| 摘要 |
<p>PURPOSE:To perform easily and quickly the AC (all clear) processing by outputting a clear signal of a one-shot pulse with a delay of a prescribed period of time from a time point when an AC switch is operated and clearing a read address, etc. of a program. CONSTITUTION:When an AC switch 15 is operated to start a normal action, an AC signal is applied to an AC circuit 16. Then an AC signal of a high level is fetched to the D input of a DFF16-1 with the rise timing of a clock signal phi. Thus the Q bar output of the DFF16-1 is set at a low level. As a result, a counter is started and the clear signal R delivered from an inverter 16-6 is set at a high level only when both Q outputs of the DFF16-2 and 16-3 are set at high levels. The signal R is set at a low level with the fall of the next clock phi. This action is repeated as long as the switch 15 is operated. Thus the one-shot pulses of the signal R are delivered every fixed cycle and applied to a ROM address control part 2. The contents of the part 2 are cleared every fixed cycle.</p> |
