| 摘要 |
PURPOSE:To improve the detecting capability without deteriorating the error correcting capability, by constituting so that decoding of an external code is controlled by main and auxiliary pointers. CONSTITUTION:When decoding a double encoded data having an external code and an internal code, at least an error is detected by the internal code, a main pointer 10 corresponding whether an error exists or not is generated, and by using this pointer 10, at least an error is corrected by the external code. Subsequently, by a decoding circuit 5 of the internal code, at least one kind of auxiliary pointer 11 which is different from the main pointer 10 and shows whether detection and correction of an error are allowed or not is generated, and decoding of the external code is controlled by the main and auxiliary pointers 10, 11. |
