JPS6271060A - Reproduced data transferring device for disk record reproducing device - Google Patents

Abstract

PURPOSE:To perform data transfer which is completely free from wasteful time to host computers having any data transferring speeds by using a small- capacity buffer RAM, by providing a pickup movement controlling means which slightly moves a pickup in the direction opposite to the pickup moving direction at the time of reproduction and a waiting means which interrupts the writing to a memory means. CONSTITUTION:The current position of a pickup 17 is moved to a position slightly before an address which is the object of searching. The value of the address which is the object of searching is written in a data processing address written in a program RAM 24 and the data processing count is set at a desired block number and its value is also written in the program RAM 24. The value of a header address written in a decode RAM 43 is read out from a header detecting circuit 44 and transferred to a buffer RAM 47. Then a data transfer request is transmitted to a host computer 49. Then '-1' is added to the value of the data processing count written in the program RAM 24. When the data processing value becomes '0', all data transfer is completed.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a disc record playback device using a CD (optical compact disc) system, and in particular, to a disc record playback device using a CD (optical compact disc) system, and particularly to a disc record playback device that uses a CD as a recording medium to record an audio signal in place of an audio signal. The present invention relates to a reproduction data transfer device for reproducing digital signals such as programs and data and transmitting them to the outside.

[Technical background of the invention]

Currently, among audio equipment, there is a digital disc record playback device that uses the CD system to realize high-density recording, high-fidelity playback, advanced control functions, and excellent operability. This CD system consists of a 12-diameter transparent resin disk covered with a thin metal film that forms 9 bits (irregularities with different reflectances) corresponding to digital PCM data, and a disk with a constant linear velocity (LVC). The CD system was originally designed to play back music with linear tracking from the inner circumferential side to the outer circumferential side using an optical pickup with built-in semiconductor and photoelectric conversion elements. The purpose is to play back signals, but recently, VC has been introduced to the market due to its huge recording capacity (about 1 hour of information in stereo playback for music signals).
Rather than using the music signal recording area of a CD as a digital information recording area, the CD-R, OM (read-only memory) system, which is used as a read-only data recording medium, has been considered. This method does not change the CL' recording and reproducing format for music signal reproduction, but adds a new format to record and reproduce digital information using the music signal recording area.

Therefore, in the conventional CD system for music signal reproduction, 2
4 channel (L-ch, R-ch) analog signals
4.1KH71 and recorded as 16-pit digital PCM signals, but the above C
In the D-°ROM method, as shown in Figure 7, the 16
Divide the bit into 8 bits (1 byte), 2352
Data is recorded in units of bytes (1 block). As shown in the figure, its configuration is as follows: (a) Synchronization pattern (12 pies) for recognizing the start of a block)
, (b) Block address information (4 bytes, 1.”
ys seconds) (hereinafter referred to as header address), (C) Data used by the user (2048 bytes = 2 bytes), (d) Data for detecting and correcting data errors (288 bytes) Small It will be.

Here, the data in (d) above is a CD for playing music signals.
C1 in the recording/playback format. C2 parity correction is used when errors cannot be corrected by correction alone, and the error rate is ultimately improved to 10-12. Therefore, if we look at the error rate.

It is quite possible to use CI)-ROM type disks as data recording media for computers and computers.

Furthermore, one block in the CD-RO+V system corresponds to one frame of subcode data (address data) in the CD system, and is reproduced every 1/75 seconds. Therefore, since the user data is 2 bytes/block,
CD-ROM data transfer rate: approx. 75X 2
K = 150 to pa() /see,! : fk le.

Therefore, if you record one hour on a C'D-ROM disc, it is possible to record 150KX60\60 = 540M bytes of information.The recording capacity is equivalent to 500 to 1000 ordinary floppy disks Or approximately (capital) for a document with 2000 characters per page.
Equivalent to 5 + trap. For this reason, CD-R.

The OM method has a larger recording capacity than existing disk-type recording media, and as mentioned earlier, it is a book that realizes a data recording medium with a Kg error rate. Therefore, it is difficult to actually use the CD-ROM method as described above. In this case, since a disc on which data is recorded in the CD-ROM format is simply an information recording medium, a CD-ROM disc record playback device for reproducing the information and a host system (for requesting and processing the information) are required. (Hoss side comviator) is required. That is, similar to data processing by a normal computer, the host combiator transfers a predetermined command to the disc record playback device according to keyboard operations, the playback device searches for the desired address in response, and after the search is completed, the same command is sent to the disk record playback device. The user data reproduced by the reproduction device is transferred to the host computer, and the host computer processes the user data.

