| 摘要 |
PURPOSE:To ensure the control of various types of devices with an appropriate flexibility by providing the size counter, the positioning counter and the control decoder respectively. CONSTITUTION:File controller 1 consists of RAM11, ROM12 and processor 13 which memorize the parameter groups necessary for the process, and is also connected with fixed and variable magnetic disc device 14 and 15 plus floppy disc as the external devices. Furthrmore, controller 1 is connected to common bus 19 along with CPU17 and main memory 18. The following units are provided in the hardware block of controller 1: position counter 25 to show where the access is given on the tracks of file units 14-16; decoder 30 which receives the output signal from counter 25 for actuation and then decides singly the next sequence to be given; and size counter 31 which receives the outpu of multiplexer 29 to recognize the positions on units 14-16 respectively. With these units, the control program of ROM12 can be shared regardless of the types of the file units. |
