| 摘要 |
PURPOSE:To improve the reliability of the title method by attaining a constitution where each computer owns its shared input/output device control part to perform the autonomous control of the device using right and secures the coincidence of the control parts in a multi- computer system with use of the broadcast communication containing a function code. CONSTITUTION:A master computer 1, the slave computers 2 and 3, and a shared input/output device 8 are connected to each other via a broadcast communication channel 7 and the device 8 is kept free. When a using right sequring request is produced from the computer 8 for the device 8, all computers 1, 2 and 3 receive the request respectively. This received request is valid only with the computer 1 and invalid with the computers 2 and 3 respectively. The computer 1 confirms the free state of the device 8 from the contents of an input/output device control part 4 and then updates the state of the device 8 to a state where the device 8 is used by the computer 3. Then the computer 1 gives the using right to the computer 3. Then a coincidence request of the part 4 is received by the computers 1-3 respectively from the computer 1, and this request is valid with the computers 2 and 3 only. Then both computers 2 and 3 update the received state of the part 4 of the computer 1 after copying it to their own control parts 5 and 6 respectively. Thus no shared memory is required end the reliability is improved in the control method of the device 8. |
