| 摘要 |
PURPOSE:To prevent previously the destruction of data by judging whether data is recorded in a compressed form or not on a magnetic tape and recognizing a compression mode at the time of reading the data. CONSTITUTION:On the magnetic tape 50 a recording density marker 60, an ARA marker 61, an ARAID marker 62, a data block 64, a tape mark 65, etc., are recorded. Control information such as the data block is decided from the combination of the recording position on the magnetic tape and a written track. A control information generator circuit 11 generates the compression control information 63 according to the specification of a control line 43. When a control information detecting circuit 12 detects the control information 63, it informs a processor 10 of the detection through a control line 45. The generation and detection of the control information can be made by the similar circuit for generating and detecting other control information. According to the specification from a host device the control information 63 is recorded. When it is read out, its compression mode is given to the host device, and processing is available by modifying compression and non-compression modes.
|