[Problems with background technology]

Here, the data transfer speed of a CD-ROM type host computer varies depending on the host computer used, and most of them are lower than the data transfer rate of a CD-ROM type disc record playback device. . Therefore, it is necessary to provide a buffer memory for data transfer within the CD-ROM type disc record reproducing apparatus.

However, the capacity of the buffer memory that can be used in the disc record playback apparatus cannot be made very large in order to reduce the manufacturing cost of the playback apparatus. Furthermore, it is ideal for a CD-ROM type disc record playback device to be able to be connected to any host computer, and for this purpose it is desirable to make the data available on the host computer. ga°
It was also a challenge.

[Purpose of the invention]

The present invention was made in response to the above-mentioned technical requirements, and uses a small-sized buffer memory to connect externally connected devices with various data transmission speeds, such as the above-mentioned host converter. The purpose is to provide a good data transfer device for users.

[Keystone of invention]

The playback data transfer device for a playback device of a disk record playback device according to the present invention has a basic configuration as shown in FIG. A memory control means that controls writing of data to the memory means and also controls reading of the written data 't--sequentially transferring it to the outside, and a judgment that determines whether new writing to the memory means is possible. a pickup movement control means for slightly moving the pickup in a direction opposite to the direction of movement during playback based on the determination result; and a pickup movement control means for slightly moving the pickup in a direction opposite to the direction of movement during playback based on the determination result; and a standby means for suspending writing to the memory means until the readout is completed.

[Embodiment of the Invention] An embodiment of a reproduction data transfer device for a CD-ROM disc record reproduction device to which the present invention is applied will be described with reference to the drawings.

First, FIG. 2 shows the electric circuit system of this embodiment.

In the figure, the control circuit Uυ includes a microcomputer, an interfunicipal circuit, etc., receives commands by operating the keys of the key switch group αa, and sets each part to a predetermined state according to a program stored in a program ROM (13). Therefore, during playback operation, the control circuit aL1
The disc motor 19 and the pickup feed motor αe are driven by the control signal from the disc playback system 1# circuit a, and when the laser diode of the pickup (I?) is turned on, recording is performed on the disc α. The data is read out by the pickup 11η) and the signal t
- This RF detection circuit (1
1 amplifies the supplied signal and separates it into a signal supplied to the servo circuit ■ and an EFM signal supplied to the EFM demodulation circuit (211. Here, the servo circuit ■ is the pickup 17)
In addition to transmitting signals for applying focus servo and tracking servo to the disc reproduction system control circuit Q4), in combination with the control signals of Rikishima et al., it performs linear tracking servo on the pickup feed motor Oe, and - A signal is also sent to data L9 to control the CLV servo.

In addition, the 73 FM demodulation circuit 01) is regenerated and the 9 EFM
Waveform shaping the signal and F! FM demodulation is performed, and subcode data (8-bit data consisting of subcodes r to W) is generated from this.
Separate the synchronization signal that becomes the subcode Q detection circuit Then, the sub code Q address data detected by the sub code Q detection circuit @ is stored in the TOC (Table of Contents) in the lead-in area.
In the case of data, the program RA is
It is taken into M(2) and used for rounding to set the target address of the search operation, and if it is program area data, it is input to the control circuit aυ and used to recognize the playback position, as well as the display output control circuit (to). It is used to display the necessary information on the display section (to) through the display section. In addition, the audio signal input to the D/A conversion circuit (to) is returned to an analog signal and subjected to necessary error correction, correction, etc. processing, and then used to drive the speaker (5). It will be done.

The circuit system explained so far is the conventional CD method (7)
It is realized by the same equipment as the digital record reproducing apparatus, and by adding the circuit system described below to the circuit, an hcD-ROM741 type disc record reproducing apparatus is constructed.

In Fig. 2, the playback signal sent out from the EFMFM demodulation circuit C is processed by the synchronization detection circuit (4ρ and unscrambler (6)) if it is recorded instead of an audio signal and is a signal such as a program or data. Therefore, the synchronization detection circuit μυ detects the synchronization pattern (a) shown in Fig. 7, and the arescrambler ■ descrambles it according to the prescribed rules, and the synchronization pattern shown in Fig. 7 is output. The data for the indicator block is supplied to the decode RAM (c).The header address in the l block is detected by the header detection circuit (A4) and supplied to the control circuit αυ.

