HK1113221B - Recording and/or reproducing apparatus - Google Patents

Description

Recording and/or reproducing apparatus

The present application is a divisional application of an invention patent application having an application date of 2004-3/4, application No. 200480000940.5 entitled "method and apparatus for preserving a data recording status of a write-once recording medium and a write-once recording medium therefor".

Technical Field

The present invention relates to a write-once recording medium that maintains a data recording status of the write-once recording medium, a method of maintaining a data recording status of the write-once recording medium, a medium including computer readable code for the same, and a recording and/or reproducing apparatus for the write-once recording medium.

Background

A recording medium, such as an optical disc, has a data readable area composed of a lead-in area, a lead-out area, and a data area, each of which is composed of clusters. A cluster is a unit of recording or reproducing data. The data cluster is recorded in one of the three areas depending on the data type and the type of standardized recording method.

After data recording, a bitmap is generated to represent information on all areas in which data has been recorded, and then the bitmap is recorded in a predetermined area of a recording medium to facilitate convenient recording and/or reproducing of data. More specifically, a bitmap is generated to represent occupied clusters and unoccupied clusters of each of the lead-in area, the lead-out area, and the data area. The bitmap is recorded in the recording medium so that the recording and/or reproducing apparatus can perform quick access to a desired area of the recording medium. In particular, since bitmaps identify areas of occupied data, they are very useful for write-once recording media in which management of defects generated during data recording is important.

The finalized write once recording medium indicates that the write once recording medium is in a state where no more data can be recorded to the recording medium. The finalization of the write-once recording medium may be either in which the write-once recording medium is finalized although additional data may be recorded in the user data area of the write-once recording medium, or in which the write-once recording medium is finalized when it reaches a predetermined finalization condition, for example, when no more data can be recorded on the write-once recording medium because the user data area of the write-once recording medium is fully occupied with data.

When the write-once recording medium is finalized, it is necessary to save the current data recording state or to prevent a change in the data recording state. Generally, when backup data or an image taken with a monitoring camera is recorded on a write-once medium, important measures must be taken to prevent a third person from forging or changing the recorded data of the recording medium. Even if the recorded data is changed by a third party, it is necessary to recognize the change in the recorded data and to determine the original data recorded on the one-time recording medium.

Disclosure of Invention

The present invention provides a write-once recording medium that maintains a data recording status of the recording medium, a method of maintaining the data recording status of the write-once recording medium, a medium including computer readable code for the same, and a recording and/or reproducing apparatus by which the data recording status of a write-once recording medium that has been finalized is maintained or modification of the data recording status of the write-once recording medium that has been finalized is prevented. It is easy to determine a change in the data recording state of the finalized recording medium, and it is possible to determine original data corresponding to a previous recording state recorded in the write-once recording medium.

Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

To achieve the above and/or other aspects and advantages, embodiments of the present invention provide a method of preserving a data recording status of a recording medium, including: recording data on the recording medium; generating recording status data indicating occupied areas of the recording medium and recording the recording status data in a temporary defect management area allocated in the recording medium; receiving a finalization command for saving data recording status data of the recording medium; and recording predetermined data in the temporary defect management area in response to the finalization command to prevent further recording of data on the recording medium.

The recording of the predetermined data may further include: in response to the finalization command, temporary management data including recording status data finally recorded in the temporary defect management area is copied, and the copied temporary management data is recorded in a defect management area on the recording medium.

The method may further include preventing further recording of the data by determining whether the recording medium has been finalized based on the defect management area containing the copied temporary management data, and preventing further recording of the data by determining whether the recording medium has been finalized based on the defect management area containing the copied temporary management data. Further, the predetermined data may be recorded in the entire unoccupied area of the temporary defect management area.

Further, the recording-status data may further include a bitmap that distinguishes an occupied area of the recording medium and an unoccupied area of the recording medium among the entire data-recordable area on the recording medium by representing the occupied and/or unoccupied areas with different values in the bitmap. Each bitmap may indicate whether data has been recorded in a respective cluster of the recording medium as a data recording unit of the recording medium. The recording medium may also be a write-once recording medium.

To achieve the above and/or other aspects and advantages, embodiments of the present invention provide a method of recording data on a recording medium, including: determining whether the recording medium has been finalized based on the detected finalization flag recorded in the space bitmap of the recording medium; and preventing recording of data to the recording medium based on the determination that the recording medium has been finalized.

