| 摘要 |
PURPOSE:To enable an issuer of a write instruction to protect the stored information by each of stored units selectively, by writing the information of plural bits for deciding whether writing in the storage units can be made or not in part of the ID parts of the respective storage units. CONSTITUTION:A storage unit having a specified length is constituted of a gap part, an ID part and a data part. Part of the address information of sectors, the information indicating the state of tracks, and the information for checking the effectiveness of write information are included in the ID part. The series signal read out from a magnetic face is paralleled with a series/parallel converting element 28, and the parallel signals are stored in an RAM20 and are inputted to one input terminal of a comparator 8. On the other hand, the control signal which had been received from a processing unit before the starting of the reading out in the ID part and has been latched in a latching circuit 16 is applied to the other input terminal of the comparator 8. The control signals from the ID part which has read the information therein and from the processing unit are compared over the entire bit. |
