JPS59107406A - Disk record reproducer - Google Patents

Abstract

PURPOSE:To decrease the time required for reproduction of a lead-in area and to improve the operability by reading rationally the subsequent TOC (table of contents) data although a reproduction error arises to the first TOC data. CONSTITUTION:A start address corresponding to the undefined point data PD is written to an RAM26 although a reproduction error arises to the first TOC data. It is decided whether all start addresses are defined or not by checking whether the data PD is the last one obtained from the TOC data. If the data PD is the last one that is obtained from the TOC data, the processing is advanced to retrieve the start position of a program area at a high speed. Thus the TOC data is completely read. While the processing is reset if the PD data is not the last one obtained from the TOC data. Then the start address corresponding to the PD data is read out of the RAM26. In such a way, the time required for reproduction of a lead-in area with improvement of operability.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a CD (continuous disc) type disc record playback device, and in particular to a device for shortening the time required to play back data recorded on a lead intratrack. , related to improved operability.

[Technical background of the invention]

Recently, digital disc records (hereinafter referred to as discs) in which information signals such as audio signals are digitized (or ρCM) and recorded on discs, and disc record playback devices that play back the recorded information on these discs have been developed. ing.

In this type of disk, digitized information is recorded for the purpose of high-density recording of information, for example, as a series of pits continuously formed in a spiral shape on one surface. In addition, a disk record playback device reads out a bit string by having an optical pickup follow the pit string recorded on the disk using a tracking control system, and performs predetermined signal processing on this read signal. It is designed to play back signals such as the original audio signal. And, such a disc record playback device is
Since there is a huge amount of recorded information on a disc, in order to easily reproduce the desired recorded information, the pickup is moved at high speed in the forward and reverse directions of the disc's radial direction, and the recorded information is skipped. A high-speed forwarding function is provided for starting reproduction of desired recorded information. This high-speed feed 9 function is a fast-forward function that sends the pickup in the positive direction of the disk radius at high speed, a 9 (FF) II function,
This function is divided into a fast-reverse (REV) function that sends data in the opposite direction at high speed, and performs operations corresponding to, for example, the fast-forward and rewind operations of a tape recorder.

In other words, this high-speed transfer function enables the disk record playback device 6. It has become possible to perform so-called random access to search for a desired piece of divided digital data, and its operability has been improved.

For example, a CD (continuous disc) type disc, which is well known as a disc for such high-speed recording, is
A subcode signal called a PCM signal, which is a digitized audio signal, is recorded in the digital data (that is, recorded information). Digital data is a block made up of a predetermined number of frames. And 1
The digital data of the block includes one unit of subcode in addition to the PCM data.

Among these subcodes, a predetermined subcode Q is a code in which address data on the disc of digital data to be recorded and the like are recorded in a format as shown in FIG.

That is, one unit of the sashi code Q is formed by data reproduced in the order shown in the following items.

1. Synchronization/turn 0S1 indicating the start of the subcode 2. Control unit (CTL) for pre-emphasis and distinguishing between 2nd channel and 4th channel 3. Mode unit (ADH) indicating the data mode of subcode Q 4. Track ( A song number part IvINR5, which is data for subtracting the attributes of the digital data (music piece) recorded in the bit string (bit string) (music piece number), an index part X6, which is the index information of the song number, and a predetermined song number. Part MIN 7 showing the elapsed time (hereinafter referred to as relative time) from the start of playback of digital data of , Part 5EC8 showing the second part of the relative time, Divide 1 second of the relative time into a predetermined number of parts. The part FRAME 9 indicates the elapsed time in the case of 9, the part ZERO 10 contains the digital data, and the address indicates the minutes of elapsed time (hereinafter referred to as absolute time or address) since the disc started playing. Part MIN 11, Part ASEC12 showing the second portion of absolute time, Part AFRAME 13 showing the passage of time when one second of absolute time is divided into a predetermined number of parts, Part CR showing the error detection code of subcode Q. The subcode Q, which has a format such as
, MIN, and SEC are displayed on the display not only during playback but also when the pickup is moving at high speed, making it possible to search for any part of any desired song recorded on the disc in a short time. It is.

