| 摘要 |
PURPOSE:To correctly read data even when a synchronizing signal cannot be detected due to the cause such as a drop-out by controlling the reading timing of the data of a card with a synchronizing signal detecting pulse or an interpolating pulse. CONSTITUTION:In the track of an optical card, a synchronizing signal and data are recorded. The output from a line sensor 14 to reproduce the optical card is binarized 21, and supplied to a PLL circuit 22 and a DFF23. The output of the FF23 is supplied to an AND circuit 24 and supplied to a shift register 25. The output of the register 25 is supplied to a digital comparator 26, a synchronizing signal detecting pulse PSY is supplied to a gate pulse generating circuit 27 and supplied to a NOR circuit 28. The output of the circuit 28 is supplied to a synchronizing counter 29 which is an interpolating means and supplied to the circuit 27. An interpolating pulse PH is synchronized to the pulse PSY, the circuit 27 cannot detect the pulse PSY, and even then, a correct gate pulse PG can be generated.
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