采用msp430x16x单片机实现设计按钮电路控制蜂鸣器发出叫声，按一下，蜂鸣器响0.5S后停止，按第二下，蜂鸣 器响0.5S后停止0.5S，再响0.5S后停止，按第三下，蜂鸣器响1S后停止。循环操作。-Using msp430x16x MCU control circuit design buttons buzzer sounds, click the buzzer rang 0.5S after stopping, according to the second, the buzzer