| 摘要 |
<p>PURPOSE:To prevent the output of a wrong control signal to a controlled circuit by deciding the validity of the control signals outputted to a microprocessor and a peripheral circuit based on the input of an alarm signal. CONSTITUTION:A microprocessor/peripheral circuit 3 outputs a state signal 5 to an alarm detection circuit 2 to show the state of a microprocessor. The circuit 2 produces no alarm signal 7 as long as the signal 5 is normal, and a control signal deciding circuit 1 decides a valid control signal 6 outputted from the microprocessor and then outputs a control signal 8. When the microprocessor becomes abnormal, the circuit 2 produces the signal 7. Thus the circuit 1 decides a valid signal 6 sent from the microprocessor and then stops the output of the signal 8. As a result, the malfunction of a controlled circuit can be evaded.</p> |
