| 摘要 |
<p>PURPOSE:To reduce the possibility for a malfunction of a runaway, etc. by controlling a reset terminal of a microprocessor by a power-on signal, and a flip-flop for showing a fact that the microprocessor has been started and has entered into an operating state. CONSTITUTION:In case when an output signal 17 of a power-on switch output line 7 has become an L level for a short time of T1 by a noise signal, an output signal 18 of an FF 3 is an H level of a reset state, an output signal 19 of a gate circuit 4 becomes an H level about a T1 time, and a reset terminal R of a microprocessor 1 is released from a reset state about a T1 time and started. However, the microprocessor is programmed so that the FF3 is set after a T3 time, therefore, in case of T1<T3, an output signal 9 of the gate circuit becomes an L level before the FF 3 is set, and the microprocessor 1 is returned to the reset state. That is to say, even if a noise signal, etc. being shorter than T3 get on an output line of the power-on switch, the microprocessor 1 is returned to the reset state.</p> |
