATA / ATAPI device. On the one hand, the recording device 12 has control circuits generally known from, for example, a media interface such as a read / write head, a positioning servo system and a CD or DVD system to interface with a storage medium such as, for example, a DVD + RW disc. On the other hand, the recording device 12 has a host interface, such as an ATA cable, for example, to communicate with the host, which is a video recorder on the side of a personal computer or application with conventional elements, for example, for input and output of video information. Can be A combination of four elements, a DVD + RW medium, ie an ATA / ATAPI device plus host, can form a consumer DVD + RW video recorder.

In the existing protocol (MMC-3), an unrecorded area is regarded as an unformatted area, and zero data will be returned on a read command. The apparatus includes an error reporting unit 16 for reporting an error via an air message upon detecting an unrecorded area during reading. The error message is conveyed via the host interface 15, for example according to the protocol used for the MMC-3 protocol. In the embodiment, the error reporting unit 16 generates an error message for the area corresponding to the sector upon detecting the unrecorded area. Alternatively, the error message includes a range of unrecorded multiples or sectors.

Background information regarding the recording device and storage medium format can be found in the following references.

[DVD] Standard of ECMA-267, Read Only Disc

[DVD + R] 4.7 GB Basic Format Specification System Description 1.1

[DVD + RW] 4.7 GB Native Format Specification Writable Version 1.2

The following definitions are commonly used in recording systems.

Drive: A unit that interfaces to a recording medium and has, for example, an optical pickup unit, a servo, a data path, a memory flash, and is interfaced to a host, for example using APAPI.

Disc: Can be any of optical discs, such as CDDA, CD-R / RW, CD-ROM, DVDROM, DVD + RW and DVD + R SACD.

ECC: This is the minimum amount of data that can be written to a disc. For DVDs, a complete EFM block of 32 kilobytes of user data.

Sector: The minimum data size that can be addressed in 2048 bytes (in a DVD).

Application: An interfacing active unit in a host that requires storing real-time data on a disc and withdrawing from the disc, arranging structures on the disc, and encoding / decoding a video signal, for example.

Chunk: A block of data to be written consecutively without a connection.

De-iced: The + RW phase change material has two states, amorphous and crystalline. All materials on the new disc have the same state, and this disc is called "iced". The transition occurs by writing to the disk. This affects the reflectivity of the disc and how the disc can be read. If this disk contains a freezing area, the current position of the laser can only be determined via wobble. In the write area, positional information is included in the data.

Off Track: When the laser of the optical pickup unit cannot follow the (wave shaped) grooves on the (recordable) disc, this becomes an off track.

In the following, the medium and the protocol on the host interface 15 or the ATA cable will be described in more detail. Popular ATA cables are described in numerous documents, such as the ATA / ATAPI-5 document. The highest protocol level of the cable is provided on the MMC-3. In the following description, the storage medium 11 is a DVD + RW medium, that is, a recordable digital multi-purpose disc. This medium is described in the DVD + RW Physical Format Specification. Although there are problems with the error report and read commands of the protocol provided in MMC-3, a solution to this problem can be understood by understanding the relationship between the medium and the protocol.

When a DVD + RW disc is manufactured, the recording layer is completely unrecorded. This state is called "ICE". The reason for this is that the unrecorded area is in a high reflection state. If the unrecorded areas are less reflective, these areas cause interference due to the small transition from crystalline to amorphous, which causes variation in the reflected laser beam detected by the device. The unrecorded area is free from interference, so a stable reflective laser beam is obtained. Thus, such an unrecorded area looks like "flat" or "slip" like ice, and the ICE can be detected from the reflection state of the recording layer.

In an embodiment, the error report is based on detecting the unrecorded area by detecting the reflection state of the recording layer of the storage medium.

In an embodiment, the present invention may be performed by executing the "READ 10" or "READ 12" command as shown in MMC-3. Upon executing such a read command, the device detects an unrecorded area from, for example, the reflection state as described above, and transmits an error message through the host interface 15 for the sector or sectors for which the pre-record state is detected. The effect can be examined simply by making a disc with an unrecorded area and observing how the DVD + RW writer responds when reading the ICED area. An example of a read command is the definition of read 12 described in FIG.

2 shows a read command. The read command is specified by a table that defines the function of the many bytes that make up the message to be delivered through the host interface. In the first byte 21, a command code indicating that the message is a read command is defined. In the second byte 22, a command option is defined, and in an additional byte 23, the logical block address of the data to be read is defined. The data transfer length is defined in byte 24. A special mode for real time data is defined by the streaming indicator 25. The read command is described in the MMC-3 as the read command 12 as follows.

