| 摘要 |
PURPOSE:To improve the efficiency of read access by recording a data by dividing it into plural small areas and adding a mark to identify its data area to each data area. CONSTITUTION:In expressing a data in several bits or several tens of bits, e.g., per one column and arranging the data in a line, the data is expressed by a suitable code, e.g., an MFM code, and 1-bit of data is expressed by 2-bit of the MFM code. Since 16-bit is used for one line in the MFM code, 8-bit, i.e., 1 byte data is recorded on a line, and one data sector 6 is formed in the unit of several tens of lines each of which bits are recorded. A mark 8 is added to identify the sector 6 to the data 7 in the sector 6. Information such as a number in ascending order is recorded as the mark 8, the sector 6 is identified by reading the mark 8 at reading and mis-reading of the mark 8 is prevented. |
