| 摘要 |
PURPOSE:To eliminate a control unit by allowing N-set of active units and a spare unit to supervise mutually a fault. CONSTITUTION:If a fault takes place in an active unit 101 in the active units 101, 102 fault information is given to an FF213 in the unit inside itself and a OR gate 219 of the spare unit 103 from a fault detection circuit 210. Thus, a trigger is given to a terminal C of an FF215 in the inside of the spare unit 103, a Q output of the FF215 is changed, switching information is fed to each terminal C of the FF213, 214 of the active units 101, 102 and to a changeover circuit 218 in the spare unit 103, the spare unit 103 is switched to the active unit and the active unit 101 is switched to the spare unit. After the active unit 101 is switched to the spare unit, when no fault takes place in the other active unit 102, no trigger is inputted to the FF214 of the active unit 102 and no changeover takes place. |