The READ 12 command requests the logical unit to pass data to the initiator. The latest data value written to the addressed logical block is returned. When the authentication success flag (ASF) is set to zero, anything read by the initiator in the logical block with the title key present in the sector (only DVD-ROM media) will be blocked. The command will end in a CHECK CONDITION state and the SK / ASC / ASCQ value will be set to ILLEGAL REQUEST / READ OF SCARMBLED SECTOR WITHOUT AUTHENTICATION. The Disable Page Out (DPO) bit is not used by the logic unit and will be set to zero. The zero DPO bit indicates that, if supported, the retention priority field in the cache page determines the priority. All other aspects of the algorithm for performing cache memory replacement processing are vendor specific. Fourth unit access (FUA) 1 bit indicates that the logical unit has access to the medium performing the command. The read command will access a particular logical block from the medium (ie, data is not retrieved directly from the cache). If the cache contains a more recent version of the logical block than the media, the logical block will be written to the media first. The zero FUA bit indicates that the logical unit can satisfy the command by accessing the cache memory. In the case of a read operation, any logical block contained in the cache memory can be passed directly from the cache memory to the initializer. The Delivery Length field specifies the number of adjacent logical blocks to be delivered. Zero propagation length indicates that no logical block is passed. This condition does not take error into account. Other values indicate the number of logical blocks to be passed. One streaming bit specifies that a stream playback operation is used for the command. The zero streaming bit specifies that a conventional READ operation is used for the command. If the streaming bit is set to 1, the cache control mode parameter can be ignored. If the streaming bit is set to 1, the FUA bit is set to zero. If both the streaming bit and the FUA bit are set to 1, the logical unit ends the command in the CHECK CONDITION state, and the SK / ASC / ASCQ value will be set to ILLEGAL REQUEST / INVALID FIELD IN CDB.

Thus, the host interface communicates with the host via a message comprising a write command for writing a series of data blocks and a read command for reading the series of data blocks, according to a protocol (eg, ATA / ATAPI-5). For error reporting, an error message is sent through the host interface when detecting an unwritten area during reading.

3A shows a connector on a drive for interfacing. The back 71 of the drive is shown. The connector on the back of the drive is a 5-in-1 connector. The first connector 72 is a digital output terminal, and the second connector 72 is an analog audio output terminal (4-pin, according to MPC-2 standard). Audio output may not be supported. The master / slave connector 73 is a three position jumper block for CS (cable selection), M (master) and S (slave), and jumper 75 is shown at a predetermined position as the default jumper master select. The fourth connector 76 is a 16-pin ATA-2 dual row flat-cable connector, i.e. a 40-pin shrouded & keyed (pin 20 is removed). A) Flat cable connector. This connector, also called an IDE connector, is used to interface to the host via an ATA cable as described in ATA / ATAPI-5. Finally, the connector 77 is a DC power inlet according to the industry standard 4-pin amphenol. The DC power connector supplies the drive with DC power (+5 volts and +12 volts) to be supplied from an external power source.

Figure 3b shows an IDE connector layout that defines the function of the pins. See ATA / ATAPI-5 for details. The data connector is used to interface to the host system. The master / slave connector 73 is used to install an IDE data cable that depends on an existing personal computer configuration. There are three possible connection possibilities: the device as a slave (jumper on slave), the device as a master (jumper on master default), and the device as a master or slave (jumper on cable select), depending on the configuration of other connecting devices. Nor does any jumper mean cable select.

Although the present invention has been mainly described through embodiments using a DVD + RW optical disc, the present invention is an information storage system for recording in real time a rectangular optical disc, a magneto-optical disc, a high density (Blu-ray) disc or a series of data blocks. It is also suitable for other record carriers.

In this specification, the term 'comprising' does not exclude the presence of elements other than the listed elements or steps, and singular quantity surveys that do not adhere to an element do not exclude that these elements are plural, and the reference signs limit the claims. It should be noted that the present invention may be implemented by hardware and software, and some 'means' or 'units' may be provided by the same item of hardware or software. Moreover, the scope of the present invention is not limited to the present embodiments, and the present invention consists of all the novel features described above or a combination of these features.

Claims (9)

As a device for storing information on a storage medium 11 Media interface means (14) for interfacing with the storage medium (11) for writing data to and reading data from the storage medium; Host interface means 15 which communicates with host 13 via a message comprising a write command for writing data and a read command for reading data according to the protocol; An error reporting means (16) for reporting an error via an error message when detecting an unrecorded area during reading. The method of claim 1, And the host interface means (15) is arranged to communicate via a message comprising a write command for real time recording of data and a read command for real time reading of data. The method of claim 1, The error reporting means (16) is arranged to detect an unrecorded area by detecting a reflection state of a recording layer of the storage medium. The method of claim 1, The error reporting means (16) is arranged to report an error message for the area corresponding to the sector. A method for storing information on a storage medium, the method comprising: -Communicating with the host via a message comprising a write command for writing data and a read command for reading data according to the protocol; -If the unrecorded area is detected during reading, reporting the error via an error message. The method of claim 5, The communication comprises transmitting an error message for an area corresponding to the sector. A method for controlling an apparatus according to claim 1 for storing information on a storage medium, comprising: Communicating with the device via a message comprising a write command for writing data and a read command for reading data according to a protocol; -Receiving an error message when detecting an unrecorded area during reading. The method of claim 7, wherein And the communication comprises communicating via a message comprising a write command for real time recording of data and a read command for real time reading of data. A computer program product operative to store information on a storage medium and to perform a method according to any of claims 5 to 8 to a processor.

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