| 摘要 |
<p>PURPOSE:To enhance the reliability by preventing malfunction caused by code error due to various factors including a dropout. CONSTITUTION:An address 603 generated in accordance with a block number 601 read out and sub-block number 602 is compared (606) with an expected address 604. If they coincide, a selector 611 selects the expected address. In case they do not coincide, a calculated value n is added by '1', and if the result does not reach the specified value N0, the expected address 604 is selected. However, if the incoincidence continuously occurs for specific N0 times, a C1 detection circuit 609 detects it, and then the selector 611 selects the expected address. When C1 pattern is not detected, the block number and the sub-block number read out are regarded correct, and the address correspond with them is selected by the selector 611.</p> |
