JPH0877689A - Information recorder/reproducer - Google Patents

Abstract

PURPOSE: To shorten the time required for determining the modulation system of a recording medium at the time of starting a recorder/reproducer by recognizing the pattern of a data recorded on a disc thereby determining the modulation system of the recording medium. CONSTITUTION: When a spindle motor 2 reaches a predetermined rotational speed, a pattern recognition circuit 11 reads in a signal from an optical head 4 and recognized the pattern of a data previously recorded on a disc 1 while corresponding to code A and code B thus determining the modulation system of the disc 1. A decision is then made whether the modulation system is determined normally and when it is determined normally that the disc 3 corresponds to code A or code B, a selector in the circuit 11 selects one of two modulation/ demodulation circuit 9 corresponding to a modulation system thus determined.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording / reproducing apparatus for recording / reproducing information on / from a recording medium, and more particularly to an information recording / reproducing apparatus for recording / reproducing information by a plurality of modulation / demodulation methods.

[0002]

2. Description of the Related Art Conventionally, in an information recording / reproducing apparatus such as an optical disk device or a magneto-optical disk device, there are a plurality of standards for the medium including the size of the recording medium. Generally, it is a dedicated information recording / reproducing device. For example, a plurality of modulation / demodulation methods are known for recording / reproducing information, and the modulation / demodulation method of information may differ depending on the recording medium. Therefore,
In such a case, one device cannot support a plurality of modulation / demodulation systems, and therefore, it is general to perform recording / reproduction with a device dedicated to each modulation / demodulation system of each medium.

Therefore, recently, there have been available devices capable of reproducing or recording information recorded on recording media in respective standards. FIG. 7 is a block diagram showing an example of such an information recording / reproducing apparatus. In the figure, reference numeral 1 denotes an optical disk (or magneto-optical disk) which is an information recording medium, and is rotated at a predetermined speed by driving a spindle motor 2. The optical disk (magneto-optical disk) 1 will be simply referred to as a disk hereinafter. An optical head 4 is provided on the lower surface of the disk 1, and information is recorded and reproduced by irradiating the optical beam 4 from the optical head 4. Inside the optical head 4, a semiconductor laser as a light source, an objective lens for narrowing the laser beam into a minute light spot, an optical sensor for detecting the reflected light from the disc 1, and an objective lens driven to drive the optical beam 3 on the disc 1. An actuator or the like for adjusting the position of is provided. The optical head 4 can be moved in the radial direction of the disk 1 by driving the linear motor 5 to access a desired track on the disk 1.

Reference numeral 9 denotes a modulation / demodulation circuit that modulates recording data by a predetermined modulation method when recording information, and demodulates when reproducing to generate reproduction data. The modulation / demodulation circuit 9 corresponds to two modulation / demodulation methods, and an A code modulation / demodulation circuit and a B code modulation / demodulation circuit.
It is composed of two modulation / demodulation circuits of a code modulation / demodulation circuit. A
The modulation / demodulation circuit for the code and the B code is, for example, a modulation / demodulation circuit for 1-7 modulation, 2-7 modulation, or the like. Reference numeral 10 denotes a CPU for controlling each unit of the apparatus to control the information recording / reproducing operation of the apparatus. That is, the CPU 10 controls the actuator drive circuit 6, the linear motor drive circuit 7, and the spindle motor drive circuit 8, and the optical head 4
Is performed, and the rotation speed of the spindle motor 2 is controlled. In the CPU 10, the modulation / demodulation circuit 9
Control such as switching between two modulation / demodulation circuits is also performed.

Next, the operation of the apparatus shown in FIG. 7 at startup will be described with reference to FIG. In FIG. 8, first, when the device is powered on (S1) and the disk 1 is set in the device body (S2), the CPU 10 sets a predetermined A code modulation / demodulation (S3). Next, the spindle motor drive circuit 8 is controlled to drive the spindle motor 2, and the rotation speed is controlled so that its rotation speed is synchronized with the A code modulation / demodulation method (S4), and the rotation speed of this spindle motor 2 is set. While reaching speed,
The A code modulation / demodulation circuit of the modulation / demodulation circuit 9 is activated (S
5). When the A code modulation / demodulation circuit is activated, the CPU 10 controls the linear motor drive circuit 7 to cause the optical head 4 to seek the control track of the disk 1, and the information recorded on the control track is read (S6). Then, the CPU 10 determines whether or not the information on the control track is normally read (S7).

