JP3770560B2 - CD player - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a CD (Compact Disk) reproducing apparatus, and more particularly to a CD reproducing apparatus capable of reproducing a disc in the middle of writing a recordable CD-R (CD Recordable).
[0002]
[Prior art]
Conventionally, a CD is known as a recording medium for recording acoustic information and the like. As shown in FIG. 3 (1), this CD records a lead-in (Lead IN) area in which index information of recorded information is recorded and actual music information from the inner periphery of the disc. An area and a lead-out area indicating the end of the program area are sequentially formed. The recorded signal is a digital signal modulated by a method called EFM (Eight to Fourteen Modulation) and includes a subcode such as a time code (time information) in addition to a main code (main information) such as music information. It is. Index information called TOC (Table Of Contents) is recorded in the lead-in area, and the total number of pieces of recorded information (for example, the total number of songs) recorded in the program area of the disc, the total recording time (for example, the total performance time) ) Etc. are recorded as subcodes. In the program area, music information or the like as a main code is recorded, and in the Q channel of the subcode, a track number (TNO) indicating a recording information piece number (for example, a song number), a recording time from the start of the track ( P-TIME: for example, the performance time of the song), total recording time measured from track number = 1 (A-TIME: for example, total performance time) and the like are recorded. In the lead-out area, a lead-out code indicating the lead-out area is recorded.
[0003]
In the CD playback device for playing back the CD, in normal playback, the recorded information in the program area is sequentially read from the inner periphery to the outer periphery for playback. Conventionally, the last track number of information recorded in the program area from TOC information in advance is managed by detecting and managing the end of the recorded information in the program area (hereinafter referred to as “disk end”) during such playback or fast forward (FF). (LTNO) is stored and managed,
one. When the lead-out area is detected,
two. When a track number greater than LTNO is detected,
Was determined to be a disk end.
[0004]
FIG. 4 shows a flowchart of a conventional disc end determination process during reproduction. That is, during reproduction, subcodes are sequentially read as information is read. First, the currently obtained subcode is compared with the previously obtained subcode (step S50). If they are equal, step S50 is repeated. If they are not equal, the current subcode is stored in the storage area of the previous subcode ( Step S51). Next, it is determined whether or not the lead-out area has been entered from the subcode information (step S52). If the lead-out area has been entered, it is determined that the disk is the end, and the innermost circumference of the program area, which is the next process, is determined. Go to the control process of moving the pickup 2 to the information (disk edge) of the first track number (FTNO) recorded in the field, and if it is not in the lead-out area, the current track number indicated in the subcode and the LTNO Comparison is performed (step S53). If the current track number is less than or equal to LTNO, the process goes to step S50 and repeats. If the current track number is larger, the disk end is determined, and the process proceeds to the same process as in step S52. As described above, the conventional CD playback apparatus determines the disk End.
[0005]
Incidentally, a CD having a recording format as described above is a reproduction-only recording medium. Recently, however, a CD-R has been developed that allows information to be added while adopting a format similar to that of a CD.
[0006]
This CD-R recording format standard is unified with a standard called “Orange Book”, and conforms to the CD format standard (commonly called Red Book). As shown in FIGS. 4 (2) (1) to (3), the CD-R disc is divided into three according to the recording state. That is, (1) a blank disc in which no information has been recorded yet, an unrecorded disc, (2) a disc in the middle of writing in which information is partially written (Partially Recorded Disc; hereinafter referred to as “PRD”), and (3) recording A finalized disc that is finally formatted to complete and have approximately the same format as a CD. As shown in the figure, in the CD-R, the lead-in area, program area, and lead-out area are finally formatted similarly to the CD.
[0007]
Further, a guide groove is formed in the recording track of the CD-R, and this guide groove is wobbling (meandering) at a frequency obtained by FM-modulating a carrier wave with data (ATIP: Absolute Time In Pregroove) indicating absolute time information. Yes. In a CD-R recording / reproducing apparatus, tracking and spindle control are performed by the guide groove, thereby recording and reproducing a blank disk and a PRD being written. Also, in the PRD, as shown in FIG. 4 (2) (2), a PMA (Program Memory Area) is provided as a temporary TOC area for storing a recording history of recording information on the inner periphery of the lead-in area I. Is provided. The following three types of information are recorded in this PMA. The first is the start address and end address of the recorded information recorded in the program area, and these are recorded in the same format as the TOC information recorded in the lead-in area of the CD. The second is disc identification information (optional), and numeric information of 6 digits (6 digits) for disc identification can be recorded as needed. The third is skip command information and skip cancel information, which is information that can be skipped for each track or a part of the track (time designation is possible) during disc playback. The reason why such information is recorded as a temporary TOC in the PMA is that there is a possibility that information will be additionally written in the remaining program area in the PRD, so until the final recording is instructed. This is because the TOC information cannot be recorded in the lead-in area.