To further achieve the above and/or other aspects and advantages, an embodiment of the present invention provides a method of recording data on a recording medium, including: recording of data to the recording medium is prevented based on a determination that predetermined data previously recorded to the recording medium is recorded in the temporary defect management area in response to a finalization command to prevent further recording of data to the recording medium.

Also, to achieve the above and/or other aspects and advantages, an embodiment of the present invention provides a method of recording data on a recording medium, including: determining whether the recording medium has been finalized based on a detected finalization flag recorded in a Defect Management Area (DMA) of the recording medium; and preventing recording of data to the recording medium based on the determination that the recording medium has been finalized.

To achieve the above and/or other aspects and advantages, embodiments of the present invention provide a method of recording data on a recording medium, including: recording of data to the recording medium is prevented based on a recorded Temporary Disc Defect Structure (TDDS), a temporary disc defect list (TDFL), or a Space Bit Map (SBM) recorded in a Defect Management Area (DMA) that does not include the finalization flag and indicating that the recording medium has been finalized. The TDDS, TDFL, and SBM may also be recorded in a Temporary Defect Management Area (TDMA) separate from the DMA. The TDDS and SBM may also be stored in a single area separate from the area including the TDFL.

To achieve the above and/or other aspects and advantages, embodiments of the present invention provide a recording and/or reproducing apparatus including: a pickup which writes data to or reads data from a recording medium; and a controller which controls the pickup to record data on the recording medium, generates recording status data indicating occupied areas in an entire data recordable area on the recording medium, and controls the pickup to record the recording status data in a temporary defect management area allocated on the recording medium and record predetermined data in the temporary defect management area in response to a finalization command issued to save a data recording status of the recording medium to prevent further recording of data on the recording medium.

To achieve the above and/or other aspects and advantages, embodiments of the present invention provide a recording and/or reproducing apparatus including: a pickup which writes data to or reads data from a recording medium; and a controller which controls the pickup to record data on the recording medium and prevents recording of data to the recording medium based on a determination that the temporary defect management area of the recording medium contains predetermined data identifying that the recording medium has been finalized. It may be determined that predetermined data is recorded in the temporary defect management area based on pre-designated data recorded in the entire unoccupied area of the temporary defect management area.

To achieve the above and/or other aspects and advantages, embodiments of the present invention provide a recording medium having a lead-in area, a data area, and a lead-out area, including: a temporary defect management area formed in at least one of the lead-in area, the data area, and the lead-out area, wherein recording status data identifying occupied areas of the recording medium is recorded in the temporary defect management area, wherein if the recording medium has been finalized, predetermined data is recorded in the temporary defect management area to prevent data from being further recorded on the recording medium.

To achieve the above and/or other aspects and advantages, embodiments of the present invention provide a medium including a computer-readable code that controls a controller of a recording and/or reproducing apparatus to perform a method of an embodiment of the present invention.

Similarly, to achieve the above and/or other aspects and advantages, embodiments of the present invention provide a medium including a computer-readable code that controls a controller of the recording and/or reproducing apparatus of an embodiment of the present invention.

Drawings

Fig. 1A and 1B illustrate a structure of a write-once recording medium according to an embodiment of the present invention;

fig. 2 illustrates a structure of recording status data according to an embodiment of the present invention;

fig. 3 illustrates a structure of final recording-status data according to an embodiment of the present invention;

fig. 4 illustrates a detailed data structure of a write-once recording medium having a single recording layer according to an embodiment of the present invention;

fig. 5 illustrates a detailed structure of a temporary recording medium defect structure (TDDS) illustrated in fig. 4 according to another embodiment of the present invention;

fig. 6 illustrates another detailed data structure of a write-once recording medium having a single recording layer according to an embodiment of the present invention;

fig. 7 illustrates a detailed structure of an area for storing the TDDS and the Space Bit Map (SBM) of fig. 6 according to an embodiment of the present invention.

