| 摘要 |
PURPOSE:To inhibit the reading or deleted data by recording a prescribed deletion pattern to a data area when a sector is deleted. CONSTITUTION:When information on a certain sector is deleted, a main controller 1 selects a deletion pattern generating circuit through a switch circuit 4 and at the same time reads a pre-format area like a writing mode. Then the controller 1 outputs the deletion flag-on data to a flag read/write circuit 9 after a desired sector is detected. At the same time, the deletion pattern outputted from the circuit is recorded on a data area following the pre-format area. Then a deletion pattern is recorded on the original record data in the data area of a deletion sector. At the same time, the deletion flag of a flag F of the pre-format area is turned on. In such a way, the data superposed with a deletion pattern is recorded on the data area of the deletion sector. Thus it is impossible to read out the original record data. |