Information necessary for controlling the disc 1 is recorded on the control track. If the information can be read normally, it can be demodulated by the A code modulation / demodulation circuit. It can be determined that the disc is compatible with the A code modulation / demodulation method. Therefore, at this time, the modulation / demodulation circuit is determined to be the A code modulation / demodulation circuit, and the write test is performed on the predetermined area of the disk 1 (S8). That is, a write test is performed to confirm the operation of the device, and if the test result is acceptable, the startup process ends. Therefore, after that, recording and reproducing of information is performed by the A code modulation / demodulation method.

On the other hand, if the information on the control track could not be read out normally, the disc 1 is A
Since it is not the code modulation / demodulation system, the CPU 10 changes the rotation speed of the spindle motor 2 (S9), and the B code modulation / demodulation circuit having the second highest priority is activated (S1).
0). Then, the information of the control track is read again (S11), and it is determined whether the information can be read normally (S12). If the disc can be read normally, the disc corresponds to the B code modulation / demodulation method, so that the B code modulation / demodulation circuit is determined, the write test is performed again, and the start-up process is completed. If the data cannot be read normally, abnormal state processing is performed (S13). That is, the disk is A
Since neither the code nor the B-code modulation / demodulation method is used, processing such as notifying the host computer that information cannot be recorded or reproduced is performed.

[0008]

In the conventional information recording / reproducing apparatus described above, when a disc for modulation / demodulation of A code and B code is used, a startup process as shown in FIG. The modulation / demodulation system can be switched, and information can be recorded / reproduced on / from a disc of a different modulation / demodulation system by one device. Therefore, in such a case, it is unavoidable that it takes a considerable amount of time to confirm the modulation / demodulation method of the disc. However usually 1
In one apparatus, a disc of a specific modulation / demodulation method is often used, such as a disc of A code only or a disc of B code only. Therefore, in such a case, even in an apparatus using only the B code disc,
As described with reference to FIG. 8, it is necessary to confirm whether the disc is an A-coded disc and then the B-coded disc. Therefore, the information of the control track is read twice. Double the processing time was required to confirm the modulation / demodulation method.

The present invention has been made in view of the above circumstances, and an object thereof is to allow a process for confirming a modulation / demodulation system of a recording medium to be performed only once, thereby reducing the time required to confirm the modulation / demodulation system. An object of the present invention is to provide an information recording / reproducing device that can be significantly shortened.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to provide an information recording / reproducing apparatus having a plurality of modulation / demodulation circuits for recording / reproducing information on / from an information recording medium by different modulation / demodulation systems from each other. Providing means for discriminating the modulation / demodulation method of the recording medium by pattern recognition of data, and selecting a modulation / demodulation circuit corresponding to the recording medium from the plurality of modulation / demodulation circuits based on the discrimination result of the discrimination means. Is achieved by an information recording / reproducing apparatus.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of an information recording / reproducing apparatus of the present invention. In FIG. 1, the same parts as those of the conventional device of FIG. 7 are designated by the same reference numerals. In FIG. 1, 1 is a disk which is an information recording medium, 2 is a spindle motor, 4 is an optical head, and 5 is a linear motor. All of these are the same as those shown in FIG. 7. It should be noted that predetermined data, such as a control track or a home position, of the disc 1 is recorded with predetermined data corresponding to a modulation / demodulation method of A code and B code. 6 is an actuator drive circuit, 7 is a linear motor drive circuit, 8 is a spindle motor drive circuit, and 9 is a modulation / demodulation circuit. These circuits are also the same as those in FIG. 7, and the modulation / demodulation circuit 9 is provided with two modulation / demodulation circuits corresponding to the A code modulation / demodulation system and the B code modulation / demodulation system as in FIG.

Reference numeral 11 denotes a pattern recognition circuit for determining the modulation / demodulation method of the disk 1 by recognizing the pattern of the data recorded at a predetermined position on the disk 1 as will be described later in detail. A selector (not shown) is provided in the pattern recognition circuit 11, and two modulation / demodulation circuits of the modulation / demodulation circuit 9 are switched so as to correspond to the modulation / demodulation system of the disk 1 based on the determination result of the pattern recognition circuit 11. . Further, when the modulation / demodulation circuit is switched in this way, in the CPU 10, the spindle motor drive circuit 8
The rotation speed of the spindle motor 2 is controlled in accordance with the A code modulation / demodulation and the B code modulation / demodulation, respectively.