Fig. 8 illustrates another detailed data structure of a write-once recording medium having a single recording layer according to an embodiment of the present invention;

fig. 9 is a block diagram of an apparatus for implementing saving of a data recording status of a write once recording medium according to an embodiment of the present invention;

fig. 10 is a block diagram of the recording and/or reproducing apparatus of fig. 9;

fig. 11 is a flowchart illustrating a method for preserving a data recording status of a write once recording medium according to an embodiment of the present invention; and

fig. 12 is a flowchart illustrating a method for preserving a data recording status of a write once recording medium according to another embodiment of the present invention.

Detailed Description

Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures.

Fig. 1 illustrates a structure of a write-once recording medium according to an embodiment of the present invention. As shown in fig. 1A, if the write-once recording medium has a single recording layer L0, it includes a lead-in area, a data area, and a lead-out area. The lead-in area is located near an inner boundary of the primary recording medium, and the lead-out area is located near an outer boundary of the primary recording medium. The data area is formed between the lead-in and lead-out areas and is divided into a spare area and a user data area.

The user data area indicates an area in which data is recorded. The spare area indicates a recordable space for replacing a defect in the user area. Since it is generally preferable that a one-time recording medium provides the maximum capacity for recording data, however, in consideration of defects, the spare area may be initially set to about 5% of the entire data capacity of the recording medium.

As shown in fig. 1B, if the write-once recording medium has two recording layers L0 and L1, the recording layer L0 has a lead-in area, a data area, and an outer area formed in this order from an inner boundary to an outer boundary of the recording medium. The recording layer L1 also has an outer area, a data area, and a lead-out area formed in this order from the outer boundary to the inner boundary of the recording medium. Compared to the single recording layer write-once medium of fig. 1A, the lead-out area of the double-sided recording medium is formed near the inner boundary of the recording medium.

In other words, the dual recording layer write-once recording medium of fig. 1B records data in an inverse track path (OTP) from a lead-in area of the recording layer L0 to an outer area thereof and then from an outer area of the recording layer L1 to a lead-out area thereof, with a spare area being allocated in each of the recording layers L0 and L1.

In the embodiment of fig. 1A and 1B, spare areas may exist between the lead-in area and the user area and between the outer area and the user area. However, in some cases, the spare area may also be formed in an additional area obtained by dividing the user area, so that at least one spare area may exist between the lead-in area and the lead-out area. Thus, there may be multiple spare areas with various potentially dynamic locations.

The "recording state" data refers to information indicating the recording state of the entire data recordable area on the recording medium by distinguishing occupied areas from unoccupied areas. In particular, information generated by allocating different bit values to occupied and unoccupied clusters is called a bitmap, a cluster is a unit in which data is recorded, and a cluster may also be called a block.

Fig. 2 illustrates a structure of recording status data according to an embodiment of the present invention. As shown in fig. 2. The Space Bit Map (SBM) from SBM #0 to SBM # n represents recording status data.

The SBM # i (i is an integer between 0 and n) includes an identifier of each SBM (e.g., SBM # i), header data, and bitmap data (e.g., bitmap # i). The header data includes a finalization flag and an update counter, and the bitmap data indicates whether data has been recorded on the recordable area of the write-once recording medium in cluster units.

If the recording status data is changed due to the recording of additional data in the recording medium, it is necessary to generate and record an SBM # i including new bitmap data representing occupied data areas. When a new SBM # i is generated and recorded, an update counter included in the new SBM # i indicates the number of updates of the recording status data.

The time at which each SBM # i is generated in order to update the recording status data may be different according to a program installed in the recording and/or reproducing apparatus. However, in general, a new SBM # i will be generated and recorded at least once before a write-once recording medium on which data has been recorded is ejected from the recording and/or reproducing apparatus.

The finalization flag is also used to indicate whether the write-once recording medium has been finalized.

Fig. 3 illustrates a final recording-status data structure according to an embodiment of the present invention. Before the write-once recording medium is finalized, a finalization flag included in a header area of each SBM is denoted as "0" and recorded together with other data. As shown in fig. 3, the SBM recorded before finalization of the occupied area is represented by SBM # n. If a finalization command is issued to the recording and/or reproducing apparatus by a host such as a computer host, only the finalization flag value is changed from "0" to "1" in the data of the last updated SBM # n, and the SBM # n including the finalization flag "1" is recorded again to indicate that the recording medium has been finalized.

