| 摘要 |
<p>PURPOSE:To increase both the assuredness and the reliability of the resetting circuit, by providing an OR circuit to the input side of the FF constituting the watch- dog timer (WDT) circuit in order to secure an application of the signals other than the power-on clear signal. CONSTITUTION:The OR circuit 40 is provided at the input side of the FF20 constituting the WDT circuit 20. Not only the power-on clear signal (c) but the clear signal (d) produced by the closed circuit of the switch 50 is supplied to the circuit 40. And one end of switch 50 is earthed. Thus the reset signal (r) is supplied directly to the microcomputer 10. In such way, the signal (c) or (d) is supplied to the input side of the circuit 40, and as a result the reset signal (e) can be supplied to the FF22 just by turning on the switch 50 and without turning on and off the power source. Thus the FF22 can be reset. Accordingly, no initialization is required for the peripheral units of the microcomputer 10.</p> |
