| 摘要 |
PURPOSE:To shorten the copy time by reading and writing plural pieces of record information from plural heads to plural records having identical cylinder and record number by means of a start instruction to the own system disc. CONSTITUTION:An SIO instruction 4 for disc read by plural heads (HH=1-l) is transmitted to a channel 2 from a central controller 1. After the reception of device end representing the end of read command start to each head, the channel 2 transmits read commands 15-17 to each head to a disc controller. Data of HH=1-l are transferred to a main memory via a disc controller buffer memory independently by using the read command. Then the data is written in l-set of records till HH=1-l having the identical cylinder and record number according to the command sequence similar to that at read. |