As shown in fig. 3, in some cases, predetermined data, for example, "ffh", is recorded in the next area of the SBM # n having the finalization flag "1", thereby preventing the SBM and additional data from being also recorded on the write-once recording medium. In this case, "ffh" is preferably recorded on the entire unoccupied portion of the area for recording the SBM.

Since the SBM having the finalization flag "1" is recorded, the user can save the data recording state of the write-once recording medium at the time of finalization. In other words, even when data recorded on the recording medium that has been finalized is changed, or new data is added to the recorded data, the data that has been recorded before the finalization can be identified by referring to the bitmap data included in the SMB having the finalization flag "1". This allows identification of further data recorded after finalization.

Since predetermined data is recorded in the next area of the SBM # n having the finalization flag "1", the SBM may not be recorded any more to prevent additional data from being recorded on the write-once recording medium that has been finalized.

Although the finalization flag in the embodiments in fig. 2 and 3 is recorded in the header area of each SBM # i, the location of the finalization flag is not limited to the present invention. The finalization flag may be recorded in an area other than the header area of each SBM # i.

The area for recording the finalization flag will be described in detail below with reference to the accompanying drawings. Fig. 4 illustrates an embodiment of a detailed data structure of a write-once recording medium having a single recording layer according to an embodiment of the present invention. Referring to fig. 4, the lead-in area includes a Temporary Disc Defect Structure (TDDS) area, a temporary defect list (TDFL) area, and an SBM area.

In general, a Defect Management Area (DMA) storing information regarding defects generated when data is recorded in a data area is formed in a lead-in area and/or a lead-out area. When the recording medium is loaded into the recording and/or reproducing apparatus, the recording and/or reproducing apparatus performs initialization. The initialization operation includes determining how to manage the write once recording medium and how to record data on the recording medium or reproduce data on the recording medium by reading data including defect data from the lead-in area and/or the lead-out area.

Therefore, as the amount of data recorded in the lead-in area and/or the lead-out area increases, the time required for initialization after the loading of the recording medium increases. In order to reduce the time required for initialization, temporary management data including a TDDS and a TDFL recorded in a Temporary Defect Management Area (TDMA) separate from the DMA of the lead-in area and/or the lead-out area is used.

The TDFL includes data identifying a defective area and data identifying an area that has been recently replaced. The TDDS is used to manage the TDFL and includes data identifying the recording position of the TDFL.

The temporary defect management data also includes an SBM representing recording status data.

In other words, the TDMA is provided to store the TDDS, TDFL, and SBM. In this case, the TDMA is formed in at least one of the lead-in area, the data area, and the lead-out area, and may be physically one area or divided into a plurality of areas.

For example, referring to fig. 4, the lead-in area includes a TDDS area, a TDFL area, and an SBM area. In this case, the TDMA is divided into a TDDS area, a TDFL area and an SBM area. As shown in fig. 6, the lead-in area may include both an area for storing the TDDS and the SBM (i.e., TDDS + SBM area) and an area for storing the TDFL. In this case, the TDMA is divided into two areas,

when the write once recording medium is finalized, the latest recorded TDFL and TDDS are moved to the DMA and finally recorded in the DMA because no more data needs to be recorded on the recording medium or because no more data can be recorded thereon. Therefore, when the recording and/or reproducing apparatus reads the defect management information from the write once recording medium, only meaningful data will be read from the DMA. Therefore, fast initialization can be achieved. In addition, since the same defect management data can be recorded in many areas, the reliability of data can be improved.

The lead-in area includes an SBM area representing recording status data including bitmap data regarding an area in which data has been recorded.

The data area includes spare areas 1 and 2, and a user area. In the embodiment shown in fig. 4, if defect management is selected to be performed by the recording and/or reproducing apparatus, the spare area 1 is allocated at the head of the data area and the spare area 2 is allocated at the end of the data area.

As described above, the lead-in area of the write-once recording medium shown in FIG. 4 includes a TDDS area, a TDFL area, and an SBM area storing an SBM. According to an embodiment of the present invention, in the data structure of the write once recording medium of fig. 4, a finalization flag may be recorded in the TDDS area.

Fig. 5 shows a data structure of the TDDS area shown in fig. 4. As shown in fig. 5, the TDDS area is composed of a plurality of clusters. A cluster is a data recording unit and is composed of a predetermined number of sectors. One cluster stores one TDDS # k (k is an integer equal to or greater than 0). A sector is a basic physical unit of a write-once recording medium.

