Skip to main content

Full text of "USPTO Patents Application 10670332"

See other formats


(19) 



J 



(12) 



(43) Date of publication: 

14.04.1999 Bulletin 1999/15 



Europaisches Patentamt 
European Patent Office 
Off ice europeen des brevets (11) EP 0 908 882 A2 

EUROPEAN PATENT APPLICATION 

(51) IntCI 6 : G11B 20/18 



(21) Application number: 98117491.5 

(22) Date of filing: 15.09.1998 



(84) Designated Contracting States: 


(72) Inventor: Mine, Norichika 


AT BE CH CY DE DK ES Fl FR GB GR IE IT LI LU 


Shinagawa-ku, Tokyo (JP) 


MCNLPTSE 




Designated Extension States: 


(74) Representative: 


AL LT LV MK RO SI 


Melzer, Wolfgang, Dipl.-lng. et al 




Patentanwalte 


(30) Priority: 16.09.1997 J P 250712/97 


Mitscherlich & Partner, 




Sonnenstrasse 33 


(71) Applicant: SONY CORPORATION 


80331 Munchen (DE) 


Tokyo 141 (JP) 



(54) Recording apparatus, recording method and disc-shaped record medium 



(57) A Writter Block Bit Map WBBM is recorded (8) 
in a lead-in area of a rewritable disc (1). The WBBM is a 
bit map that represents whether each block that is a 
record/reproduction data unit is a recorded block or a 
non-recorded block. A finalizing process for recording 
dummy data in the vicinity of a recorded block is per- 
formed so that a read-only disc drive can seek a block 
and a servo operation of the drive can be stable. At this 
point, with reference to the WBBM, the efficiency of the 



process can be improved. When a plurality of WBBMs 
are ring-structured and the WBBMs are successively 
updated, the write operation can be prevented from 
being concentrated to the same area. In addition, a 
destroyed WBBM due to a power failure or the like can 
be restored. The value of an update counter represents 
the latest WBBM. 



Fig. 1 



CM 
< 

CM 
CO 
CO 

CO 

o 

O) 



J_n_ 



LD 
DRIVE 



RECORDING 
SYSTEM 



AMPLIFYING 



SLED SERVO « 



REPRODUCING 
SYSTEM 



-» j DEC ~| fr. 



CONTROLLER 



SERVO 
SYSTEM 




ROM 




RAM 




? J 

14 


) 

24 


) 

23 



10 

_L 



HOST 
PROC 



LU 



Printed by Xerox (UK) Business Services 
2.16.7/3.6 



1 



EP0 908 882 A2 



2 



Description 

BACKGROUND OF THE INVENTION 

Field of the Invention s 

[0001] The present invention relates to a recording 
apparatus for use with an optical disc or the like, a 
recording method thereof, and a disc-shaped recording 
medium. 

Description of the Related Art 

[0002] Disc-shaped record mediums (for example, 
DVDs) can be categorized as rewritable mediums 
(DVD+RW) and read-only mediums (DVD-ROM) 
depending on their characteristics. Since their physical 
formats are similar, it is preferable to allow a DVD-ROM 
drive to reproduce data from a DVD+RW disc. There are 
difference between the DVD+RW drive and the DVD- 
ROM drive in a spindle servo signal and a method for 
obtaining a position signal (address) of a medium. The 
DVD+RW disc has a wobbling groove. The DVD+RW 
drive obtains a position signal from a reproduced signal 
of the wobbling groove. In contrast, the DVD-ROM disc 
does not have such a wobbling groove. The DVD-ROM 
drive obtains a position signal from a frame synchro- 
nous signal and an address signal reproduced from the 
DVD-ROM disc. 

[0003] To allow the DVD-ROM drive to reproduce data 
from the DVD-RW disc, a frame synchronous signal and 
a position signal are placed in data of the DVD+RW 
disc. However, since the DVD+RW disc has a non- 
recorded portion before or after recorded data, it is diffi- 
cult for the DVD-ROM drive to reproduce data from the 
DVD+RW disc. In reality, since the DVD-ROM drive can- 
not reproduce the frame synchronous signal from the 
DVD+RW disc, the DVD-ROM cannot stably operate the 
spindle servo and perform the seek operation for read- 
ing a desired sector from the DVD+RW disc. 
[0004] The seek operation is performed in a combina- 
tion of a coarse seek operation and a fine seek opera- 
tion. In the coarse servo operation, many tracks are 
jumped at a time. On the other hand, in the fine servo 
operation, a desired sector is acquired in the vicinity of 
a target position. Due to the eccentricity of the disc, 
when the seek operation is performed in the fine servo 
operation, a deviation of several ten tracks to several 
hundred tracks normally takes place. If the jumped posi- 
tion is a non-recorded area, the target track cannot be 
acquired. Thus, when the seek operation is performed, 
data containing a frame synchronous signal and a posi- 
tion signal should have been recorded in the vicinity of 
the target sector. 

[0005] Thus, to allow the DVD-ROM drive to repro- 
duce data from the DVD+RW disc, dummy data should 
have been recorded before or after recorded data on the 
DVD+RW To do that, a process referred to as finalizing 



process is performed. The finalizing process can be 
performed in the following two methods. 
[0006] As the first method, a file system is analyzed. 
Generally, a file system has a space bit map for allocat- 
ing a user area. A UDF system that is often used for 
DVD discs has a space bit map and information that 
represents whether or not each entry of each file has 
been recorded. Thus, when the file system is analyzed, 
a position of user data (namely, a position to which 
dummy data should be written) can be obtained. This 
method is performed by an application program of a 
host computer. 

[0007] As the second method, a blank area is 
detected. In this method, all blocks of the DVD+RW disc 
are read. When a block can be read, it is treated as a 
recorded block. On the other hand, when a block cannot 
be read, the hardware of the drive determines whether 
an RF signal is absent (namely, data has been 
recorded) or data that has been recorded cannot be 
reproduced. When the RF signal cannot be obtained, 
since data has not been recorded, dummy data is 
recorded. Even if the RF signal is obtained, when data 
cannot be read, the drive determines whether the rele- 
vant block is unchanged or dummy data is overwritten 
depending on the amount of an ECC error or the like. 
[0008] The first method (for analyzing a file system for 
use) can be effectively performed as long as the number 
of directories/files is small. However, when the number 
of directories/files is as large as several thousands, it 
takes a long time to perform the process. Thus, this 
method is not effective. In the file system other than the 
UDF system, this method cannot be used because 
available information is limited to allocation information. 
In other words, depending on a file system for use, the 
feasibility of this method is restricted. On the other 
hand, the second method (for detecting a blank area) 
can be used regardless of a file system for use. How- 
ever, since all blocks of the disc should be read, it takes 
a long time to perform the process. 
[0009] Other than the above-described two methods, 
when a disc is formed, a certificating process may be 
required. In the certificating process, a certification pat- 
tern is recorded on the entire disc. By reproducing the 
data, it is determined whether or not there is a defect on 
the disc. Thus, when the certification pattern is recorded 
on the entire surface, since non-recorded areas are 
absent, the finalizing process is not required. However, 
since the storage capacity of the DVD+RW disc is large, 
it takes around one hour to perform the certificating 
process. Thus, since this method is not effective, it is 
improper to require the user to perform the certificating 
process. 