[0008]
In the PRD, no information is written in the lead-in area I and the lead-out area O. Accordingly, each area remains in a mirror-finished state. In the CD-R recording apparatus, when finalization is instructed, predetermined information and TOC information recorded in the PMA are recorded as subcodes in the lead-in area I in order to finally make the same format as the CD. In the lead-out area O, predetermined information indicating the area is recorded as a subcode. As a result, the conventional CD playback apparatus can play back the finalized CD-R.
[0009]
[Problems to be solved by the invention]
As described above, a recordable CD-R has been developed and used. In the conventional CD playback apparatus, a finalized CD-R can be played back, but a PRD in the middle of writing is a program area. Although reproducible information is stored in the memory, the information has not been made reproducible. This is because, as described above, the PRD records the TOC on the PMA provided on the inner peripheral side of the lead-in area, but the conventional CD playback apparatus has a mechanism for accessing the PMA. It wasn't. Also, the lead-in area and lead-out area remain mirror-finished, and conventional CD playback devices have not been adapted to read control, such as the servo system running away in reading into the area.
[0010]
Therefore, in order to broaden the range of use of the CD-R, the applicant of the present invention can only read the TOC in response to a PRD in which the TOC cannot be read and the lead-in area and lead-out area are mirror-finished. We have developed a CD playback device that can play back the program area.
[0011]
However, when the PRD is played back by the conventional CD playback device, the last track number LTNO of the recorded information cannot be obtained in advance because the TOC information cannot be read. For this reason, the last track number LTNO of the searched information is obtained by searching for the last track number of the information actually recorded due to scratches or vibrations in the disc during the search. If the disc is recognized and set to be smaller, the conventional CD playback apparatus, as described above, determines that the disc is end by the stored track number even if there is recorded information thereafter. Therefore, the recording information after LTNO once stored and set cannot be reproduced. For example, if it is determined that 8 tracks are included due to protection or the like for a PRD in which 9 pieces of music are recorded, it is conventionally determined that the track end is detected when the track number of the 9th track is detected. The 9th song could not be played.
[0012]
The present invention has been made in view of such a problem, and in the case of CD-R recordable disc playback, when there is recorded information after the area corresponding to the track number indicating the last stored information, the last is recorded. It is an object of the present invention to provide a CD reproducing apparatus that can reproduce all of the recorded information by updating the track number.
[0013]
[Means for Solving the Problems]
In order to solve the above problems, a CD playback apparatus of the present invention includes a playback means for playing back and fast-forwarding information recorded in a program area of a disc that is being written to a recordable disc, and a last recorded in the program area. Storage means for storing a last track number indicating information, control means for controlling the playback means based on the stored last track number, and the program during playback or fast-forwarding of information recorded in the program area In the area after the area where the last information in the area is recorded, detection means for detecting a track number indicating the next information of the last information, and when the track number indicating the next information is detected, constituting the detected track number to the storage unit comprises an updating means for updating the final track number, the That.
[0014]
[Action]
In the CD playback apparatus of the present invention, when a normal CD is played, the track number indicating the last information recorded in the program area is stored and set according to the information recorded in the TOC, as in the prior art. In the reproduction of a recordable disk such as a disk in the middle of writing R, even if the track number indicating the last information is set once by the search, the disk end update means further subtracts the track number indicating the last information. When the track number indicating the presence of the information is detected, the detected track number is updated as the track number indicating the last information.
[0015]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 shows a basic configuration block diagram of a CD playback apparatus to which the present invention is applied.
[0016]
As shown in the figure, the CD reproducing apparatus includes a spindle motor 1 that rotates and drives a disk D, a pickup 2 that irradiates a pit on the disk D and photoelectrically converts the reflected light to reproduce an RF signal, A servo mechanism 3 that moves the pickup 2 in the radial direction of the disk D and positions it on the information track, an auto power controller (APC) 4 that keeps the output of the laser light in the pickup 2 constant, a spindle motor 1, a pickup 2, The servo unit 5 that servo-controls the servo mechanism 3, the preamplifier unit 6 that amplifies the RF signal reproduced from the pickup 2 and generates a servo control signal to the servo unit 5, and the RF signal amplified by the preamplifier unit 6 Audio data is demodulated by EFM and signal processing such as error correction is performed. A decoder unit 7 that also reproduces control data from the sub-coating, a D / A converter unit 8 that D / A converts audio data generated in the decoder unit 7 to generate an audio output, an operating state, etc. And a display / operation unit 9 for inputting an operation instruction, and a system controller unit 10 including a microprocessor, a memory, and the like, and controlling the entire apparatus.
