JPH07122958B2 - Compact disc high-speed access device - Google Patents

Description

The present invention relates to a high speed access device for a compact disc including a CD-ROM.

(Prior Art) In recent years, compact discs (hereinafter referred to as CDs), which have been developed for high-fidelity audio, have a CD-ROM containing information other than music, such as character information and graphic information, due to its enormous storage capacity. It has been widely used in information equipment such as.

FIG. 2 is a block diagram showing an example of a conventional CD access device, 21 is a linear velocity control device that constantly controls the CD at a prescribed linear velocity, and 22 is stored in the CD rotating at the prescribed linear velocity. The data reading device for reading the stored data, 23 is a system control device, which uses the elapsed time code recorded as the time code on the CD read by the data reading device 22 described above, so that the data is read at the required position on the CD. The data reader 22 is controlled so that the optical pickup moves.

In the CD access device thus configured, the system controller 23 first moves an optical pickup (not shown) provided in the data reader 22 in the radial direction of the CD to record on the CD including the position to be accessed. Get closer to the truck.
After that, the linear velocity control device 21 reads the elapsed time code of the CD rotating at the specified linear velocity, and reads the data reading device 22.
Read and output to the system controller 23. The system controller 23 controls the data reader 22 to move the optical pickup to the track to be moved more accurately by using the elapsed time code. After the optical pickup reaches the recording track on the target CD, waits for the CD to rotate until the position to be accessed reaches the position of the optical pickup. Causes 22 to output data.

(Problems to be solved by the invention) However, in such a conventional access method, the CD
The position on the recording track where the optical pickup should be accessed after the optical pickup reaches the recording track that includes the time required to read the elapsed time code included in the recorded data of However, there is a drawback in that the time required to reach is restricted to the specified linear velocity of the CD, which affects the access time.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional drawbacks, and an object thereof is to provide a CD high-speed access device in which the access time is not restricted to a prescribed linear velocity.

(Means for Solving the Problems) In order to eliminate the above-mentioned drawbacks, the present invention provides a linear velocity control device capable of controlling the linear velocity at a constant linear velocity even when the CD has a linear velocity higher than a prescribed linear velocity. Structure comprising a data reading device capable of reading CD data even at a linear velocity, a data storage device for temporarily storing the data read by the data reading device, and a system control device for controlling each of the above devices To solve.

(Operation) According to the present invention, since the CD is rotated at a high speed and accessed by the above configuration, the access time can be shortened, and the information equipment using the CD-ROM can be made extremely effective. You can

(Examples) Hereinafter, the present invention will be described in detail with reference to the drawings by examples.

FIG. 1 is a block diagram of a compact disc high-speed access device showing an embodiment of the present invention. In the figure, 11 is
A linear velocity control device capable of controlling the CD at a prescribed linear velocity at a constant rate and controlling the rotation at a constant high linear velocity different from the prescribed linear velocity at a constant rate, 12 is a data reading device, While rotating at the above specified linear velocity, other than that,
It is possible to read the data recorded on the CD even during the rotation at the high linear velocity including the other high linear velocity. Further, 13 is a data storage device, and a data reading device 12
The data read by is stored temporarily and the blank of the data is embedded when the rotation of the CD shifts from the high speed to the specified linear velocity. Further, 14 is a system control device, which instructs the linear velocity control device 11 to rotate the CD at a specified linear velocity or at a high linear velocity, and further, the elapsed time of the CD read by the data reading device 12. The code is used to control the data reading device 12 so that the optical pickup moves to the recording track including the position to be accessed on the CD, and further, the writing and reading timing of the data storage device 13 and the address are instructed. .

In the present invention configured as described above, first, at the time of access, the system control device 14 drives the linear velocity control device 11 to control rotation at a constant high linear velocity. Further, the system controller 14 moves the optical pickup included in the data reader 12 in the radial direction of the CD so as to approach the recording track including the position to be accessed. Next, the data reading device 12 reads the elapsed time code recorded on the CD rotating at a high linear velocity by the linear velocity control device 11 and outputs it to the system control device 14. System controller
14 uses the elapsed time code to control the data reading device 12 so that the optical pickup moves to a recording track to be moved with higher accuracy. Then, the optical pickup waits for the CD to rotate until the position to be accessed after reaching the recording track to be moved reaches the position of the optical pickup, and after that arrival, the system controller 14 causes the data to be transferred. The reading device 12 is instructed to output the data, and at the same time, the data storage device 13 is instructed to write and read the data from the data reading device 12.

