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与门：&
或门：|
非门：!

三门

各种运算

2.有人靠近

人体热释电传感器

• 单词
  .
  |word | meaning
  |--|--|
  |sensor|传感器
  |voltage|电压
  |current|电流

人体热释电传感器（HC-SR505）电路图

图中那个长得跟碟片一样的玩意就是人体热释电传感器。

代码：检测到人就报警

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(13,OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(13,LOW);
  while(!digitalRead(3));
  tone(12,233,10);
  digitalWrite(13,HIGH);
}

在上面代码基础上，增加一个听到声音就报警的功能：

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(13,OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(13,LOW);
  while(!digitalRead(3)&&!digitalRead(2));
  tone(12,233,5000);
  digitalWrite(13,HIGH);
  delay(5000);
  digitalWrite(13,LOW);
}

麦克风接线图

再将LED灯换成呼吸灯：

int red=10,green=9,blue=6;
void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(13,OUTPUT);
  pinMode(red,OUTPUT);
  pinMode(green,OUTPUT);
  pinMode(blue,OUTPUT);
  analogWrite(10,255);
  analogWrite(9,255);
  analogWrite(6,255);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(13,LOW);
  while(!digitalRead(3)&&!digitalRead(2));
  tone(12,233,1000);
  //digitalWrite(13,HIGH);
    for(int i=255;i>=0;i--) {analogWrite(red,i);delay(2);}
    analogWrite(red,255);
    for(int i=255;i>=0;i--) {analogWrite(green,i);delay(2);}
    analogWrite(green,255);
    for(int i=255;i>=0;i--) {analogWrite(blue,i);delay(2);}
    analogWrite(blue,255);
  //digitalWrite(13,LOW);
  
}

计算机能识别的颜色总数

向串口输入数据来设置颜色

作业

报警器代码：
把呼吸灯换回LED灯

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(13,OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(13,LOW);
  while(!digitalRead(3)&&!digitalRead(2));
  for(int i=100;i<=300;i++) tone(12,i,10);
  tone(12,300,2000);
  for(int i=0;i<20;i++)
  {
      digitalWrite(13,HIGH);
      delay(100);
      digitalWrite(13,LOW);
  }
  for(int i=300;i>=100;i++) tone(12,i,10);
  tone(12,100,2000);
  for(int i=0;i<20;i++)
  {
      digitalWrite(13,HIGH);
      delay(100);
      digitalWrite(13,LOW);
  }
}