As shown in fig. 5, the TDDS # k includes a TDDS identifier, a counter representing the number of times the TDDS is updated, a first physical sector number of the drive and write-once disc information area, a first physical sector number in which a possible TDFL corresponding to the TDDS # k has been recorded, the sizes of spare areas 1 and 2, a finalization flag, and data regarding an SBM pointer pointing to the location of an SBM corresponding to the case of the finalized recording medium.

Meanwhile, if the user does not want to perform defect management by the recording and/or reproducing apparatus, the spare area is not allocated accordingly, and the sizes of the spare areas 1 and 2 are recorded as "0".

Fig. 6 illustrates another embodiment of a data structure of a write once recording medium having a single recording layer. As shown in fig. 6, the lead-in area includes a TDFL area and an area for both TDDS and SBM (i.e., TDDS + SBM area). The lead-in area of the write once recording medium shown in fig. 4 stores the TDFL, the TDDS, and the SBM in different areas, while the lead-in area of the write once recording medium of fig. 6 stores the TDDS and the SBM in one cluster of a single area. The TDDS + SBM area and the TDFL area constitute a TDMA.

Fig. 7 illustrates a detailed structure of the TDDS + SBM area of fig. 6. The TDDS and the SBM are recorded in one cluster. The TDDS includes a finalization flag, and the SBM includes a bitmap corresponding to the finalization flag.

As described above, the finalization flag may be recorded not only in the header area of the SBM # i, but also in various areas such as the TDDS area and the TDDS + SBM area.

As shown in fig. 1, the SBM area is preferably formed in at least one of the data area, the lead-in area, and the lead-out area. The SBM area is used to store SBM # i representing recording status data.

As described in detail in the above embodiments, the additional finalization flag is used to save the data recording state of the write-once recording medium. Hereinafter, a method of preserving a data recording state of a write-once recording medium without using a finalization flag will be described with reference to fig. 8 and 9.

Fig. 8 illustrates another embodiment of a data structure of a write-once recording medium having a single recording layer. As shown in fig. 8, the lead-in area of the write-once recording medium includes a TDMA for storing the TDFL, the TDDS, and the SBM. The lead-in area further includes a DMA1 and a DMA2 for storing defect management data. The lead-out area of the write once recording medium includes a DMA3 and a DMA 4.

The TDDS and SBM area are recorded in one cluster of the TDMA and the TDFL is recorded in another cluster. Although the data structure in which both the TDDS and the SBM are recorded in one cluster is similar to that shown in FIG. 7, the finalization flag is not recorded.

When the write once recording medium of FIG. 8 is finalized, the TDDS, SBM, and TDFL that were most recently recorded in the TDMA are copied and recorded in the DMA. Since the final SBM and the final TDDS, and the final TDFL, are copied and recorded in the DMA, no finalization flag needs to be recorded to represent the final SBM recorded in the TDMA.

The unoccupied area of the TDMA is entirely filled with predetermined data, e.g., "ffh", to prevent data from being recorded on the write-once recording medium as well. If the TDMA is filled with data such as 'ffh' or the DMA stores defect management data, the recording and/or reproducing apparatus does not perform recording of data even when the recording and/or reproducing apparatus receives a command for recording additional data after finalizing the write-once recording medium.

Fig. 9 is a block diagram of an apparatus to enable preservation of a data recording status of a write once recording medium according to an embodiment of the present invention. As shown in fig. 9, the apparatus includes a writer/reader 1, a controller 2, and a memory 3.

The writer/reader 1 writes data to the write-once recording medium 100 under the control of the controller 2, and reads the written data to verify the data.

According to an embodiment of the present invention, the controller 2 performs defect management by using a TDMA included in the write once recording medium 100 when recording data on the write once recording medium 100, and also saves a data recording state of the write once recording medium 100.

The saving of the data recording state of the write-once recording medium 100 can be achieved in two ways, i.e., the above-described method using the finalization flag and the above-described method not using the finalization flag.

