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code/HC-SR04/.pydio

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code/HC-SR04/HC-SR04.ino

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+// 定义引脚编号
+const int trigPin = 2;  //D4
+const int echoPin = 4;  //D2
+const int pinBuzzer = 5;  //D1
+
+// 定义变量
+long duration;
+int distance;
+
+void setup() {
+  pinMode(pinBuzzer, OUTPUT);
+  digitalWrite(pinBuzzer, LOW);
+  
+  pinMode(trigPin, OUTPUT); // 将trigPin设置为输出
+  pinMode(echoPin, INPUT); // 将echoPin设置为输入
+  Serial.begin(9600); // 启动串行通信
+}
+void loop() {
+  // Clears the trigPin
+  digitalWrite(trigPin, LOW);
+  delayMicroseconds(2);
+
+  //将trigPin设置为HIGH状态10微秒
+  digitalWrite(trigPin, HIGH);
+  delayMicroseconds(10);
+  digitalWrite(trigPin, LOW);
+
+  // 读取echoPin，以微秒为单位返回声波传播时间
+  duration = pulseIn(echoPin, HIGH);
+
+  // 计算距离
+  distance = duration * 0.034 / 2;
+  // 打印距离在串行监视器
+  Serial.print("Distance: ");
+  Serial.println(distance);
+  if (distance <= 20) { //如果距离小于10厘米小灯亮起
+    digitalWrite(LED_BUILTIN, LOW);
+    digitalWrite(pinBuzzer, HIGH);
+  } else {
+    digitalWrite(LED_BUILTIN, HIGH);
+    digitalWrite(pinBuzzer, LOW);
+  }
+
+  delay(1000);
+}