OBJECTS AND SUMMARY OF THE INVENTION 

[001 0] It is therefore an object of the invention to pro- 
vide a recording apparatus that allows the finalizing 
process to be quickly performed regardless of a file sys- 



15 



20 



25 



30 



35 



40 



45 



50 



2 



3 



EP 0 908 882 A2 



4 



tem for use, a recording method thereof, and a disc- 
shaped recording medium thereof. 
[0011] According to a first aspect of the invention, 
there is provided a recording apparatus for use with a 
disc-shaped record medium having a user data area s 
and a management area, comprising: 

recording means for recording at least one bit map 
that represent whether or not each data unit for 
recording/reproducing has been recorded; and 10 
processing means for recording the bit map to the 
management area of the disc-shaped record 
medium, and referencing the bit map and adding a 
predetermined amount of data that contains at least 
one of servo information and position information to is 
a non-recorded area in the vicinity of recorded data 
so as to allow a reproducing apparatus that repro- 
duces data from a read-only disc-shaped medium 
and obtains at least one of the servo information 
and the position information from a reproduced sig- 20 
nal to reproduce data from a rewritable disc-shaped 
record medium. 

[001 2] According to a second aspect of the invention, 
there is provided a recording method for use with a 25 
rewritable disc-shaped record medium having a user 
data area and a management area, comprising the 
steps of: 

creating a bit map composed of bits that represent 30 
whether or not each record/reproduction data unit 
has been recorded; 

recording the bit map to the management area of 
the disc-shaped record medium; and 
referencing the bit map and adding a predeter- 35 
mined amount of data that contains at least one of 
servo information and position information to a non- 
recorded area in the vicinity of recorded data so as 
to allow a reproducing apparatus that reproduces 
data from a read-only disc-shaped medium and 40 
obtains at least one of the servo information and the 
position information from a reproduced signal to 
reproduce data from a rewritable disc-shaped 
record medium. 

45 

[0013] According to a third aspect of the invention, 
there is provided a disc-shaped record medium having 
a first rewritable area for recording user data and a sec- 
ond rewritable area for recording management data, 

50 

wherein at least one of servo information and posi- 
tion information is pre-recorded as wobbling infor- 
mation in a wobbling groove, and 
wherein the second rewritable area has a bit map 
that represents whether or not each data unit for 55 
recording/reproducing for the first rewritable area 
has been recorded. 



[0014] A bit map that is a set of bits representing 
whether or not each block as record/reproduction data 
unit has been recorded is recorded in a management 
area of the disc. Thus, when the finalizing process is 
performed, finalization data (dummy data) can be 
recorded with reference to the bit map. Consequently, 
the finalizing process can be quickly performed regard- 
less of a file system for use. In addition, the user is not 
requested to perform the certifying process. 
[0015] The above, and other, objects, features and 
advantage of the present invention will become readily 
apparent from the following detailed description thereof 
which is to be read in connection with the accompany- 
ing drawings. 

BRIEF DESCRIPTION OF THE DRAWINGS 
[0016] 

Fig. 1 is block diagram showing the structure of 
each area of a drive according to an embodiment of 
the invention; 

Fig. 2 is a schematic diagram showing the structure 
of each area of a disc-shaped record medium 
according to the invention; 
Figs. 3A and 3B are schematic diagrams showing a 
wobbling groove of the disc-shaped record medium 
according to the invention; 
Fig. 4 is a schematic diagram for explaining the 
frame structure of the wobbling groove of the disc- 
shaped record medium according to the invention; 
Fig. 5 is a schematic diagram showing a sector for- 
mat of the disc-shaped record medium according to 
the invention; 

Fig. 6 is a schematic diagram showing a 32 kbyte 
format of the disc-shaped record medium according 
to the invention; 

Fig. 7 is a schematic diagram showing an inter- 
leaved state of an outer code in the 32 kbyte format 
of the disc-shaped record medium according to the 
invention; 

Fig. 8 is a schematic diagram showing the block 
structure of the disc-shaped record medium 
according to the invention; 

Fig. 9 is a schematic diagram for explaining a final- 
izing process; 

Fig. 1 0 is a schematic diagram for explaining record 
positions of WBBMs; 

Fig. 11 is a schematic diagram for explaining the 

data structure of a WBBM; 

Fig. 12 is a schematic diagram for explaining a 

redundant write operation of WBBMs; 

Fig. 13 is a schematic diagram for explaining a ring 

structure of WBBMs; 

Figs. 14A and 14B are schematic diagrams for 
explaining a WBBM having a bit map for user data; 
Fig. 15 is a flow chart for explaining a process per- 
formed when a medium is loaded to a drive; 



15 



35 



40 



45 



50 



3 



5 



EP0 908 882 A2 



6 



Fig. 16 is a flow chart for explaining a process per- 
formed when a write command is executed; 
Fig. 1 7 is a flow chart for explaining a process for 
updating a WBBM; 

Fig. 18 is a flow chart for explaining the finalizing 5 
process; 

Fig. 19 is a schematic diagram for explaining a read 
modified write operation. 

DETAILED DESCRIPTION OF THE PREFERRED 
EMBODIMENTS 

[0017] Next, with reference to the accompanying 
drawings, an embodiment of the present invention will 
be described. In the embodiment, a phase change type 
disc is used as a rewritable optical disc. In reality, two 
discs whose diameters are 120 mm and whose thick- 
nesses are 0.6 mm are adhered to form a rewritable 
optical disc. In addition, the rewritable optical disc has a 
wobbling groove. As will be described later, the wob- 
bling groove is wobbled with a signal of which an 
address (a position signal) is wobbled. A clock signal for 
signal processing and an absolute address on the disc 
can be extracted from the reproduced signal of the wob- 
bling groove. 

[001 8] In addition, the disc is rotated at CAV (Constant 
Angular Velocity). Data is recorded in a groove. In other 
words, a groove system is used. Data is recorded at 
CLD (Constant Linear Density) on the disc. The linear 
density is 0.35 i^m/bit. A predetermined range of linear 
densities is designated. A rewritable area of the disc is 
divided into many zones. In each zone, a linear density 
is defined. This type of disc is referred to as DVD+RW 
disc. However, it should be noted that the present inven- 
tion is not limited to a DVD+RW disc. In other words, the 
present invention can be applied to optical discs such 
as a groove/land record type disc and a magnetic opti- 
cal (MO) record disc. 

[001 9] Next, with reference to Fig. 1 , the structure of a 
disc drive for use with a rewritable optical disc such as a 
DVD+RW disc will be described in brief. In Fig. 1 , refer- 
ence numeral 1 is a phase change type optical disc. The 
optical disc 1 is rotated at CAV by a spindle motor 2. An 
optical pickup 3 is disposed so as to record data on the 
optical disc 1 and to reproduce data therefrom. 
[0020] Data of an external host processor 10 is sup- 
plied to the disc drive through an interface 4. A control- 
ler 5 is connected to the interface 4. A buffer memory 6 
is connected to the controller 5. The buffer memory 6 
stores write data or read data. Write data is supplied 
from the controller 5 to an encoder 7. The encoder 7 
converts the write data into sector-structured data, 
encodes each ECC block that is composed of 16 sec- 
tors with an error correction code, and adds a frame 
synchronous signal and a linking section. 
[0021] The frame-structured data is supplied to a 
recording system 8. The recording system 8 performs a 
digital modulating process and so forth. The recording 



system 8 supplies record data to a laser drive 9. The 
laser drive 9 generates a drive waveform corresponding 
to a predetermined level necessary for recording data to 
the optical disc 1 . Output data of the laser drive 9 is sup- 
plied to the optical pickup 3. 

