| 摘要 |
PURPOSE:To independently carry out plural sub-channel input and output controls by referring to a sub-channel information area in a sub-channel memory and controlling a channel to require no management for the busy state of the channel. CONSTITUTION:Input and output starting instructions outputted to a channel device 10 from a CPU includes function information indicating a processor communication, an input and output instruction type code, a channel number, a sub-channel number and a sub-channel control information address, which are respectively set to input and output registers 21, 22, 23. A sequence circuit 31 sets a memory address corresponding to the sub-channel number to a register 32 based on the function information. Then, response information indicating that the input and output starting instruction is received is set to the register 23 and the information is transferred to the CPU through a system bus 14. Thereby, the input and output starting instruction from the CPU can be received even during the process of other input and output starting instructions. |
