| 摘要 |
PURPOSE:To shorten a time required for a signal processing, by controlling an optical head driving motor by detecting a service code after performing EFM demodulation and sending a detected result immediately to a microcomputer, and controlling the position relation of an optical head to the track of a CD. CONSTITUTION:A signal obtained via the optical head 103 and recorded on the CD 101 is amplified by an RF(Radio Frequency) amplifier 105, and is demodulated by an EFM (Eight to Fourteen Modulation) circuit 106, and is sent to a DP(Data processor) 107, and also, the output of the RF amplifier 105 is sent to a driving motor 104. Meanwhile, the signal is sent from the EFM 106 to a PLL 1, and is sent to a header recognition circuit 2. Furthermore, a block address identified at the header recognition circuit 2 is sent to a CPU 3, and controls the driving motor 104 of the optical head. Thus, since a dedicated route is provided in the control circuit of the driving motor of the optical head, a processing time can be reduced.
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