| 摘要 |
<p>PROBLEM TO BE SOLVED: To minimize the load that is applied on a control processor contained in a data communication controller when the control processor monitors periodically the state of every unit. SOLUTION: The state signals of the units 80-8K whose states are monitored are fetched into a control unit 5 after a control processor 6 contained in a data communication controller 170 starts a state monitoring operation. Thus, the change of the state signal of every unit is detected together with the inactive state of every unit. The change of the state signal of every unit fetched into the unit 5 is notified to the processor 6 by an interrupt. If a signal whose state change has not to be detected is included in the state signals of the units, the state change of the relevant signal is not detected and the occurrence of interrupts are evaded as much as possible when the state changes of signals are detected. Then the state monitoring operation is stopped according to the state (such as the occurrence of a fault) of the unit 5 where the processor 6 is mounted.</p> |
