PURPOSE: To improve the processing efficiency by reading data from an external memory device, storing it in a memory and writing this data in the other external memory without using a general-purpose bus.
CONSTITUTION: When it is judged that the write operation of all the prescribed data in a magnetic tape device 5 is terminated, the effect is reported to a host processor 1, and a series of processing operations is completed. When the data is transferred from a fixed disk device 4 as the external memory to the magnetic tape device 5, the general-purpose bus 6 is occupied only during the transfer of the instruction and the termination of the processing. Since the general-purpose bus 6 is not occupied while the data transfer is executed, which requires the longest time, the host processor 1 can execute the other operations during the data transfer. Therefore the processing efficiency can be improved as a whole.
HAGINO KAORU
KAMIYAMA KAZUHIDE
YANO HIDETO
