摘要 |
PURPOSE:To prevent the destruction of a shared memory due to erroneous access from a computer of another system, by splitting the shared memory into plural sets of computers, and displaying the operation transiting state of each computer to the part of a split shared memory area. CONSTITUTION:The shared memory 1 is split into three corresponding to computers 5, 6 and 7. The split areas are provided with areas A, B, C (transtion tables) representing the operation transit state. Shared memory controllers 2, 3 and 4 release the protection to its own area only and inhibits the write to the other systems. Every time the operating state of the computers 5, 6 and 7 is changed, the change is displayed on a corresponding transition table. Each computer discriminates the coupling state with the other systems depending on the transition table between its own system and the other systems. In case of dense coupling, the protection to the other system is released and the shared memory controllers 2, 3 and 4 are controlled so as to communicate information among the computers. |