[0017]
In the above configuration, when the disk D is a reproduction-only CD, the system controller unit 10 controls access to the lead-in area, inputs the TOC information via the decoder unit 7, stores the information, Similarly, a track number LTNO indicating the end of the information recorded in the program area is stored from the TOC information. On the other hand, since the TOC information cannot be obtained when the disk D is a PRD that is in the middle of writing information on the CD-R, the track number LTNO indicating the last information in the program area is obtained from the display / operation unit 9. When there is an input for instructing access, the last information in the program area is searched and the track number of that information is set to LTNO, and the subcode of that information is stored and set. The end of the program area is determined by the presence or absence of mirror finish. After the setting, during playback or fast-forwarding, when the sub-code of the information to be reproduced as a process of the disk end update means is monitored and compared with LTNO, and a sub-code indicating a track number larger than LTNO is detected. Update processing of LTNO is performed.
[0018]
FIG. 2 shows a flowchart of processing as the disk end update means during reproduction by the system controller unit 10.
The process as the disk end update means will be described with reference to the flowchart. First, it is determined whether or not the playback disk is a PRD (step S1). If it is PRD, the subcode of the information currently being read is obtained via the decoder unit 7 and compared with the LTNO in the storage subcode set as the last information, and the track number in the current subcode is set to LTNO. It is determined whether it is larger (step S2). If it is not larger, the process goes to step S4. If it is larger, the stored subcode is rewritten to the current subcode, and the last song number (LTNO) and the maximum of its absolute time are updated and stored ( Step S3). Then, the sub-code obtained now and the sub-code obtained before that are compared as in the conventional case (step S4). If they are equal, the process is repeated from step S1. Store (step S5). Next, it is determined whether or not the lead-out area has been entered (step S6). If the read-only disc is in the lead-out area, the disc end is determined and the next processing is performed. If not in the lead-out area, the current track number is compared with LTNO (step S7). If the current track number is smaller than or equal to LTNO, the process goes to step S1 and repeats. If it is larger, the disk end is determined and the process proceeds to the next process.
[0019]
As described above, in the CD playback apparatus of the present embodiment, the track number indicating the last information once set in the PRD playback is updated, so that when the last information is searched, it is determined as a mirror surface by scratches, vibrations, etc. If the track number is mistakenly set to be smaller than the track number of the last recorded information, the track number indicating the last information is detected when the subsequent information is detected during playback. Is updated, access is possible in subsequent searches. For example, in the playback of a PRD recorded with 9 songs, even if it is determined that 8 songs are recorded due to protection or the like, the track number of the last information is updated if the 9th song is detected during playback. The reproduction by the subsequent search becomes possible. Note that fast-forwarding is performed by track jumping, but even in that case, the subcode is read at any time and updated in the same way as during reproduction.
[0020]
【The invention's effect】
As described above, according to the CD playback apparatus of the present invention, when recording information exists after the last track number set once in the playback of a disc in the middle of writing information on the CD-R, the last track number is recorded. Since the search is possible after that, even if the track number indicating the last information is set to a small number by mistake, the recorded information can be reproduced.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a basic configuration of an embodiment of the present invention.
FIG. 2 is a process flowchart of a disk end update unit according to an embodiment of the present invention.
FIG. 3 is an explanatory diagram of a CD and a CD-R.
FIG. 4 is a flowchart of a conventional disk end determination process. .
[Explanation of symbols]
D ... Disk 1 ... Spindle motor 2 ... Pickup 3 ... Servo mechanism 4 ... Auto power controller (APC)
5 ... Servo unit 6 ... Preamplifier unit 7 ... Decoder unit 8 ... DA converter unit 9 ... Display / operation unit 10 ... System controller unit

Claims (1)

Reproduction means for reproducing and fast-forwarding information recorded in the program area of the disk in the middle of writing in the recordable disk,
Storage means for storing a last track number indicating the last information recorded in the program area;
Control means for controlling the playback means based on the stored last track number;
Detecting means for detecting a track number indicating information next to the last information in an area after the area where the last information is recorded in the program area during playback or fast-forwarding of the information recorded in the program area; ,
Updating means for updating the detected track number to the last track number with respect to the storage means when a track number indicating the next information is detected;
A CD playback apparatus comprising:

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