The data storage device 13 also starts reading immediately after the start of writing, and the data output from the data reading device 12 is immediately output from the data storage device 13. Data storage 13
The reading speed is read at the speed read by the data reading device 12 when the linear speed control device 11 rotates at a specified linear speed.

Therefore, when the data storage device 13 is rotated at a high linear velocity, the amount of data written to the data storage device 13 is larger than the amount of read data, so that data is gradually accumulated. When the data reaches a certain amount, the system controller
The reference numeral 14 stops writing in the data storage device 13, and thereafter changes the linear velocity control device 11 and the data reading device 12 to the control of the prescribed linear velocity, and also controls the radial direction of the optical pickup included in the data reading device 12. Also stop.

The data reading device 12 cannot read data until the control of the linear velocity control device 11 stabilizes at the specified linear velocity. After the linear velocity control device 11 stabilizes at the specified linear velocity, the system control device 14 determines the data read by the data reading device 12 in the same manner as in the case of the high linear velocity described above, and this time, the data storage device 13 The optical pickup included in the data reading device 12 is moved to a position before the last data written in.

Then, wait for the CD to rotate until the data reading device 12 reads the last data, and the data storage device
The writing in the data storage device 13 is restarted at the position where the data stored in 13 and the data read by the data reading device 12 are continuous. After the restart, the writing speed and the reading speed are the same, and the data storage amount does not change and the data storage device 13
There is no need to exceed the capacity of or to run out of data.

Since the amount of data accumulated in the data storage device 13 when rotating at a high linear velocity is made larger than the amount of data blank generated when changing to a specified linear velocity, the data storage device 13 The output data will not be interrupted.

As described above, the present invention eliminates the blank space of data when the linear velocity control device 11 controls the CD at a constant linear velocity by a linear velocity higher than the prescribed speed at the time of access, and when returning from the high velocity to the prescribed normal linear velocity. By providing a data storage device for this purpose, high-speed access is possible without being restricted by the prescribed linear velocity of the CD.

(Effects of the Invention) As described above, the present invention provides a linear velocity control device that constantly controls a CD at a linear velocity higher than a normal prescribed linear velocity, and a high-speed linear data storage device capable of temporarily storing data. In order to eliminate the blank of data when shifting to the specified normal linear velocity,
By providing a data storage device, the CD
It is possible to access at high speed without being restricted to the normal linear velocity.

[Brief description of drawings]

FIG. 1 is a schematic block diagram of an apparatus showing an embodiment of the present invention, and FIG. 2 is a schematic block diagram showing a conventional apparatus. 11,21 …… Linear velocity control device, 12,22 …… Data reading device, 13 …… Data storage device, 14,23 …… System control device.

Claims (1)

[Claims] 1. A linear velocity control device capable of constantly rotating a compact disc at a predetermined prescribed linear velocity and a linear velocity higher than that, and a linear velocity prescribed by the compact disc and a high linear velocity. A data reading device that can read the data stored in the compact disc even during any rotation of the speed, a data storage device that temporarily stores the read data, and a linear velocity that regulates the compact disc. , Or at a linear velocity higher than that, the linear velocity control device is instructed, and the elapsed time code of the compact disc read by the data reading device is used to determine the position of the compact disc to be accessed. Control the data reader so that the optical pickup moves to the recording track that contains it, and And a system controller for instructing the timing and address of writing and reading to and from the data storage device, wherein the system controller stores the data stored in the data storage device when the compact disc rotates at a high linear velocity. By controlling the data reading device and the data storage device so that the data to be stored after the change to the specified linear velocity is continuous, the rotation of the compact disc changes from the high linear velocity to the specified linear velocity. A compact disk high-speed access device characterized by interpolating a blank of data that sometimes occurs.