As can be seen from the above explanation, it was possible to perform arbitrary horizontal address system by fast forwarding and fast reversing operations referring to the address displayed on the display, but the song number and its index 1a information could be specified. By doing so, it is possible to construct a disc record reproducing apparatus which automatically performs fast forwarding or fast reversing operations, has a search function to search for a corresponding address, and provides extremely good operability.

Moreover, such a disc record reproducing apparatus has become easily available due to the development of microcomputer application technology, for example.

Incidentally, a disk track is configured such that the starting end is a lead-in area, the part where PCM data is recorded is a program area, and the ending part is a lead-out area. Of these, the program area records digital data including the subcode Q in the format shown in Figure 1, and the lead-in area records TOC (Table of Content) data, which will be described later. Digital data including a subcode Q is recorded.

Here, the format of the subcode Q recorded on the road-in track constituting the TOC data will be explained with reference to FIG. However, parts in FIG. 2 that are the same as those in FIG.

That is, the subcode Q recorded in the lead intratrack includes various data shown in the following items.

(1) POINT is the part that records point data indicating the attribute (track number) of the digital data recorded in the program area. (2) The address at which the digital data of the track number indicated by the point data starts (hereinafter referred to as the start address) (3) Part PMIN indicating the minute portion of the start address P5EC(
4) Part PFRAME that shows the passage of time when one second of the start address is divided into a predetermined number of parts.The subcode Q, which has this format, records the same data consecutively a predetermined number of times to compensate for playback errors. and constitute one subset data. The TOC data is composed of a plurality of subset data corresponding to the digital data of each song number recorded on the disc. This TOC
Data is recorded in the lead-in area multiple times in order to prevent playback errors as much as possible.

In other words, by reading and storing such TOC data when the pickup is lead-in to a track in the lead-in area, the start address of the digital data for each song number can be known in advance, and the search function can be activated extremely quickly. This allows operations (hereinafter referred to as search operations) to be performed. However, it is essential to read TOC data completely without errors in order to perform a search operation quickly.

[Problems with background technology]

However, due to dust, dirt, moths, etc. on the disc, playback errors occur frequently and the first TOC data in the lead-in area may not be completely read. In such a case, the conventional disc record playback apparatus starts playing the next TOC data and waits until the subset data in which the playback error occurred is obtained. Therefore, if playback errors occur on a disc with a large number of digital data tracks, or if there are many playback errors and a large number of unreadable subset data,
There is a problem in that it takes a very long time to completely read the TOC data.

[Purpose of the invention]

This invention was made in view of the above points, and the first T
Even if a playback error occurs when playing back the OC data, the time required to play the lead-in area can be shortened as much as possible by reading subsequent TOC data rationally, thereby making it extremely An object of the present invention is to provide a disc record playback device with good operability.

[Summary of the invention]

In this invention, a plurality of PCM digital data are recorded in a program area along with track numbers and addresses,
In a disc record playback device that plays back a disc in which point data indicating the song number of each digital data and table-op content data having a predetermined start address corresponding to the point data are recorded in the lead-in area, the first table-op content data is recorded. a first means for reading content data and storing a start address corresponding to each point data; and a start address that could not be detected by the first means. The present invention is characterized by comprising second means for searching at high speed by a fast-forwarding operation from among the table of contents data recorded from the second time onwards, and selectively reading and storing the data.

[Embodiments of the invention]

An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 3 shows the configuration of a disc record reproducing apparatus according to the present invention, in which a control circuit 11 comprising a microcomputer and an interface circuit is connected to an RO.
M12 is used to execute a predetermined program, and there are playback controls, stop controls, and fast forward (FF) controls.
Operator, quick return REV) Operator, switch that serves as search operator (Sp), (S8) t (SF) t
(SR) and (S8R) are connected. The control circuit 1 includes each switch (sP),
(s8) , (sF) , (SR) , (s8R
), the disc playback system 13 is controlled to a predetermined state in response to the operation of the subcode Q, and address data such as the track number, index, relative time, etc. obtained by the subcode Q is displayed on the display 14. There is.

