Arduino 按键控制有源蜂鸣器

#define LED 13
#define KEY 2
#define Buzzer 3
int KEY_NUM = 0;	       //按键键值变量

void setup()
{
pinMode(LED,OUTPUT);		    //LED为IO输出
pinMode(KEY,INPUT_PULLUP);    //按键为IO带上拉输入
pinMode(Buzzer,OUTPUT);       //蜂鸣器为IO输出
digitalWrite(Buzzer,LOW);	    //蜂鸣器初始为不鸣叫
}

void loop()
{
ScanKey();			                 //按键扫描
if(KEY_NUM == 1)		                 //当有按键按下时
{
digitalWrite(LED,!digitalRead(LED)); //LED状态翻转
}
}

void ScanKey()
{
KEY_NUM = 0;
if(digitalRead(KEY) == LOW)
{
delay(20);				            //延时去抖动
if(digitalRead(KEY) == LOW)
{
BuzzerDi();			            //滴一声
KEY_NUM = 1;			            //设置键值
while(digitalRead(KEY) == LOW);	//松手检测
}
}
}

void BuzzerDi()
{
digitalWrite(Buzzer,HIGH);  //蜂鸣器响
delay(100);		          //延时20ms
digitalWrite(Buzzer,LOW);	  //蜂鸣器关闭
}