And made! The head address input to the control circuit αυ is used for the search operation in the same way as the subcode Q address. On the other hand, the data written to the decoder RAM 143K is subjected to a predetermined error detection process, and if an error occurs, the control circuit αυ sends the data to the RAM controller (t
Error correction is performed using a 0eV error correction circuit and an error correction circuit of 0eV. Therefore, after the error correction is completed, the decoder RAM
(The data in 43 is taken into the buffers R, AM (4η). However, all the data in the decoder RAM is not transferred, but the control circuit (11J is Only the user data shown in (C) is transferred to the buffers R and AM (471).

After all the desired data is written to the buffer RAM (4η), the control circuit is connected to the host computer (41) via the host computer interface (4).
Outputs a data read request signal to When the host combiner +41 completes preparations for reading data, it outputs a predetermined signal to the control circuit all via the host combiner interface (4I3), and after receiving the signal, the control circuit αυ uses the RAM controller e4t-. The user data in the buffer RAM (4η) is transferred to the host computer (41) via the host computer interface (41).

In addition, it is possible to control the disc playback system by supplying predetermined commands to the control circuit according to selective operations of the host computer (41 is a keyboard) 50. Note that this system normally operates according to commands from the host computer. If it works but the host computer is not connected, you can use the key switch A2 to perform simple operations. However, in consideration of the case where the host computer 4 is not connected, the configuration is such that a simple display is displayed on the display section.

The CD-R and OM systems, as achieved by F*, are realized not only by operating the playback device that plays back the disc, which is the data recording medium, but also by connecting the host system that processes the played data. It is something. The operation of the system to which a dedicated computer is connected as the host system is as follows. First, when the keyboard 6υ of the host comviator 4 is operated, it turns the host computer interface 4 and connects the control circuit 1
A search operation command specifying a header address or TNO (track number indicating a song number, etc.) is input. Then, the control circuit αυ starts the disc playback system control circuit (I-pickup αυ) based on the designated search target address and the current address where the big pickup αη is currently located.
Instruct D to move (kick motion). And pickup CI? ) is sent to just before the search target address, the control circuit αυ stops the kick operation and decodes T.
It waits until one block of data indicated by the desired header address is stored in I, A M +43, and transfers the data to the host computer (41) via the host combinator interface (c) to perform the search operation. end.

Here, in the CD-ROM system, as mentioned above, 1
Consider the case where the user data of the block is 2048 bytes C2) and the host combinator 141 requests this amount of data.First, the control circuit αD
After recognizing that the data indicated by the desired header address has been stored in the decode RAM+43 through the above search procedure, the RAM controller 09 supplies a signal to the RAM controller (4I3) to stop the subsequent write operation. The desired data will be held in the decode RAM 143 until a write restart signal is supplied to the host combiator (c), and the host combinator (c) can read the data at any read speed. Buffer R, A M (47) shown in the figure
becomes unnecessary. However, as data, CRTci3
When image data to be displayed is recorded, the storage capacity is normally 128 bytes, and the screen will be displayed with 128/'2 = 64 blocks of data.

Therefore, in a system not provided with the buffer RAM (47), it is necessary to repeat the above reading procedure 64 times.

If such a method is used, the procedure for reading several consecutive blocks of data on the disk will be as follows. 9. The situation is shown in FIG.

tJ control circuit (111 is the Nth desired block A
After recognizing that the data has been stored in the decode RAM controller 43, the RAM controller (4) supplies a signal instructing to stop the subsequent write operation, and sends a data read request to the host computer f41.

It) Since the above write stop signal is supplied,
The data of the next N+1 block B is decoded by RA
M (41K cannot be stored. Therefore, the control circuit (ill) returns the next data KO!, returns the pickup αη one track (one rotation) on the disk (to point 0), and enters a waiting state.

1it) After a data read completion signal is transmitted from the host convenience store, the control circuit (II) supplies a write permission signal to the RAM controller Vie. As a result, after the pickup αη moves to the starting position of the next block B, new playback data is stored in the decoding RAM+43 again. Hereafter, steps 1) to m)
repeat.

That is, according to this method, every time one block of data is read, the pickup αη in the inner circumferential direction of the disk is
A waiting time for one revolution of the disk is required as the track becomes harder. Here, the time for one rotation of the disk α is about 125 m5ec on the inner circumference and about 300 m5ec on the outer circumference, so in order to read the data of 64 blocks recorded on the outer circumference, it takes 0.3 x 64 = 19.2 It takes several seconds. If it takes that much time to read one screen worth of data on the CRT 153, it is practically inconvenient.

For this reason, in addition to the decode RAM (43), it is necessary to provide a buffer I-1, AM (47) for storing data to be transferred to the host computer (c).

