| 摘要 |
PURPOSE:To make the omission of the retransfer of normal transfer end blocks possible at the up date processing by so controlling the data transfer that a retry start point is renewed every time when the transfer for one block ends normally. CONSTITUTION:A register 4 storing control parameters for data transfer of plural blocks, and a register 5 for holding the parameters at the start time which saves the contents of the register 4 prior to starting of the data transfer for one block are provided to a control device which fetches and holds the parameters for controlling data transfer based on the command of a host device and controls the transfer through lower devices. Also, a renewing part 6 for the contents of the register 5 based on the normal execution of the data transfer for one block and a set circuit part 8 which sets the contents of the register 5 in the register 4 by the instruction of the part 7 at the non-normal end of the data transfer for one block are provided, and at the time when an up date reguest occurs, the retry is carried out from the top position of the data transfer for one block by the instruction of the part 7. |