In the method of using the finalization flag, when the write-once recording medium 100 is finalized, the controller 2 generates and records the finalization flag in a predetermined area of the write-once recording medium 100. More specifically, referring to fig. 3, in the data of the last updated SBM # n, only the value of the finalization flag is changed from "0" to "1", and the SBM # n having the finalization flag "1" is again recorded in the next area of the location of the original SBM # n having the finalization flag "0". The controller 2 may control the writer/reader 1 so as to fill up an empty area having a finalization flag "1" following the SBM # n with predetermined data, i.e., "ffh". The controller 2 then controls the final recording of the TDDS and TDFL so that they are copied and recorded in the DMA. The SBM of the final recording is not required to be copied and recorded in the DMA, and the SBM having the final determination flag "1" recorded in the TDMA is used as the SBM of the final recording.

In the method of not using the finalization flag, when the controller 2 receives a command to finalize the write once recording medium 100 from a host (not shown), the controller 2 controls the finally recorded TDDS, the finally recorded SBM, and the finally recorded TDFL so as to be copied and recorded in the DMA. Thereafter, the controller 2 controls the writer/reader 1 so as to fill up the entire unoccupied area of the TDMA with predetermined data, for example, "ffh".

If the TDMA is filled with data such as "ffh" or if the DMA contains defect management data, the controller 2 does not perform recording of data even if it receives a command for recording additional data from the host after finalizing the write once recording medium 100.

The controller 2 follows a verify-after-write method in which recorded data is verified after recording data in predetermined units to find defective data. Accordingly, the controller 2 records data in predetermined units and verifies the recorded data to identify defect data. The controller 2 generates a TDFL and a TDDS indicating an area in which defect data found during verification is stored. The controller 2 stores the TDFL and the TDDS in the memory 3, collects a predetermined amount of the TDFL and the TDDS, and transfers the collected TDFL and TDDS to the TDMA included in the write once recording medium 100.

Although not required, it will be appreciated that the controller 2 may be a computer that performs the method using computer readable code encoded on a computer readable medium or presented on any other medium that supports the same functionality, such as an optical disc, waveguide, carrier wave, or channel. The computer may also be implemented as a chip with firmware or may be a general or special purpose computer programmable to perform the method.

Further, it should be understood that, in order to achieve a recording capacity of several tens of gigabytes, the writer/reader 1 may include a low-wavelength, high-numerical-aperture type unit that can be used to record several tens of gigabytes of data on a write-once recording medium.

Examples of such units include, but are not limited to, units compatible with blu-ray discs and/or units compatible with advanced optical discs (ADO) using 405nm light wavelengths and having a numerical aperture of 0.85. Examples of other write-once recording media include CD-R and DVD-R.

Fig. 10 is another block diagram of the recording and/or reproducing apparatus. As shown in fig. 10, the recording and/or reproducing apparatus includes a pickup 10 serving as a writer/reader 1. The write/record once medium 100 is mounted on the pickup 10. The recording and/or reproducing apparatus includes a PC I/F22, a DSP22, an RFAMP23, a servo 24, and a system controller 25, all of which constitute the controller 2. The memory 3 may be installed in the system controller 25 of the controller 2.

When recording, the PC I/F21 receives a recording command and data to be recorded from a host (not shown). The system controller 25 performs initialization required for recording. The DSP22 performs Error Correction Code (ECC) encoding on data received from the PC I/F21 by adding data such as parity to the received data, and then modulates the ECC-encoded data in a predetermined manner. The RF AMP23 converts data received from the DSP22 into an RF signal. The pickup 10 records the RF signal received from the RF amp23 into the write-once recording medium 100. The servo 24 receives a command required for servo control from the system controller 25 and servo-controls the pickup 10. According to an embodiment of the present invention, the system controller 25 commands the pickup 10 to read data from the write once recording medium 100 or to record predetermined data, such as temporary management data, on the write once recording medium 100 to perform defect management.

Further, when the write once recording medium 100 is finalized in response to a user's command, or when the write once recording medium 100 is finalized because a predetermined finalization condition is satisfied, the system controller 25 instructs the pickup 10 to record temporary defect management data (i.e., TDDS, TDFL, and SBM) finally recorded in the TDMA in the DMA.