Therefore, the operation when a buffer RAM (4η) is provided is as follows.Furthermore, the state of reading/writing is shown in FIG.

1) After the control circuit αυ is unaware that the data of the Nth desired block has been written to the decoder AMI 43, it writes the data to the buffer RAM (477) using the RAM controller (c) and the loop. Sends a data read request to the host combinator (4).

1.) Buffer RAM (data reading/writing can be performed through S, and the control circuit αD stores the data in the decode R, AM t43 every time the subsequent block of data is stored in the decode R, AM t43. are written to the buffer RAM (QK sequentially.

1it) Host combination 2-41 is buffer aAM
The read operation continues as long as data remains in j47), and ends after reading data for the desired number of blocks.

Now, consider the capacity required for the above buffer AJ4η.

First, it is assumed that the data reading speed of the host combiator i41 is faster than the data reproducing speed. That is, CD-IL
Assume a host combiator α■ equipped with special software capable of transferring data at a data transfer rate of 150 bytes/sec or more using the OM method. In this case, the host combinator Ql uses the buffer AM147) iciF.
The written Nth block data is decoded by the next N+1st block data.The RA speed is L lower than that of the CD-ROM system (<1 soK byte, '5ea). Therefore, at the time when the control circuit a11 attempts to write the N+th block into the buffer RAM (471K8), the host convenience store (49) is still reading the Nth block data from the buffer RAM (4η). Therefore, it is necessary to provide several stages of partitions R, A M (471) depending on the difference in data transfer speed between the two.For example, depending on the data transfer speed, bytes/se
When a host combination of c is used, the difference in data transfer speed with the playback side is 150-5-Q[=100 bytes/sec. That is, 1 second disk (l1%I
When playing, the buffer RAM (100K for 4η)
Bytes of data will be left behind without any slippage.

Therefore, the previous 128 bytes (64 blocks XI/”7
5 seconds worth of data), (150
A buffer RAM (47) with a capacity of 100 K) x 64 x 1/75 = 85.3 bytes is required. Of course, if the transfer speed of the host computer nl is lower than this, or if the data transfer capacity is larger than this, larger capacity buffers R and AMt are required.
However, the capacity of buffer RAM (4η) is limited, and in order to reduce the manufacturing cost of the playback device, it is necessary to use buffer RAM (4η) with as small a capacity as possible. Furthermore, it is desirable for this system to be able to connect to any host computer 4 with different data transfer speeds.
If it is a part-time job/5ec), then the above idea is worth 1 second! l) (150-X) (K bytes) of data will gradually be left unread in the buffer R, A M (47). Here, as shown in FIG. 5, if all the data in the buffer RAMPη is left unread (buffer full state), the address at that point P is memorized, and the address at that point P is picked up (I? )
A system that moves one track toward the inner circumference (to position q) and does not write to buffers R, A-M (47) until the stored address is reproduced again (to position p). think of. In other words, the host computer (41K
This is a system that reads simulated data. Thisζ
If the time for one rotation of the disk a81 is y (Sec), the data capacity read by the host computer (41) is XXYCK bytes during one rotation of the disk α barrel. Therefore, by making the data capacity left in the buffer AM board equal to the XXYCK bytes of the upper 5C, data transfer can be performed with a small memory capacity and no waste of time. That is, Pella 7 ArLA M (47) 6! ') Capacity Z=xXy
(K bytes). Here, since it is assumed that X≦1501 (byte/5ee), the maximum capacity of Z is when X=150 (Kbyte/sec). And x=150 (K bytes/sec) is C
Since the data transfer speed is the same as that of the DP and OM methods,
The buffer R, A M +47) should have a data capacity equivalent to one revolution of the disk.

In other words, the maximum value of y is Y:= 0.3(sec
), then Z = 150X 0.3=45
CK Byte)'s par j aa R A M (471 is enough -j--h -1μ +1M 1 misery
Miso P1. / f/ φ) 1 no---＼ 1 l
- If a host combiator (41) is used, buffers R and A with a capacity of 2 (K bytes) as described above.
M (47) is sufficient, so in the end, the buffer RAM M 1
47) has a data capacity equivalent to one revolution of the disk, it is possible to perform good data transfer to all host combinators having various data transfer speeds.

Based on the above, the data transfer operation of this embodiment will be specifically explained. The control is performed by a microcomputer in the control circuit συ, and the program R
OM (operates according to the data transfer operation execution program written in u3).

Here, the flowchart is shown in FIG. 6, and the following description will be made along this flowchart.

