| 摘要 |
PURPOSE:To restart the interrupted operation very easily, by storing the state of interruption of the transmission operation in a main storage device as a status word by a communication control part when the transmission operation is interrupted. CONSTITUTION:If a chain command indication flag is set, a communication control part 3 checks an interruption indication flag in a register 30 for the purpose of checking whether interruption is indicated by a central control device 1 or not. When the interruption indication flag is set, a status word is stored in an area 22 of a main storage part, and the interruption indication flag of the register 30 is reset to report interruption to the control part 1. This status word has an interruption report indication flag set and has the start address of the last command word which is completed at the interruption point. Thus, the control part 3 interrupts the transmission operation rapidly at the current command execution time in accordance with the interruption indication from the control part 1. Further, the interrupted operation is started very easily. |