When reproducing, the PC 1/F21 receives a reproduction command from a host (not shown). The controller 25 performs initialization required for reproduction. The pickup 10 projects a laser beam toward the write once recording medium 100, receives the laser beam reflected by the write once recording medium 100, and outputs an optical signal. The RF AMP23 converts an optical signal received from the pickup 10 into an RF signal, supplies modulated data derived from the RF signal to the DSP22, and supplies a servo control signal derived from the RF signal to the servo 24. The DSP22 demodulates the modulated data and outputs the data obtained by ECC error correction. The servo 24 receives a servo control signal from the RF AMP23, receives a command required for servo control from the system controller 25, and servo-controls the pickup 10. The PC I/F21 transmits data received from the DSP22 to a host (not shown). When reproducing, the system controller 25 may instruct the pickup 10 to read out information required for defect management. In other words, the system controller 25 can manage the entire system during recording/reproduction.

A method of preserving a data recording state of a write-once recording medium according to an embodiment of the present invention will now be described based on the structure of the recording and/or reproducing apparatus of fig. 10.

Fig. 11 is a flowchart illustrating a method of saving a data recording status of a write once recording medium according to an embodiment of the present invention. In the method of fig. 11, the finalization flag is used to achieve preservation of the data recording state of the write-once recording medium.

First, the write-once recording medium is inserted into a recording and/or reproducing apparatus for recording data, and data is recorded on the write-once recording medium in operation 110. When the write-once recording medium is inserted into the recording and/or reproducing apparatus, the write-once recording medium is initialized. After initialization, the recording and/or reproducing apparatus prepares to record data by identifying the inserted write once recording medium, determining recording power data, defect management data, and other data associated with the write once recording medium. During initialization, the recording and/or reproducing apparatus accesses an area containing an SBM to obtain information on whether a recordable area of a write once recording medium contains recorded data, thereby quickly finding recording power data, defect management data, and other data related to the write once recording medium. The recording and/or reproducing apparatus obtains preparation data for data recording during initialization and transmits the preparation data to a host connected to the recording and/or reproducing apparatus. Thereafter, the recording and/or reproducing apparatus records data on the write-once recording medium in response to a recording command received from the host.

Recording data on the write-once recording medium includes not only recording user data in the data area but also recording data required for temporary defect management regarding defects generated in the recorded data in the TDMA.

In operation 130, when the data recording status of the write once recording medium is changed due to recording of new data, an SBM # i including new bitmap data representing an area containing the new data is generated and recorded in the TDMA. When a new SBM # i is generated and recorded, an update counter indicating the number of updates on the data recording status data is increased by 1.

The time of generating and recording the SBM # i may be different according to a program installed in each recording and/or reproducing apparatus. After a write-once recording medium is inserted into a recording and/or reproducing apparatus and data is recorded on the write-once recording medium, an SBM having a new bitmap may be generated and recorded only once before the write-once recording medium is ejected from the recording and/or reproducing apparatus. However, in the case where the SBM is generated only once, if an emergency, such as a power outage, occurs during the recording of data on the write-once recording medium, the recording of the SBM cannot be completely achieved. Therefore, it is preferable that the SBM with the new bitmap data is generated and recorded during the recording of data on the write-once recording medium.

In operation 150, the recording and/or reproducing apparatus receives a finalization command to finalize the write-once recording medium from the host. Although the finalization command may be issued arbitrarily by the user, it is generally issued when a predetermined finalization condition is satisfied, for example, when the data area or the TDMA is full of data and thus data cannot be recorded any more. When a predetermined finalization condition is satisfied, the recording and/or reproducing apparatus may automatically finalize the write-once recording medium without receiving a finalization command from the host. However, it is preferable that the recording and/or reproducing apparatus notifies the host that a predetermined finalization condition has been satisfied, and the host asks the user whether the write-once recording medium is to be finalized.

The write once recording medium may include a TDMA to properly manage defects. However, rewritable recording media contain only DMAs and no TDMAs. Therefore, when a rewritable recording and/or reproducing apparatus attempts to record data on a write-once recording medium or reproduce data on a write-once recording medium, compatibility problems may occur. To solve the compatibility problem, the TDDS and TDFL, which have been finally recorded in the TDMA when the write once recording medium is finally determined, are copied and recorded in the DMA in operation 160.

In response to the finalization command, the recording and/or reproducing apparatus generates and records a finalization mark in a predetermined area in operation 170. More specifically, in the data in the SBM # n finally updated, the value of the final determination flag changes from 0 to 1, while the bitmap # n indicating the occupied area remains unchanged. The SMB # n including the final determination flag "1" is recorded again in the next position of the finally updated position of the SBM # n.