Step ■> When the keyboard r51) of the host computer +41 is operated and a search operation command is input to the control circuit 0υ, the process proceeds to the following step.

Step ■> Receive the search target address and the required number of blocks, that is, the number of blocks for one screen, etc. requested by the host combiator (II) via the set combinator interface Step ■〉 Write and memorize in M.241 Specified search target address and current pickup (
Based on the current address where 1η is located, instructs the disc playback system control circuit α (to move the pickup (IT),
Perform a kicking motion 0 Repeat the kicking motion several times,
The current position of the pickup aη is moved to a position slightly before the search target address.

<Step ■> Program ratio A Write the value of the search target address written to the program RAM in step ■ to the data processing address written to MQ4, and similarly set the data processing count to the required number of blocks above. Write the value to the program (To).

<Step ■> Decode R, A, M (Read the value of the header address written in i3 via the header horizontal circuit (44).

<Step ■> Current header address and program ratio AMC read in step ■! Steps ① and ② are repeated until the data processing addresses written in 41 become equal.

<Step ■> Decode r (All user data in A M +43 is buffered RAM Q + ηKRAM controller (4
The data is transferred using the transfer file 61.

Step ■> Send the data transfer request to the host computer interface (
41 to the host combiator (4I).

Step ■> The value of the data processing count written in the program ratio AM (24) is decremented by 1. When the value becomes 0, all data transfer is completed. 0 <Step [phase]> Program RAM 124) Add 1 to the data processing address D value written in K$. That is, the data processing address is rewritten to the next block address to be processed.

(Step ■) Currently, it is determined how much data remains unread in the buffer A M (47). If all data remains unread (buffer full state), proceed to the next step, otherwise step
Return to

<Step ■> Move the pickup αη one track in the inner circumferential direction, and return to the input step ■ after one rotation of the pickup αη.

By executing the above operating procedure), this embodiment uses a small-capacity buffer RAM (in other words, a host computer with any data transfer speed (41K), with no waste of time at all). Data transfer can be performed.

Although one embodiment has been described in detail so far, the present invention is not limited to the above-mentioned embodiment, and various modifications are possible and a wide range of implementation means are permitted.

〔Effect of the invention〕

As explained above, the playback data transfer 22 of the disc record playback device according to the present invention uses a small-capacity buffer memory and is good regardless of the data transfer speed of the externally connected device; one data transfer can be performed. It is possible.

[Brief explanation of drawings]

FIG. 1 shows a configuration V showing the basic configuration of the present invention. FIG. 2 is a block diagram showing a t-circuit system in an embodiment of the reproduced data transfer device for a disc record playback device according to the present invention, and FIGS. 3 to 5 are diagrams for explaining the entire operation of the embodiment. An explanatory diagram, FIG. 6 is a flowchart showing the operation procedure of the same embodiment. FIG. 7 is a C to which the present invention is applied.
FIG. 3 is a diagram showing a data format of the D-ROM system. DESCRIPTION OF SYMBOLS 11... Control circuit, 14... Disc playback system control circuit, 17... Pickup, 18... Disc. 43... Denid R, A M. 45, 50... RAM controller, 47... Buffer RAM. 49...Host computer. Agent Patent Attorney Noriyuki Chika Yudo Hiroshi Uji Figure 1. Figure 3 Figure 4

Claims (2)

[Claims] (1) A disk record playback device that uses an optical pickup to read data from a rotating disk on which digital data has been recorded, includes a memory means for temporarily storing the read data, and a memory means for temporarily storing the read data; On the other hand, there is a memory control means which performs writing control of the data and read control for sequentially transferring the written data to the outside, and a memory control means which performs read control to sequentially transfer the written data to the outside, and a memory control means which checks whether there is a writable capacity remaining in the capacity of the memory means other than the unread portion. a determining means for making a determination; a pickup movement control means for slightly moving the pickup in a direction opposite to a moving direction during reproduction based on a determination result of the determining means; and a pickup movement control means for slightly moving the pickup by the pickup movement control means. A reproduction data transfer apparatus for a disc record reproduction apparatus, comprising: a standby means for suspending writing to the memory means at least until the pickup returns to the starting position of the minute movement. (2) The capacity of the memory means is set to be approximately equivalent to the amount of data reproduced per one rotation of the disk, and the amount of movement of the pickup by the pickup movement control means is set to correspond to the track pitch of data recorded on the disk. Claim 1 characterized in that it is a distance.
A playback data transfer device for a disk record playback device as described in 2.