[0022] The optical pickup 3 reproduces data on the 
optical disc 1 . The reproduced data is detected by a 
photo detector. The detected signal is supplied to an 
amplifying circuit 1 1. An output signal of the amplifying 
circuit 1 1 is supplied to a reproducing system 12 and a 
servo system 14. The amplifying circuit 11 calculates 
the detected signal of the photo detector and generates 
an RF signal, a tracking error signal, and a focus error 
signal. The RF signal is supplied to a reproducing sys- 
tem 12. The tracking error signal and the focus error sig- 
nal are supplied to a servo system 14. 
[0023] The reproducing system 12 performs a digital 
demodulating process. In addition, the reproducing sys- 
tem 12 processes a reproduced signal of a wobbling 
groove and demodulates an address. The separated 
frame synchronous signal and the address are supplied 
to the servo system 14. The servo system 14 performs 
a tracking servo operation and a focus servo operation 
for the optical pickup 3. In addition, the servo system 14 
performs a spindle servo operation and a sled servo 
operation for the optical pickup 3. In the sled servo oper- 
ation, the servo system 14 moves the optical pickup 3 in 
the radius direction of the disc. 
[0024] The reproduced data of the reproducing sys- 
tem 12 is supplied to a decoder 13. The decoder 13 
decodes an error correction code (namely, corrects an 
error of the reproduced data), disassembles the repro- 
duced data into sector-structured data, and performs 
another process. The reproduced data of the decoder 
13 is supplied to the controller 5. Thereafter, the repro- 
duced data is stored in the buffer memory 6. When a 
read command is received from the host processor 10, 
read data is sent to the host processor 10 through the 
interface 4. 

[0025] To drive the entire operation of the disc drive, a 
CPU 21 is disposed. A RAM 23 and a ROM 24 are con- 
nected to the CPU 21 through a bus 22. The ROM 24 
stores a program. A reproduced address of the repro- 
ducing system 12 is supplied to the bus 22. In addition, 
the controller 5 is connected to the bus 22. 
[0026] Next, an example of the rewritable optical disc 
1 will be described. Fig. 2 shows the structure of areas 
from the inner periphery side (lead-in side) to the outer 
periphery side (lead-out side) of the disc. In Fig. 2, the 
radius position and absolute address (in hexadecimal 
notation) of each area of the disc are denoted on the left 
side and the right side of the diagram. 
[0027] Emboss pits are recorded in the hatched areas 
on the innermost periphery side (from radius position 
22.6 mm to radius position 24.0 mm) and the outermost 
periphery side (after radius position 58.00 mm). In the 
emboss area (also referred to as ROM area), all "OOh" 
data, a reference code for 2 ECC blocks (from absolute 



15 



20 



25 



30 



35 



40 



45 



50 



4 



7 



EP 0 908 882 A2 



8 



address "2F00h"), and 186 blocks of control data (from 
absolute address "2F200h") are recorded. An ECC 
block is a data unit that composes an error correction 
block. An error correction code parity is added to data of 
every 32 kbytes (= 2 kbytes x 16). 
[0028] Control data and reference code are recorded 
when a master disc is cut. The control data and refer- 
ence code are read-only pit data. The control data 
includes physical management information and so forth 
of the optical disc. 

[0029] Areas other than the emboss area (namely, 
areas from radius position 24.0 mm to radius position 
58.0 mm) are rewritable areas of which tracks are 
formed with grooves (namely, groove area). In the 
groove area, a user area is from radius position 24.19 
mm to radius position 57.9 mm (from absolute address 
"31000h" to absolute address "1 AOEBFh"). 
[0030] In the rewritable areas on the inner periphery 
side and the outer periphery side of the user area, a 
guard zone, a disc test zone, a drive test zone, and a 
DMA (defect management area) are formed. The guard 
zone is formed so as to allow data written to the disc test 
zone and DMA to synchronize with a write clock. The 
disc test zone is formed so as to check the disc condi- 
tion. The drive test zone is formed so as to check the 
condition of the recording/reproducing drive. 
[0031] DMA1 and DMA2 are formed on the inner 
periphery side of the disc. DAM3 and DAM4 are formed 
on the outer periphery side of the disc. Same informa- 
tion is recorded in each of the DMA1 to DMA4. A 
detected result of a defect in the recordable area and 
information of a substitute sector are recorded in the 
DMA. Since the recording/reproducing operation is per- 
formed with reference to the contents of the DMA, a 
defective area can be skipped. The inner periphery 
areas of the rewritable area (other than the user area) 
and the emboss area on the innermost periphery side 
structure a lead-in area as a management area. 
[0032] In the groove area other than the emboss area 
on the optical disc 1 , tracks are pre-formed with wob- 
bling grooves. The wobbling grooves represent absolute 
addresses. Thus, the recording/reproducing apparatus 
can obtain information of absolute addresses and so 
forth with reproduced signals of grooves. 
[0033] Figs. 3A and 3B show examples of the struc- 
ture of grooves of the optical disc 1. As shown in Fig. 
3A, a pre-groove is spirally formed from the inner 
periphery to the outer periphery in a groove area of the 
optical disc 1 . 

[0034] As shown in Fig. 3B, the left and right side walls 
of the pre-groove 1a are wobbled corresponding to 
address information. In other words, the pre-groove 1a 
is wobbled at a predetermined period of a wobbling sig- 
nal generated corresponding to an address. A land 1b is 
formed between adjacent grooves 1 a. Data is recorded 
on a groove 1a. Thus, the track pitch is the distance 
between the centers of adjacent grooves 1a. The track 
pitch is for example 0.8 ^im. The groove width (the width 



of the bottom portion of each groove 1a) is for example 
0.48 urn. The width of each groove 1a is larger than the 
width of each land 1 b. 

[0035] The wobbling amount of each groove 1a is 
5 defined as the value of the wobble width WW. In this 
example, the wobble width WW is 12.5 nm. On each 
groove, the wobble amount instantaneously increases 
at predetermined intervals. A portion of which the wob- 
ble amount instantaneously increases is referred to as 
10 fine clock mark. In this portion, the wobble amplitude is 
for example 25 to 30 nm. 

[0036] One track (one turn of the disc) has a plurality 
of wobbling address frames. Each wobbling address 
frame is divided into eight portions in the direction of the 

is rotation of the disc. The eight portions are servo ele- 
ments (segment 0 to segment 7). Each servo segment 
(hereinafter simply referred to as segment) contains 48- 
bit information that is mainly an absolute address. The 
wobbling of each segment is composed of 360 waves. 

20 [0037] Fine clock marks are formed on a wobbling 
groove at equal intervals. With the fine clock marks, a 
PLL circuit generates a reference clock signal so as to 
record data. 96 fine clock marks are formed per rotation 
of the disc. Thus, 12 fine clock marks are formed per 

25 segment. 

[0038] Fig. 4 shows the structure of each wobbling 
address frame as segments (segment 0 to segment 7). 
In each (48-bit) wobbling address frame, the first four 
bits are used for a synchronous signal that represents 

30 the start of the wobbling address frame. The four-bit 
synchronous pattern is bi-phase data of which four-bit 
data is composed of eight channel bits. The next four 
bits are used for layer information that represents a 
layer number of a plurality of record layers or a layer 

35 structure of the disc. 

[0039] The next 20 bits are used for a track address 
(track number) as an absolute address. The next four 
bits are used for a segment number. The segment 
number is a value in the range from "0" to "7" corre- 

40 sponding to segment 0 to segment 7. In other words, 
the segment number represents the circumference 
position of the disc. The next two bits are reserved. As 
the last 14 bits of the wobbling address frame, an error 
detection code (CRC) is added. As was described 

45 above, fine clock marks are formed in each wobbling 
address frame at equal intervals. 
[0040] Data is read/written as each ECC block. One 
sector is composed of for example 2 kbytes. One block 
is composed of for example 32 kbytes. Fig. 5 shows the 

50 structure of one sector. One sector is composed of data 
ID (four bytes), I ED (two bytes), reserved area (six 
bytes), user data (2048 bytes = 2 kbytes), and EDC 
(four bytes). In other words, one sector is composed of 
a total of 2064 bytes. 

