| 摘要 |
PURPOSE:To attain automatic restoration if a selection control signal selects a faulty system by inhibiting a fault display when an external selection control signal is inputted to invert again the faulty system selected once into the normal system. CONSTITUTION:The case that a selected system is also faulty is explained. It is supposed that a signal source SC0 is selected, while signal source SC1 causes a fault and a signal fault suppervisory circuit AL1 outputs [1] as the initial state. The signal source is switched forcibly from the signal source SO0 to the signal source SC1 in this state, a positive pulse is given to a selection control signal input terminal CS and when the selection control signal CS goes to [1], [1] is inputted to a preset input Pr of a JK flip-flop circuit F1, the level of F1(Q) goes to [1], [1] is inputted to a selection signal input terminal SS and the source is switched to the signal source SC1. On the other hand, since a reset input R of an RS flip-flop circuit F2 goes to [1], the level of a terminal F2(Q') goes to [1]. |
