| 摘要 |
PURPOSE:To realize the protection of writing with every single face, by detecting the writing inhibition mark provided on both faces of a floppy disk through the sensor corresponding to each face. CONSTITUTION:The inhibition marks on both faces of a floppy disk are detected by the phototransistors 18 and 27 of the sensors 6 and 25 corresponding to each face. And thus the binary logic detection output obtained by the transistors 22 and 31 give a control to the AND gate 23 to which the signals are applied via the AND gates 32 and 34 the open/close of which are controlled by the surface selection signal (c) plus the signal passed through the inverter 33. As a result, the protection of writing is given with every single face to ensure an effective use of the storage area of the disk. Furthermore, the write/read can be controlled with no use of two or more of the floppy disk driving device but by selecting the protection and nonprotection of writing via a unit of the driving device and even in case both the program and the data are stored on the surface and back faces each. |