55 [0041 ] The data ID contains a track number and a sec- 
tor number corresponding to an address of the wobbling 
groove. The IED is an error detection parity correspond- 
ing to a data ID (for example, CRC). The EDC is an error 



5 



9 



EP0 908 882 A2 



10 



detection parity (for example, CRC) that is used so as to 
determine whether or not user data that has been error- 
corrected has an error. 

[0042] With 16 sectors (each of which has the struc- 
ture shown in Fig. 5), an ECC block shown in Fig. 6 is 
composed. Each sector is composed of 2064 bytes 
(172 bytes x 12). When 16 sectors (each of which is 
composed of 172 bytes x 12) is vertically arranged as 
shown in Fig. 6, a data array of (1 72 bytes x 1 92 (= 1 2 x 
16)) is formed. The user data of 192 x 172 bytes is 
encoded with a product code. In other words, data of 
each line (1 72 bytes) is encoded with an inner code (for 
example, Reed Solomon code). Thus, an inner code 
parity of 10 bytes (PI) is generated. In addition, data of 
each column (192 bytes) is encoded with an outer code 
(for example, Reed Solomon code). Thus, an outer 
code parity of 16 bytes (PO) is generated. 
[0043] Moreover, in block segmented data of 182 
bytes x 208 (= (172 + 10) x (192 + 16)), the outer code 
parity (PO) of 1 82 bytes x 1 6 is divided into data of 1 6 x 
(182 bytes x 1). As shown in Fig. 7, the divided portions 
of the outer code parity are interleaved with 16 sectors 
0 to 15 (each of which is composed of (1 82 bytes x 1 2)). 
In other words, each of the divided portions of the outer 
parity is placed at the end of each of the sectors . After 
the encoding process with the product code is per- 
formed, data of 13 (= 12 + 1) x 182 bytes is treated as 
data of one sector. 

[0044] When data of 182 bytes x 208 shown in Fig. 7 
is recorded on the disc, the data is recorded in the struc- 
ture of a transmission frame shown in Fig. 8. In other 
words, 182 bytes of each ligne is divided into two por- 
tions as 208 (rows) x 2 (frames). At the beginning of 
each portion of 208 x 2 frames, a linking section (data of 
link area) of 1 3 (rows) x 2 (frames) is added. More accu- 
rately, a part of data of linking sections for 26 frames is 
recorded at the end of the preceding block. The rest is 
recorded at the beginning of the current block. 
[0045] At the beginning of frame data of 91 bytes, a 
frame synchronous signal (FS) of two byes is added. 
Thus, as shown in Fig. 8, data of one frame is com- 
posed of a total of 93 bytes. Consequently, one block is 
composed of 221 (rows) x 93 x 2 bytes. In other words, 
one block (record/reproduction data unit) is composed 
of 442 frames. The size of the real data portion exclud- 
ing the overhead portion becomes 32 kbytes (= 2048 x 
16/1024 kbytes). 

[0046] As described above, according to the embodi- 
ment, one block is composed of 16 sectors. One sector 
is composed of 26 frames. A linking section is formed 
between two adjacent blocks. The linking section func- 
tions as an area for allowing data that is recorded or 
reproduced to synchronize with a clock signal. 
[0047] The present invention relates to a finalizing 
process necessary for allowing a ROM drive (for exam- 
ple, a DVD-ROM drive) to reproduce data from an opti- 
cal disc (for example, a DVD+RW disc). The data has 
been recorded on the optical disc by the above- 



described drive. Fig. 9 shows the concept of the finaliz- 
ing process according to the present invention. In Fig. 9, 
data is recorded as blocks in a user area of a rewritable 
area in which a wobbling groove is formed. 

5 [0048] When the DVD-ROM drive accesses the 
DVD+RW disc and reads data therefrom, the DVD-ROM 
drive repeats a coarse seek operation and a fine seek 
operation several times and obtains a target track. 
When the DVD-ROM drive performs the spindle servo 

10 operation and reads the data ID of each sector, if the 
data ID has not been recorded, the DVD-ROM drive 
cannot obtain a frame synchronous information as 
servo information. In this case, the spindle servo 
becomes out-of-control state. In addition, since the ID 

15 data is absent, the DVD-ROM drive cannot obtain posi- 
tion information. Thus, the DVD-ROM drive should 
always seek a recorded data area. Due to eccentricity 
or the like of the disc, even if the DVD-ROM drive jumps 
from the current track to a desired track, the obtained 

20 track deviates from the desired track to some extent. 
Thus, it is necessary to place dummy data (hereinafter 
referred to as finalization data) in such a range. 
Although the finalization data has no meaning (for 
example, all "0" data), the sector structure and the block 

25 structure thereof are the same as those of the above- 
described user data. Thus, the finalization data contains 
servo information (frame synchronous signal) and posi- 
tion information (ID). 

[0049] Fig. 9 shows an example of the state of which 
30 as the result of the finalizing process, finalization data is 
recorded before and after a recorded area of a user 
area, a rewritable area (test zone, DMA, and so forth) of 
a lead-in area, and a rewritable area (DMA) of a lead- 
out area. The data amount of finalization data that is 
35 recorded is equivalent to the width of several hundred 
tracks although it depends on the seek accuracy of the 
drive, the amount of eccentricity of the disc, and so 
forth. 

[0050] To perform the finalizing process, it is neces- 
40 sary to determine whether each block is a recorded 
block or non-recorded block. A bit map table that has 
bits that correspond to all blocks of the rewritable area 
and that represent whether the relevant blocks are 
recorded blocks or non-recorded blocks is created. In 
45 the bit map table, a recorded block and a non-recorded 
block are denoted by "1" and "0", respectively. When- 
ever a write command is executed, the bit correspond- 
ing to the relevant block is changed to "1". Thus, 
information that represents a recorded (written) block 
so can be used. This bit map is referred to as WBBM (Writ- 
ten Block Bit Map). 

[0051] In the structure shown in Fig. 1, the CPU 21 
receives information corresponding to a write command 
from the controller 5. Under the control of the CPU 21 , a 
55 WBBM is formed in the RAM 23. At a predetermined 
timing (that will be described later), the CPU 21 reads 
the WBBM from the RAM 23. The controller 5 records 
the WBBM to a predetermined area of the lead-in area 



