| 摘要 |
PURPOSE:To minimize the time required for data transfer within a rage where data is transmitted and received normally, by determining a transfer speed in accordance with the value to which a microprogram sets to a data transfer speed control register. CONSTITUTION:If a channel device 7 cannot follow up the transfer speed of a disc device by some cause when the data transfer speed between the channel device 7 and a disc controller 1 is allowed to coincide with the transfer speed of the disc device 8, the microprogram in the disc control 1 sets the value, which reduces the transfer speed, to the data transfer speed control register 5 before starting the retransfer from the beginning of a data block were overrun occurs. The output of the register 5 is inputted o a data transfer speed control circuit, ad data is transferred in a lower transfer speed from the next transfer time. |