FIG. 2 is a circuit diagram showing a specific example of the pattern recognition circuit 11. In the present embodiment, in the case of the A code modulation / demodulation type disc, "1011" is set at a predetermined position as an example.
A pattern in which data of "0" is repeated three times is recorded, and B
It is assumed that the code modulation / demodulation type disc has recorded therein a pattern in which data "11100" is repeated three times. The pattern recognition circuit 11 is provided with the same number of comparison circuits 12 as the number of bits of the data recorded in advance on the disk 1 as described above, and the data read from the disk 1 is synchronized by the synchronization circuit as shown in FIG. (Not shown) is loaded into each comparison circuit 12 in synchronization with the system clock. Although FIG. 2 shows only five comparison circuits 12,
Actually, 15 comparison circuits 12 are provided. Also,
As shown in FIG. 2, each comparison circuit 12 compares the comparison data (“10110” with 3 data corresponding to the A code modulation / demodulation type disc).
Repeated data) and comparison data corresponding to a B code modulation / demodulation type disc (data obtained by repeating “11100” three times) are input, and in each comparison circuit 12, each comparison data corresponding to A code and B code is input. And the data read from the disk 1 are compared with each other.

Here, when the data read from the disk 1 is the data of 10110 ... And the data corresponding to the A code, when the comparison data is the data corresponding to the A code modulation / demodulation system, The comparison results of the comparison circuit 12 are all in agreement. Therefore, in this case, the determination circuit 13
Then, a signal for detecting the target pattern corresponding to the A code is output. On the other hand, when the data read from the disk 1 is 11100 ... And the data corresponding to the B code, the comparison signal from each comparison circuit 12 when the comparison data is the data corresponding to the B code modulation / demodulation method. Is output. Therefore, at this time, the determination circuit 13 outputs a signal for detecting the target pattern corresponding to the B code. In this way, the pattern recognition circuit 11 performs pattern recognition on the data recorded on the disk 1 to
Is determined according to the A code modulation / demodulation method or the B code modulation / demodulation method.

Next, the operation of the embodiment shown in FIG. 1 when the apparatus is started up will be described with reference to FIG. In FIG. 4, when the power of the apparatus is first turned on (S1) and the disk 1 is set in the apparatus main body (S2), the CPU 10 controls the spindle motor drive circuit 8 to drive the spindle motor 2 to drive the spindle motor 2 The rotation speed of is controlled to a predetermined speed (S3). At the same time, the linear motor drive circuit 7 is controlled to drive the linear motor 5, and the optical head 3 is recorded in the recording area of the data previously recorded on the disk 1 in accordance with the modulation / demodulation method of the A code and the B code as described above. Seek.
Next, the CPU 10 activates the pattern recognition circuit 11 until the rotation speed of the spindle motor 2 reaches a predetermined speed, and waits for a signal from the optical head 3. Of course, although not shown in FIG. 4, the focus servo and the tracking servo are sequentially activated.

When the rotation speed of the spindle motor 2 reaches a predetermined speed, the pattern recognition circuit 11 reads the signal from the optical head 4 (S4), and as shown in FIGS. , The pattern recorded data corresponding to the B code is used to determine the modulation / demodulation method of the disc 1 (S5). When the determination is completed, it is determined whether or not the modulation / demodulation method of the disk 1 can be normally determined (S6), and when the disk 1 can be normally determined to be either the A code or the B code, The selector in the pattern recognition circuit 11 selects the modulation / demodulation circuit corresponding to the modulation / demodulation method determined from the two modulation / demodulation circuits of the modulation / demodulation circuit 9 (S7). That is, if the disk 1 is of A code, the A code modulation / demodulation circuit is selected, and if it is of B code, the B code modulation / demodulation circuit is selected.