6 



11 



EP 0 908 882 A2 



12 



of the optical disc 1 as with the user data. When the 
user issues to the host processor 10 (or the disc drive) 
a command for executing the finalizing process that 
causes, the command is sent to the CPU 21 . Thus, the 
CPU 21 causes the disc drive to write a predetermined 
amount of finalization data before and after each 
recorded block corresponding to the latest WBBM. 
[0052] As shown in Fig. 10, the WBBM is placed in the 
lead-in area along with a test zone, a DMA, and so forth. 
The WBBM can be placed in the range from 30000h to 
31000h of the lead-in area. Guard zones are preferably 
placed before and after the WBBM. Theoretically, the 
finalizing process can be performed with one WBBM. 
However, to improve the reliability of the finalizing proc- 
ess and decrease the number of times of the write oper- 
ation to the same area, it is very effective to provide a 
plurality of WBBMs (WBBM-1 to WBBM-N). Since the 
number of times of the write operation is limited in 
phase change type disc mediums (around 100,000 
times), if the write operation is repeatedly performed in 
the same area, the life of the medium is shortened. 
[0053] Next, an example of the structure of the WBBM 
will be described in detail. As described above, one 
block is composed of 16 sectors (32 kbytes). Since one 
DVD+RW disc has a storage capacity of around 3 
Gbytes, the disc has 90,000 to 100,000 blocks. When 
each block is correlated with one bit, a bit map of around 
12 kbytes is required. By adding management informa- 
tion to the bit map, one WBBM is structured. When a 
WBBM is recorded on the disc, as with user data, an 
encoding process with a product code and a frame 
structuring process are performed. In other words, one 
ECC block is composed of one WBBM. 
[0054] As shown in Fig. 1 1 , in one WBBM, a WBBM 
identifier, a ring number, an update counter, and zone 
information are added to bit map data. The bit map is 
composed of bytes. The upper right corner of the bit 
map represents a bit corresponding to a block of which 
the ECC block number is 1 . The ECC block number 
increases in the left direction of each byte. In addition, 
the ECC block number increases in the lower direction 
of the bit map. The left portion of Fig. 1 1 shows an 
enlarged view of the N-th byte. The N-th byte includes 
bits whose ECC block numbers are 8N to 8N+7. In the 
N-th byte, a bit whose value is "0" represents that an 
ECC block corresponding thereto is a non-recorded 
block. In contrast, a bit whose value is "1" represents 
that an ECC block corresponding thereto is a recorded 
block. 

[0055] The management information includes the fol- 
lowing items each of which is composed of one byte. 

WBBM identifier: A numeric value representing that 
a relevant ECC block is a WBBM (for example, 
OCOCh). 

Ring number: Represents the number of WBBMs 
that are treated as one set and the order of a partic- 
ular WBBM in the set. 



Update counter: A value that is incremented when- 
ever a WBBM is updated. A WBBM with the maxi- 
mum value of the update counter in the set of 
WBBMs is determined as the latest WBBM. A 

5 WBBM with the minimum value of the update coun- 

ter is updated to the latest WBBM. Thus, a write 
operation can be prevented from being concentrat- 
edly performed to a particular WBBM. Conse- 
quently, the disc medium can be prevented from 

w deteriorating. Even if data of the latest WBBM is 
destroyed, with information of a WBBM having the 
maximum value of the update counter, the 
destroyed WBBM can be almost restored. 
Zone information: When the finalizing process is 

is performed, it is not effective to check all bits. To 
solve such a problem, all the rewritable area is 
divided into a plurality of zones. When data has 
been written to all blocks of each zone, a flag that 
represents that data has been recorded to all 

20 blocks is set. Once the flag is set, the finalizing 
process is not performed for the zone. 

[0056] As shown in Fig. 12, to improve the reliability of 
the finalizing process, a plurality of WBBMs with the 

25 same content may be written. In this case, whenever a 
WBBM is updated, all the WBBMs are rewritten. 
[0057] Fig. 1 3 shows an example of the ring structure 
of a plurality of WBBMs (WBBM-1, WBBM-2, and 
WBBM-N). The update counter of each WBBM is initial- 

30 ized to for example "0". When the WBBM-1 is updated, 
the value of only the update counter thereof becomes 
"1". Next, when the WBBM-2 is updated, the value of 
only the update counter thereof becomes "2". Next, 
when the WBBM-3 is updated, the value of only the 

35 update counter thereof becomes "3". In such a manner, 
a WBBM with the minimum value of the update counter 
is updated. If the values of the update counters of two 
WBBMs are the same, a WBBM with a lower WBBM 
number is updated. Thus, a WBBM with the maximum 

40 value of the update counter is determined as the latest 
WBBM. 

[0058] Even if a WBBM is not the latest WBBM (even 
if several recorded bits are lost), the WBBM is effective 
information. In other words, before finalization data is 

45 written to an ECC block that is determined as an non- 
recorded block corresponding to the WBBM, the ECC 
block is checked. Even if the bit corresponding to the 
ECC block is incorrect, since the finalization data is writ- 
ten, recorded data is not destroyed. Thus, when a plu- 

50 rality of WBBMs are used and the oldest WBBM is 
rewritten, later WBBMs remain. In the case that a 
WBBM with the maximum value of the update counter is 
defined as the latest WBBM, when the drive spins up 
and reads a WBBM, it can determine the latest WBBM. 

55 [0059] The advantages of the ring structure of 
WBBMs are as follows. 

[0060] Since the number of times of the write opera- 
tion to a particular WBBM is decreased to 1 / (the 



7 



13 



EP0 908 882 A2 



14 



number of rings of WBBMs), the medium can be sup- 
pressed from deteriorating. 

[0061] Even if a defect such as power failure of the 
drive takes place during a write operation of a WBBM, 
since the preceding WBBM resides, it can be used as s 
the latest WBBM. 

[0062] A method for creating a plurality of WBBMs 
with the same content can be used (redundant write 
operation (see Fig. 12)). This method is the simplest 
countermeasures against a power failure. In this case, 
the values of all the update counters should be the 
same. If the counter value of a particular WBBM is dif- 
ferent from the counter values of the other WBBMs, it 
can be supposed that while a WBBM was being 
updated, a power failure took place. In this case, a 
WBBM with a larger value of the update counter is the 
latest WBBM. The ring structure and the redundant 
write operation can be used together. 
[0063] Next, with reference to Figs. 14A and 14B, 
other examples of a WBBM will be described. In the 
example shown in Fig. 1 4A, a user data map (referred to 
as user WBBM) is paired with the above-described 
WBBM (referred to as conventional WBBM). Since a 
conventional WBBM only represents whether each 
block is a recorded block or a non-recorded bloc, it can- 
not represent whether data of a recorded block is user 
data or f inalization data. In the user WBBM, a bit "1" is 
set to a block to which user data is written. Thus, a bit 
corresponding to a block to which finalization data is 
written is still "0". 

[0064] With the user WBBM, after a DVD-ROM drive 
has reproduced data from a DVD+RW disc to which 
finalization data had been written, a DVD+RW drive can 
write data to the DVD+RW disc. In this case, to allow the 
DVD-ROM drive to reproduce data from the DVD+RW 
disc, finalization data should be written to the DVD+RW 
disc. Since a conventional WBBM is composed of a bit 
map of user data and a bit map of finalization data 
(namely, the WBBM represents whether recorded 
blocks), the user data and the finalization data cannot 
be distinguished with the WBBM. As a result, finaliza- 
tion data is redundantly written. On the other hand, with 
both a user WBBM and a conventional WBBM, finaliza- 
tion can be prevented from being redundantly written. 
[0065] Unlike with the structure of which a user WBBM 
is paired with a conventional WBBM as shown in Fig. 
14A. a portion corresponding to each block on the bit 
map may be composed of two bits so as to distinguish a 
record block of user data and a record block of finaliza- 
tion data as shown in Fig. 14B. With such a bit map that 
allows user data and finalization data to be distin- 
guished, the finalizing process can be more effectively 
performed. 

