| 摘要 |
PURPOSE:To prevent destruction of data in other shared memories by performing maintenance on condition that a shared memory is disconnected. CONSTITUTION:A means which indicates whether a shared member 1a is connected to a common bus 6 and can access the other systems or not and a means which reports contents of this indication to a CPU 5a are provided. The CPU 5a refers to these contents, and the CPU 5a executes a maintenance program when the shared memory 1a is not connected to the common bus 6. Consequently, though execution of the maintenance program is tried without disconnecting a cable because of mismaintenance, the maintenance program is not executed because the CPU 5a knows that the access of the other systems is possible. Thus, destruction of data in the other systems is prevented. |