When the modulation / demodulation circuit is selected, information on the control track is read to confirm whether data can be demodulated normally. That is, the CPU 10 activates the selected modulation / demodulation circuit (S8) and controls the linear motor drive circuit 7 to cause the optical head 4 to seek the control track. Then, the information on the control track is read (S9), and it is determined whether or not the information on the control track could be normally read (S10). Here, in a normal drive device,
If the disc is a normal modulation / demodulation system, the information of the control track can be normally read out. Therefore, after that, a write test is performed to end the start-up process (S1).
1). On the other hand, if the set disc is not normal, or if it is neither A code nor B code, it is determined in S6 that the modulation / demodulation method of the disc cannot be normally determined, and in S10, the control track is also determined. It is determined that the information of can not be read normally. Therefore, in this case, an abnormal state process is performed such as notifying the host computer that information cannot be recorded or reproduced (S12).

As described above, in this embodiment, predetermined data is recorded in advance on the disc in correspondence with the modulation / demodulation system, and the modulation / demodulation system of the disc is discriminated by recognizing the pattern of the predetermined data when the apparatus is started up. When confirming the modulation / demodulation method of the disk, it is not necessary to confirm the two modulation / demodulation methods of A code and B code, and only the modulation / demodulation method determined by the pattern recognition is required. Therefore, since the confirmation processing of the modulation / demodulation method of the disk such as reading the information of the control track is only required once, the time required for confirmation of the modulation / demodulation method of the disk at the time of starting the apparatus can be greatly shortened.

In the embodiment shown in FIG. 1, when the pattern recognition circuit 11 reads data from the disk 1 as described with reference to FIGS. 2 and 3, it is explained that the data is taken in in synchronization with the system clock. When the rotation fluctuation occurs in 2, the read data is not synchronized with the system clock, so that the target pattern may not be detected. Therefore, in such a case, if the read data is fetched in synchronism with the rotation synchronizing signal by using the rotation synchronizing signal of the spindle motor 2 instead of the system clock, the rotation fluctuation timing at the time of rising of the spindle motor 2 can be obtained. Can also perform pattern recognition accurately. That is, since the rotation synchronization signal is a signal synchronized with the rotation of the spindle motor 2, by using this signal as a synchronization clock, the read data can be taken in normally even if there is a rotation change in the disk, and pattern recognition is performed. It does not affect the operation.

FIG. 5 is a block diagram showing another embodiment of the present invention, and FIG. 6 is a flow chart showing the operation at the time of startup. The embodiment shown in FIG. 1 is an example in which predetermined data is recorded in advance at a predetermined position on the disc 1 corresponding to the modulation / demodulation system, and the modulation / demodulation system of the disc is discriminated by recognizing the pattern of the data. Is an example in which the modulation / demodulation method of the disc is determined by recognizing the SM (sector mark) pattern in the pre-format data of the disc. In FIG. 5, reference numeral 14 is a sector mark recognition circuit for pattern recognition of the SM recorded at the beginning of each sector of the disk 1. The basic structure of the sector mark recognition circuit 14 is the same as that of FIG. 2, and is composed of the same number of comparison circuits as the number of bits of the SM pattern, and a determination circuit for determining a target pattern based on the comparison result of each comparison circuit. ing. A selector is provided in the sector mark recognition circuit 14, and the corresponding modulation / demodulation circuit is selected in accordance with the modulation / demodulation method determined by the pattern recognition. Other configurations are the same as those in FIG.

Next, the operation of the above embodiment when the apparatus is started up will be described with reference to FIG. In FIG. 6, first, when the device is powered on (S1) and the disk 1 is set in the device body (S2), the CPU 10 controls the spindle motor drive circuit 8 to drive the spindle motor 2 (S3). Next, in the CPU 10, the sector mark recognition circuit 14 is set before the spindle motor 2 reaches a predetermined speed.
Is started (S4), and a signal from the optical head 4 is awaited. When the rotation speed of the spindle motor 2 reaches a predetermined speed, the sector mark recognition circuit 14 captures the signal read by the optical head 4 and performs pattern recognition to determine the modulation / demodulation method of the set disk 1. (S5).