That is, in the disc reproducing system 13, when the disc motor 16 and the pickup motor 17 are driven from the control circuit 11 via the external control circuit 15, the data recorded on the disc 18 is reproduced by the pickup 19. Then, the reproduced signal is sent to the RF signal detection circuit 20. This RF signal detection circuit 20 separates the reproduced signal into a signal supplied to a servo circuit 21 and a signal supplied to a demodulation circuit 22.

Here, the Boo 2 circuit 21 is a focus sensor for the picker f19. and tracking serve, and also sends out various signals to the pickup feed shimoter 17 for near tracking serve.

Further, the demodulation circuit 22 separates a subcode Q for address data detection from the reproduced signal, supplies the subcode Q signal to the address detector 23, and demodulates the reproduced signal from which the subcodes have been separated (gFM). The signal is then supplied to the D/A converter 24.

The reproduced data converted back to an analog signal by the D/A converter 24 is subjected to necessary processing such as error correction, deinterleaving, error correction, etc., and is then provided to the speaker 25 to produce sound. It turns out.

The subcode Q signal (address signal) detected by the address detector 23 is provided to the control circuit 11 to perform necessary control functions.

On the other hand, the control circuit 11 includes a point data output section (O
PD) and address input/output section (IOAD) are respectively connected correspondingly to the address input section (IA) and data input/output section (IOD) of the RAM 26, and point data (lead-in area (indicated by POINT of subcode Q) of P
MIN, PSEC.

The start address indicated by PFRAME can be written and read freely. In addition, the above RAM
26 control input terminals (Io, ) and (IRw), a chip selection signal and a read/write control signal are input to the output terminals (Oo, ) and (ORw) of the control circuit 11, respectively.
It is now supplied from

The control circuit 11 also controls the control input terminals (IFD) and (ONT) of the external control circuit 15 to control the FD for forcibly moving the big disk f19 in the positive radial direction of the disk 18 at high speed. A signal and a CNT signal that searches for the start position of the program area at high speed and stops the movement of the pickup 19 to enter a pause state are supplied from the output terminals (07D) and (0ONT) via switching circuits 27 and 28, respectively. It looks like this. Each of the above switching circuits 27 and 28
A control signal for controlling on/off is commonly supplied to each control input terminal from the output terminal (Os, r) of the control circuit 11.

Next, the characteristic operation of the disc record reproducing apparatus constructed as described above will be explained with reference to the flowchart of FIG.

That is, when it is detected that the disk 18 is completely attached to the rotating shaft of the disk 16, the control circuit 11 controls the disk motor 16. The pickup feed motor 17 and the like are driven to start reproducing the lead-in area of the disc 18. After this, the control circuit 1 is operated as shown in the flowchart of FIG.
The process shown in (S12) is executed as described below.

(1) In Stella f (S,), fixed data (ADf) with a predetermined bit pattern indicating that the start address corresponding to the point data of TOC data is undefined
is written into a predetermined storage area of the RAM 26 where each start address is to be stored, and the processing is transferred to Stella f (S2).

(2) In step (S2), the address detection circuit 2
Point data PD from subcode Q supplied from 3
and the start address AD, and input the start address AD 'f:i corresponding to the predetermined location of the RAM 26 specified by this point data PD, and store the point data as the first point data (PD, ). , the process moves to step (S6).

(3) In step (S5), the next point data PD and start address AD are separated from the subcode Q, the start address AD corresponding to the predetermined location of the RAM 26 specified by this point data PD is written, and the process is started. Move to step (S4).

(4) In step (S4), the point data PD obtained in step (S,) and the point data PD stored in step (S2) are compared to see if they are equal, and if they are not equal, the process is carried out in step (S3). ), and if they are equal, each switching circuit 27, 28 is turned on, and the process proceeds to step (85').

As a result, the start address AD corresponding to all the point data PD of the TOC data recorded on the disk 18
is stored in the RAM 26. however,
In steps (S2) and (S3) subcode Q
If a playback error occurs, the relevant point data P
At the start address corresponding to D, the successive write control signal is not outputted and 1: is not written into the RAM 26.

