| 摘要 |
PURPOSE:To realize a code suitable for high-density recording with a simple circuit by applying 7/8 conversion to a high-order 7 bits of the 1st data word of 16 bits by two data works of 8 bits and applying 9/10 conversion to 9 bits by the 2nd data of 8 bits. CONSTITUTION:A code word transmitted from a ROM104 or 105 is fetched by a parallel/serial converter (P/S)108, converted into a bit string and transmitted to an exclusive OR109. On the other hand, an inverse control circuit 110 calculates a select code SC based on a DP and F of a code word transmitted from the ROM14 or 105, a value of an integration value DSV up to the final bit LB of a preceding code word stored in an inverse control circuit 110 and an output LB of a D flip-flop 111 storing the final bit of the preceding code word transmitted, transmits the result to an exclusive OR109 to decide whether the codo word is brought into a back pattern or not. Thus, the DSV is controlled for both the 7/8 and 9/10 conversion. |