At the time of this pattern recognition, the SM recorded at the beginning of the sector differs depending on the modulation and demodulation method of the A code and B code, so comparison data of sector marks corresponding to the A code and B code is prepared in advance. . Then, the comparison circuit compares the data read from the disc 1 by the optical head 4 with the comparison data of the A code and the B code, and the determination circuit determines whether the disc 1 is of the A code modulation / demodulation system based on the comparison result. It is determined whether the B code modulation / demodulation method is used. That is, when the data read from the disc 1 and the comparison data of the A code match, the disc 1 is discriminated as the A code, and when the comparison data of the B code coincides, the disc 1 is discriminated as the B code. When the signal read from the disk 1 is loaded into the sector mark recognition circuit 14, it may be loaded in synchronization with the system clock, or as described above, the spindle motor 2 may be loaded.
It may be captured in synchronization with the rotation synchronization signal of.

Next, the CPU 10 judges whether the modulation / demodulation method of the disk can be normally judged (S6),
When it is determined normally, the selector in the sector mark recognition circuit 14 selects the modulation / demodulation circuit corresponding to the determined modulation / demodulation method from the two modulation / demodulation circuits in the modulation / demodulation circuit 9 (S7). Further, the selected modulation / demodulation circuit is activated (S8), the control track information is read (S9), and it is determined whether the control track information can be read normally (S1).
0) If the data can be read normally, a write test is performed and the startup process ends (S11). On the other hand, if the modulation / demodulation method of the disk cannot be determined in S6, or if S1
When the information of the control track cannot be read normally at 0, an abnormal state process is performed such as notifying the host computer that the disc cannot be recorded or reproduced (S12).

As described above, also in this embodiment, since the modulation / demodulation method of the disc is determined by recognizing the SM pattern, the modulation / demodulation method of the disc when the apparatus is started up is performed in the same manner as in the embodiment of FIG. The time required for confirmation can be greatly reduced. Further, in this embodiment, since the SM recorded in advance on the disc is recognized as a pattern, it is not necessary to record the pattern recognition data on the disc. Although the embodiment of FIG. 5 shows an example in which the modulation / demodulation method of the disc is determined by recognizing the pattern of the SM, the present invention is not limited to this and, for example, AM
The modulation / demodulation method can also be determined by recognizing (address mark) or VFO pattern.

[0025]

As described above, according to the present invention, the modulation / demodulation method of the recording medium when the apparatus is started up is determined by determining the modulation / demodulation method of the recording medium by recognizing the pattern of the predetermined data recorded on the recording medium. The effect is that the time required for confirmation can be significantly shortened compared to the conventional method.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of an information recording / reproducing apparatus of the present invention.

FIG. 2 is a block diagram showing a specific example of the pattern recognition circuit of the embodiment of FIG.

FIG. 3 is a diagram showing a system clock and read data from a disk which is taken into a pattern recognition circuit in synchronization with this system clock.

FIG. 4 is a flowchart showing an operation at the time of starting up the apparatus of the embodiment of FIG.

FIG. 5 is a configuration diagram showing another embodiment of the present invention.

FIG. 6 is a flowchart showing an operation at the time of starting up the apparatus of the embodiment of FIG.

FIG. 7 is a block diagram showing a conventional information recording / reproducing apparatus.

FIG. 8 is a flowchart showing an operation at startup of the conventional device of FIG.

[Explanation of symbols]

 1 Disk 2 Spindle Motor 4 Optical Head 5 Linear Motor 9 Modulator / Demodulator Circuit 10 CPU 11 Pattern Recognition Circuit 12 Comparison Circuit 13 Judgment Circuit 14 Sector Mark Recognition Circuit

Claims (4)

[Claims] 1. An information recording / reproducing apparatus having a plurality of modulation / demodulation circuits for recording / reproducing information on / from an information recording medium by different modulation / demodulation methods, the recording medium by pattern-recognizing predetermined data recorded on the recording medium. An information recording / reproducing apparatus is provided with means for discriminating the modulation / demodulation method of (1) and selecting a modulation / demodulation circuit corresponding to a recording medium from the plurality of modulation / demodulation circuits based on the discrimination result of the discrimination means. 2. The information recording / reproducing apparatus according to claim 1, wherein the predetermined data is data recorded in advance in a predetermined recording area of a recording medium in accordance with a modulation / demodulation method. 3. The information recording / reproducing apparatus according to claim 1, wherein the predetermined data is preformatted data recorded in a preformatted area of a recording medium. 4. The information recording / reproducing apparatus according to claim 3, wherein the preformat data is sector mark, address mark or VFO pattern data.