[0066] When a DVD+RW disc is formatted, a WBBM 
is written to a predetermined area of the lead-in area of 
the DVD+RW disc. When a blank DVD+RW disc is for- 
matted, if the certificating process is not performed, all 
the user area becomes non-recorded state. On the 



other hand, if the certificating process is performed, all 
the user area becomes recorded state. When the 
DVD+RW disc is reformatted, since recorded data 
resides in the user area, the existing WBBM is used. 
[0067] When a DVD+RW disc is loaded to a drive, a 
WBBM is read to a memory (RAM 23 shown in Fig. 1) of 
the drive. Fig. 15 is a flow chart showing a process of 
the CPU 21 performed when a medium is loaded to the 
drive. At step S1 shown in Fig. 15, the medium is loaded 
to the drive. At step S2, the drive spins up and repro- 
duces a DMA and a WBBM in the lead-in area. The 
drive reads the first WBBM (at step S3) and checks the 
ring number (management information) of the WBBM 
(at step S4). When the WBBM is ring-structured, since 
there are a plurality of WBBMs, the drive reads all 
WBBMs in the RAM 23 and reads values of update 
counters thereof (at step S5). The drive compares the 
values of the update counters of all the WBBMs and 
leaves a WBBM with the maximum value of the update 
counter in the RAM 23 (at step S6). When the certificat- 
ing process has been completed or data has been writ- 
ten to all the user area, it is not necessary to leave the 
WBBM in the RAM 23 or update the WBBM. This deter- 
mination is performed by the CPU 21 of the drive. A flag 
is controlled corresponding to the determined result. 
[0068] Next, with reference to a flow chart shown in 
Fig. 16, a process of the CPU 21 for rewriting a WBBM 
stored in the RAM 23 will be described. This process is 
performed when a write command is executed. For sim- 
plicity, it is assumed that there is no user WBBM. When 
the drive spins up a medium (optical disc 1) and deter- 
mines that a conventional WBBM thereof should be 
managed, this process is performed. A write command 
from the host processor 10 is received (at step S11). 
When the execution of the write command is completed 
at step S1 2 (namely, it is determined that data has been 
recorded to all one block), the drive obtains a bit of the 
WBBM in the RAM 23 corresponding to the block on the 
bit map (at step S13), and determines whether or not 
the bit is "0" (at step S1 4). 

[0069] When the bit is "1 ", it represent that the block is 
a recorded block. Since it is not necessary to update the 
bit, the process is completed. In contrast, when the bit is 
"0", the bit corresponding to the block on the WBBM 
stored in the RAM 23 is set to "1" (at step S15). In addi- 
tion, a flag that represents that the WBBM stored in the 
RAM 23 has been updated is set (this flag is referred to 
as WBBM update request flag). In this case, the flag is 
set to "1 ". At a predetermined timing (in an eject state of 
the optical disc 1 , in a flash cache process, or in a back- 
ground state), the WBBM of the optical disc 1 is 
updated. After the WBBM has been updated, the 
WBBM update request flag is cleared. In the flag cache 
process, whenever a write command is received, data is 
temporarily stored in the write cache. Thus, a predeter- 
mined number of times of the write command can be 
executed at a time. The background state is a non-busy 
state of the CPU of the drive. 



15 



20 



25 



30 



35 



40 



45 



50 



8 



15 



EP 0 908 882 A2 



16 



[0070] Fig. 1 7 is a flow chart showing a process of the 
CPU 21 when WBBMs are updated. This process is 
executed at a predetermined timing. In this example, it 
is assumed that WBBMs are ring-structured. When the 
WBBM update request flag is "1", a WBBM is updated 5 
(at step S21). The update counter of the WBBM stored 
in the RAM 23 is incremented by "1" (at step S22). 
[0071] At step S23, a WBBM preceded by a WBBM 
that has been previously read is updated with the 
WBBM stored in the RAM 23. In this process, among 
some WBBMs of the optical disc 1 , a ring number corre- 
sponding to a WBBM with the minimum value of the 
update counter is set. A WBBM with the minimum value 
of the update counter is replaced with the latest WBBM 
stored in the RAM 23. Since the updating process is 
completed, the WBBM update request flag is cleared at 
step S24. 

[0072] To allow a DVD-ROM drive to reproduce data 
from a DVD+RW medium, the user issues a command 
that causes the drive to execute a finalizing process. 
Next, with reference to a flow chart shown in Fig. 18, the 
finalizing process of the CPU 21 performed by the drive 
will be described. At step S31 , when the drive receives 
the finalization command from the host processor 10, a 
WBBM on the optical disc 1 is replaced with a WBBM 
stored in the RAM 23. Thus, the WBBM stored in the 
RAM 23 is the latest WBBM. Alternatively, the latest 
WBBM may be read from the optical disc 1 . 
[0073] At step S32, with reference to the WBBM 
stored in the RAM 23, all non-recorded blocks adjacent 
to recorded blocks (bit = "1") in a predetermined range 
(for example, blocks equivalent to 300 tracks) are listed 
up. The listed blocks are denoted by B(0), B(1), B(2), ... 
and B(N-1). At step S32, the initial value of the variable 
I is (0). 

[0074] At step S33, it is determined whether or not the 
variable I is N. When (I = N), since the finalization data 
has been recorded to all non-recorded blocks, the 
updating process for the WBBM is preformed (at step 
S34) as described above (see Fig. 17). 
[0075] The finalization data is recorded from the block 
B(0) to the block B(N-1). In this case, it is determined 
whether or not an area to which finalization data is 
recorded corresponding to the WBBM is a non-recorded 
area. Even if it is determined that a particular block is a 
non-recorded block (bit = 0) corresponding to the 
WBBM, due to a power failure, the block may be a 
recorded block. When the block is a recorded block, if 
the finalization data is overwritten, recorded user data 
will be destroyed. To prevent such a problem, a read 
operation is performed for an area to which finalization 
data is recorded (at step S35). 

[0076] At step S36, it is determined whether or not 
data has been read. When data has been read or it is 
not necessary to record data, since the block B(l) is a 
recorded block or a record unnecessary block, the final- 
ization data is not recorded. When data cannot be read, 
the finalization data (dummy data) is recorded to the 



non-recorded block B(l) (at step S37). At step S38, the 
variable I is incremented. At step S39, the bit corre- 
sponding to the recorded block on the WBBM is set to 

"1". 

[0077] The reading operation for verifying an non- 
recorded block, the recording operation of the finaliza- 
tion data for a verified non-recorded block, the incre- 
menting operation for the variable I, and the process for 
setting the bit corresponding to the block on the WBBM 
to "1" are performed for all non-recorded blocks that 
have been listed up. Thereafter, at step S34, the bit cor- 
responding to a block that has been determined as a 
recorded block on the WBBM is set to "1". The WBBM 
stored in the RAM 23 is written to the optical disc 1 . 
[0078] In the flow chart shown in Fig. 1 8, a plurality of 
blocks that have been listed up are processed one after 
the other. Alternatively, all blocks that have been listed 
up may be read and determined whether or not they are 
recorded blocks. Thereafter, finalization data may be 
written to all non-recorded blocks. In this case, the proc- 
ess can be effectively performed and thereby preferably 
implemented. 

[0079] As described above, a WBBM is used to effec- 
tively perform the finalizing process. In addition, the 
WBBM can be used to effectively perform the read mod- 
ified write operation. A DVD-RW disc is accessed for 
data of 2 kbytes (one sector) at a time by the host proc- 
essor. Likewise, the buffer memory of the drive is 
accessed. On the other hand, the disc is accessed for 
data of 32 kbytes of a ECC block at a time by the drive. 
When the drive receives a read command for data of 2 
kbytes, it reads a block (32 kbytes) including the sector 
and sends the data of 2 kbytes to the host. In this case, 
the drive discards the remaining data of 30 kbytes. 
[0080] The write operation is more complicated than 
the read operation. As shown in Fig. 19, when the drive 
writes data of 2 kbytes to a particular block of the disc, if 
data has been recorded in the block, the drive should 
read the block, replace data of 2 kbytes of the relevant 
sector with write data received from the host processor, 
and then write data of 32 kbytes to the original block. 
This process is referred to as read modified write oper- 
ation. In this case, to write data of 2 kbytes to the disc, 
the drive reads data of 32 kbytes from the disc and then 
writes data of 32 kbytes thereto. To prevent the read 
modified write operation, the drive temporarily stores 
write data in a buffer memory (the buffer memory 6 
shown in Fig. 1) and completes the write command. 
This operation is referred to as write cache operation. 
[0081] Generally, the host computer tends to write 
successive sectors. Thus, as the host computer stores 
write data, data of one block may take place. In this 
case, the drive only performs the write operation for 
data of 32 kbytes without the read operation. The drive 
can write a plurality of blocks at a time. However, the 
drive may write data of 2 kbytes at a time. In addition, 
when the drive writes long data, it should perform the 
read modified write operation at the beginning and the 



15 



20 



25 



30 



35 



40 



45 



50 



9 



17 



EP0 908 882 A2 



18 



end of the data. 