Although the finalization flag is recorded in the header area of the SMB # i in the above-described embodiment, the position of the finalization flag is not limited to the embodiment of the present invention. As described above, the finalization flag may be recorded in an area other than the header area of the SMB # i.

In operation 190, in order to prevent additional data from being recorded, predetermined data is recorded in a region next to the region of the SMB # n having the final decision flag "1". For example, "ffh" is recorded to prevent the SBM from being further recorded, and to prevent additional data from being recorded on the write-once recording medium.

Fig. 12 is a flowchart illustrating a method of saving a data recording status of a write once recording medium according to an embodiment of the present invention. In the method of fig. 12, saving the data recording state of the write once recording medium is achieved without using the finalization flag.

First, the write-once recording medium is inserted into a recording and/or reproducing apparatus for recording data, and data is recorded on the write-once recording medium in operation 310.

In operation 330, when the data recording status of the write-once recording medium is changed due to recording of new data, an SBM # i including new bitmap data representing an area containing the new data is generated and recorded in the TDMA.

In operation 350, the recording and/or reproducing apparatus receives a finalization command from the host to finalize the write-once recording medium.

In operation 370, the TDDS and the TDFL, which have been finally recorded in the TDMA, are copied and recorded in the DMA.

In operation 390, in order to prevent additional data from being recorded, predetermined data is recorded in the TDMA. For example, an unoccupied area in the TDMA is filled with "ffh" to prevent additional data from being recorded on the write-once recording medium. Since the final SBM, the final TDDS, and the final TDFL are all copied and recorded in the DMA at the time of finalization, it is not necessary to record a finalization flag to indicate the final SBM recorded in the TDMA. If the TDMA is filled with data such as "ffh" or the DMA contains defect management data, the recording and/or reproducing apparatus does not perform recording of data even when the recording and/or reproducing apparatus receives a command for recording additional data from the host after finalizing the write-once recording medium.

Although the method is described in terms of a write-once recording medium, it should be understood that the method can be used in the case of a rewritable medium or a medium having both write-once and rewritable portions.

Industrial applicability

As described above, according to the present invention, in a write-once recording medium capable of preserving a data recording state of the recording medium, a method of preserving the data recording state of the write-once recording medium, and a recording and/or reproducing apparatus for preserving the data recording state of the write-once recording medium, the data recording state of the write-once recording medium that has been finalized is preserved or modification of the data recording state of the recording medium that has been finalized is prevented. It is easy to determine the change of the data recording state of the finalized recording medium. Further, original data corresponding to a previous recording state recorded in the write-once recording medium may be determined.

Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.

Claims (6)

1. A recording and/or reproducing apparatus comprising:

a pickup which writes and/or reads data to and/or from the write-once recording medium; and

a controller which controls the pickup to record data on the recording medium, records recording status data indicating occupied areas in a user data area on the recording medium in a temporary defect management area allocated on the recording medium, receives a finalization command, and controls the pickup to record predetermined data in an unoccupied area of the temporary defect management area in response to the finalization command.

2. The recording and/or reproducing apparatus of claim 1, wherein the controller controls the pickup to copy the temporary management data including the recording status data lastly recorded in the temporary management defect area and to record the copied temporary management data in a defect management area allocated on the recording medium, in response to the finalization command.

3. The recording and/or reproducing apparatus of claim 1, wherein if the defect management area of the recording medium contains a copy of temporary management data previously recorded in a temporary defect management area separate from the defect management area, the controller controls the pickup not to record the data on the recording medium any more.

4. The recording and/or reproducing apparatus of claim 1, wherein if the temporary defect management area contains the predetermined data, the controller controls the pickup not to record the data on the recording medium any more by a determination that the recording medium has been finalized.

5. The recording and/or reproducing apparatus of claim 1, wherein the recording-status data comprises a bitmap which distinguishes an occupied data area of a user data area and an unoccupied data area of a user data area of the data recordable area on the recording medium by representing the occupied areas and the unoccupied areas with different values.

6. The recording and/or reproducing apparatus of claim 5, wherein each bitmap indicates whether data has been recorded in a respective cluster as a data recording unit.