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    while (1)<br />        {<br />        <br />                 <br />                if(。。。)<br />                    {<br />                  IO0CLR = BEEP;   // 正确,蜂鸣一次                 <br />        DelayNS(50);<br />        IO0SET = BEEP;<br />        k++;<br />        if(k>10)<br />            {<br />            k*=2;<br />            }<br />                   }<br />             <br />            <br />         
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