[0082] When the drive performs the read modified 
write operation for a particular block, the block may be a 
non-recorded block. Generally, when the drive cannot 
read a block, it determines that the block is a non- 
recorded block corresponding to information such as a 
signal level. When the block is a non-recorded block, the 
drive places all "0" data in the block except for write data 
received from the host processor. In this case, when the 
drive can determine that the block is a non-recorded 
block, it can perform the write operation without the read 
operation. In other words, the performance can be 
improved two times. To improve the efficiency of the 
read modified write operation, a WBBM can be used. 
[0083] For a recorded block on a WBBM, when the 
drive writes a part of sector (2 kbytes), it should perform 
the read modified write operation. On the other hand, for 
a non-recorded block (bit = "0") on a WBBM, although a 
recorded portion may be treated as a non-recorded por- 
tion due to a power failure or the like, the block is almost 
a non-recorded block. Thus, the drive can place all "0" 
data in the block except for write data received and per- 
form the write operation without the read modified write 
operation. 

[0084] In most file systems, a medium is used in the 
ascending order of LBA (logical block address). Thus, 
the drive tends to write data in an area preceded by 
write data. On the other hand, in the case of a medium 
that is used without the certifying process, the probabil- 
ity of which an area preceded by write data is a non- 
recorded area is very high. 

[0085] Thus, in the case that the CPU 21 has read an 
area adjacent to a write area and determined that the 
read area is a non-recorded area, when the CPU 21 
receives a write command for the area, it can immedi- 
ately perform the write operation without the read modi- 
fied write operation. While the host processor 10 is not 
accessing the CPU 21, it checks a WBBM in the RAM 
23, reads a portion preceded by a recorded area of the 
optical disc 1, and determines that the portion is a non- 
recorded portion. This operation may be performed in a 
relatively narrow range for the next write command. 
[0086] When the CPU 21 receives a write command 
for the area (or caches the write command), if it has 
determined that the area is a non-recorded area, it 
places all "0" data as data in the same block other than 
the write data and performs the write operation, for 
example, without the read modified write operation. 
Alternatively, after the CPU 21 has performed the write 
operation, it updates the WBBM in the RAM 23. Thus, 
the drive determines whether or not the next area is a 
non-recorded area. 

[0087] The present invention is not limited to the 
above-described embodiment. Instead, various modifi- 
cations are available. For example, the present inven- 
tion can be applied to a rewritable disc-shaped record 
medium other than the DVD+RW medium and to a WO 
(Write Once) disc-shaped record medium. In addition, 



the present invention can be applied to a disc of which 
address information is recorded in other than wobbling 
groove format. Moreover, the servo information may be 
information for either CAV or CLV. Furthermore, f inaliza- 
5 tion data may be recorded before or after a recorded 
block. 

[0088] Having described specific preferred embodi- 
ments of the present invention with reference to the 
accompanying drawings, it is to be understood that the 

10 invention is not limited to those precise embodiments, 
and that various changes and modifications may be 
effected therein by one skilled in the art without depart- 
ing from the scope or the spirit of the invention as 
defined in the appended claims. 

15 [0089] According to the present invention, since a bit 
map that represents that each block is a recorded block 
or a non-recorded block is provided, in comparison with 
a method for analyzing a file system, the drive can exe- 
cute a finalizing process regardless of a file system for 

20 use. In addition, even if the number of directories/files is 
large, the drive can effectively perform the finalizing 
process. 

[0090] In addition, according to the present invention, 
in comparison with a method for reading all blocks and 

25 determining whether they are recorded blocks or non- 
recorded blocks, the drive can quickly perform the final- 
izing process. In addition, the user is not requested to 
perform the certifying process. Since the period neces- 
sary for the finalizing process is much shorter than the 

30 period necessary for the certifying process, the effi- 
ciency is very high for the user. 

[0091 ] When WBBMs are ring-structured, the number 
of times of the write operation for a WBBM to the same 
block can be decreased. Thus, the medium can be pre- 

35 vented from deteriorating. An area preceded by a 
recorded area is pre-read in background state. When a 
write command for the area is received, it is not neces- 
sary to perform the read modified write operation. Thus, 
the performance can be improved. In particular, in the 

40 case of the flush cache process, a write cache disable 
command, or a command with an FUAflag (that causes 
data not to be cached and write operation to be immedi- 
ately performed) is used, the operation is very effec- 
tively performed. 

45 

Claims 

1. A recording apparatus for use with a disc- shaped 
record medium having a user data area and a man- 
50 agement area, comprising: 

recording means (8) for recording at least one 
conventional bit map that represent whether or 
not each data unit for recording/reproducing 
55 has been recorded; 

and 

processing means for recording the bit map to 
the management area of the disc-shaped 



10 



19 



EP 0 908 882 A2 



20 



record medium (1), and referencing the bit map 
and adding a predetermined amount of data 
that contains at least one of servo information 
and position information to a non-recorded 
area in the vicinity of recorded data so as to 5 
allow a reproducing apparatus that reproduces 
data from a read-only disc-shaped medium (1) 
and obtains at least one of the servo informa- 
tion and the position information from a repro- 
duced signal to reproduce data from a w 
rewritable disc-shaped record medium (1). 

2. The recording apparatus as set forth in claim 1 
wherein the management area has a plurality of 
conventional bit maps and an update counter each 15 
of the bit maps has a value of an update counter 
that represents the number of update times of each 

of bit maps, and the processing means rewriting the 
plurality of bit maps successively and rewriting the 
value of the update counters of the bit map rewrit- 20 
ten corresponding to what represents the number 
of update times. 

3. The recording apparatus as set forth in claims 1 or 

2 wherein the management area has a plurality of 25 
the bit map, and the processing means rewrites 
redundantly the plurality of bit maps at a time. 

4. The recording apparatus as set forth in anyone of 
claims 1 to 3 wherein the management area having 30 
user data bit map which the conventional bit map is 
paired with, and the user data bit map represents 
whether or not the user data has been recorded for 
each record/reproduction data unit. 

35 

5. The recording apparatus as set forth in anyone of 
claims 1 to 4 wherein the conventional bit map com- 
prises a user data bit map, the user data bit map 
has a first bit and a second bit for each 
record/reproduction data unit, and one of the first bit 40 
and the second bit represents whether or not each 
record/reproduction data unit has been recorded 
and the other of the first bit and the second bit rep- 
resents whether or not the user data has been 
recorded for each record/reproduction data unit. 45 

6. The recording apparatus as set forth in anyone of 
claims 1 to 5 wherein the recording means (8) 
stores bit map data corresponding to the conven- 
tional bit map, the processing means performs an so 
updating process which rewrites the bit map data 
whenever a write operation is performed and which 
records the bit map data to the management area 

at a predetermined timing of which a write opera- 
tion and a read operation are not performed. 55 

7. The recording apparatus as set forth in claim 6 
wherein the predetermined timing is an eject state 



of the disc-shaped record medium 1 . 

