| 摘要 |
PURPOSE:To elevate the bit rate of a buffer by designating an address range of a data on the disc equipment, and allowing to use the buffer to only a data in said range. CONSTITUTION:When a request address is in the range disignated by the register 2 containing the upper limit value of address and the register 3 containing the lower limit value, and it is registered in the register group (BAA)8, a data is read out from the disk buffer. If it is out of the range, a regular disc access operation is executed by an output signal 32 of the inverter 7. And, even if it is out of the range, in case when a control signal 12 showing that it is not stored in the disc buffer is provided as an output of the AND circuit 11, a data is derived from the disc equipment by the signal 12, and after that, a block containing said data is stored in the disc buffer. Also, the contents of the BAA8 are stored, as well. Furthermore, the contents of the BAA are also updated. In this way, only an effective file of the disc buffer can be selected, and an efficient processing is made. |
