| 摘要 |
<p>PURPOSE:To utilize internal constitution effectively and control the generation of an intermitent signal such as a buzzer sound generation drive signal by outputting a signal corresponding to the specific address counted value of a program counter as an intermittent oscillation signal. CONSTITUTION:When A is in the state of a high level 1 with an external output instruction, a signal is supplied to a latch circuit 21 to hold and set data contents transmitted to a data bus 11. When a signal B enters the state of the high level 1 with an external output instruction, a write command signal is supplied to and set in the 2nd latch circuit 22. When the data stored and held in the latch is ''1'', the contents of a program counter 18 are outputted from an AND circuit 25 and led out as an output signal through an OR circuit 26. The signal corresponding to the counted value Qn of a program counter 18 which is driven repeatedly and continuously to count is generated as the output signal of the OR circuit 26.</p> |
