人体红外传感器模块

#define PIR_PIN     4

void setup() 
{
  pinMode(PIR_PIN, INPUT);
  Serial.begin(115200);
}
void loop() 
{
  if(digitalRead(PIR_PIN) == HIGH)
  {
    Serial.println("There is someone here.");
  }else
  {
    Serial.println("There is no one here.");
  }
}