JP2888921B2 - Disc playback device - Google Patents

Description

Description: TECHNICAL FIELD A digital signal such as a digital audio signal or map data is encoded in a predetermined format, and a digital information recording disk (hereinafter, simply referred to as a digital disk) carrying the obtained code signal is played. Also, the present invention relates to a disk reproducing apparatus for reproducing digital information obtained by decoding a read code signal by signal processing.

BACKGROUND ART An audio disc for reproducing music and a CD-RO on which map data for a so-called navigation system are recorded.
Recently, a disk device as a disk reproducing device capable of playing both the M (hereinafter referred to as a memory disk) has been developed. Such a disk playing device includes a D / A conversion circuit for converting a decoded digital signal into an analog signal when playing an audio disk.
When a memory disk is played by such a disk playing device, a digital signal is supplied to a speaker via a signal processing circuit including a D / A conversion circuit, thereby generating unpleasant noise. In order to prevent this, a mute circuit that interrupts the supply of the signal sent from the D / A conversion circuit to the next stage may be provided.

By the way, even if noise is prevented by such a configuration, supply of the digital signal to the D / A converter circuit is not stopped, and unnecessary power consumption by the conversion operation in the D / A converter circuit is continued. Will happen.

[Summary of the Invention] [Object of the Invention] An object of the present invention is to provide a disk reproducing apparatus which prevents unnecessary power consumption in a D / A conversion circuit when playing a memory disk.

[Constitution of the Invention] A signal reading means for reading an information signal by driving a digital disk to rotate, a decoding means for decoding an information signal sent from the signal reading means, and an audio signal as a digital signal sent from the decoding means A disc reproducing apparatus including a signal processing unit for performing a reproducing process as a detecting unit for detecting that a loaded disk is a memory disk, and a detecting unit for detecting the memory disk by the detecting unit. The supply of the signal to the signal processing means is stopped.

[Operation of the Invention] In the disk reproducing apparatus according to the present invention, when the loaded disk is played, when it is detected that the disk is a memory disk, the digital signal sent from the decoding processing circuit is used as an audio signal. The supply to the signal processing circuit for the reproduction process is stopped.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

In the disc reproducing apparatus shown in FIG. 1, the disc 1 is loaded on a disc drive mechanism 2 including a turntable, a clamper, and a spindle motor by a loading mechanism (not shown) including a tray which can be protruded and stored, and is rotationally driven. Information recorded on the disk 1 is read by the pickup 3 and supplied to the RF amplifier 4. The signal read by the RF amplifier 4 is supplied to a decoding processing circuit 5 after being amplified and shaped. The decoding circuit 5 demodulates the EFM signal to obtain a digital signal, and performs processing such as synchronization signal detection, subcode detection, and error data correction. The digital signal output from the decoding processing circuit 5 is supplied to a signal processing circuit 7 including a D / A converter via a signal stopping circuit 6. The signal processing circuit 7 converts the supplied digital signal into an analog signal and separates the signal into an L channel signal and an R channel signal. The L-channel signal and the R-channel signal are amplified by audio amplifiers 9L and 9R via low-pass filters 8L and 8R, and then transmitted to speakers 10L and 10R.

On the other hand, based on the sub-coat information obtained from the decoding processing circuit 5, the player controller 12 controls the mute circuit unless the playing disk 1 is an audio disk.
11 is driven to stop signal transmission from the signal processing circuit 7 to the next stage, thereby preventing generation of noise from the speaker. The player controller 12, together with the above-described mechanisms and circuits 2 to 11, is provided in a place other than the console section of the vehicle (for example, in a trunk).
And communicates with a master controller 13 including a CD-ROM decoder disposed on a console section of the vehicle via a transmission line formed of, for example, an optical cable. The master controller 13 causes the display device 15 to display image information such as map data obtained via the player controller 12 in response to an operation command from the operation keys 14.

Next, the discrimination of the disc 1 executed by the player controller 12 and the operation control of the signal stop circuit 6 will be described with reference to the flowchart of FIG. A main routine (not shown) is provided in the player controller 12.
When a command is received from the master controller 13 during execution of, the command processing routine is executed. In this subroutine, it is determined whether or not the command is an audio command (step S1).

If it is determined that the command is an audio command, it is determined whether or not the loaded disc is an audio disc (step S2). If it is determined that the disc is an audio disc, a signal relay is instructed to the signal stop circuit 6 (step S3), and the process proceeds to a main routine. On the other hand, if it is determined in step S1 that the command is not an audio command, it is determined whether the command is a memory command (step S4). If it is determined that the command is a memory command, the loaded disc is a memory disc. It is determined whether or not there is (step S5). If it is determined that the disk is a memory disk, the signal stop circuit 6
(Step S6), and shifts to the main routine. When it is determined in step S2 that the command is not an audio disc, when it is determined in step S4 that the command is not a memory command, and when step S5
If it is determined that the disk is not a memory disk, the process proceeds to the main routine.

As described above, in the disk reproducing apparatus according to the present invention, it is automatically detected whether or not the loaded disk is a memory disk, and when the disk is a memory disk, the output from the decoding processing circuit is detected. By stopping the transmission of the digital signal to the signal processing circuit including the D / A converter circuit and reducing the power consumption of the signal processing circuit, power saving of the device can be achieved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of a disk reproducing apparatus according to the present invention, and FIG. 2 is a flowchart showing the operation of a player controller. Description of Signs of Main Parts 1 ... Disc 5 ... Decoding Processing Circuit 6 ... Signal Stop Circuit 7 ... Signal Processing Circuit 12 ... Player Controller 13 ... Master Controller

Continued on the front page (72) Inventor Junichi Nishida 25-1, Nishimachi, Yamada, Kawaji-shi, Saitama Prefecture Pioneer Corporation Kawagoe Factory (72) Inventor Hitoshi Sato 25-1, Nishimachi, Yamagata, Kawagoe-shi, Saitama Pioneer Kawagoe Corporation Inside the plant (72) Inventor Kiyoshi Furukawa 25-1, Nishimachi, Yamada, Kawajie, Saitama Prefecture Pioneer Corporation Inside the Kawagoe Plant (72) Inventor Kenji Kaneko 25-1, Nishimachi, Oaza, Kawajie, Saitama Prefecture Pioneer Corporation, Kawagoe Plant (56) References JP-A-1-294276 (JP, A) JP-A-2-94166 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G11B 19/12 501 G11B 19 / 02 501

Claims (2)

(57) [Claims] 1. A signal reading means for reading an information signal by rotating a digital disk, a decoding means for decoding an information signal sent from the signal reading means, and an audio signal for sending a digital signal sent from the decoding means. A signal processing means for performing a reproduction process as a detection means for detecting that a loaded disk is a memory disk; and a detection means for detecting the memory disk by the detection means. A disk reproducing apparatus for stopping supply of a signal to said signal processing means from said apparatus. 2. A signal relay circuit provided between said decoding means and said signal processing means and for stopping signal relay when a memory disk is detected by said detection means. The disc reproducing device according to the above.