(5) In step (S5), for example, the content of the address corresponding to the first point data PD (that is, the start address AD) is read out from the RAM 26, and the process is carried out in step (S6).
).

(6) Stella f (S6), by checking whether the start address AD obtained in step (S5) is fixed data AD, the start address AD corresponding to the predetermined point data "' PD is undefined. If it is undefined, the process advances to step (S7), and if it is defined, the process advances to step (S,
, ).

(7) In Step 3 (S7), the point data whose start address is undefined is stored as PD2, and the process proceeds to Stella f (S8).

(8) In step (S8), the PD of step (S7)
2 and the point data of the played sag code Q. If they do not match, proceed to Stella f (S,), and if they match, proceed to Stella f.
It is now possible to proceed to (S1o).

(9) In step (S, ), a fast forward operation is performed in which the FD signal is output from the output terminal (OFD) via the switching circuit 27 for a predetermined period of time to move the picker f19 at high speed in the positive radial direction of the disk 18. Thereafter, the process returns to step (S8) as a normal playback state.

In step α1 (S18), after writing the start address obtained from subcode Q to the address of RAM 26 corresponding to PD2, the start address PD corresponding to the next point data PD stored in RAM 26 is read. Then, the process returns to Stella f (S5).

Through the series of processes shown in steps (S5) to (S, .), even if a reproduction error occurs in the initial TOC data, the undefined point data PD is stored in the RAM 26. The starting address corresponding to is written.

In the step αη step (Sl,), for example, the step (s8
) is the last point data obtained from the TOC data to determine whether all starting addresses have been defined for each point data. If it is the last point data, the process proceeds to step (812), and if it is not the last point data, the process returns to step (S8) and the start address corresponding to the next point data is read from the RAM 26.

(To) In step (S12), the CNT signal is output to search the start position of the program area of the disk 18 at high speed, and the picker f19 is stopped and the pause state is established.
The OC data reading operation is completed.

In other words, a disc record playback device that performs the series of processes described above reads the initial TOC data once and then reads the corresponding start address only for the point data where the playback error occurred. Even if a playback error occurs, all four start addresses corresponding to each point data can be read in a very short time, and the next playback operation, fast forward operation, and search operation can be performed quickly. It can be said that it has extremely good operability.

Although omitted in the above explanation, the disc record playback device according to the present invention is designed such that the track number and index required for the search operation are specified using a numerical designation operator not shown in Figure 3. There is. Further, this disc record playback device may be provided with a dedicated operator for performing a pause operation.

Furthermore, it goes without saying that the present invention is not limited to the above embodiments, and that various modifications and applications are possible without departing from the gist of the present invention.

〔Effect of the invention〕

As detailed above, according to the present invention, even if a reproduction error occurs when reproducing the first TOC data, subsequent TOC data
By reading the C data rationally, it is possible to shorten the time required for reproducing the lead-in area as much as possible, thereby providing a disc record reproducing apparatus with extremely good operability.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the format of the subcode Q in the program area of the disc, Figure 2 is a block diagram showing the subcode in the lead-in area of the disc, and Figure 4 explains the main operations of the device in Figure 3. This is a flowchart used for this purpose. 1. Control circuit, 12. ROM, 7. ,?・・・
Disc playback system, 14...Display unit, 15...External control circuit, 16...Disc motor, 17...Pickup feed motor, 18...Disc, 19...Pickup, 20... RF detection circuit, 21... Servo circuit, 22... Demodulation circuit, 23... Address detection circuit, 24... D/A conversion circuit, 25... Speaker, 26... RAJj/1, 27.28...Switching circuit.

Claims (1)

[Claims] A plurality of digital data converted into PCM are recorded in the program area with track numbers and addresses, and a table option having point data indicating the track of each digital data and a predetermined start address corresponding to the point data is recorded in the lead-in area. In a disc record playback device that plays back a disc on which content data is recorded, a first table of content data is read out and a start address corresponding to each point data is stored.
and a second means for searching at high speed by a fast-forward operation from among the table of contents data recorded after the second time for the start address that could not be detected by the first means, and selectively reading and storing the data. 1. A disc record playback device comprising: means.