8. The recording apparatus as set forth in claim 6 
wherein the predetermined timing is a flush cache 
state. 

9. The recording apparatus as set forth in claim 6 
wherein the predetermined timing is a background 
state in which a command is not received from the 
outside of the recording apparatus. 

10. The recording apparatus as set forth in anyone of 
the preceding claims wherein the processing 
means references the bit map, lists up a non- 
recorded area in the vicinity of recorded data, and 
records a predetermined amount of data that con- 
tains at least one of the servo information and the 
position information to the verified non-recorded 
area after verifying the non-recorded state of the 
non-recorded area by reproducing the listed non- 
recorded area. 

11. The recording apparatus as set forth in anyone of 
the preceding claims 1 wherein the processing 
means verifies whether or not a partial area pre- 
ceded by a recorded area is a non-recorded area 
before performing a write operation by referencing 
the bit map. 

12. The recording apparatus as set forth in claim 11 
wherein the processing means performs a write 
operation for the verified non-recorded area without 
performing a read operation of a read modified 
write operation. 

13. A recording method for use with a disc-shaped 
record medium 1 having a user data area and a 
management area, comprising the steps of: 

creating a bit map composed of bits that repre- 
sent whether or not each record/reproduction 
data unit has been recorded; 
recording (8) the bit map to the management 
area of the disc-shaped record medium; 
and 

referencing the bit map and adding a predeter- 
mined amount of data that contains at least one 
of servo information and position information to 
a non-recorded area in the vicinity of recorded 
data so as to allow a reproducing apparatus 
that reproduces data from a read-only disc- 
shaped medium (1) and obtains at least one of 
the servo information and the position informa- 
tion from a reproduced signal to reproduce 
data from a rewritable disc-shaped record 
medium (1). 

14. A disc-shaped record medium having a first rewrita- 



15 



35 



40 



45 



50 



11 



21 EP 0 908 882 A2 

ble area for recording user data and a second rewri- 
table area for recording management data, wherein 
at least one of servo information and position infor- 
mation is pre-recorded as wobbling information in a 
wobbling groove, and wherein the second rewrita- 5 
ble area has a bit map that represents whether or 
not each data unit for recording/reproducing for the 
first rewritable area has been recorded. 

15. The disc-shaped record medium as set forth in 10 
claim 1 4 wherein dummy data is added in the vicin- 
ity of recorded data in the first rewritable area and 
the second rewritable area. 

16. The disc-shaped record medium as set forth in 
claim 15 wherein the dummy data has servo infor- 
mation and position information which are neces- 
sary for a reproducing apparatus that reproduces 
data from a read-only disc-shaped medium (1). 



25 



30 



35 



40 



45 



50 



15 



20 



12 



EP 0 908 882 A2 



■5> 




CO 

' CM 



13 



EP 0 908 882 A2 



Fig. 2 



22.6mm 




REFERENCE CODE ^^^^^^ 




24.00mm 



W////////A 

CONTROL DATA 



24.19mm 



GUARD ZONE 



^ 30000h 



DISC TEST 
ZONE 



DRIVE TEST 
ZONE 



GUARD ZONE 



DMA 1&2 



REWRITABLE 
AREA 



2F0O0h 
2F020h 

2F200h 



31000h 



LEAD-IN AREA 



57.9mm 



58.0mm 



REWRITABLE 
AREA 



1A0EC0h 



DMA 3&4 



GUARD ZONE 



DRIVE TEST 
ZONE 



DISC TEST 
ZONE 



GUARD ZONE 




200000h 



□ 



EMBOSS (PRE-RECORDED) AREA 
GROOVE AREA 



14 



EP 0 908 882 A2 



Fig. 3A 




EP 0 908 882 A2 



Fig. 4 



48Bit 



SYNC 


LAYER 


TRACK NUMBER 




2 


CRC 


4 


4 


20 


4 




14 



SEGMENT NUMBER 



RESERVED 



Fig. 5 



j«* 2064 BYTES ^ 

| 4 | 2 | 6 |* 2048 *\ 4 | 



DATA 
ID 


IED 


RESERVED 


USER DATA 


EDO 



1 SECTOR *| 



16 



EP 0 908 882 A2 



Fig. 6 



1 2 BYTES 

Ai 



182 BYTES 



1 72 BYTES 



10 
BYTES 



208 
BYTES 



192 
BYTES 



16 i 
BYTES 



-Data- 



PO 



17 



EP 0 908 882 A2 



Fig. 7 




1 BYTE 



13 x 16 
= 208 
BYTES 



— 182 BYTES- 
172 BYTES 



10 
11 
12 
13 
14 



10 BYTES 
1 



1 SECTOR 
12+1 



L 
J 



PO 



18 



EP 0 908 882 A2 



LLI 

< 



00 

.Si 



o 
q: 



CO 
UJ 

> 



UJ 
< 
LL 



00 



CO 



CD , 



CO 
CO UJ 

if 

cc cr 

CO 
CM 



2 



CO 



< 
5c 

Q 



CO 



11 

O CO 

CM 



$1 

si 

CM CM 
CM 



19 



EP 0 908 882 A2 




20 



EP 0 908 882 A2 




EP 0 908 882 A2 



Fig. 11 



WBBM ID 
RING NUMBER 



UPDATE COUNTER 



ZONE INFORMATION 




8 BITS ► 



Fig. 12 



WBBM-1 



WBM-2 




SAME WBBM 



22 



EP 0 908 882 A2 



Fig. 13 





WBBM-1 



^ 




UPDATE COUNTER 







WBBM-N 



WBBM-2 



Fig. 14A 



Fig. 14B 









0 


0 


0 








0 


1 


0 








0 


1 


0 








0 


0 


0 








1 


1 


1 








1 


1 


1 








1 


1 


1 








1 


1 


1 





USER WBBM 



WBBM 




23 



EP 0 908 882 A2 



Fig. 15 



S1 



LOAD MEDIUM. 



S2< 



SPIN UP 



READ FIR 


ST WBBM. j 


1 


r 


CHECK RING NUMBER. 




r 


READ UPDATE 
COUNTERS OF ALL WBBMS. 




r 


LEAVE WE 
MAXIMUM 
UPDATE CO 
LATEST WBBJ^ 


JBM WITH 
VALUE OF 
UNTERS AS 
/I IN MEMORY. 



c 



END 



24 



EP 0 908 882 A2 



Fig. 16 



S11 — ^ WRITE COMMAND ^ 



S12 



EXECUTE WRITE 
COMMAND 



S13 



OBTAIN BIT 
CORRESPONDING TO 
WRITE BLOCK ON WBBM. 



S14 




S15 — - 


SET "1" TO BIT 
CORRESPONDING 
TO WBBM. 




i 


r 


S16 — - 


SET "1" TO WBBM 
UPDATE REQUEST 
FLAG. 




i 


r 



c 



END 



25 



EP 0 908 882 A2 



Fig. 17 



S21 



~<3 



UPDATE WBBM 



S22 



INCREMENT UPDATE 
COUNTER IN 
MEMORY BY "1". 



S23 



S24 



UPDATE WBB 
BY WBBM TH, 
PREVIOUSLN 
WBBM STORE 


M PRECEDED 
AT HAS BEEN 
f READ WITH 
D IN MEMORY. 




F 


CLEAR WBE 
REQUES 


3M UPDATE 
T FLAG. 



c 



END 



26 



EP 0 908 882 A2 



Fig. 18 




27 



EP 0 908 882 A2 



Fig. 19 



DISC MEDIUM 




-4 WRITE DATA 



ONE BLOCK IS WRITTEN 



32-KB BUFFER 



28